• Clinical and Experimental Reproductive Medicine
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• 제27권1호
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• pp.39-46
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• 2000

Objective: A number of studies to improve in vitro culture conditions have been tried over past ten years by using co-culture system with helper somatic cells. However, the mechanism of coculture is poorly understood. This study was designed to understand the mechanism for the mode of actual action of co-culture using co-culture system of ICR strain's 1-cell embryos with human oviduct epithelial cells by examining the effect of conditioned medium and contactless coculture using a cell culture insert on the embryo development and by measuring the level of superoxide anion from conditioned medium after co-culture. Methods: ICR strain's zygote embryos were cultured in medium alone (control), coculture, conditioned medium, or contactless coculture system for 6 days. Conditioned media (CM) were prepared as following 5 groups. All CM were collected after culturing oviduct cells for 2 days. CM-1 was stored at $-20^{\circ}C$ until use, and CM-2 was prepared just before use as a culture medium. CM-3 was cocultured with embryos and retrieved just before use. CM-4 and CM-5 were derives from the microfilteration of CM-2 and CM-3, respectively, using Microcon-10 (10 kDa molecular weight cut-off). The percentage of the embryos developed to hatched blastocyst stage and the level of superoxide anion in supernatant from medium alone culture (control), coculture, and contactless coculture were measured. Results: The rates of embryo development to the hatched blastocyst stage were significantly higher in coculture (43%) than in control (0%) (p<0.05). The CM-1 group had no embryo development since 2-cell embryonic stage, whereas the CM-2, CM-3, CM-4 and CM-5 groups had the improved development to 4 or 8 cell embryo stage, but the similar rate of development to hatched blastocyst compared to control. The effect of coculture on embryo development was disappeared in the contactless coculture group. The level of superoxide anion was significantly reduced in coculture group compared to control. Conclusion: It is concluded that the present coculture system overcomes the 2-cell block in vitro and improves the embryo development. This beneficial effect may be due to the direct cell-cell contact between embryo and helper cells or the removal of deleterious components from medium rather than the embryotrophic factors.

• 한국수정란이식학회지
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• 제14권2호
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• pp.89-92
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• 1999

효율적인 homozygous 동물을 생산하기 위한 실험의 단계로 염색체가 4배체인 수정란의 이용성을 타진하기 위해 생쥐 수정란과 cytochalasin B를 사용하여 4배체 유도에 관한실험을 수행하였다. 생쥐 2-세포기 수정란을 10$\mu\textrm{g}$/ml 농도의 cytochasin B로 약 20시간 배양하였을 때 모든 수정란은 발육을 거의 멈추었으나, 이 수정란을 cytochalasin B-free medium에 체외배양하였을 때 발육이 재개되어 48시간 후 상실기나 배반포기까지 약 74%의 발육율을 나타내었다. 그러나 발육된 수정란의 세포수는 대조구에 비해 휠신 적은 것으로 나타났다. 염색체 분석결과 cytochalasin B로 처리한 대부분의 수정란은 4배체인 것으로 나타났고 약간의 수정란은 mosaicism과 다배체를 나타내기도 하였다. 그러므로 cytochalasin B를 이용하여 효과적으로 4배체의 수정란을 유도할 수 있는 것으로 나타났다.

• 한국동물생명공학회지
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• 제38권2호
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• pp.47-53
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• 2023

Despite numerous advances in in-vitro embryo production (IVP), many documented factors have been shown to influence the development of mammalian preimplantation embryos and the success of IVP. In this sense, elevated levels of reactive oxygen species (ROS) correlate with poor outcomes in assisted reproductive technologies (ART) due to oxidative stress (OS), which results from an imbalance between ROS production and neutralization. Indeed, excessive production of ROS compromises the structural and functional integrity of gametes and embryos both in vivo and in vitro. In particular, OS damages proteins, lipids, and DNA and accelerates cell apoptosis. Several in-vivo and in-vitro studies report an improvement in qualityrelevant parameters after the use of various antioxidants. In this review, we focus on OS and the source of free radicals and their effects on oocytes, sperm, and the embryo during IVP. In addition, antioxidants and their important role in IVP, supplementation during oocyte in vitro maturation (IVM), in vitro culture (IVC), and semen extenders were discussed. Nevertheless, various methods for determining the level of ROS in germ cells have been briefly described. Still, it is crucial to develop standardized antioxidant supplement systems to improve overall IVP success. Further studies should explore the safety, efficacy, mechanism of action, and combination of different antioxidants to improve IVP outcomes.

• Reproductive and Developmental Biology
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• 제39권2호
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• pp.29-36
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• 2015

Pigs are considered an ideal source of human disease model due to their physiological similarities to humans. However, the low efficiency of in vitro embryo production (IVP) is still a major barrier in the production of pig offspring with gene manipulation. Despite ongoing advances in the associated technologies, the developmental capacity of IVP pig embryos is still lower than that of their in vivo counterparts, as well as IVP embryos of other species (e.g., cattle and mice). The efficiency of IVP can be influenced by many factors that affect various critical steps in the process. The previous relevant reviews have focused on the in vitro maturation system, in vitro culture conditions, in vitro fertilization medium, issues with polyspermy, the utilized technologies, etc. In this review, we concentrate on factors that have not been fully detailed in prior reviews, such as the oocyte morphology, oocyte recovery methods, denuding procedures, first polar body morphology and embryo quality.

• 한국수정란이식학회지
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• 제4권1호
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• pp.28-34
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• 1989

These experiments were carried out to determine the effect of cell stage in embryo bisection on the sub-Sequent in vitro and in vivo development in mouse. The embryos of ICR mouse were microsurgicaily bisected at 2-cell, 4-cell, 8-cell, morula and blastocyst stage using a microsurgical blade attached a micromanipulator. These demi-embryos without zona pellucida were cultured up to blastocyst stage and transferred to pseudopregnant mice, and the development of these demi-embryos was compared with the results of intact embryos of the corresponding cell stage. The successful rate of mouse embryo bisection at 4-cell stage (59.0%) was significantly (p <0.05) lower than those at 8-cell (75.6%), 2ce11 (80.7%) or morula stage (84.8%), and highest at blastocyst stage (95.7%). When the bisected embryos without any damage from microsurgery were cultured in vitro up to blastocyst,the in vitro de'velopment of demi-embroys bisected at morula to blastocyst was 91.6 to 95.3%, which was similar to the culture result of intact embryos of corresponding stage. However, the in vitro development of demi-em-bryos bisected at 2- to 8-cell stage was signiflcantiy (p <0.05) lower.The post-transfer implantation rate of demi-embryos developed in vitro to eu-blastocyst were 19.6 and 25.4% in demi-embryos bisected at morula and blastocyst stage,respectively and not significantly (P <0.05)different from the result of intact embryos of the same stage. However, the implantation rates of demi-embryos bisected at 2- or 8-cell stage were significantly (P <0.05) lower than the result from the intact embryos of the corresponding stage.

• 한국수정란이식학회지
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• 제5권2호
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• pp.11-22
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• 1990

Remarkable progress has recently been made in embryo transfer technology, resulting in the birth of IVF and nuclear transfer offsprings in swine. However, further progress of the technology to (I) make a safe, effective and economic estrual-cycle synchronization compound, (2) regulate each step of sperm capacitation (3) induce monospermic fertilization, (4) in vitro grow and mature oocytes, (5) fertilize the oocytes efficently, (6) culture the oocytes to the blastocyst stage in defined media, (7) produce multiply copies of embryos with superior genetic merit, (8) preselect the sex of these superior offsprings, and (9) preserve embryos by freezing and storage in liquid nitrogen is required before this promising technology is applied routinely to swine for practical use.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.47-47
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• 2003

The present study was conducted to determine the expression of the antioxidant enzyme(CuZn-SOD, Mn-SOD and GPX and apoptosis gene(caspase-3) for in vitro culture in in vitro maturation and in vitro fertilization(IVM/IVF) embryos in porcine. Porcine embryos derived from IVM/IVF were cultured in NCSU23 medium under 5% $CO_2$ in air at 38.5$^{\circ}C$. The patterns of gene expression for several antioxidant enzyme and apoptosis genes during preimplantion porcine embryo development were examined by the modified semi-quantitative single cell reverse transcriptase- polymerase chain reaction (RT-PCR). Preimplantation porcine embryos produced by IVM/IVF have expressed mRNAs for CuZn-SOD and GPX, whereas transcripts for Mn-SOD have not detected at any developmental stages. Expression of caspase-3 mRNA was detected at 2 cell, 8 cell, 16 cell and morula stages. The fas ligand transcripts were detected in porcine blastocyst. These results suggest that various antioxidant enzymes and apoptosis genes play crucial roles in in vitro culture of porcine IVM/IVF embryos.

• 한국수정란이식학회지
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• 제11권3호
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• pp.241-248
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• 1996

This study was conducted to improve the production efficiency of in vitro produced (IVP) embryos in Korean Native cows. The optimal conditions and procedures for in vitro maturation(IVM), in vitro fertilization(IVF) and in vitro culture(IVC) of bovine follicular oocytes and IVP embryos were evaluated. Immature follicular oocytes were collected fiom the follicles of bovine ovaries obtained from abattoirs. The oocytes of Grade I and II for IVM were cocultured with monolayered bovine oviductal epithelial cells(BOEG) or granulosa cells in TCM-199 solution supplemented with follicle stimulating hormone, lutenizing hormone, estradiol-17$\beta$ and heat inactivated fetal calf serum at 39$^{\circ}C$ under 5% $CO_2$ in air for 14 to 24 hours. Most of the oocytes(93%) matured to metaphase II in 24 hours. The cocultured IVM oocytes were fertilized in vitro at significantly(P<0.05) higher rate with BOEC(83.8%) and with granulosa cells(84.6%) than the non-cocultured IVM oocytes(73.6%). The IVM-IVF embryos developed to morula and blastocyst at significantly(P<0.05) higher rate in coculture with BOEC(41.2%) than with granulosa cells(23.1%) or conditioned medium(23.4%).

• Clinical and Experimental Reproductive Medicine
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• 제18권1호
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• pp.49-53
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• 1991

The development of 2-cell mouse embryos to the blastocyst stage in vitro has been used as a quality control for the media empolyed for human in vitro fertilization. There was a comparison between the quality control data of the culture medium as ascertained by 2-cell mouse embryos development and sperm motility and the data from fertilization and cleavage of human oocytes. However, there was no obvious association between fertilization and cleavage of human oocytes and the quality of the medium ascertained by mouse embryo development and sperm motility.

• 한국가금학회지
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• 제28권2호
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• pp.125-133
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• 2001

The goal of this paper was to examine the qualify zygote-acquiring method for in-vitro culture and the in-vitro culture method of the acquired zygote from a technological perspective. We have reported the results on the introduction of foreign DNAs using the described culturing method. After performing in-vitro and surrogate eggshell culture on a zygote acquired from the abdomen of a hen, 25.8% hatchability was acquired. After microinjecting foreign DNAs into the acquired zygote and performing in-vitro and surrogate eggshell culture using the same method, 13.1∼11.7% hatchability was acquired. Having compared the developments of the control subjects and the experimental subjects, the viability of the experimental subjects on the 4∼5th day of culturing was much lower compared to that of the control subjects. This is a result that shows that the microinjection process of foreign DNAs might have a negative effect on the existence of the embryo; therefore, various technical attempts should be made to minimize such negative effects. Having microinjected foreign DNAs into the zygote of a hen to produce transgenic chickens, 3 transgenic founders were Produced and 70 G1 progeny were produced as a result of the progeny test that had been performed to the present.