• 한국수정란이식학회지
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• 제19권1호
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• pp.27-34
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• 2004

This study evaluated the efficiency and compared with different materials of loading vessels for vitrification-plastic/glass, copper grid and nylon. The loading method, vitrification, cryop-reservation and warming method of the oocytes were examined. The loading samples prepared in manual or company-made and sterilized, loaded the COCs selected on each samples and cultured for maturation during 40 hours, and then exposed sequentially to ethylene glycol solution. Thawing method was reversely treated and exposed for warmed oocytes. After oocytes were thawed, fertilized and cultured in vitro for 3-4 hours, rates of development and morphological appearance were examined. The results were as summarized: ㆍOPS from company-made or hand-made of the hematocrit micropipettes, NLS from fishing line and EMG from company-made for EM were used for loading oocytes, respectively. ㆍThe efficiency of freezing method and loading convenience were orderly higher in OPS, NLS and EMG. The optimal capacity per vessel was orderly lowered in NLS, EMG and OPS, respectively. ㆍAfter oocytes were warmed, the recovery rate, morphology and rate of development were orderly higher in OPS, NLS and EMG, respectively. ㆍIn conclusion, OPS has the advantages of achieving a little more survival and preserving results than other two loading methods.

• 한국통신학회논문지
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• 제39B권2호
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• pp.86-94
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• 2014

광 패킷 스위칭은 미래 광 인터넷을 위한 스위칭 기술로 고려되고 있다. 광 패킷 스위칭 내부의 경합 해결을 위해 파장 변환 기법이 광 지연 선로 버퍼와 함께 일반적으로 사용되어 진다. 본 논문에서는 공유형 혹은 아웃풋 광 지연 선로 버퍼를 갖는 비동기 광 패킷 스위칭 시스템의 비용 효율적인 설계를 위해 가변 파장 변환기를 공유함으로써 필요한 파장변환기 개수의 감소를 도출한다. 비동기 가변길이 패킷들을 비용 효율적 설계를 위해 고려하였고, 그러한 광 패킷 스위칭 시스템 내부에 필요한 가변 파장 변환기 개수를 도출하기 위해 출력 단의 채널뿐아니라 유용 가능한 가변 파장 변환기와 내부 파장 또한 찾아 주는 스케쥴링 알고리즘을 제안한다. 제안된 알고리즘을 공유형 혹은 아웃풋 광 지연 선로 버퍼를 갖는 비동기 광 패킷 스위칭 시스템에 적용하여 비용 효율적 설계를 위해 필요한 가변 파장 변환기 및 내부 파장 개수를 도출하였다.

• Reproductive and Developmental Biology
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• 제30권1호
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• pp.35-40
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• 2006

본 연구는 OPS 기법에 의한 돼지 수정란의 동결-융해 시 수정란의 발달 단계와 superoxide dismutase (SOD)가 수정란의 생존능력에 미치는 영향을 검토하였다. 돼지 체외수정 배반포는 OPS방법에 의해 동결 후 융해하여 $0{\sim}10units/ml$의 SOD 존재 하에 48시간 체외배양하였다. 동결-융해 후 형태학적으로 정상적인 수정란의 비율은 초기, 중기 및 확장배반포간에 유의적인 차이는 인정되지 않았다$(30.8{\sim}38.6%)$. 그러나 발육단계가 높을수록 형태적으로 정상인 수정란의 비율이 높은 경향을 나타냈다. 수정란의 융해 후 48시간 추가 배양했을 때, 발육이 진행된 수정란은 후기배반포기에 동결한 수정란이 38.7%로 유의적으로 높았으며(P<0.05), 1 unit/ml의 SOD를 첨가한 경우 비교적 높은 생존율을 나타내었다. 본 연구의 결과로부터, 수정란의 OPS방법에 의한 동결-융해 후 생존성의 향상을 위해서는 후기배반포기 단계에 동결하는 것이 유리하며, SOD의 첨가는 수정란의 손상을 어느 정도 방지할 수 있을 것으로 사료된다.

• 한국수정란이식학회지
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• 제23권3호
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• pp.217-222
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• 2008

In previous studies, we reported that sow which was transferred OPS-freezing embryos not able to deliver a piglet (Kim et al, 2004). This study was conducted to investigate a possibility of gilt as recipients which produce piglets after transfer of OPS-freezing embryos. All transferred embryos were prepared by in vitro production (IVP) system. In vitro culture (IVC) medium used glucose-free NCSU23 supplemented with 5mM sodium pyruvate, 0.5 mM sodium lactate and 4 mg/ml bovine serum albumin for 2 days at $39^{\circ}C$. From day 3 of IVC, 10% fetal bovine serum albumin was added to the culture medium. In preparing of freezing embryos, embryos were treated with 7.5 $\mu g/ml$ cytochalasin-B for 30 min and centrifuged at $13,000{\times}g$ for 13 min. And then, embryos were exposed sequentially to an ethylene glycol (EG) solution, aspirated into open pulled straw (OPS), and plunged or thawed into the liquid nitrogen. In embryo transfer (ET), we used two kinds of type (surgical method vs. non-surgical method). In surgical method of embryo transfer, $55\sim65$ embryo were transferred in both uterine horn of two recipient gilts by plastic straw. Non-surgical method which is like artificial insemination was performed on three gilts. Each 140 frozen embryos were transferred to two gilts and 40 fresh embryos to one gilt. Pregnancy establishment was shown one recipient at 45 days after ET. However, the one recipient was also aborted at 58 days after ET. These results suggest that gilts can be considered as a candidate of recipients for OPS-freezing embryo transfer.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2001년도 춘계학술발표대회
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• pp.76-76
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• 2001

The objective of this study was to optimize the vitrification method of in vitro produced bovine embryos. Thus, in vitro produced embryos at 8 cell, morula and blastocyst stages were vitrified on electron microscope grids (EM grids) or in open pulled straws (OPS) with EG5.5 (5.5 M ethylene glycol, 1.0 M sucrose and 10% FBS in m-DPBS medium) freezing solution and their survival rates after thawing were compared. The embryos on EM grids or in OPS were briefly exposed to EG5.5 freezing solution and plunged directly into liquid nitrogen within 30 to 35 sec. Post-thawed embryos were serially diluted in 0.5, 0.25 and 0.125 M sucrose in m-DPBS, each for 1 min, and then cultured in CRI aa medium supplemented with 10% FBS. Embryonic survival rate was assessed as re-expanded and hatched rates of those embryos after warming. The rates of re-expansion embryos did not significantly different between EM grid (8 cell: 42.10%, morula: 66.66% and blastocyst: 77.08%) and OPS (8 cell: 47.36%, morula: 61.90% and blastocyst: 83.33%) methods. In addition, the hatched rates in EM grid (8 cell: 31.57%, morula: 57.14% and blastocyst: 72.91%) were similar to those in OPS (8 cell. 34.21%, morula: 50.00% and Blastocyst: 77.08%). Interestingly, even at the same blastocyst stage, the in vitro survival of day 7 embryos (EM grid: 79.48 and OPS: 87.18%) was higher than those of day 8 embryos (EM grid: 72.10 and OPS: 82.06%). The total cell number of blastocyst developed in vitro after vitrification was examined with Hoechst 33342 staining to compare the embryo quality among different treatment groups. The total cell number of blastocyst was not significantly different between vitrified groups (EM grid: 162.4$\pm$8.0 and OPS: 158.4$\pm$7.1) and unvitrified control (168.0$\pm$5.6). These results indicate that both vitrification containers can provide the high rate of embryo survival. Moreover, the OPS container may not need a cap to protect the container from floating after immersion in L$N_2$. Therefore, this study suggest that bovine embryos can be cryopreserved easily, effectively and successfully by vitrification method using EM grid or OPS with EG5.5 freezing solution. In the future, the Pregnancy rate would be investigated after transfer of our vitrified embryos into the appropriated recipients.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2006년도 The 6th Intermational Symposium on Developmental Biotechnology
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• pp.113-113
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• 2006

• 한국가축번식학회지
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• 제23권4호
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• pp.313-321
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• 1999

본 연구는 체외생산된 배반포기배의 vitrification 을 위한 용기로서 glass micropipette(GMP)을 이용할 수 있는지, GMP 와 OPS 로 동결융해 후 생존율의 비교 및 GMP vitrification 후 hatching 율의 향상을 위하여 실시하였다. GMP vessel은 열전도율과 수정란을 포함하는 적은 질량 때문에 OPS 보다 동결 및 융해속도를 높일 수 있다. 3개의 체외수정란을 vitrification 용액에 노출시키고 OPS 또는 GMP vessel에 loading 시킨 후 액체질소에 침적하는데까지 20~25초 이내에 실시하였다. 동결ㆍ융해한 배반포기배는 0.25와 15 M sucrose solution 및 TCM 1999에 각각 5분씩 차례로 희석한 후 10% FCS가 첨가된 TCM 199에 24시간동안 배양하였다. OPS(75.9%)와 GMP(80.0%) 방법간의 re-expanding 율은 유의적 (P＜0.05)인 차이가 없었다. OPS(34.1%)와 GMP(37.5%) 방법에서 hatching 율은 intact group(54.3%) 보다도 유의적 (P＜0.05)으로 낮았다. 비록 GMP straw 당 3개 이하의 blastocysts 를 loading 하였더라도 narrow portion(83.3%) 보다도 wide portion(S6.7%)에서 vitrified 되었다면 re-expanding 율이 유의적 (P＜0.05)으로 낮았다. 비록 30초 처리군과 무처리군 간에는 유의적인 차이가 없었지만 0.05% pronase 용액에 30, 60 및 90초간 처리군 (45.9, 54.7 및 57.5%)의 hatching 율은 무처리구 (35.0%) 보다 유의적 (P＜0.05)으로 높았다. 이러한 결과들은 OPS와 GMP vitrification vessel은 체외생산된 배반포기배의 높은 생존율을 얻을 수 있다. 그러나 GMP vessel은 L$N_2$침적 후 vessel의 floating을 방지하기 위한 또 다른 cap 이 필요하지 않다는 유리한 점을 가지고 있다. 수정란의 loading 위치, 즉 narrow 또는 wide portion에 따라 소 체외 생산된 배반포기배의 생존력에 제한적인 요인으로 고려된다. 0.5% pronase 용액에 60 또는 90초간의 노출은 융해후 hatching 율을 향상시킬 수 있었다.

• 한국수정란이식학회지
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• 제18권3호
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• pp.179-186
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• 2003

Human embryonic stem (hES) cell lines have been derived from human blastocysts and are expected to have far-reaching applications in regenerative medicine. The objective of this study is to improve freezing method with less cryo-injuries and best survival rates in hES cells by comparing various vitrification conditions. For the vitrifications, ES cells are exposed to the 4 different cryoprotectants, ethylene glycol (EG), 1,2-propanediol (PROH), EG with dime-thylsulfoxide (DMSO) and EG with PROH. We compared to types of vehicles, such as open pulled straw (OPS) or electron microscopic cooper grids (EM grids). Thawed hES cells were dipped into sequentially holding media with 0.2 M sucrose for 1 min, 0.1 M sucrose for 5 min and holding media for 5 min twice and plated onto a fresh feeder layer. Survival rates of vitrified hES cells were assessed by counting of undifferentiated colonies. It shows high survival rates of hES cells frozen with EG and DMSO (60.8％), or EG and PROH(65.8％) on EM grids better than those of OPS, compared to those frozen with EG alone (2.4％) or PROH alone (0％) alone. The hES cells vitrified with EM grid showed relatively constant colony forming efficiency and survival rates, compared to those of unverified hES cells. The vitrified hES cells retained the normal morphology, alkaline phosphates activity, and the expression of SSEA-3 and 4. Through RT-PCR analysis showed Oct-4 gene expression was down-regulated and embryonic germ layer markers were up-regulated in the vitrified hES cells during spontaneous differentiation. These results show that vitrification method by using EM grid supplemented with EG and PROH in hES cells may be most efficient at present to minimize cyto-toxicity and cellular damage derived by ice crystal formation and furthermore may be employed for clinical application.

• Journal of applied mathematics & informatics
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• 제17권1_2_3호
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• pp.797-802
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• 2005

We generate simplex polynomials by using a method, which produces an OPS in (d + 1) variables from an OPS in d variables and the Jacobi polynomials. Also we obtain a partial differential equation of the form $${\Sigma}_{i,j=1}^{d+1}\;A_ij{\frac{{\partial}^2u}{{\partial}x_i{\partial}x_j}}+{\Sigma}_{i=1}^{d+1}\;B_iu\;=\;{\lambda}u$$, which has simplex polynomials as solutions, where ${\lambda}$ is the eigenvalue parameter.

• 정보처리학회논문지D
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• 제13D권2호
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• pp.207-214
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• 2006

서열화가 완성된 유전체의 수가 최근에 빠르게 상승하고 있지만, 상동성에 의한 단백질 기능을 예측하는 방법은 충분히 연구되고 있지 않다. 서열화가 완성된 다수의 유전체로부터 유전체 상호간의 BLAST 최대 히트(best-hit)를 사용하여 OPCs(Orthologous Protein Clusters)를 만드는 일은 성공적으로 연구되어 왔다. 그러나 OPCs를 수작업으로 구축하는 것은 시간과 노력이 많이 드는 일이다. 이 논문에서 우리는 서열화가 완성된 다수의 유전체로부터 OPs(Orthologous Proteins)를 클러스터링하는 자동화 방법을 제시하고, 해당 클러스터링의 타당성을 수학적으로 증명 한다.