• Reproductive and Developmental Biology
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• 제37권1호
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• pp.35-40
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• 2013

The objective of this study was to investigate the effects of abnormal ovarian cycles after superovulation treatment of Holstein Donor Cows. CIDRs were inserted into the vaginas of twenty two head of Holstein cows, regardless of estrous cycle. Superovulation was induced using folliclar stimulating hormone (FSH). For artificial insemination, donor cows were injected with $PGF_2{\alpha}$ and estrus was checked about 48 hours after the injection. Then they were treated with 4 straws of semen 3 times, with 12-hour intervals. Embryos were collected by a non-surgical method 7 days after the first artificial insemination. The cows were considered to have resumed ovarian cyclicity on the day of ovulation if followed by regular ovarian cycles. Seventy two point seven percentage of the cows(16/22) had normal resumption of ovarian cyclicity(resumption within 40 days after superovulation), and 27.3%(6/22) had delayed resumption(resumption did not occur until>40 days after superovulation). Delayed resumption Type II(first ovulation did not occur until ${\geq}40$ days after superovulation, i.e. delayed first ovulation 13.6%) were the most common types of delayed resumptions. The mean numbers of total ova from < 10 and $10{\leq}$ of corpora lutea(CL) was $7.8{\pm}1.8$ and $12.7{\pm}2.7$, respectively. The number of transferable embryos differed between < 10 and $10{\leq}$ CL was $5.4{\pm}1.3$ and $8.1{\pm}3.4$, respectively. Four point five percentage of the cows(1/22) did not resumption their ovarian cyclicity until 60 days after superovulation treatment. Diverse researches on the superovulation treatment method that is suitable for high-producing Holstein donor cows would contribute to preventing ovarian cyclicity disorder, as well as to the early multiplication of cows with superior genes by increasing the utilization value of donor cows.

• Clinical and Experimental Reproductive Medicine
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• 제28권2호
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• pp.121-129
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• 2001

Objective: The aim of this study is to compare the efficiency of a method for the cryopreservation of mouse blastocyst.. Methods: Mouse embryos were obtained at 2-cell stage and cultured to blastocyst stage in T6 medium supplemented with 10% fetal bovine serum. Morphologically normal blastocysts were collected and randomly divided to one control and four experimental groups. In control group, blastocysts were cultured in vitro continuously for additional two days. In group 2, blastocysts were exposed to vitrification solution (ethylene glycol) only without cryopreservation (exposure only group). In group 3, 4 and 5, blastocysts were cryopreserved by slow-freezing procedure with glycerol (slow-fteezing group) or by vitrification procedure using EM grids (EM grids group) and cryoloop (cryoloop group), respectively. Frozen blastocysts were thawed and cultured for additional two days. Twenty four hours after thawing, some blastocysts were fixed and stained with Hoechst 33342 (bisbenzimide) and the number of nuclei in each blastocysts were counted to confirm the survival of bias to cysts in experimental groups. Results: Survival rate and hatching rate of the blastocysts in slow-freezing group (24 h: 72.4% and 66.0%, 48 h: 63.2% and 64.6%) and EM grids group (24 h: survival rate 77.3%, 48 h: 70.1% and 71.4%) were significantly lower ($X^2$-test p<0.05) than those of control group (24 h: 93.4% and 86.0%, 48 h: 88.5% and 90.7%). In contrast, the survival rate and hatching rate of the blastocysts in cryoloop group (24 h: 84.1% and 84.1%,48 h 79.3% and 87.7%) is well compared with those in the control group. The mean (${\pm}SD$) cell number of blastocyst in the exposure only ($89.2{\pm}11.5$), EM grids ($85.0{\pm}10.3$) and cryoloop ($89.0{\pm}11.0$) groups, except slow-freezing group ($79.0{\pm}10.0$), were not significantly different from that of control group ($93.1{\pm}13.9$) 24 h after thawing (Student's t-test). Conclusion: This study demonstrates that higher survival rate of vitrified-thawed mouse blastocyst can be obtained using cryoloop as the embryo container at freezing rather than slow-freezing or vitrification using EM grids. The results of this study suggest that vitrification using cryoloop (with ethylene glycol) may be a preferable procedure for mouse blastocyst cryopreservation and could be applied to the human blastocyst cryopreservation.

• Environmental Analysis Health and Toxicology
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• 제6권1_2호
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• pp.71-82
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• 1991

포유동물의 최기형성을 연구하는데 가장 많이 사용되는 동물인 설치류중 랫트의 배자를 이용하여, egg-cylinder기를 지나 head-fold가 이루어지는 초기체절기인 9.5일경부터 뇌, 눈, 귀, 심혈관계가 형성되는 시기인 11,5일까지 2일(48시간) 동안, 체외에서 배양하였다. 그 배양의 최적조건은 실험실마다 다르기 때문에 최적조건확립을 목적으로 이 실험을 행하였다. 온도는 37$^{\circ}C$$\pm$0.2$^{\circ}C$로 유지시키고 가스는 배양초기인 9.5일~10.5일 동안을 50%$O_2$, 5% $CO_2$, 90% $N_2$가스를 공급하여 10.5일부터 6시간 동안은 20% $O_2$, 5% $CO_2$, 75% $N_2$로 하며 나머지 18시간 동안은 40% $O_2$, 5% $CO_2$, 55% $N_2$가스를 배양계에 공급했을 때 가장 좋은 결과가 나왔다. 배양배지로서는 랫트 IC 혈청을 분리하여 열비동화시켜서 사용하였다. 이종혈청이나 합성배지를 첨가해서 배양할 경우는 랫트 혈청에 비해 성장이 좋지 않은 것으로 관찰되었다. 동물실험법의 대체법으로서 배자배양법의 기본조건을 확립하여 최기형성 평가 방법으로서의 가능성을 제시하였다.

• 의료법학
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• 제12권2호
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• pp.219-263
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• 2011

"Wrongful conception" is a medical malpractice claim in which the plaintiff is the parent of a normal, healthy infant whose conception was unplanned and unwanted. Medical malpractice in wrongful conception can be the result of a failure to provide informed consent to a patient, failure to properly perform a surgery, or a physician's negligent handling of a patient's problems. In the concrete, wrongful conception cases fall into two categories; those involving pre-conception negligence, such as a failed contraceptive, sterilization or failing of the controlling of embryo-number on the IVF, and those involving post-conception negligence, such as a failure to diagnose a pregnancy or to perform an abortion procedure. In addition, Medical malpractice can be the result of a failure to provide informed consent to a patient. When bad results occur by medical malpractice or failure to provide informed consent to a patient, the range of recovery of damages is decided by a traditional civil liability law. However the calculation of damages for wrongful conception is not easy because the high value of life is included in that case. So many courts opinions in foreign country and Seoul High Court decision in 1996 allow damages for the pregnancy, birthing process and sterilization costs, but refuses to allow damages for child rearing expenses. As to the range of recovery of damages for wrongful conception, one approach says that to allow damages in a suit such as this would mean that the physician would have to pay for the fun, joy and affection which plaintiff will have in the rearing and educating of the plaintiff's baby. To allow such damages would be against the dignity of the baby based on article 10 of the Constitution. However another approach says that damages are recoverable for all expenses related to child birth as well as for child rearing costs. Because the damages that the parents should bear a burden to the tort damage done is not a baby itself but child rearing costs. In other words, although the baby is healthy or not, economic burden of the parents can not be disregard. And denial of compensation for costs of child rearing may invalidate the role of liability law, grant the physician with a exemption certificate of liability. As a result, the medical field of procreation can be easily isolated from a liability of reparation. Therefore, on the liability law like the other medical malpractice action, parents who became pregnant or gave a birth by physician, wrongfully performed sterilization operation, etc. should be compensated for all damages relevant to unplanned and unwanted conception or birth as well as costs of child rearing.

• 생명과학회지
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• 제8권5호
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• pp.479-485
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• 1998

Xenopus 수정란의 동물극분리편에 IGF-1(Insulin-like Growth Factor-1)을 고농도로 처리해 주었을 때의 기관유도효과를 실험하였다. Activin A는 동물극 분리배양조직으로부터 다양한 기관을 분화시키며 이러한 효과는 처리 시간과 농도에 의존한다. 본 연구에서는 activin A 뿐만 아니라 IGF-1을 복합처리하여 특정 기관의 분화양상을 관찰하였다. Activin A는 100ng/ml 의 농도로, IGF-1은 0-500 ng/ml의 범위로 조합 처리하였다. 분리편은 정상배가 st. 43에 이를 때까지 배양하였으며, 이때 activin A를 100ng/ml의 고농도로 처리하면 조직이 파괴되는 것이 일반적이다. 그리고 신관의 발생에 대해서는 activin A와 retinoic acid의 복합처리가 매우 효과적인 방법으로 알려져 있으나, IGF-1의 첨가에 의해 신관을 비롯한 다른 조직들이 분화되었다. 또한, 눈의 분화는 activin A 1-100ng/m1와 IGF-1 500ng/ml의 농도범위에서 일어났다. Activin A의 저농도 (1ng/ml)처리에서는 혈구양세포가 분화하고 배양조직은 풍선처럼 부풀게되나 IGF-1의 첨가로 눈이 발생하게 되어 activin A상의 눈의 발생농도범위가 확대되었다.

• 한국식품과학회지
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• 제38권4호
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• pp.562-566
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• 2006

본 연구는 거대배아미 급여가 당뇨모델의 지질대사에 미치는 영향을 검토하고자 수행되었다. 실험모델은 스트렙토조토신으로 유발된 인슐린 의존형 당뇨 흰쥐를 이용하여, 실험식이를 6주간 급여한 후의 체내 지질함량 및 대변으로의 배설량을 각각 조사 하였다 거대배아미를 급여한 경우에는 당뇨가 유발되었음에도 불구하고 체중 증가의 현상이 나타났고, 장기 비대 현상은 억제 되고 있었다. 혈청 중성지방 몇 간의 총 콜레스테롤 함량도 현미 및 거대배아미 급여군에서 억제효과가 있었다. 그리고 대변으로 배설되는 총지질 및 콜레스테롤의 양도 거대배아미 급여군에서 대조군보다 유의하게 많은 것으로 나타났다. 이상의 결과들로부터 거대배아미 식이는 인슐린 의존형 당뇨쥐에서 대변중의 총 지질 및 총 콜레스테롤 배설량의 증가와 연관지어 당뇨병 모델의 체내 지질대사에 개선효과가 있음을 알 수 있다.

• 한국어류학회지
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• 제22권1호
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• pp.25-33
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• 2010

광염성 송사리 Oryzias dancena를 대상으로 서로 다른 염분도 조건이 산란, 발생 및 초기 생존 형질에 미치는 영향을 평가하고자 하였다. 송사리는 본 연구에서 설정한 모든 염분도 조건 (0~70$^{\circ}/_{\circ\circ}$)에서 산란이 가능하였으나 암컷의 산란 참여 빈도 및 산란 주기는 염분도 별로 차이가 관찰되어 담수 (0$^{\circ}/_{\circ\circ}$) 및 70$^{\circ}/_{\circ\circ}$에서 다른 염분도 그룹 (10~50$^{\circ}/_{\circ\circ}$)에 비해 낮은 값을 나타내었다. 조사한 염분도 조건 중 0~30$^{\circ}/_{\circ\circ}$ 구간에서만 수정률의 저하가 없었으며 염분도가 그 이상 높아질 경우 수정률의 유의적인 감소가 관찰되었다. O. dancena 수정란은 본 연구의 0, 15, 30, 45 및 60$^{\circ}/_{\circ\circ}$ 부화조건에서 모두 발생이 가능하였으나 염분도가 상승 할수록 배(embryo)의 생존율과 부화율이 저하되는 경향을 나타내었고, 특히 고염분의 조건에서는 기형 유발과 부화의 지연이 관찰되었다. 부화 자어 대상으로 다양한 염분도 조건에서 부화 후 7 일째까지의 초기 생존율을 관찰한 결과, 45$^{\circ}/_{\circ\circ}$ 이상의 염분도에서 초기 발달 과정 중 유의적인 폐사가 관찰되었으나 이후 안정화되는 경향을 나타내었다.

• 식물조직배양학회지
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• 제24권4호
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• pp.239-256
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• 1997

Plants belonging to the category of 2n apomixis or agamospermy form embryos and seeds without the processes of normal meiosis and syngamy. Seeds produced in this way have identical genotype of their maternal parent. Three different types of agamospermy are recognized: diplospory, apospory, and adventitious (adventive) embryony. $F_1$ hybrid cultivars cannot be used as seed sources in the next ($F_2$) generation because this generation would be extremely variable as a result of genetic segregation. Hybrid vigor is also reduced in the $F_2$ generation. Therefore, parental stocks for hybrid seed production need to be maintained and cross must be continuously repeated. Agamospermic 2n apomixis would make it possible to fix the genotype of a superior variety so that clonal seeds faithfully representing that genotype could be continuously and cheaply produced independent of pollination. That is, $F_1$ hybrid seeds could be produced for many generations without loss of vigor or genotype alteration. Production of apomictic $F_1$ hybrid seed would be simplified because line isolation would not be necessary to produce seed or to maintain parental lines, and the use of male-sterile lines could be avoided. Overall, apomixis would enable a significant reduction in hybrid seed production costs. Additionally, the production of clonal seed is not only important for seed propagated crops, but also for the propagation of heterozygous fruit trees and timbers. Clonal seed would help avoid costly and time-consuming vegetative propagating methods that are currently used to ensure the large-scale production of these plants. Apomixis is scattered throughout the plant kingdom, but few important agricultural crops possess this trait Therefore, most research to date has centered on introgressing the trait of apomixis into agricultural crops such as wheat, maize, and some forage grasses from wild distant relatives by traditional cross breeding. The classical breeding approach, however is slow and often impeded by many breeding barriers. These problems could be surmounted by taking mutagenesis or molecular approach. Arabidopsis thaliana is a tiny sexually reproducing plant and is convenient in constructing and screening in molecular researches. Male-sterile mutants of Arabidopsis are particularly suitable genetic background for mutagenesis and screening for apomictic mutants. Molecular approaches towards isolating the genes controlling the apomictic process are feasible. Direct isolation of genes conferring apomixis development would greatly facilitate the transfer of this trait to wide variety of crops. Such studies are now in progress.

• 대한수의학회지
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• 제55권2호
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• pp.133-139
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• 2015

The increasing uses of zinc oxide nanoparticles (nZnO) in industrial and personal care products raise possible danger of using nZnO in human. To determine whether ZnO induces size-dependent anomalies during embryonic organogenesis, mouse embryos on embryonic day 8.5 were cultured for 2 days under 50, 100, and $150{\mu}g$ of nZnO (< 100 nm) or micro-sized ZnO (mZnO; $80{\pm}25{\mu}m$), after which the morphological changes, cumulative quantity of Zn particles, and expressions of antioxidant and apoptotic genes were investigated. Although embryos exposed to $50{\mu}g$ of ZnO exhibited no defects on organogenesis, embryos exposed to over $100{\mu}g$ of ZnO showed increasing anomalies. Embryos treated with $150{\mu}g$ of nZnO revealed significant changes in Zn absorption level and morphological parameters including yolk sac diameter, head length, flexion, hindbrain, forebrain, branchial bars, maxillary process, mandibular process, forelimb, and total score compared to the same dose of mZnO-treated embryos. Furthermore, CuZn-superoxide dismutase, cytoplasmic glutathione peroxidase (GPx) and phospholipid hydroperoxidase GPx mRNA levels were significantly decreased, but caspase-3 mRNA level was greatly increased in nZnO-treated embryos as compared to normal control embryos. These findings indicate that nZnO has severer teratogenic effects than mZnO in developing embryos.

• 한국발생생물학회지:발생과생식
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• 제13권4호
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• pp.305-312
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• 2009

단분화성 정원줄기세포의 장기간 체외배양 중에 확립되는 다분화능 정원줄기세포는 배아줄기세포와 유사한 특성을 가져 3배엽성 세포로 체외분화가 가능하며 기형종을 형성할 수 있다. 본 연구에서는 선행 연구를 통해 outbred 생쥐(ICR strain)로부터 확립된 다분화능 정원줄기세포의 형질전환 가능성을 확인하며, 배아 내로 주입하여 유전적 키메라를 형성하는 효율을 배아줄기세포와의 비교를 통하여 검증하고자 하였다. 다분화능 정원줄기세포를 넣은 배아로부터 태어난 산자는 총 47마리(4.8%)가 태어나, 67마리(11.7%)가 태어난 배아줄기세포군에 비해 그 효율이 낮았다(P<0.05). 그러나 산자들 중의 키메라 생쥐의 비율은 다분화능 정원줄기세포 군으로 부터 3마리(6.4%)가 태어나 배아줄기세포 군으로부터 태어난 5마리(7.5%)와 유사하였다(P>0.05). 태어난 유전자변형 생쥐의 장기를 확인한 결과, 췌장, 심장, 뇌, 근육, 위, 피부, 정소에 GFP가 발현되는 것을 확인하였다. 또한 배아의 근육, 위, 뼈 등에서 anti-GFP 항체의 발현을 확인하였다. 이상의 결과를 종합하면 outbred 생쥐로부터 확립된 다분화능 정원줄기세포가 inbred 생쥐로부터 확립된 배아줄기세포와 마찬가지로 키메라 생쥐를 생산할 수 있는 전분화능을 가짐을 확인하였고, 새로운 유전자변형 동물의 생산을 위한 매개체로서의 가능성을 가진 것으로 여겨진다.