• Journal of Embryo Transfer
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• v.17 no.3
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• pp.239-249
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• 2002

Embryos derived from pig oocytes matured in mSOF are able to develop to blastocysts after IVF. Experiment 1 evaluated the effects of two maturation media (TCM-199 vs mSOF) on maturation rate, fertilization parameters, including penetration, polyspermy, male pronuclear formation, and the mean number of sperm penetrated per oocyte. Experiment 2 and Experiments 3 examined the effects of two maturation media on zona pellucida solubility and cortical granule distribution by transmissible electron microscopy, respectively. Experiment 4 assessed the effects of two maturation media on the in vitro embryo cleavage rate and development to blastocyst. Lastly, experiment 5 examined the cell number of blastocyst. An effect of media (P<0.05) was detected for mSOF on the mean number of sperm per oocyte. In TCM group, zona digestion time (196.5$\pm$15.5 vs 131.6$\pm$20.1 before IVF, 397.5$\pm$30.3s vs 185.3$\pm$16.4s after IVF, p<0.05) was higher in TCM-199 group. No significant effects of media was observed on cortical granule distribution between two groups by TEM. An effect (P<0.05) was observed on embryo development to blastocyst (16% vs 8%) but not on cleavage rates. No significant effects of media was observed on total cell number of blastocyst. We found that the high mean number of sperm penetrated per oocyte and the weaker zona pellucida on the basis of the digestion time was shown in pig oocytes matured in mSOF, however, porcine oocyte maturation with supplemented synthetic oviduct fluid medium (mSOF) resulted in blastocyst cell numbers comparable to those observed with Tissue Culture Medium 199.

• Reproductive and Developmental Biology
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• v.33 no.2
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• pp.93-98
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• 2009

In this study, bovine Dnmt1 cDNA was sequenced and detected Dnmt1 mRNA level in bovine tissues by northern blot, methylation pattern of genome by southern blot, specific localization of Dnmt1 in mouse and bovine preimplantation embryos by immunocytostaining and Dnmt1 protein level in ovary and testis by western blot. Bovine Dnmt1 cDNA sequence showed more homology with that of human than mouse and rat. The RNA level of Dnmt1 was 10 times higher expression in placenta than other tissues. This indicates that placenta was hypermethylated compared to others organs. The genomic DNA could not be cut by a specific restriction enzyme (HpaII) in placenta, lung and liver of bovine. It suggests that Dnmt1 in some somatic cells was already methylated. Dnmt1, which has the antibody epitope 1316~1616, was distributed in nucleus and cytoplasm including the stage of pronuclear stage and maturation of oocyte and gradually weaken to blastocyst stage compare to negative. In addition, Dnmt1 was strongly expressed in tetraploid embryo and cloned 8-cell than IVF 8-cell. An aberrant pattern of DNA methylation in cloned embryo may be abnormal development of fetus, embryonic lethality and placenta dysfunction. The somatic specific band (190kDa) was appeared in ovary and testis, but oocyte specific band (175kDa) was not. Further investigations are necessary to understand the complex links between the methyltransferases and the transcriptional activity of genes in the cloned bovine tissues.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.123-127
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• 1990

By nuclear transplantation technology twenty eight mice have been produced after transfer of heterozygous biparental eggs. Also heterozygous gynogenetic eggs with two female pronuclei and heterozygous androgenetic eggs with two male pronuclei have been obtained by injecting a male or female pronucleus with Sendai virus into the perivitelline space of enucleated haploid zygotes at pronuclear stage. The success rate of enucleation, karyoplast injection and fusion of both the pronuclei was 80.3, 83.4 and 81.8%, respectively. The overall pronuclei fusion rates by this technique were 56, 50 and 56% in biparental, gynogenetic and androgenetic eggs, respectively. The evidence was ascertained that the gynogenetic and androgenetic eggs were also able to develop in vitro up to blastocyst stage, even though their developmental potential was greatly diminished beyond 2-cell stage. The gynogenetic eggs were able to develop in vivo up to day 10 of pregnancy, while the androgenetic eggs failed to develop in vivo during the same period.

• Journal of Embryo Transfer
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• v.13 no.2
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• pp.89-96
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• 1998

Anti-phospholipid antihodies (aPL) have important roles in various pregnancy complications such as recurrent miscarrige, growth retardation, placental abruption and stillbirth. However, their biological actions on preimplantation development of oocytes are still unclear. In this study, we investigated whether either aPL containing sera or phospholipids could affect in vitro fertilization and development of mouse oocytes. Sera used in this study were collected from three patients and the presence of aPL in the sera was confirmed by enzymatic-linked immunosorbent assay. When mouse oocytes were cultured in a serum-free, Chatot, Ziomek and Bavister (CZB) medium (Experiment 1), addition of aPL-containing sera (10%) to CZB medium did not. significantly (P>0.05) influence sperm penetration of oocytes. However, development to the blastocyst stage was significantly (P<0.05) inhibited by serum addition, and formation of morulae (16-23% vs. 58%) and blastocysts (0-4% vs. 21%) was markedly reduced compared with no addition (Experiment 2). In Experiment 3, pronuclear stage embryos were cultured for 96 h in GZB medium supplemented with 1 $\mu$g /ml phosphatidyl ethanolamine, 1 $\mu$g/ml phosphatidyl inositol or 1 $\mu$g /ml phosphatidyl choline. No increase in embryo development was found after addition of the phospholipids to CZB medium. These results suggest that 1) aPL have an inhibitory role in preimplantation development of mouse embryos, and that 2) the action of aPL may be related to a specific phospholid (s) rather than the tested phospholipids in the present study.

• Korean Journal of Animal Reproduction
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• v.26 no.1
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• pp.41-51
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• 2002

The present study was carried out to examine the effect of cysteamine in vitro maturation (IVM) of porcine oocytes and development of porcine IVM/IVF Embryos. The results were summarized as follows : 1. The rates of nuclear maturation, penetrated oocytes, pronuclear formation, polyspermic oocytes and mean numbers of the penetrated sperm were not different in NCSU23 maturation medium with 0, 25, 50 and 100 $\mu$M cysteamine (P〉0.05). 2. The rates of blastocyst formation at day 7 after in vitro fertilization in 0, 25, 50 and 100 $\mu$M cysteamine were 17.9$\pm$6.1, 17.4$\pm$6.3, 24.2$\pm$1.9 and 16.9$\pm$2.0%, respectively. And the total cells were 30.7$\pm$2.4, 34.9$\pm$2.8, 39.6$\pm$2.3 and 36.8$\pm$3.6, respectively. Fifty $\mu$M cystealnine group was significantly higher than those of any other treatment groups (P＜0.05). 3. The ratios of ICM/total cells in 20~40% category were 20.5, 41.6, 19.5 and 31.5%, respectively. Twenty five $\mu$M cysteamine group was higher than those of other groups. 4. The rates of blastocyst formation at day 7 in the NCSU-23 culture medium of porcine IVF-produced embryos with 0, 25, 50, and 100 $\mu$M cysteamine were 16.0$\pm$0.2, 13.6$\pm$1.7, 25.0$\pm$0.8 and 15.7$\pm$4.5%, respectively. And the total cells were 27.0$\pm$3.7, 36.1$\pm$4.8, 34.0$\pm$3.8 and 25.2$\pm$4.4, respectively. Fifty $\mu$M cysteamine group was significantly higher than those of any other treatment groups (P＜0.05). 5. The ratios of ICM/total cells in 20~40% category were 53.8, 30.0, 16.6 and 11.1%, respectively. The addition groups of cysteamine were lower than those of control group. In conclusion, these results suggested that the addition of 50 $\mu$M cysteamine in the IVM medium and 25~50 $\mu$M cysteamine in IVC medium were effective on the blastocyst formation and total cells of blastocysts.

• Journal of Embryo Transfer
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• v.31 no.2
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• pp.117-121
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• 2016

Although piglets have been delivered by embryo transfer (ET) with in vitro produced (IVP) embryos and blastocysts, a success rate has still remained lower level. Unlike mouse, human, and bovine, it is difficult to a production of piglets by in vitro fertilization (IVF) because of an inappropriate in vitro culture (IVC) system in pig. Therefore, the present study was conducted to investigate whether minimized exposure time in IVC can improve the pregnancy and delivery rates of piglets. Immediately after IVM, the oocytes were denuded and co-incubated with freshly ejaculated boar semen for 3.5 to 4 hours at $38.5^{\circ}C$ under 5% $CO_2$ in air. To avoid long-term exposure to in vitro state, we emitted IVC step after IVF. After that the presumptive zygotes were transferred into both oviducts of the surrogate on the same day or 1 day after the onset of estrus. Pregnancy was diagnosed on day 28 after ET and then was checked regularly every month by ultrasound examination. The 3 out of 4 surrogates were determined as pregnant (75%) and a total of 5 piglets (2 females and 3 males) were delivered at $118.3{\pm}2.5$ days of pregnancy period. In conclusion, a short-term exposure time may be an important factor in the production of IVP-derived piglets. It can be apply to the in vitro production system of transgenic pig by IVF, cloning, and pronuclear microinjection methods.

• Korean Journal of Animal Reproduction
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• v.22 no.4
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• pp.395-403
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• 1998

In this study we determined fertilization processes and developmental ability of porcine oocytes following injection of round spermatid in the presence and absence of artificial activation. Electrical stimulation at 2 h before spermatid injection significantly increased the incidence of normal fertilization as compared to those following injection without stimulation or with stimulation immediately after injection. The incidences of two pronuclear formation and apposition were not different in oocytes between following intracytoplasmic spermatid and spermatid nucleus injection. Indirect immunocyto chemistry and laser scanning confocal microscopy study revealed that microtubuels were organized from the oocyte cortex following round spermatid injection, and this seemed to move both male and female pronuclei into the oocyte center. At 6 days following injection blastocoele formation was seen in the eggs following round spermatid (25%) and round spermatid nucleus injection (27%). However, none of oocytes developed to the blastocyst stage at 6 days following sham injection. The average cell numbers of blastocysts at 8 days following injection of spermatid and spermatid nucleus were 87 to 99. These results suggested that either round spermatid or it's nudeus can be used to produce viable embryos by injection into unfertilized oocytes in the pig.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.2
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• pp.193-201
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• 1999

In this study we determined fertilization processes and developmental ability of porcine oocytes following injection of round spermatid in the presence of artificial activation. Electrical stimulation at 3 h before spermatid injection significantly increased the incidence of normal fertilization as compared to those following injection without stimulation or with stimulation immediately after injection. The incidences of two pronuclear formation and apposition were not different in oocytes between following intracytoplasmic spermatid and spermatid nucleus injection. Indirect immunocytochemistry and laser scanning confocal microscopy study revealed that micro tubules were organized from the oocyte cortex following round spermatid injection, and this seemed to move both male and female pronuclei into the oocyte center. Paternal mitochondria which are introduced with spermatid have been observed up to 4-cell. Our study indicated that either round spermatid or it's nucleus can be used to produce viable bovine embryos by injection into unfertilized oocytes.

• Clinical and Experimental Reproductive Medicine
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• v.32 no.3
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• pp.243-251
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• 2005

Objective: Low-dose aspirin have been proposed to improving endometrial receptivity and pregnancy rate in COH-IVF by increasing endometrial perfusion. However, the effect of low-dose aspirin in COH-IVF could be negligible because there have been large quantity of other important factors responsible for changing endometrial perfusion accompanied by COH procedure. In contrast, in frozen-thawed embryo transfer cycles which were not accompanied by COH procedure, the effects of low-dose aspirin in endometrial blood flow seems to be more certain than in COH-IVF cycles. In this study, we analyzed the effect of low-dose aspirin treatment on implantation and pregnancy rates in patients undergoing frozen-thawed embryo transfer Methods: From January 2003 to December 2003, total 264 cycles from 264 patients who attended infertility clinic at Samsung Cheil Hospital were enrolled in this study. All cases included in this study, embryos were frozen and thawed at the pronuclear stage and three days after incubation, at least 2 or more good quality embryos were transferred into uterus. In study group, low dose aspirin (100 mg/day) was administrated from the first or second date of menstrual day to 9 days after embryo transfer. On the other hand, control group did not take any medicine except estradiol valerate for endometrial priming. Several variables including implantation and pregnancy rates were compared in both groups. After then, each groups were stratified by endometrial thickness checked at embryo transfer (ET) day such as (28 mm versus <8 mm) and same variables above described were compared between study and control groups. Results: The mean age, infertility duration, endometrial thickness at embryo transfer day and mean number of transferred embryo were not significantly different in both groups. Also, implantation rates (study group: 15.8%, control group: 20.5%) and pregnancy rate (study group: 45.1%, control group: 43.5%) were not significantly different between two groups. (p>0.05) After we analyzed same variables stratified by endometrial thickness checked at embryo transfer day, we could not found any significant difference between study and control groups. Conclusions: Low-dose aspirin treatment seems to have no advantage of improving implantation and pregnancy rates in patients undergoing frozen-thawed embryo transfer.

• Korean Journal of Agricultural Science
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• v.34 no.1
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• pp.19-35
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• 2007

The present study was carried out to examine the effect of EGF and IGF-I in vitro maturation (IVM) of porcine oocytes and development of porcine IVM/IVF embryos. The results were summarized as follows : 1. The rates of nuclear maturation, penetrated oocytes, pronuclear formation, polyspermic oocytes and mean numbers of the penetrated sperm were not different in NCSU-23 maturation medium with 0, 1, 5 and 10 ng/ml EGF and IGF-I (P>0.05). 2. The rates of blastocyst formation at day 7 after in vitro fertilization in 0, 1, 5 and 10 ng/ml EGF groups were $11.2{\pm}1.5%$, $15.0{\pm}8.3%$, $16.8{\pm}2.8%$ and $21.4{\pm}2.0%$, also 0, 1, 5 and 10 ng/ml IGF-I groups were $11.2{\pm}1.5%$, $15.0{\pm}8.3%$, $16.8{\pm}2.8%$ and $21.4{\pm}2.0%$, respectively. In the total cells case, EGF groups were $22.8{\pm}3.7$, $25.7{\pm}5.5$, $26.0{\pm}4.2$ and $35.1{\pm}4.7$, also IGF-I groups were $21.5{\pm}3.7$, $25.2{\pm}2.8$, $26.2{\pm}2.9$ and $33.2{\pm}3.6$, respectively. Both 10 ng/ml EGF group and 10 ng/ml IGF-I group were significantly higher than those of other treatment groups (P<0.05). 3. The rates of blastocyst formation at day 7 in the NCSU23 culture medium of porcine IVF-produced embryos with 0, 1, 5, and 10 ng/ml EGF groups were $14.0{\pm}1.7%$, $16.2{\pm}1.4%$, $16.9{\pm}1.2%$ and $23.1{\pm}1.6%$, also 0, 1, 5, 10 ng/ml IGF-I groups were $13.6{\pm}1.7$, $15.7{\pm}4.5$, $16.0{\pm}0.2$ and $25.0{\pm}0.8$, respectively. And in the total cells case, EGF grups were $21.8{\pm}2.9$, $25.2{\pm}2.8$, $39.7{\pm}2.7$ and $46.2{\pm}3.6$, also IGF-I groups were $20.7{\pm}2.9$, $26.2{\pm}2.9$, $24.6{\pm}2.4$ and $46.1{\pm}3.5$, respectively. Both 10 ng/ml EGF group and 10 ng/ml IGF-I group were significantly higher than those of any other treatment groups (P<0.05). In conclusion, these results suggested that the addition of 10 ng/ml EGF and IGF-I were effective on the blastocyst formation and total cells of blastocysts.