• Clinical and Experimental Reproductive Medicine
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• v.22 no.3
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• pp.279-285
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• 1995

Despite the frequent incidence of embryo fragmentation in early human embryos, the reason of the embryo fragmentation has not been known yet. This study was conducted to investigate the histological difference(s) between fragmented (FR) and non-fragmented (NFR) human embryos focusing on comparison of mitochondrial distribution and protein synthesis. Multi-pronuclei zygotes (MPZ) such as three or more pronuclei containing in human in vitro fertilization and embryo transfer (IVF-ET) program were used for this study. MPZ were cultured in TCM-199 supplemented with 10% of human fetal cord serum (hFCS) in 5% $CO_2$ incubator at $37^{\circ}C$ for 24 hours. The cleaved embryos to 2-4 cells after 24 hours were grouped by their grade of fragmentation. Embryos were stained with Rhodamine123 (Rh123) and fluorescence was evaluated under the fluorescence microscope through PB 450-490 filter (Leitz). Regarding to protein synthesis during early human embryogenesis, there is no significant difference in the amount of synthetic proteins between FR and NFR embryos. Distribution of cytoplasmic organelles in embryos was evaluated by transmission electron microscope (TEM). The cytoplasmic distribution of mitochondria was different between FR and NFR embryos. The mitochondrial distribution was even in NFR, whereas severely aggregated in FR. It is not able to clarify in the present study whether this uneven mitochondrial distribution in FR embryo is the reason for embryo fragmentation or is the result from fragmentation. Physiological disparity related to the mitochondrial distribution may be one of the reasons for embryo fragmentation. Further studies should be addressed to investigate the physiological differences between FR and NFR embryos.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.54-54
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• 2005

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.136-136
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• 2003

Mainly due to deficiencies in nuclear reprogramming, gene expression and DNA fragmentation, which result in early and late embryonic losses, the overall success rate achieved by cloning techniques to date is low. This present study compared the incidences of DNA fragmentation during development of IVF, parthenotes (PT), nuclear transfer (NT) and transgenic (TG) embryos. Terminal deoxynucleotidyl transferase (TdT) nick-end labelling (TUNEL) with propidium iodide counter staining was used for determination of DNA fragmentation and total number, respectively. TG and NT donor cells were fetal fibroblasts with or without transfection with EGFP, and cultured in DMEM+15% FCS until confluent, for 5 days. At 19 h post-maturation (hpm), enucleated oocytes were reconstructed with donor cells and activated at 24 hpm with the combinations of ionomycin (5 M, 5 min) and cyclo-heximide (10 g/ml, 5 h) after electric fusion by a single DC pulse (1.6 KV/cm, 60 sec). Parthenotes were produced by the same activation protocol at 24 hpm. (중략)

• Korean Journal of Animal Reproduction
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• v.26 no.4
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• pp.385-394
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• 2002

This study was constructed the correlations of the embryonic developmental rates and the frequency of chromosome aberration using ear-skin-fibroblast cell in nuclear transfer (NT) derived embryos. Karyoplast-oocyte complexes were fused and activated simultaneously, then cultured for seven days to assess development. The developmental rates of NT and in vitro fertilization (IVF) embryos were 55.4% vs 63.5%, 31.7% vs 33% and 13.4% vs 16.8% in 2 cell, 8 cell and blastocyst, respectively. Firstly, the frequency of chromosome aberrations were evaluated using fluorescent in situ hybridization (FISH) technique with porcine chromosome 1 submetacentric specific probe. Chromosome aberration was detected at day 3 on the embryo culture, the percentages of chromosomal aneuploidy in NT and IVF embryos at 4-cell stage were 40%, 31.3%, respectively. Secondly, embryonic fragmentation was evaluated at 4-cell stage embryo. Frequency of embryonic fragmentations was in 51.3% of NT, 61.3% of IVF, 28.9% of parthenogenetic activation at 4-cell stage. The proportion of fragmentation in NT embryos was higher than activation embryos. This result indicates that chromosomal abnormalities and embryonic fragments are associated with low developmental rate in porcine NT embryo. It is also suggest that abnormal porcine embryos produced by NT related with lower implantation rate, increased abortion rate and production of abnormal fetuses.

• Journal of Embryo Transfer
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• v.24 no.1
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• pp.65-69
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• 2009

The aim of the present study was to investigate the cleavage pattern, its developmental ability and apoptosis of porcine embryo in vitro. Morphology data on a total of 919 embryos were analyzed retrospectively. Forty-eight hours after insemination, embryos were classified into five groups based on the cleavage state as follows; 1 cell, 2 cell, 4 cell, 5 to 8 cell and fragmentation. These groups were cultured another 120 hours and then evaluated for blastocyst formation. Blastocyst formation rates were significantly higher in 4 cell (42.5%) and 5 to 8 cell (48.6%) cleaving groups than in other groups (p<0.05). On the other hand, 2 cell and fragmentation groups produced 4.9% and 3,9% blastocysts, respectively. And we could verify that in the event of 2 cell block and fragmentation of embryo. To analyze the apoptotic frequency in preimplantation development of porcine IVF embryos, all cells of each blastocyst were performed by TUNEL assay. There were no significantly differences in the total cell numbers of embryos and apoptotic cell rate in blastocysts among the each classified groups. Data suggest that 4 cell and 5 to 8 cell cleaving embryos at 48 hour after insemination have high developmental competence, and may be an useful parameter to predict the development of preimplantation embryos and to study using preimplanation embryonic research.

• Clinical and Experimental Reproductive Medicine
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• v.49 no.3
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• pp.185-195
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• 2022

Objective: This study aimed to determine the effect of sperm DNA fragmentation (SDF) on the cumulative live birth rate (CLBR) in intracytoplasmic sperm injection (ICSI) cycles in couples with unexplained infertility. Methods: We conducted a prospective study of 145 couples who underwent ICSI cycles for unexplained infertility. Based on the SDF rate, patients were categorized into a low SDF group (SDF ≤30%, n=97) and a high SDF group (SDF >30%, n=48). SDF was assessed using the acridine orange test on density gradient centrifugation prepared samples. The CLBR was calculated as the first live birth event per woman per egg collection over 2 years. Results: The high SDF group (SDF >30%) showed a significantly lower CLBR (p<0.05) and a significantly higher miscarriage rate (p<0.05) than the low SDF group (SDF ≤30%). No significant difference was observed in the implantation and cumulative pregnancy rates between the two SDF groups. The total number of embryo transfers was stratified further into fresh and frozen embryo transfers. In the fresh embryo transfers, there were significant differences in the implantation rates, clinical pregnancy rates, and live birth rates (p<0.05) between the low SDF and high SDF groups. However, in the frozen embryo transfers, there were no significant differences in clinical outcomes between the two groups. In the multivariable logistic regression analysis, SDF was a predictor of CLBR (p<0.05) when adjusted for possible confounding factors. Conclusion: High SDF was associated with a lower CLBR and a higher miscarriage rate in the ICSI cycles of couples with unexplained infertility.

• Journal of Embryo Transfer
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• v.25 no.2
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• pp.111-116
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• 2010

Sperm chromatin integrity is essential for successful fertilization and development of an embryo. Reported here is a quantification of DNA fragments which is intimately associated with reproductive potential to provide one of criteria for sperm chromatin integrity. Three sperm populations were considered: CONTROL (no treatment), UV irradiation (48mW/$cm^2$, 1h) and $H_2O_2$ (oxidative stress induced by hydrogen peroxide, 10 mM, 50 mM and 100 mM). DNA fragments in boar sperm were evaluated by using ligation-mediated quantitative real-time polymerase chain reaction (LM-qPCR) assay, which relies on real-time qPCR to provide a measure of blunt 5' phosphorylated double strand breaks in genomic DNA. The results in agarose gel electrophoresis showed no significant DNA fragmentation and no dose-dependent response to $H_2O_2$. However, the remarkable difference in shape and position was observed in melting curve of LM-qPCR. This result supported that the melting curve analysis of LM-qPCR presented here, could be more sensitive and accurate than previous DNA fragmentation assay method.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.72-73
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• 2005

• Journal of Embryo Transfer
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• v.27 no.1
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• pp.45-50
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• 2012

The objective of this study is to estimate the effect of adding TES to LEY and FGE freezing extender for the sperm viability, acrosomal morphology and DNA fragmentation from miniature pig sperm, we evaluated sperm characteristics in TFGE, TLE and LEY with various thawing condition ($37^{\circ}C$ for 20 sec, 45 sec and $75^{\circ}C$ for 5 sec, respectively), and in different concentration of glycerol at 1%, 1.5%, 3%. The sperm viability and normal acrosome intact(NAI) in TFGE (Viability : $60.3{\pm}2.4$, NAI : $58.6{\pm}2.2%$), TLE ($61.3{\pm}2.4$, $62.2{\pm}2.2%$) extender significantly(p<0.05) increased than that in LEY ($50.2{\pm}2.4$, $54.5{\pm}2.2%$) extender thawed at $75^{\circ}C$ for 5 sec. According to the results from glycerol concentration, the viability and NAI of miniature pig sperm in 1.5% glycerol TLE ($66.1{\pm}3.2$, $66.2{\pm}1.0%$) was highest among the experimental groups. In accordance with this, DNA fragmentation rates was the lowest in TLE ($43.3{\pm}0.5%$) while that in LEY ($63.5{\pm}2.3%$) is the highest. Therefore, these results suggest that TLE extender method for freezing- thawing of miniature pig sperm increased the viability after thawing.

• Biomedical Science Letters
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• v.23 no.4
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• pp.372-379
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• 2017

This study was investigated to test whether paternal DNA that was destined for degradation was properly licensed by testing for the presence of mini-chromosome maintenance protein (MCM) 7 and origin recognition complex (ORC) 2 in the paternal pronuclei. ORC2 is one of the first licensing protein to come on and MCM7 is one of the last licensing protein to come on. Zygotes were prepared by injection of control and treated sperm injection (ICSI). To control for DNA breakage, epididymal spermatozoa were treated with DNase I to fragment the DNA, then injected into oocytes. The presence of MCM7 and ORC2 in the pronuclei of mouse zygotes was tested by immunohistochemistry, just before the onset of DNA synthesis, at 5 h after fertilization, and after DNA synthesis began, at 9 h post fertilization. We found that in all cases, both MCM7 and ORC2 were present in both pronuclei at 5 h after sperm injection, just before DNA synthesis began. This indicates that no matter how extensive the DNA damage, recruitment of licensing proteins to the origins of replication was not inhibited. Sperm DNA fragmentation does not prevent licensing of DNA replication origins. Furthermore, the embryo recognizes DNA that is damaged by nucleases. Our data indicate that the one-cell embryo does harbor a mechanism to prevent the replication of severely damaged DNA from spermatozoa, even though the embryos do not undergo classical apoptosis.