• Journal of Embryo Transfer
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• v.31 no.3
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• pp.221-226
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• 2016

The aim of the present study was to assess the embryo development and survivability of post-thawed bovine embryos produced in vitro by addition of cysteine. The rates of metaphase II formation were not differed significantly among three groups(TCM199 73.8%, TCM199 with 0.3% cysteine 76.9%, TCM199 with 0.5% cysteine 83.8%, respectively). No difference of cleavage rate(70.6~74.6%) was seen among three culture medium(TCM199 70.6%, CR1aa 71.3%, SOF 74.6%) with 0.5M cysteine. however, Significantly(P<0.05) higher development rate into blastocyst stage by 0.5M cysteine addition was obtained in SOF medium(35.6%) than in TCM199(27.6%) or CR1aa(26.6%), however no significant differences in the cleavage rates were among three culture medium. After frozen the blastocysts cultured with 0.5M cysteine, The re-expansion rates were 61.3%~86.4% among groups, and hatching rates were 26.3%~46.9% among groups, the rates of re-expansion and hatching were significantly(P<0.05) higher in SOF medium(86.4% and 46.9%) than those in TCM199(61.3% and 26.3%) and CR1aa medium(87.1 and 44.4%). After thawing, the blastocyst re-expansion rate was significantly(P<0.05) higher in in vivo (87.1%) and in vitro (70.3%) embryos. In conclusion, our results demonstrate that supplementation of IVM and IVC medium with 0.5M cysteine improved the quality of in vitro production embryo and post- thawed embryo. Future studies comparing these media systems in well-designed trials should be performed.

• Journal of Embryo Transfer
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• v.23 no.1
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• pp.37-42
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• 2008

This study was performed to improve the pregnancy rates of recipients following transfer of bovine embryos produced in vivo. Superovulation response didn't showe significant differences between each season (4.18 in spring; 4.36 in summer; 5.50 in fall; 4.38 in winter). Pregnancy rate was significantly different (p<0.05) between fresh (43.4%) and frozen embryos (17.2%). In administration of hCG to recipients, the pregnancy rate of fresh embryos (45.7%) was slightly higher than that of control (35.3%), but the pregnancy rates of frozen embryos in control group (25.0%) was higher than that of hCG group (16.0%). When synchrony of recipient and embryo was -2, -1, 0 and 1, the pregnancy rates were 20.0, 45.0, 30.3 and 26.3%, respectively. The pregnancy rates of recipients synchronized by naturally or $PGF_{2{\alpha}}$, CIDR/$PGF_{2{\alpha}}$ and E/P/CIDR/$PGF_{2{\alpha}}$/E treatments were 35.3, 48.0, 29.0 and 40.0%, respectively. Gestation lengths and birth weights of female and male calf were 288 and 290.5 days, 28.3 and 30.0 kg, respectively. The results were showed that the superovulation response was not affected by seasons, and also pregnancy rate didn't increase by administration of hCG, synchrony of embryo and recipients, synchrony methods. Further study and concern should be focused on improving the embryo freezing and pregnancy rate for commercial embryo transfer.

• Journal of Embryo Transfer
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• v.25 no.4
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• pp.221-227
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• 2010

Early cleavage is a reliable prognostic tool for successful embryo transfer in assisted reproduction because early cleaved embryo show better pregnancy rate after transfer. There for, preparation of good embryo recipient is important factor to optimize efficiency of pig cloning. The present study was performed to evaluate the effect of early cleavage on the in vivo development of cloned embryos and to analyze breed, parity and estrous synchrony to optimize recipient for pig cloning. In vitro matured porcine oocytes derived from local slaughterhouse and fibroblasts derived from miniature pig fetuses were used for somatic cell nuclear transfer (SCNT). Reconstructed embryos were transferred to recipient pigs on the same day of SCNT or after 1~2 days of in vitro culture for selecting early cleaved embryos. Breed, parity and date of standing estrous of recipients were recorded for analysis. After 25~35 days after embryo transfer pregnancy was diagnosed using ultrasonography, and pregnant recipients were monitored till delivery. Between purebred and crossbred, no significant difference was founded in both pregnancy and delivery rates. However, early cleaved embryos showed significantly higher pregnancy (46.2%) and delivery (12.8%) rates compared to non-selectively transferred group (24.8% and 4.5%, respectively). The results also showed that the recipients showing standing estrous on the same day of SCNT and less than 4 parities were most suitable for pig cloning.

• Journal of Veterinary Clinics
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• v.27 no.2
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• pp.154-158
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• 2010

Embryo Transfer (ET) is one of the assisted reproductive technologies and a useful tool for improving herds. The purpose of this study is to produce the calves using frozen embryos which were produced in the top one percent Holstein in Canada by ET. One hundred seventeen recipients were used for surrogate mothers and seventy cows were diagnosed to be pregnant. Fifty seven calves were born successfully and thirteen out of them failed to produce viable calves (abortion: 4, stillbirth: 9). Their gestational length, birth body weight and sex ratio for all the viable calves(n = 57) were $278.1{\pm}3.6$ days (range: from 271 to 286 days), $44.0{\pm}3.0\;kg$ (range: from 37 to 49 kg) and 57.9 vs. 42.1 % (male 33 and female 24), respectively. Microsatellite analysis confirmed that they were derived from frozen embryos. In conclusion, this study demonstrated that viable calves derived from frozen-thawed embryos from Canada were born by ET.

• Journal of Embryo Transfer
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• v.11 no.2
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• pp.95-101
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• 1996

The present study investigated the effect of treatment with nocodazole on the efficiency of cell cycle synchronization and development of mouse 4-cefl embryos. In addition, developmental ability of reconstituted embryos that received nuclei from 4-cell embryos synchronized with nocodazole at M phase was examined in vitro and in vivo. (1) When 4-cell blastorneres exposed to culture medium containing l$\mu$g /ml nocodazole for 2, 4, 6 and 8 hrs, 40% (40/10l), 75% (l19/159), 85% (87/102) and 97% (155/160) of nuclei were synchronized at M phase, respectively. (2) Treated with nocodazole for 4 hrs, the proportion of 4-cell embryos developed to blastocysts (98%, 60/61) was not significanUy different from that of the control embryos (98%, 196/201). However, the developmental ability of 4-cell embryos treated for 8 (87%, P<0.05)and 12 hrs (76%, P

• Plant Biotechnology Reports
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• v.3 no.4
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• pp.333-340
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• 2009

Developmental anomalies in the plumule meristem of peanut (Arachis hypogaea L.) somatic embryos resulted in poor shoot differentiation and reduced plant recovery. Existing meristems with caulogenic potential have never been tested for embryogenesis in peanut. The present experiment was designed to test the mature zygotic embryo axis derived plumule with three meristems for somatic embryogenesis. Embryogenic masses and embryos developed from the caulogenic meristems in the axils. Exposure of 2 weeks in primary medium with $90.5{\mu}M$ 2,4-D suppressed the shoot tip differentiation temporarily which then regained the ability to form the shoot on withdrawal of 2,4-D. Exposure of 4 weeks in primary medium with $90.5{\mu}M$ 2,4-D suppressed the shoot tip differentiation irreversibly. No shoot formation was noted from the tips in any of the cultures which were in secondary medium with $13.6{\mu}M$ 2,4-D. Development of somatic embryos directly from axillary meristems was confirmed histologically. Conversion frequency of these embryos was 11%. Thus, in this report, we describe a method to obtain somatic embryos from the determined organogenic buds of the axillary meristem, by culturing the nodal explant vertically on embryo induction medium. It also displays the possibility of obtaining both embryogenic and organogenic potential in two parts of the same explant simultaneously. The possibility of extending this approach for genetic transformation in in vivo system through direct DNA delivery or Agrobacterium injection in meristems can also be explored. Using Agrobacterium rhizogenes, we have demonstrated the possibility of gene transfer in the axillary meristems of seed-derived plumule explant.

• Journal of Embryo Transfer
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• v.26 no.3
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• pp.171-180
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• 2011

In this study I report that in vitro development rates of bovine nuclear transfer embryos activated either with boar sperm cytosolic factor (SCF) or with ionomycin followed by cycloheximide (CHX) and subsequent in vivo developmental rates after embryo transfer are related to blastocyst quality as evaluated by apoptosis analysis. SCF was extracted from porcine semen then purified for post-activation injection after nuclear transfer. The optimal timing for SCF injection was determined to be at least 22 h post-IVM for parthenogenetic activation of bovine oocyies. A total of 364 oocytes were successfully enucleated and 268 (73.6%) fused and were injected with SCF. The survival rate of fused and injected embryos was 109/113 (96.5%) after 2 h. The cleavage rates of nuclear transfer embryos after 3 d of culture in the ionomycin/CHX treated group were significantly higher than those of the SCF-activated group (93.3% vs 81.7%, p<0.01, respectively). However, at 7 d and 9 d there was no significant difference between the total developmental rates to blastocyst for either treatment group. Total blastocyst cell numbers were also not significantly different between the two activation treatments (ionomycin/CHX: 149.5${\pm}$7.7 vs. SCF: 139.3${\pm}$4.4 cells). In contrast, the apoptotic levels in the SCF blastocysts were higher than those produced after the chemical treatment (28.2${\pm}$5.1% vs. 8.8${\pm}$0.6%, respectively). A total of 18 expanded or hatching blastocysts was transferred to nine synchronized recipients in each activation group; 5/9 (55.5%) and 2/9 (22.2%) were pregnant at 40 d in the ionomycin/CHX treatment and SCF activated group, respectively. However, only one went to term in the ionomycin/CHX treatment while none of the pregnancies from the SCF group were maintained by 90 d. In conclusion, these results suggest that SCF derived from different species is a limited activator to be used for activation after bovine nuclear transfer in lieu of a chemical activation protocol.

• Journal of Embryo Transfer
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• v.12 no.2
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• pp.141-149
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• 1997

This study was carried out to investigate the effect of vitrification and slow freezing methods on the post-thaw developmental rate of rabbit zygotes. After exposing rabbit zygotes in EFS solution for 0.5, 1, 2, 3 and S min at room temperature, they were washed with 0.5 M sucrose solution, D-PBS and TCM-199 and then cultured in TCM-199 plus 10% FBS with bovine oviduct epithelial cells(BOEC) to examine whether the cryoprotectant induced injury during the various exposure periods. The embryo development rates to hatched blastocyst after exposing in EFS solution for 3 and 5 min(40.0 and 16.7%) were significantly lower than in 0.5, 1 and 2 min(63.0, 72.0 and 54.5%), respectively. The post-thaw development rates to hatched blastocyst were significantly(P<0.05) higher in in vivo morula with intact mucin coat(85.2%) and mucin seperated morula(77.8%) than those of in vitro morula(58.5%) and zygote(5.9%), hut no difference was shown between in vitro morulae and mucin separated morula. The cryoprotectant dilution procedures showed no effects on the post-thaw development rates to hatched blastocyst under the present culture conditions. The post-thaw development to hatched blastocyst in the rabbit zygotes was not significantly different between the slow freezing(12.8%) and vitrification(5.9%). These results indicated that the rabbit frozen zygotes could he successfully developed in vitro to hatched blastocysts, though their developmental rate was very low, compared with morula stage embryos, in either vitrification or slow freezing procedure under the present conditions.

• Journal of Life Science
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• v.16 no.4
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• pp.566-570
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• 2006

Pronuclear microinjection (PMI) is a primary method for producing transgenic mice and offers a powerful tool for investigating gene function in vivo. The method has several reported advantages and disadvantages. Here, we report another potential shortcoming. The survival rate of fertilized one cell-stage embryos was significantly reduced after PMI procedure (65.4% (1202/1838)). In addition, the proportion of embryos developing to full-term was also significantly lower than that of embryos not undergoing PMI (26.5% (319/1202) vs 41.9% (57/136)). Moreover, 3 out of 21 (14.3%) founder control mice which were non-transgene-carrying littermates of transgenic founders showed histopathological changes in their liver, which was comparable to that in of transgenic lineages (4 out of 27 (14.8%)). In conclusion, the mechanical damages in chromosomes occurring during PMI procedure may be a potential factor influencing phenotypes of transgenic mice.

• Molecules and Cells
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• v.41 no.2
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• pp.134-139
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• 2018

Here, we report isolation of multiple long non-coding RNAs (lncRNAs) expressed tissue-specifically during murine embryogenesis. One of these, subsequently came to be known as Redrum, is expressed in erythropoietic cells in fetal liver and adult bone marrow. Redrum transcription is also detected during pregnancy in the spleen where extramedullary hematopoiesis takes place. In order to examine the function of Redrum in vivo, we generated a gene-targeted murine model and analyzed its embryonic and adult erythropoiesis. The homozygous mutant embryo showed no apparent deficiency or defect in erythropoiesis. Adult erythropoiesis in bone marrow and in the spleen during pregnancy likewise showed no detectable phenotype as red blood cells matured in normal fashion. The phenotype is in contrast to the reported function of Redrum in vitro, and our observation implies that Redrum plays in vivo an accessory or supplementary role whose loss is compatible with normal erythropoiesis.