This study was conducted to evaluate the effect of cytochalasin B (CB) treatment in the activation medium on the development of somatic cell nuclear transfer (SCNT) rat embryos. Fetal fibroblast cells were isolated from a Day 14.5 fetus, and the oocytes for recipient cytoplasm were recovered from 4-week old Sprague Dawley rats. After enucleation and nuclear injection, the reconstructed oocytes were immediately exposed to activation medium consisting of 10 mM SrCl2 with or without CB for 4 hr, and formation of pseudo-pronucleus (PPN) was checked at 18 hr after activation. Then, they were transferred into day 1 pseudopregnant recipients (Hooded Wistar) or cultured for 5 days to check their developmental competence in vivo or in vitro. The number of PPN was not affected by CB treatment during the activation. However, CB treatment supported pre-implantation development of rat SCNT embryos. Embryos generated by the procedures of SCNT were also capable of implanting, with 1 implantation scar found from a recipient following the transfer of 87 SCNT embryos to four foster mothers. The result of the present study shows that rat SCNT embryo can develop to post-implantation stage following treatment with CB.

This study was conducted to investigate the effects of oocyte maturational age and activation condition on in vitro development of porcine parthenogenetic embryos (parthenotes). Porcine follicular oocytes were matured in vitro for 30 to 44 hr. Maturation rate was examined during in vitro maturation (IVM) every 2 hr interval. The cdc2 kinase activity was measured at 36 and 44 hr of IVM. Some oocytes were activated at 36 or 44 hr of IVM by three different conditions; 1) single electric stimulation (1.5 kV/cm for 30 sec; ES), 2) double electric stimulations (1.5 kV/cm for 30 sec, followed by 1.0 kV/cm for 50 sec after 1 hr; ES+ES) or 3) ES+ES followed by culture in 6-dimethlyaminopurine (6-DMAP) for 4 hr (ES+ES+D), and cultured for 6～7 days. Maturation rate was significantly increased as culture period was increased to 36 hr (66.9%, p<0.05), and then gradually increased to 87.1% at 44 hr of IVM. The cdc2 kinase activity was decreased (p<0.05) with culture period prolonged from 36 hr to 44 hr. Lower blastocyst formation rate (4.3%, p<0.05) were obtained by ES in 36 hr-matured oocytes compared to other treatments (16.5 and 20.5%) in the same age and the same treatment in 44 hr-matured oocytes (15.0%). High blastocyst formation rate (23.6%) was obtained by ES+ES+D in 44 hr-matured oocytes (p<0.05). These results demonstrate that porcine oocyte activation and in vitro development of parthenotes can be affected by interactions between oocyte maturational age and activation condition.

Cordyceps militaris is well known as a traditional herbal ingredient, which has been used for patients suffering from cancer in oriental medicine. In this study we have investigated the biochemical mechanisms of anti-proliferative effects by C. militaris extract(CBE) in human breast cancer MDA-MB-231 cells. It was found that CBE treatment induced chromatin condensation, mitochondrial energization, annexin V staining and sub-G1 phase DNA content. These indicators of apoptosis correlate with the mitochondrial dependent pathway, which results in the activation of caspase-3 activity. Both the cytotoxic effect by CBE treatment were significantly inhibited by z-DEVD-fmk, a caspase-3 inhibitor, demonstrating the important role of caspase-3 in the observed cytotoxic effect. Co-treatment of CBE and LY294002, resulted in significantly induction of apoptosis. These results indicate that caspase-3 is a key regulator of apoptosis in response to CBE in human breast cancer MDA-MB-231 through down regulation of Akt, and that the C. militaris extract may therefore have therapeutic potential against human breast cancer.

본 연구는 효율적인 돼지 난자의 활성화를 통한 수핵란의 대량 확보를 위하여 ethanol, Ca-ionophore 및 strontium의 최적 농도 및 노출 시간을 규명하기 위하여 실시되었다. Ethanol은 10%에서 10분간 노출시켰을 때 난할율과 배발달 성적이 각각 51.4%와 45%로 다른 처리구에 비하여 유의적으로 높았으며 (P<0.05), Ca-ionophore는 에서 2분간 노출시켰을 때 난할율과 배발달 성적이 유의적으로 높았다. 또한 st

In mold structure machining, tool interference is a phenomenon which results from a collision between a blade of tool and a workpiece. Also tool collision is a phenomenon which results from a collision of holder with the object to be machined. These phenomena not only cause damages to mold and tool but also increase machining time and cost. To detect a collision of a tool to mold structure, first of all, the mold structure and a tool must be defined with famous geometric models such CSG, B-rep, and Voxel. A tool is defined as a combination of the blade, the shank, and the holder. This thesis reviews various collision detection algorithms using z-map and computer 3D graphic collision detection algorithms for the tool in machining a mold structure.

Since 1990's, many enterprises have constructed Integration Information System. Especially, they want to become an advanced company use ERP package. Already, ERP system come to high level which is stabilized and support independent business process of many industry sectors. Therefore, important success factors for ERP project are change management and organization activation. Although most companies had previous good plans, but those are not satisfied. Because of failed to change management and discontinued next activity for promotion. This paper studied success factors of project team and plan for organization activation. Also, it proposed next study subject about investigate the role of the member of task force team as a factor that makes the ERP system a success. The results of this study can be used for a successful construction of the ERP system as a solution about Internal problems of Project team.

목적 : 인간의 뇌는 손상을 받은 후에 자발적인 회복이나 뇌신경 회로의 재조직화를 통해 기존의 기능을 회복 할 수 있다．이러한 뇌의 재조직화가 뇌졸중 환자의 운동 기능회복에 중요한 역할을 하는 것으로 알려져 있다．최근의 뇌지도화 기법이 발달함에 따라，뇌손상 환자의 운동 기능 회복에 따른 뇌신경망의 재조직화에 대한 몇 가지 기전이 보고되었고，특히 뇌손상 부위에 따라 뇌활성화되는 양상이 서로 다르게 나타날 수 있다고 추정되고 있다．따라서 본 연구는 뇌손상 부위에 따른 뇌 활성도의 양상을 비교하고자 하였다． 연구방법 : 본 연구에 참여한 대상자는 손의 운동 기능이 일상생활을 독립적으로 할 수 있는 정도로 회복되고 그 기능이 서로 비슷한 대뇌피질(n＝2) 또는 방사관(n=2)에 국소적인 손상을 받은 뇌경색 환자 4명과 신경학적 증상에 대한 과거 병력이 없는 정상 성인(n=7)을 대상으로 하였다．환자군에서 도수근력검사，악력，퍼듀-페그 보드와 경상운동의 정도를 측정하였고，모든 대상자는 손가락의 굴곡과 신전을 반복하는 과제를 실시하는 동안，기능적 자기공명영상의 촬영에 참가하였고，이 때 활성화되는 뇌부위를 분석 비교하였다． 결과 : 환자군에서 평가된 손의 운동 기능은 모두 비슷하였지만，뇌 활성화되는 양상은 서로 다르게 나타났다，대 뇌피질에 손상을 받은 환자들은 정상인 및 그들의 비손상측 손 운동시 활성화되는 양상과 같이 운동을 수행한 손의 반대측 일차운동피질에서 활성화를 보였다．방사관에 손상을 받은 환자군은 양측의 일차운동피질에서 활성화를 보였다． 결론 : 뇌손상 부위는 대뇌피질과 방사관으로 분류되었고，손의 운동 기능 회복의 정도는 비슷하였다．하지만 활성화된 부위는 명확하게 다르게 나타났다．따라서 뇌손상 부위에 따라 뇌신경 회로의 재조직되는 형태가 서로 다르게 나타난다는 것을 알 수 있다．이는 뇌신경재활의 영역에서 마비된 손의 기능이 회복됨에 따라 뇌신경망 에서 나타나는 가소성을 증명하는 것으로，환자의 예후 측정과 신경생리학적 기전에 대한 이해를 제공할 것으로 생각된다．

본 연구는 융합 전 수핵란의 활성화 처리 유무와 활성화 처리 시간이 소 체세포 유래 핵이식란의 체외 발육능에 미치는 영향을 검토하기 위해 수행하였다. 소 체외성숙란의 탈핵 후 체세포 핵을 이식하고 일부는 전기 융합 후 활성화를 유기하였고(pre-AC), 일부는 먼저 활성화 처리 후 융합을 실시(post-AC)하였다. 난자의 활성화는 Ca2+-ionophore(A23187)로 처리 후 DMAP로 4시간 배양하는 방법으로 유기하였다. 핵이식란은 CR1aa액에서 9일간 배양하여 발육율을 검토하였으며, 활성화 후 30분～2.5시간에 고정하여 confocal microscope 하에서 핵형 변화를 검사하였다. 배반포기까지 발육율은 post-AC구(20.6%)가 pre-AC(15.3%)보다 다소 높게 나타났다. 또한 활성화 처리를 하여 핵이식란의 배 발달을 비교한 결과 post-AC구가 더 늦은 배 발달 속도를 나타내었다. Post-AC구를 활성화 후 30분, 2시간, 4시간으로 나누어 융합하여 발육율을 검토한 결과 발육율에 차이가 없었다. 본 연구의 결과는 수핵란의 활성화 시간에 따라 핵이식란의 발육 및 핵형이 영향을 받을 수 있음을 시사한다.

  The most of national industrial complex were developed and supplied not according to the requirements of enterprise but the needs of the government. And it leads to current serious out of balance in demand and supply of industrial complex. Buckpyoung in