• Reproductive and Developmental Biology
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• 제31권2호
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• pp.127-131
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• 2007

Embryonic germ (EG) cells are undifferentiated stern cells isolated from cultured primordial germ cells (PGC). These cells share many characteristics with embryonic stem cells including morphology and pluripotency. Undifferentiated porcine EG cell lines demonstrating capacities of differentiation both in vitro and in vivo have been established. Since EG cells can be cultured indefinitely in an undifferentiated state, whereas somatic cells in primary culture are often unstable and have limited lifespan, EG cells may provide inexhaustible source of karyoplasts in nuclear transfer (NT). In this study the efficiencies of NT using porcine EG and fetal fibroblast cells were compared. Two different techniques were used to perform NT. With conventional NT procedure (Roslin method) involving fusion of donor cells with enucleated oocytes, the rates of development to the blastocyst stage in EG and somatic cell NT were 16.8% (59/351) and 14.5% (98/677), respectively. In piezo-driven microinjection (Honolulu method) of donor nuclei into enucleated oocytes, the rates of blastocyst formation in EG and somatic cell NT were 11.9% (15/126) and 9.4% (9/96), respectively. Regardless of NT methods used in this study, EG cell NT gave rise to comparable rate of blastocyst development to somatic cell NT. Overall, EG cells can be used as karyoplast donor in NT procedure, and embryos can be produced by EG cell NT that may be used as an alternative to conventional somatic cell NT.

• Asian-Australasian Journal of Animal Sciences
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• 제20권9호
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• pp.1354-1360
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• 2007

The aim of this study was to evaluate if oocytes, aspirated from postovulatory ovarian follicles of superovulated rabbits 14 h post-hCG administration, could be efficiently used as ooplasm recipients for somatic cell nuclear transfer (SCNT). Within a common SCNT protocol, a comparison between oocytes recovered by direct aspiration (aspirated) from available ovarian follicles and oocytes flushed out from oviducts (flushed) was carried out. The results showed that maturation and enucleation rates of aspirated oocytes were 70.7% and 69.2%, significantly lower than 95.3% (p<0.01) and 83.6% (p<0.05), respectively, from flushed oocytes. However, following enucleation of matured oocytes as ooplasm recipients for SCNT, no difference was recorded in fusion and cleavage rates, as well as blastocyst development from cleaved embryos or hatching of blastocysts between aspirated and flushed groups. Additionally, some matured aspirated and flushed oocytes were also used for immediate parthenogenetic activation and the resulting embryo development was not significantly different. Results from this study show the following: i) the majority of oocytes aspirated from postovulatory ovarian follicles of superovulated rabbits 14 h post-hCG administration are matured and can be used directly as ooplasm recipients for SCNT; ii) the reconstructed embryos derived from these oocytes have similar in vitro developmental ability to those flushed from the oviducts.

• 한국수정란이식학회지
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• 제17권2호
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• pp.109-115
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• 2002

The present study was conducted for the production of transgenic cloned cows those secrete human lactoferricin into milk by somatic cell nuclear transfer (NT). To estimate detrimental effects of gene transfection on transgenic cloned embryo production, development rates of NT embryos were compared between transfected and non-transfected cumulus and ear fibroblast cells. An expression plasmid for human lactofericin (pbeta-LFC) was constructed by inserting a bovine beta-casein promoter, a green fluorescent protein (GFP) marker gene, and human lactoferricin target gene into a pcDNA3 plasmid. Two bovine somatic cell lines (cumulus cell and ear fibroblast) were established and transfected with the expression plasmid using a liposomal transfection reagent, Fugene6 as a carrier. Cumulus cell and ear fibroblast were transfected at the passage of 2 to 4, trypsinized and GFP-expressing cells were randomly selected and used for somatic cell NT. Developmental competences (rates of fusion, cleavage, and blastocyst formation) in bovine transgenic somatic cell NT embryos reconstructed with non-transfectecd cells were significantly higher than those from transfected cells in cumulus cell and ear fibroblast (P＜0.05). This study indicated that transfection of done. cell has detrimental effect on embryo development in bovine transgenic NT.

• 한국발생생물학회지:발생과생식
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• 제1권1호
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• pp.67-77
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• 1997

Mammalian ovary consists of various growing stages of follicles. Ovarian follicular growth and differentiation, however, can be distinguished into recruitment, growth, selectiona nd ovulation. while only minute of the selected follicles ovulate their oocytes, all the rest follicles disappear by atresia. this atresia is an important event of which physiological mechanism must be resolved. The present study was carried out to investigate the effects of various doses of pregnant mare's serum gonadotropin (PMSG) on the oocyte quality, ovulation rate, and the early embryonic development in immature mice. Immature mice were administrated with 5, 20, or 40 IU PMSG. At every 12 hour up to 72 hour after treatment, body and ovary weights were measured. Oocytes were flushed from the oviducts under the dissecting microscope and observed under the inverted microscope. Late 2-cell embryos were collected from the mice which were superovulated by the same dosage of PMSG followed by 5 IU hCG 47 hours after PMSG-treatment. The percentage of abnormal oocytes was higher in 20 or 40 IU PMSG-treated animals than 5 IU PMSG-treated ones. Ovulation occured at 12 hours afger PMSG injection in all experimental groups. The percentage of retrieved abnormal oocytes increased in the 20 or 40 IU PMSG-treated goups but not in 5 IU PMSG-treated group. There was no significant difference in the mating rate among the groups [52.6% (10/19), 66.7% (10/15), 44.0% (11/25) : 5, 20, 40 IU group respectively] ; however, ther was a significant (p<0.01) increase of embryo retrieval rates in 5 and 20 IU-treated groups compared with that in 40 IU-treated group [89.2% (239-268), 85.5% (224/262), 40.0% (18/45)]. There was significant (p<0.01) increase of embryo development rates in 5 IU-treated group compared with that in 20 and 40 IU-treated group [231/239(96.7), 179/224(79.9), 77.8(14/18)]. In conclusion, higher doses of PMSG injection increased the occurrence of abnormal oocytes ovulation in immature mice. The most of oocytes collected from 5 or 20 IU-PMSG-treated group has fertilizabioity. But in mice injected iwth higher doses of PMSG, their oocytes exhibit less fertilizability and, even fertilized, all oocytes are not fully capable of development.

• Reproductive and Developmental Biology
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• 제29권3호
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• pp.193-199
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• 2005

인간의 불임을 극복하기 위한 번식공학 기술의 효율성을 증가시키기 위해 성세포의 동결이 널리 수행되고 있으나 동결 기술의 효율성에 있어서 논란의 여지가 있다. 본 연구에서는 체외수정란을 생산하기 위한 난자세포질내 정자미세주입(ICSI) 시술에 사용되는 정자와 이들 기술을 이용 생산한 체외수정란의 동결이 배 발생 및 임신에 미치는 효과를 조사하였다. ICSI방법으로 체외수정란을 생산하는 경우 정자의 동결이 체외수정, 발생 및 임신에 영향을 미치지 않았으며, 특히 동결융해한 사출 및 정소정자에 의한 체외수정율과 발생율 및 임신율도 차이가 없었다. 한편 체외수정란을 동결하는 경우 완만동결과 초자화동결에 의한 체외수정란의 생존율과 임신율은 차이가 없었으나, 동결수정란은 신선수정란에 비하여 임신율이 유의하게 낮았다(p<0.05). 결론적으로 ICSI에 사용되는 정자와 달리 ICSI에 의해 생산된 수정란을 동결하는 경우 임신율을 저하시킬 수 있다.

• Reproductive and Developmental Biology
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• 제29권3호
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• pp.141-144
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• 2005

This experiment was to investigate whether the mitochondria function assessment can be used for the prediction of sperm fertility through examining the correlation between mitochondria fluoromicroscopic frequency of frozen-thawed eight Hanwoo bull semen using rhodamine123 (R123) and in vitro embryo development following fertilization. Individual sperm were stained in 5 ${\mu}g/mL$ R123-added calcium-free Sp-TALP for 30 min at 0 h, 6 h, 12 h and 24 h after thawing and examined their mid-piece under an epifluorescence microscope using 495 nm excitation filter (x1,000). Three replications were taken, and at least 300 sperm per individual were examined. When semen samples were separated into two groups (good and poor) by sperm motility and fluorescent frequencies at just after thawing, average fluorescent frequencies were remarkably reduced as time going (0 h; $53.29{\~}72.94\%$, 6 h; $21.40{\~}58.90\%$, 12 h; $8.26{\~}25.93\%$, 24 h; $1.00{\~}13.78\%$, irrespective of selected group, and there were no differences at 6 h or 12 h after thawing between selected groups but indicated significant difference at 24 h after thawing (p<0.05). In vitro fertilization rates in good and poor groups ranging $70.8{\~}77.8\%$ and $52.1{\~}84.5\%$, respectively, were not significantly different. However, in vitro development rates of the same groups ranging $25.7{\~}40.0\%$ and $12.9{\~}1.8\%$, respectively, were significant different (p<0.05). These results demonstrate that mitochondria fluoromicroscopic assessment of frozen-thawed bovine sperm may be used as a criterion to select more fertile sperm.

• 한국가축번식학회지
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• 제27권4호
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• pp.339-347
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• 2003

The purpose of this study was to investigate the development of bovine nuclear transfer (NT) embryos cultured in serum-free conditions. Bovine NT embryos cultured in various culture conditions were compared blastocyst development, total cell number and apoptosis using TUNEL assay. In experiment 1, blastocyst rates of NT embryos were significantly higher (P<0.01) in FBS (22.0％) and BSA (26.6％) groups than in PVA (6.3％) group. Total cell number was significantly higher in FBS (78.4$\pm$19.4) and BSA (90.9$\pm$29.1) groups than in PVA group (46.0$\pm$0.0). Apoptotic cell number was significantly fewer in FBS (3.1$\pm$1.4) and BSA (1.7$\pm$1.4) groups than in PVA group (7.0$\pm$20.0) However, all of results were not different between the FBS and BSA group. In experiment 2, blastocyst rates of NT embryos were significantly higher (P<0.05) in fatty acid free-BSA (FAF-BSA) group (26.8％) than in fraction V-BSA group (11.2％). Total cell number were somewhat higher in FAF-BSA group (89.8$\pm$30.7) than in fraction V-BSA group (88.1$\pm$19.3). Apoptotic cell number were somewhat fewer in FAF-BSA (1.7$\pm$1.5) group than in fraction V-BSA group (4.2$\pm$2.9). These findings suggest that serum free condition were effective for the in vitro development of bovine NT embryos. Therefore, we concluded that fatty acid free-BSA has beneficial effect in development bovine NT embryos and can be use as a serum substitute.

• Reproductive and Developmental Biology
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• 제35권3호
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• pp.295-300
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• 2011

The objective of this study was to evaluate efficiency of methyl-beta-cyclodextrin (MBCD) in the sperm preservation of bull. For this study, the freezing of diluted semen were added with Triladyl containing 20% egg-yolk and/or 0, 1, 5, 10 and 20 mM MBCD before freezing process. Analysis of viability in frozen-thawed sperm was estimated by SYBR14/PI double stain, hypoosmotic swelling test(HOST) and acrosome damage with FITC-PNA, and mitochondria activation with Rhodamin123 by flow-cytometry. The sperm viability was significantly in 0 mM and 5 mM concentrations of MBCD than other groups (p<0.05). However, the HOST was significantly lower at 20 mM concentration of MBCD than other concentrations (p<0.05). In addition, acrosome damage and mitochondria activation rates were significantly lower at 20 mM concentration of MBCD than other groups (p<0.05). In conclusion, the viability of sperm was not significantly different among concentrations of MBCD 0, 5 and 10 mM, but MBCD 20 mM was significantly lower than other groups. In addition, as concentrations of MBCD was high, HOST, acrosome damage and mitochondria activation rates had a negative effect in bull sperm.

• Asian-Australasian Journal of Animal Sciences
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• 제20권5호
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• pp.718-724
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• 2007

Considerable attention has been focused on the cloning of mammalian embryos, as a consequence of poor development, in order to enhance the application of genetic engineering. Experiments were conducted to compare the developmental competence of parthenotes and reconstructed (NT) rabbit eggs with fetal fibroblasts (FFs) following various activation regimens. Oocytes and NT eggs were exposed to: electric stimulation (EST, Group 1) and EST followed by 6-dimethylaminopurine (DMAP, Group 2), cycloheximide (CHX, Group 3) or DMAP/CHX (Group 4). Pronuclear (PN) status, cleavage, blastocyst development and the ploidy were assessed. In parthenote groups 1, 2, 3 and 4, the PN formation differed significantly. And, the cleavage and blastocyst rates were 41.7 and 5%, 75.6 and 53.7%, 68 and 36%, 82.1 and 52.6%, respectively, among treatments. Polyploidy was observed in 17.2% of EST plus DMAP and 44.9% of EST plus DMAP/CHX groups. In SCNT groups (Group 1, 2, 3 and 4), the cleavage and blastocyst rates were 28.6 and 7.1%, 58.3 and 29.2%, 56.8 and 24.1%, 64.5 and 27.8%, respectively. The chromosomal composition differed significantly (p<0.05) among treatments. In Group 2 and 3, 53.8% and 81.8% of embryos revealed diploid chromosomal sets, respectively. However, in Group 4, 53.3% of embryos showed abnormal ploidy (mixoploid). Although DMAP or combination with DMAP/CHX resulted in higher in vitro development of rabbit SCNT embryos, higher incidence of chromosomal abnormality may induce problems related to fetal loss of at late stage of development.

• Journal of Korean Neurosurgical Society
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• 제51권1호
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• pp.31-36
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• 2012

Objective : The purpose of this study was to elucidate the anatomical development of physiologic suture closure processes in infants using three dimensional reconstructed computed tomography (CT). Methods : A consecutive series of 243 infants under 12 months of age who underwent three dimensional CT were included in this study. Four major cranial sutures (sagittal, coronal, lambdoidal and metopic suture) were classified into four suture closure grades (grade 0=no closure along the whole length, grade 1=partial or intermittent closure, grade 2=complete closure with visible suture line, grade 3=complete fusion (ossification) without visible suture line), and measured for its closure degree (suture closure rates; defined as percentage of the length of closed suture line divided by the total length of suture line). Results : Suture closure grade under 12 months of age comprised of grade 0 (n=195, 80.2%), grade 1 (n=24, 9.9%) and grade 2 (n=24, 9.9%) in sagittal sutures, whereas in metopic sutures they were grade 0 (n=61, 25.1%), grade 1 (n=167, 68.7%), grade 2 (n=6, 24%) and grade 3 (n=9, 3.7%). Mean suture closure rates under 12 months of age was 58.8% in metopic sutures, followed by coronal (right : 43.8%, left : 41.1%), lambdoidal (right : 27.2%, left : 25.6%) and sagittal sutures (15.6%), respectively. Conclusion : These quantitative descriptions of cranial suture closure may help understand the process involved in the cranial development of Korean infants.