• Title/Summary/Keyword: 체외 수정

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Studies on the Improvement of Performance and Reproductive Efficiency in Farm Animals I. In vitro fertilization by in vitro capacitated sperm and transfer of in vitro fertilized embryos in rabbits (가축의 개량 및 번식효율 증진에 관한 연구 I. 토끼에 있어서 체외수정능획득 정자에 의한 체외수정 및 수정란 번식에 관한 연구)

  • 정영채;김창근;주일영;정길생;이규승
    • Korean Journal of Animal Reproduction
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    • v.10 no.2
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    • pp.192-203
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    • 1986
  • Two experiments in this study were designed to compare the potential for in vitro capacitation and in vitro fertilization of ejaculated sperm among individual rabbit bucks. In experiment 1, for in vitro capacitation, the ejaculated sperm were preincubated in DM for 12 hr or 18 hr after HIS treatment, then 12 hr -or 18 hr- preincubated sperm were incubated with superovulated rabbit ova in a 5% CO2 incubator for 36 hr at 38$^{\circ}C$, and a part of cleaved ova was transferred to the recipient does for implantation of embryo. In experiment 2, effect of lysolecithin addition to preincubation medium on induction of accelerated in vitro capacitation and in vitro fertilization of individual rabbit sperm was studied. Experiment 1; 1. Percent acrosome reaction of sperm, noted after staining, after 12 hr or 18 hr preincubation ranged from 52.5 to 76.0% and from 67.5 to 90.0%, respectively and sperm motility index of these sperm ranged from 20.0 to 47.5 for 12 hr-preincubated sperm and from 15.0 to 37.5 for 18 hr- preincubated sperm. There was no a certain relation between percent acrosome reaction and sperm motility index. 2. In vitro fertilization rate (cleavage rate) of in vitro capacitated sperm varied widely among individual bucks, ranging from 0 to 47.8% for 12 hr - preincubated sperm and from 0 to 60.9% for 18 hr -prein- cubated sperm. Cleavage rate of 18 hr - preincubated sperm was higher and faster than that of 12 hr - preincubated sperm. 3. Eight of 44 in vitro fertilized embryos transferred into 6 recipients were implanted in 4 recipients (66.7%) up to day 15 and implnatation rate was 18.2%. Experiment 2; 1. The percent acrosome reaction of sperm before and after 4 hr preincubation in DM without lysolecithin varied significantly among individual bucks, ranging from 0.4 to 18.4% and from 1.7 to 37.4%, respectively and percent acrosome reaction of sperm at 30 min after addition of 60${\mu}$g/ml lysolecithin also was significantly different among bucks, ranging from 19.2 to 67.1%. 2. Effect of accelerated acrosome reaction following lysolecithin addition was more considerable in the individuals showed less percent acrosome reaction before and after 4 hr preincubation. Percentage of motile sperm and motility score showed a trendency towards a decrease with increase of preincubation time and time after lysolecithin addition. 3. In vitro fertilization rate (cleavage rate) at 24 hr postinesmination with pooled sperm were treated to 60 $\mu\textrm{g}$/ml lysolecithin for 30 min after 4 hr preincubation was 24.6%, a higher rate than 13.2% for control. While 80 $\mu\textrm{g}$/ml lysolecithin-added sperm showed a lower cleavage than control and 60$\mu\textrm{g}$/ml-added sperm at both 24 hr and 48 hr postinsemination. These results from 2 experiments suggest that more useful preincubation time for the in vitro capacitation of ejaculated rabbit sperm is 18 hr in DM after HIS treatment, although there is wide variation in vitro capacitation and in vitro fertilization rate among individual bucks, and lysolecithin addition to at least 4 hr - preincubated sperm in DM can result in almost same in vitro fertilization rate as that of 18 hr - preincubated sperm in the experiment 1.

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Effects of GnRH Agonist Administered to Mouse on Apoptosis in Ovary and Production of Estradiol and Progesterone (생쥐 내로 투여된 GnRH Agonist가 난소내 세포자연사와 Estradiol 및 Progesterone 합성에 미치는 영향)

  • Hong Soonjung;Yang Hyunwon;Kim Mi-Ran;Lee Chi-Hyeong;Hwang Kyung-Joo;Kwon Hyuck-Chan;Yoon Yong-Dal
    • Development and Reproduction
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    • v.7 no.1
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    • pp.49-56
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    • 2003
  • There have been reports that administrated high-dose gonadotropin-releasing hormone-agonist(GnRH-Ag) suppresses endogenous gonadotropin production and inhibits function of ovary. In human IVF-ET program, however, GnRH-Ag is employed in large amounts during superovulation induction resulting to luteal phase defects which must be supported with progesterone. To elucidate the reason of luteal phase defects by GnRH-Ag, the aim of this study was to investigate the apoptosis changes in the ovary and the hormonal changes in the serum after GnRH-Ag and PMSG administration in adult mice in a method similar to human superovualtion induction. GnRH-Ag(10 ${\mu}$g) or saline was injected every 12h beginning 48h prior to PMSG injection until 48h at)or PMSG injection when blood sampling and ovary collection was performed. In results, the ovary weight in the GnRH-Ag only injection group was significantly lower when compared with the other two groups, PMSG only or PMSC + GnRH-Ag injection. The ratio of preantral follicles in the ovary are increased in the GnRH-Ag only group, while the ratio of antral follicles are decreased and the corpus luteum ratio is increased in the PMSG + GnRH-Ag group. The proportion of all follicles showing apoptosis in the GnRH-Ag only in.iection group was seen to be more than twice the proportion seen in the PMSC only injection group, and such increased apoptosis is decreased after addition of PMSC. The serum levels of both estradiol and progesterone were significantly lower in the CnRH-hg only group compared to those in the other two groups. When the administration of GnRH-Ag were followed by PMSG in;ection, however, estradiol concentration was completely recovered compared to the serum level of PMSG group, but not progesterone level. In conclusion the use of GnRH-Ag in human IVF-ET program may induce the apoptosis and the suppression of hormone production by ovary leading to luteal phase defects, thus adequate progesterone support seems to be necessary against them.

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Cryopreservation of Mouse IVF Zygotes by Vitrification (체외수정된 생쥐 1-세포기 배의 초자화 동결)

  • 김묘경;이현숙;엄상준;김은영;윤산현;박세필;정길생;임진호
    • Korean Journal of Animal Reproduction
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    • v.20 no.2
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    • pp.119-126
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    • 1996
  • This study was carried out to determine the optimal condition for successful and efficient c cryopreservation of zygotes, 1-cell embryos, using EFS40 which was 40% (v/v) ethylene glycol diluted in DPBS medium containing 30% Fic-oll (w/v) and 0.3 M sucrose. After mouse zygote produced by IVF was vitrified by two freezing methods, the post-warming survival rates of 1-cell zygotes were assessed as cleavage to the 2-cell stage and development into the hatching blastocysts at 5 day. In the one-step method, when embryos were directly exposed to the vitrification solution at 25$^{\circ}C$ for 1 min., survival and development rates of zygotes were 85.5% and 31.9% In the two-step method, embryos were equilibrated with a dilute 20% EG for 1, 3, 5 min. before 1 min. exposure to EFS40, re-spectively. However, the rates of development (17.7, 3.3, 0%) were lower than that of one-step method. The highest survival rate (95.9%) was obtained by one-step method which exposes embryos in EFS40 for 30 sec. In this condition, 63. 8% of cleaved 2-cell developed into hatching blastocysts. In the cell number of Total and ICM using differential labelling technique, there are no significant differences in the cell number of Total and ICM between blastocysts devel oped in vitrified-thawed embryos (63.2${\pm}$16.9, 1 13.5${\pm}$4.0) and control balstocysts (54.0${\pm}$15.2, 1 12.3${\pm}$4.6). Therefore, these results show that mouse zygotes can be successfully cryopreserved by a simple vitrification method although developmental rates of vitrified embryos were reduced. In conclusion, this proposed vitrifi cation procedures can be useful in the cryopreservation of mouse IVF zygotes.

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Characteristics of Ginseng Extract and Its Effects on Sensory Properties of Pork Sausage (인삼 추출물의 사포닌 조성 특성과 추출물 첨가가 포크소시지 관능 특성에 미치는 영향)

  • Park, Kyoung-Mi;Hwang, In-Ho
    • Food Science of Animal Resources
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    • v.26 no.4
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    • pp.418-425
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    • 2006
  • This study was conducted to evaluate extraction properties of crude saponin and ginsenosides, and their effects on sensory properties of emulsified pork sausage. Non-dried ginseng root was boiled in 0 (e.g., 100% distilled water), 20, 40, 60, 80 or 100% ethanol, and powdered by a freezing dry method. Weight of dried powder for the 0% ethanol extraction was 20% of initial non-dried ginseng weight, while $20{\sim}80%$ and 100% ethanol extractions resulted in approximately 15 and 10% of their initial weights, respectively. On the other hand, crude saponin content in the dried powder was linearly increased for a higher ethanol content where 100% ethanol extraction resulted in 123.52 mg/g. LC/MS analysis of crude saponin for quantifying ginsenosides showed that Rb1, Rb2 and Rc were significantly (p<0.05) higher levels for both 80 and 100% ethanol extractions. In the case of Rg1 ginsenoside, 60, 80 and 100% ethanol extractions resulted in significantly (p<0.05) higher levels. Emulsified pork sausages containing 0, 1 or 2% ginseng extracts were smoked or non-smoked and their sensory characteristics and preference were evaluated. Smoking process significantly (p<0.05) decreased juiciness and tenderness, but the treatment significantly (p<0.05) improved flavor and consumer preference. It was particularly noticed that a 2% addition of ginseng extract prevented the adverse effects of smoking process on juiciness and tenderness while the 2% addition significantly (p<0.05) improved consumer preference. The current results implied that addition of ginseng extract in emulsified pork sausage could improve sensory quality.

Effects of Ferrous Sulfate and Ascorbic Acid on In Vitro Fertility and Sperm Lipid Peroxidation in the Pig (돼지의 체외수정능력과 정자의 Lipid Peroxidation에 있어서 Ascorbic Acid와 Ferrous Sulfate의 영향)

  • Park, C. K.;J. Y. Ann;Kim, I. C.;Lee, J. H.;B. K. Yang;Kim, C. I.;H. T. Cheong
    • Korean Journal of Animal Reproduction
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    • v.25 no.4
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    • pp.317-325
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    • 2001
  • This study investigated the effect of ferrous sulfate (Fe$^{2+}$) and/or ascorbic acid (Asc) on fertilizing ability in vitro of frozen-thawed boar spermatozoa. Using chlortetracycline (CTC) fluorescence, the spermatozoa was treated in preincubation medium with control, Fe$^{2+}$(1 mM), Asc (0.5 mM) and Fe$^{2+}$Asc to assessed for acrosome reaction, and the oocyte penetration test to determine whether the Fe$^{2+}$ and/or Asc can promote the penetration ability in vitro. When frozen-thawed spermatozoa was washed with preincubation medium, there were significantly (P < 0.05) more acrosome-reacted in medium with Fe$^{2+}$Asc (38%) than control (27%). The penetration rates were also significantly (P < 0.05) higher in medium with Fe$^{2+}$Asc (76%) than control (55%). Next, the lipid peroxidation of sperm was evaluated on the basis of malondialdehyde production following same treatments. The addition of Fe$^{2+}$Asc to sperm suspension increases the formation of malondialdehyde. However, there were not significantly different under the all conditions. The sperm suspension were also treated with control, Fe$^{2+}$, Asc and Fe$^{2+}$/Asc and assayed for sulfhydry1(-SH) group content. In the Fe$^{2+}$/Asc group, sperm-SH group were higher than another groups. In spermatozoa treated with Fe$^{2+}$ and/or Asc, however, no changes in sperm -SH-groups were detected when compared to controls. In another experiment, the activity of sperm binding to zona pellucida was evaluated through binding to salt-stored porcine oocytes. In control and Asc treatment groups, sperm binding to zona pellucida were significantly (P < 0.05) higher than in medium with Fe$^{2+}$. On the other hand, there is not a significant increase in binding to zona pellucida with spermatozoa treated by Fe$^{2+}$/Asc. In summary, the present study suggests that Fe$^{2+}$/Asc causes an enhancement in fertilizing ability that is associated with penetration rate increased without change of spermatozoa binding capacity to homologous zona pellucida.o homologous zona pellucida.

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Effect of Fragment Removal on Development of Human Fragmented Embryos in IVF-ET Program (IVF-ET 시술 시 파편제거가 파편화된 인간배아의 발달에 미치는 효과)

  • Chi, Hee-Jun;Koo, Jung-Jin;Lee, Ju-Ok;Ryu, Hyoung-Eun;Kim, Kwang-Rae;Park, Chan;Roh, Sung-Il
    • Clinical and Experimental Reproductive Medicine
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    • v.37 no.4
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    • pp.339-348
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    • 2010
  • Objective: To investigate the beneficial effect of fragment removal on the subsequent cell division and clinical outcome of the fragmented human embryos. Methods: A prospective study was performed in Hanna Women's Clinic and Mizmedi Hospital. Sixty couples undergoing In vitro fertilization-embryo transfer (IVF-ET) program were participated in the present study. The microsurgical fragment removal was performed in 106 fragmented embryos of 29 patients before the transfer. As a control group, 122 fragmented embryos of 31 patients were transferred without the fragment removal. Effects of fragment removal on morphological changes and clinical outcomes of fragmented embryos were investigated. Results: Mean morphological grade (G2.79) of fragmented embryos was significantly improved after the fragment removal(G1.63, p<0.001). Most of the fragmented embryos did not show a regeneration of fragments after the fragment removal during the subsequent development, and a beneficial effect of fragment removal on the development of the fragment removed embryos was observed. Implantation and pregnancy rates of fragment removed embryos were 12.3% and 31.3%, whereas the rates of control group embryos were 6.6% and 22.5%, respectively. There was no statistical significance in the rates between the two groups because of the low number of trials. Conclusion: Microsurgical fragment removal improved the subsequent development as well as the morphological grade of fragmented embryos. The fragment removal may be beneficial for neighboring blastomeres by repairing the intercellular communication and removing the secretion of the potential toxic materials by fragments.

Preselection of Bovine Blastocysts Expressing Exogeneous Gene Following Microinjection (외래유전자를 주입한 소 수정란에서 형질전환가능 수정란의 선발)

  • 공일근
    • Korean Journal of Animal Reproduction
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    • v.21 no.2
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    • pp.167-176
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    • 1997
  • This study was carried out to evaluate the potential for preselection of transgenic embryos prior to transfer into recipient animals. In these experiments, I used a 3.2 kb transgene which contained the neomycin resistance gene (neo) and lac Z gene driven by the $\beta$ actin promoter (iacZ Ineo). Oocytes were aspirated from abattoir ovaries, matured in TCM-199 supplemented with 10% fetal bovine serum (FBS), 5 ${\mu}\textrm{g}$/ml LH, 0.5 ${\mu}\textrm{g}$/ml FSH, 100 unit/ml penicillin, and 100 ${\mu}\textrm{g}$/ml streptomycin for 22 to 24 hrs then inseminated with a sperm suspension of 1 X 10$^6$ sperm/ml containing 5 ${\mu}\textrm{g}$/ml of heparin. At 18-20 hrs after insemination, cumulus cells were removed by vortexing and pronuclei of centrifuged zygotes microinjected with the lacZ/neo construct (3 ng/$\mu$l). All cultures were carried out in CR1aa with transfected BRL monolayers containing 3 mg/ml BSA, 20 $\mu$/ml NEM amino acids and 40 $\mu$I/ml BME amino acids. To identify the appropriate concentration of G418 for selection, non-microinjected zygotes were cultured in the presence of 0, 50, 100 and 200 $\mu$g/ml of G418. After 8 days of culture in these treatments, 44/145 (30.3%), 13/150 (8. 7%), 1/151 (0.7%) and 0/134 (0.0%) devel-oped to the blastocyst stage in 0, 50, 100 and 200 $\mu$g/ml of G418, respectively. A total of 1,127 zygotes were microinjected and placed into culture (without G418) and subsequently 710 (63.0%) cleaved. At 48 hrs post-injection, embryos ($\geq$2-cell) were randomly assigned to control (medium alone) or G418 (100 ${\mu}\textrm{g}$/ml) treatments. A control culture of 740 non-microinjected embryos from the same replicates of embryos were also placed into control medium. After 8 days in culture, 54/343 (15.7%) and 22/367 (6.0 %) of the microinjected embryos developed to the blastocyst stage in control and G418 media, respectively. A total of 151/740 (27.2%) of the non-microinjected embryos placed in the control medium developed to the blastocyst stage. The blastocysts in the control treatment had a mean of 70.7 ${\pm}$ 4.7 cells of which 23.1 ${\pm}$ 2.6 (32.7%) stained for $\beta$-Gal activity. B1astocysts in the G418 treatment had a mean of 48.8${\pm}$7.5 cells of which 40.3 ${\pm}$ 4.1 (82.6%) stained for $\beta$-Gal ac tivity (P<0.05). In the control treatment 26 of 30 (87.0%) blastocysts had some cells with $\beta$-Gal activity while all of the blastocysts in the G418 treatment had some cell with $\beta$-Gal ac tivity (P<0.05). However, ICM colonies in either control or G418 treatments were not expressed any epiblast cell except of trophetoderm celIs. The $\beta$-actin promoter/lacZ gene may not be e expression or silence expression in epiblast cells These results clearly show an enrichment of blastocysts expressing the transgene in the majority of their cells after culture in the presence of G418. The exogeneous gene was not express a and silence in ICM colonies especiallly epiblast cells except of trophectederm cells. Even though the higher rate cell number expressed of exogeneous gene in the G418 treatments, a total cell number was decrease significantly (P<0.05) of which might be also drop of the establishment of ES like-cell colonies and production of transgenic animals. However, futher studies need to determine the viability of these selected embryos and the avability of production of transgenic offspring.

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Improvement of Straw Loading Method on Survival of Mouse IVF/IVC Blastocysts Cryopreserved by Vitrification (체외수정과 체외배양에서 생산된 생쥐 배반포기배의 초자화 동결에 있어서 Straw Loading 방법의 개선)

  • 김선의;엄상준;김은영;윤산현;박세필;임진호
    • Korean Journal of Animal Reproduction
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    • v.20 no.1
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    • pp.35-42
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    • 1996
  • This study was carried out to investigate the effect of straw loading method and thawing protocol on the in vitro development of in vitro produced mouse blastocysts cryopreserved by vitrification. Three loading types of straw I, Il and III on loading and sealing method were made for vitrification. The ability of the solution on straw loading methods to remain vitreous during warming was tested by exposed in air for 1 to 10 s sec. and then plunged the vitrified straws into water bath at 25°C. Embryos to be vitrified were equilibrated to the 20% EG for 5min. and exposed in EFS 40 for 1min. The plug ends of Straw I and Straw II were sealed with straw powder and Straw III was treated straw powder, followed by heat sealing and then plunged into LN$_2$. The results obtained in these experiments were summarized as follows; 1) Straw I embryo column mostly changed from transparent to opaque upon thawing without exposure in air for 3-6 sec. Straw II embryo column was I improved partially but was not remained completely vitreous during warming. However, when Straw lll loading method was used, the embryo column was remained vitreous completely. 2) High survival rates and development rates of each groups (middle blastocysts and hatching blastocysts) of vitrified embryos were obtained by using Straw III loading method than Straw I method (P<0.05). And the range of s standard error was low in Straw lll method. 3) When the embryos vitrified-frozen were placed in air for 3, 5 and l0sec. and then warmed rapidly in water bath at 25$^{\circ}C$, the survival rates after 24h of culture were 72.7-87.1% and the development rates to hatching stage after 48h of culture were 34.0-48.4%. There were no significantly differences according to exposure time in air during warming. In conclusion, the present results showed that highly survival and low standard error of vitrified-frozen mouse bIastocysts were obtained by using straw lll loading, double sealing and appropriate 2 step warming method.

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Experimental Fetal Cardiopulmonary Bypass in the Fetal Lamb Model (태아양 모델을 이용한 실험적 태아 심폐우회술)

  • 이정렬;임홍국;김원곤;김종성;최정연;김용진
    • Journal of Chest Surgery
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    • v.32 no.6
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    • pp.495-503
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    • 1999
  • Background: We tested the technical feasibility of fetal cardiac bypass and collected baseline data on the fetal hemodynamics and placental functions related to the cardiopulmonary bypass in the fetal lamb model. Material and Method: Eleven fetuses at 120 to 150 days of gestation were subjected to bypass via trans-sternal approach with a 12 G pulmonary arterial cannula and 14 to 18 F venous cannula for 30 minutes. All ewes received general anesthesia with ketamine. In all the fetuses, no anesthetic agents were used except muscle relaxant. Eight served as a group in which placenta was excluded from the extracorporeal circulation by clamping the umbilical cord during the bypass(the oxygenator group) and in the remaining three, the placenta worked as the only source of oxygen supply(the placenta group). Observations were made every 10 minute during a 30-minute bypass and 30-minute post bypass period. No prostaglandin inhibitors were used both in ewes and in fetuses. Result: Weights of the fetuses ranged from 1.9 to 5.2 kg. In the oxygenator group, means of arterial pressure, PaO2, atrial pressure, heart rate, and bypass flow rate ranged 69.8 to 82.6 mmHg, 201.7 to 220.9 mmHg, 4.1 to 4.3 mmHg, 169 to 182/min, and 140.3 to 164.0 ml/kg/min, respectively during bypass, but rapid deterioration of the fetal cardiac functions and the placental gas exchange was observed after the cessation of bypass. In the placenta group, means of arterial pressure decreased from 44.7 to 14.4 mmHg and means of PaCO2 increased from 61.9 to 129.6 mmHg during bypass. Flow rate was suboptimal(74.3 to 97.0 ml/kg/min) during bypass. All hearts fibrillated immediately after the discontinuation of bypass. Conclusion: In this study, the technical feasibility of fetal cardiopulmonary bypass was confirmed in the fetal lamb model. However, further studies with modifications of the bypass including an addition of prostaglandin inhibitor, an application of the total spinal anesthesia on the fetus, a creation of more concise bypass circuit, and a use of active pump are mandatory to improve the outcome.

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Effects of Equilibration and Dilution Methods on the Survival of Vitrified Bovine IVE Embryos (동결액의 평형방법과 희석방법이 초자화 동결된 소 체외수정란의 생존성에 미치는 영향)

  • 김정익;유재원;박춘근;양부근;정희태
    • Journal of Embryo Transfer
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    • v.13 no.3
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    • pp.313-321
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    • 1998
  • This study was conducted to investigate the effects of equilibration and dilution methods on the survival rate of vitrified IVM-IVF bovine blastocysts. Vitrification solution was composed with 20% glycerol, 20% ethylene glycol, 3/8 M sucrose and 3/8 M dextrose in D-PBS supplemented with 20% FBS (GESD). Embryos were equilibrated in 1 of 3 methods: 3-step (El), 2-step (E2), or 1-step (E3), and after loading into 0.25-ml straws, were plunged into liquid nitrogen. After warming in water bath at 2$0^{\circ}C$, cryoprotectants were diluted in 1 of 3 methods: 1) D1(VS+1/2 M sucrose, 1/2 M sucrose and l/4 M sucrose), 2) D2 (1/2 M sucrose and 1/4 M sucrose), or 3) D3(1/2 M sucrose only). All procedures except warming were conducted at room temperature. Survival and hatching rates of blastocysts and expanded blastocysts following equilibration methods were 50 and 83.6%, and 27.8 and 67.3%, respectively in El, which were significantly higher (P〈0.01) than those of E2 (16.7 and 23.2%, and 7.4 and 12.5%, respectively) and 23 (0 and 3.7%, and 0 and 0%, respectively). Survival and hatching rates of expanded blastocysts were significantly (P〈0.01) higher than those of blastocysts in El. Survival rates of blastocysts and expanded blastocysts following dilution methods were 52% and 80.6% in D2, which were significantly higher (P〈0.05) than those of D1 (29.6 and 48.3%) and D3 (47.2 and 63.8%). Hatching rates of blastocysts were similar in D1, D2 and D3, however in expanded blastocysts, that of D2(61.3%) was significantly higher (P〈0.01) than that of D1(34.5%). Survival rates of expanded blastocysts in D1 and D2, and hatching rates in D2 and D3 were significantly higher(P〈0.01) than those of blastocysts. These results indicate that the viability of vitrified blastocysts was improved by the several steps of equilibration, and by 2-steps dilution after warming, independently of their stage of development. The results also indicated that the expanded blastocysts are more profitable to vitrification than blastocysts.

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