• Journal of Embryo Transfer
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• v.23 no.4
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• pp.291-298
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• 2008

We separately cultured follicular oocytes collected from individual ovaries of slaughtered Korean native cows and examined both the embryonic development rate and pregnancy rate after embryo transplantation according to the meat yield and quality grades of the source beef carcass. Oocytes from meat yield grade B cows exhibited a higher fertilization rate and embryonic developmental rate to the eight-cell stage than oocytes from grade A or C animals (p<0.05), but there was no significant difference in rate of development to the blastocyst stage among meat yield grades A, Band C. The oocyte cleavage rate and development rate to the eight-cell stage from meat quality grade 3 cattle was higher than grades 1++, 1+, 1 and 2 (p<0.05). Embryos derived from grade animals displayed a development rate to the blastocyst stage of 19.4%, which was also higher than all other meat quality grades (p<0.05). Transplantation of in vitro-cultured oocytes from meat yield grade A ovaries led to a higher pregnancy rate (64.2%) than in vitro-cultured oocytes from meat yield grade B ovaries (56.5%), but there was no significant difference between the two groups in pregnancy or abortion rates. In conclusion, embryonic development rate and pregnancy rate has a close relation to meat quality grades of the source beef carcass, this results is to give information for the Korean native cows improvement of breed.

• Clinical and Experimental Reproductive Medicine
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• v.39 no.3
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• pp.114-117
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• 2012

Objective: It is well known that fresh blastocyst transfer results in better pregnancy outcomes with a smaller number of transferred embryos compared with cleavage stage embryo transfer. However, in terms of frozen-thawed blastocyst transfer, only a few studies are available. We aimed to evaluate clinical outcomes of frozen-thawed embryo transfer (FET) with blastocysts. Methods: Retrospective analysis of FET cycles with blastocysts (B-FET) between Jan 2007 and June 2009 was performed. Age-matched FET cycles with cleavage stage embryos (C-FET) during the same period were collected as controls. A total of 58 B-FET cycles were compared with 172 C-FET cycles and also compared with those of post-thaw extended culture blastocysts from frozen pronuclear stage embryos (22 cycles). Results: There was no difference in the patient characteristics of each group. The embryos' survival rates after thawing were comparable (>90%) and there was no difference in the implantation rate or clinical and ongoing pregnancy rate among the three groups. Conclusion: In FET, blastocyst transfers may not present better pregnancy outcomes than cleavage stage embryo transfers. A further large-scale prospective study is needed.

• Journal of Ginseng Research
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• v.21 no.1
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• pp.43-48
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• 1997

Dynamic parameters of biochemistry including the POD (peroxidase) activity, contents of DNA and RNA, isozymes of POD and ES (esterase) in American send (Panax quinquefolium L.) seed are reported in the present paper. The dynamic changes of POD activity proved that the PAS (physiological afterripening stage) is a stage in which some substances are prepared for seed germination. The POD activity correlated with ER (embryo ratio) significantly DNA content changed little only within 0.0036∼0.013 mg/ml, which did not correlate with ER. RNA content changed from 0.1539 to 1.0313 mg/ml and correlated significantly with RE during all of the embryo afterripening. None of the POD isozyme band was obtained in ESGS (embryo slowly growth stage), but five bands in ERGS (embryo rapidly growth stage) and six bands in PAS. Four bands of ES isozymes were obtained in ESGS, but six bands in ERGS, particularly, the content of ES isozymes increased in PAS. All of these may provide some information for understanding the dormancy mechanisms of American song seed.

• Journal of Life Science
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• v.11 no.4
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• pp.311-315
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• 2001

To identify the effects embryo developmental stage and gelrite concentration on plant regeneration in seed culture of rice, mature and immature seeds of rice were cultured on the $N_{6}$ medium supplemented with2 mg/$\ell$ 2.4-D and different levels of gelrite(0.2~1.0%). The calli formed immature embryos were produced more plants than those from mature embryos. The maximum frequency of plant regeneration was achieved in the culture of the calli of immature embryos which was harvested at the 21$^{th}$ day after pollination. The plant regeneration on the medium with gelrite was more accelerate than that on the medium with agar. The highest frequency(55%) of plant regeneration was obtained from the calli transferred to the medium with 6g/$\ell$ gelrite.

• Korean Journal of Animal Reproduction
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• v.12 no.2
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• pp.77-83
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• 1988

This study was done with mouse embryo to assess effects of freezing media containing sucrose, freezing metods(1-F, 0.3$^{\circ}C$/min;2-F, 3-5$^{\circ}C$/min;3-F, 15$^{\circ}C$min;4-F, LN2 vapour) and cell freezers on the embryo survival determined using the FDA test. The results are summarized as follows. 1. The FDA score obtained with 1, 2, 3 and 4-F was 3.8, 3.6, 3.2 and 3.2, respectively. There was a significant difference(P<0.05) between 1-F, 3-F and 2-F, 4-F. 2. The score at the morular stage(3.8) higher(P<0.005) than the blastocyst stage of embryos(3.2). 3. No difference (P>0.05) was found between the score obtained with a automatic embryo freezer(4.0) and a liquid nitrogen container(3.7).

• Journal of Embryo Transfer
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• v.7 no.2
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• pp.81-88
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• 1992

Cryopreservation of mouse embryos biopsied at 4-cell stage was investigated by ultrarapid freezing. Four-cell embryos were obtained from ICR mice on 55h after hCG injection. Zona pellucida of the embryos were partially dissected with a cutting pipet, and then single blastomeres were biopsied from the embryos followed by incubation in $Ca^2$+ and $Mg^2$+-free M16 medium for 30min. Biopsied embryos cultured for lh or 15h were frozen by ultrarapid freezing method using 3M DMSO or 5M glycerol as a cryoprotectant, respectively. The developmental rate of biopsied embryos after ultrarapid freezing and thawing to blastocysts was 81 % in the group of biopsied embryos cultured for lb and 98% in the group of biopsied embryos cultured for 15h, respectively. When biopsied embryos after ultrarapid freezing and thawing were transferred to the uteri of pseudopregnant recipients, normal live young were born. These results suggest that this freezing method can efficiently cryopreserve biopsied mouse embryos.

• Journal of Embryo Transfer
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• v.8 no.1
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• pp.31-36
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• 1993

The post-thaw survival of mouse embryos of the various developmental stages was determined after cryopreservation by vitrification in a solution containing ethylene glycol, Ficoll and sucrose (EFS). All the embryos were equilibrated for 2 minutes just prior to freezing. The number of blastomeres during in vitro development was counted by nuclei higher rates of post-thaw survival were obtained from the embryos of 2-cell(92.2%), 8-cell(77.2%) or morula stage(90.0%) than those of blastocyst stage(62.7%). The number of blastomeres per embryo following in vitro culture for 24 hours was significantly(P<0.05) smaller as 66.0f22.3 in vitrified and thawed morulae than fresh morulae(91.7$\pm$12.2).

• Korean Journal of Animal Reproduction
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• v.7 no.1
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• pp.24-29
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• 1983

These experiments were carried out to obtain basic information necessary of the success of in vitro culture of blastomeres separated from mouse embryo. Total 446 single blastomeres separated from 2-, 4- and 8-cell mouse embryos by protease treatment (0.5% in Whittingham's medium), were cultured under the gas phase of 5% CO2 in air at 37$^{\circ}C$. whittingham's medium was used for culture of blastomeres. The results obtained in these experiments were summerized as follows: 1. Of total 446 blastomeres cultured, 127(87.0%), 134(73.2%) and 77(65.8%) blastomeres separated repectively from 2-, 4- and 8-cell embryos were developed to morula or blastular stages. 2. The numbers of blastomeres, being separated from 2-. 4- and 8-cell embryos and developing to blastocysts containing inner cell mass, were 97(76.4%), 86(64.2%) and 33(42.9%) respectively. 3. After in vitro culture of the blastomeres, the incidence of trophoblastic vesicles increased with the development of the cell stage of embryo. In case of blastomeres separated from 8-cell embryos, 50.6% of blastomeres that developed to blastular stage was trophoblastic vesicles.

• Journal of Plant Biology
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• v.6 no.2
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• pp.3-6
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• 1963

As a part of embryological studies of Panax ginseng, megasporangium and megagametophyte formations were investigated. Ovule is found to be auatropous. Small-sized nucellus is surrounded by thick layered single integument. As the embryo sac develops, the nucellus along with some parts of the inner epidermis of integument disintegrates and completely disappers at flowering stage. Embryo sac takes the type of typical Polygonum although antipodal cells disappear and polar nuclei fuse to form secondary nucleus before fertilization. Mature embryo sac consists of egg apparatus and large secondary nucleus lying adjacent to the egg. Besides the normal ovule, tiny incomplete ovule develops near the base of style. Frequently two normal ovules are formed in a single locule. Chromosome number counted is PMC is n=24.

• Korean Journal of Plant Resources
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• v.16 no.2
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• pp.160-167
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• 2003

In order to investigate the effects of developmental stage of embryos and plant growth regulators on mass production of Zantedeschia spp. Southern Light, immature zygotic embryos of Zantedeschia spp. Southern Light were cultured on Murashige and Skoog(1962) basal media or containing 2,4-D, NAA and BA. Globular embryos did not grow on any of the 2,4-D, NAA and BA combinations. The most suitable stage of immature zygotic embryo culture on the induction callus and multiple shoot was at early cotyledonary embryo stage, and at this stage of embryos were germinated up to 87.5%. The whitish watery callus and yellowish compact nodular callus produced on all 2,4-D, NAA and BA media. The best combination for inducing embryogenic callus was 0.5 mgL NAA and 1.0 mg/L BA. Whitish watery calli have been subcultured for more than 8 months and have retained their producing ability, Plant regeneration was only obtained by direct shoot development and yellowish compact nodular calli. Abundant plantlets were regenerated from cotyledonary stage of embryo culture on MS medium supplemented with 0.5 mg/L NAA and 1.0 mg/L BA. Supplementation of the media with 10％ coconut water showed as the best concentration for plant differentiation from direct developed of shoots. The number of regenerated plants from one embryo could be seperated 25-35s plantlets. All yellowish compact callus-derived plantlets were transferred to pots containing a mixture of vermiculite, perlite and sand(1:1;1 v/v) and 100% of divided plantlets were phenotypically normal.