중성자가 조사된 흑연에 내재되어 있는 Wigner 에너지를 배출시키는 방법의 하나인 가열냉각공정의 적용 예로 DSC(미분 주사선 열량계) 측정을 통해 흑연으로부터 Wigner 에너지가 배출되는 열 배출 특성을 연구하였다. 일정온도 상승 방법 에 의한 DSC 운전에서 중성자가 조사된 흑연을 가열냉각(annealing)하는 동안 배출되는 Wigner 에너지의 총량과 처리온도에 따른 배출속도를 측정하였다. 연구로 2호기(KRR-2) thermal column 내에 위치별로 중성자의 조사량에 차이가 나는 흑연 시료를 분말로 만들어 상온에서 까지의 온도 범위에서 DSC를 운전하고 이로부터 Wigner 에너지의 배출 속도를 측정하였다. 가열냉각 동안 중성자가 조사된 흑연에서 배출되는 Wigner 에너지의 배출 특성은 가변적 활성화 에너지 속도 식으로 잘 상관시킬 수 있었다.

사용후핵연료 건식저장용기는 낙하사고조건에서 캐니스터의 건전성이 입증되어야 한다. 낙하사고조건은 캐니스터를 건식저장용기에 장입하기 위하여 저장용기의 상부에서 크레인으로 취급하는 도중에 캐니스터가 저장용기 내부의 받침대로 자유 낙하하는 조건이다. 저장용기 내부의 받침대는 이러한 조건에서 캐니스터의 구조적 건전성을 유지하도록 완충효과가 좋아야 한다. 본 연구에서는 다양한 저장용기 내부 받침대 에 대한 3차원 유한요소해석을 통하여 낙하사고조건에서 캐니스터의 구조적 건전성을 향상시킬 수 있는 구조를 결정하였다. 저장용기 내부 받침대는 탄소강으로 만들어진 원통 쉘의 내부에 콘크리트를 장입한 구조와 받침대 높이의 변화 없이 콘크리트 높이의 1/4정도에 탄소강과 폴리우레탄폼을 이용한 구조물을 사용하여 완충효과를 보완하고자 수정된 구조를 고려하였다. 완충체의 형상 및 구조를 결정하기 위하여 십자형상이나 원형의 탄소강 구조물을 받침대 상부에 위치하여 그 영향을 알아보았다. 이때 탄소강 구조물의 두께를 24 mm, 12 mm, 6mm로 변화를 주었다. 또한, 탄소강 구조물 사이에 충진하는 폴리우레탄폼의 밀도에 대한 영향을 알아보았다.

This study was conducted to examine the effect of IRES controlled reporter gene on screening and production of recombinant human erythropoietin (EPO) proteins from cultured CHO cells. The cDNA was cloned for EPO from human liver cDNA. Using site-directed mutagenesis, we generated recombinant human EPO (rhEPO) with two additional N-glycosylations (Novel erythropoiesis-stimulating protein: NESP). Wild type hEPO and NESP were cloned into expression vectors with GFP reporter gene under regulatory control of CMV promoter and IRES so that the vectors could express both rhEPO and GFP. The expression vectors were transfected to cultured CHO-K1 cells. Under microscopy, expression of GFP was visible. Using supernatant of the culture, ELISA assay, immunocytochemistry and in vitro assay using EPO dependant cell line were performed to estimate biological activity to compare the production characteristics (secretion levels, etc.) between rhEPO and NESP. The activity of NESP protein, obtained by mutagenesis, was described and compared with its rhEPO counterpart produced under same conditions. Although NESP had less secretion level in CHO cell line, the biological activity of NESP was greater than that of rhEPO. These results are consistent with previous researches. We also demonstrated that rhEPO and GFP proteins expressed simultaneously from transfected CHO cell line. Therefore we conclude that use of GFP reporter gene under IRES control could be used to screen and produce rhEPO in cultured CHO cells.

Adenocarcinoma NOS of salivary glands is characterized by a high rate of local recurrences and metastasis. Long-term survival rate of Adenocarcinoma NOS lis not promising. Thus, different chemotherapeutical approaches had been proposed for this neoplasm, including apoptosis induction by drugs. The current treatment of choice of adenocarcinoma NOS is controversible, and an effective treatment for them is not yet available. Chemotherpeutic agents that can be inhibit or reverse the tumor growth by targeting apoptotic pathways will be new candidates for cancer prevention and therapy. The purpose of this study were to study the effect of Brefeldin A(BFA) as apoptotic inducing agent in SGT cell line from human submandibular adenocarcinoma NOS and apply these results to make a plan of treatment and prognosis of salivary gland tumors involving adenocarcinoma NOS. SGT cells were treated with a 300μM BFA solution in serum-free medium during 18 hours. SGT cells were grown in DMEM with 10% fetal bovine serum served as controls. The growth curve and MTT assay for succinyl dehydrogenase activity were performed. For apoptotic analysis, fragmentation of genomic DNA was confirmed with gel electrophoresis. Transmission electron microscopy was assessed for the effect of BFA on SGT cells phenotype. Apoptotic cell recognition and counting were carried out with Annexin-V, caspase 3 and APo2.7 antibody through flow cytometry. Growth of SGT cell line was abrutply decreased after 1 day of BFA treatment. MTT assay for succinyl dehydrogenase activity of the cells showed about 55% after 300μM BFA treatment. Destruction of cellular organells, numerous vacuolation in the cytoplasm & nucleus, chromatin margination, & fragments of nucleus were seen with TEM after 300μM BFA treatment. DNA fragmentation of SGT cell line was induced by 300μM BFA treatment and confirmed by gel electrophoresis from genomic DNA extraction. Late apoptosis of the cells through flow cytometric analysis of Annexin-V staining as induced by 300μM BFA treatment. Early apoptosis of the cells through flow cytometric analysis of caspase 3 and Apo 2.7 staining was induced by 300μM BFA treatment. It suggested that early and late apoptosis of SGT cell line would be induced by Brefeldin A treatment in vitro study. This work evaluated the efficacy of BFA, a potent apoptosis inducer, on SGT cultured cell line. And BFA as chemotherapeutic agent will be used as the treatment choice for adenocarcinoam NOS, and be need to apply BFA to in vivo study & clinical approach in future.

Oral squamous cell carcinoma is the 1st most common malignancy in oral and maxillofacial area. HPV 16 has been strongly linked to progression of cervical carcinoma. E6 and E7 as a small DNA virus encoding two major oncoproteins of HPV 16 can act together to produce efficient immortalization of primary human epithelial cells. Thus it is important to pursue the development of Immortalized human oral keratinocyte(IHOK) culture model which could be related to the pathogenesis of oral squamous cell carcinoma. If we establish IHOK transfected by E6/E7 genes, IHOK will be accepted as a model system for HPV-linked oral carcinogenesis. The purpose of this study were to culture primary normal human oral keratinocyte(NHOK), and to establish IHOK for studying oral carcinogenesis in the future. NHOK was primarily cultured under normal culture condition, and transformed into IHOK by transfection of E6/E7 genes. After 100 passages depend on Ca++ condition, cultured IHOK was confirmed by growth curve, cornified cell envelope measurement, TGase 1activity, mRNA detection, tumorogenecity and anchorage independence assay. After 100 passages, cultured IHOK showed most basal cell and monolayer of polyhedral cells under 0.15mM Ca++, and small area of stratification and flattened epithelial cells with irregular border under 1.2mM Ca++. The cultured IHOK showed relatively resistant growth under high calcium condition. The E6/E7 mRNA was detected in cultured IHOK by RT-PCR. During the terminal differentiation in cultured IHOK, increased insoluble cornified cell envelope formation was accompanied with induction of TGase 1 activity. But the cultured IHOK showed less CEM and TGase 1 activity than those of cultured NHOK. Cultured IHOK showed non-tumorogenecity, but slight anchorage independence. We had developed a technique to transform NHOK into IHOK by transfection of E6/E7 genes. Cultured IHOK was established as intermediate stage cell to study the pathogenesis of human oral squamous cell carcinoma.

rt is well known that glycosaminoglycans are 01' fllndamental importance to the processes 01' morphogenesis and cytodifferentiati on dllring the teeth development , With HlD-TCH-SP(High - iron diamine-thiocarbohydrazide-silvel protcinntc) , s lllfatcd glycosaminoglycans such as chondroitin sulfate and heparan slllfate have been localized a t the III trastrllctural level i n a wide variety of tlssues The pmpose of this stlldy were to examine slllfated glycosaminoglycan at llltrastrllctllral level fo 1' the phase of morphogenesis and cytodifferentiation of hllma n fetal tooth germs, and to detect the protein expression of slllfated glycosaminoglycan by immunoslot blot Human tooth gerll1s fl'Oll1 the a lveolar bone of twenty still born fetuses we1'e fixed in a mixtllre of 2% gllltaraldehyde/1% forma ldehyde, The 미 t 1'athin sections were stained witb HID-TCH-SP and were treated with 0, 05% solution of t esticular hyaluronidase to identify the histochemical properties 01' tbe HID-TCH-SP stain deposits , For semi quantitative protein assay , immllnoslot blot was done Sulfated glycocongugated deposits were localized in DEJ, peri tubular dentin , and mantle dentin matrix‘ enamel prism sheath , interrod area , and enamel matnx Heparan sll l띠 te deposits i n DEJ resisted to testicular hyalllronidase treatment prior to HID-TCH-SP staining, Immunoslot blot s howed that• chondroitin sulfate was detected higher in enamel and dentin extract, while heparan sulfate was relatively expressed in enamel and dentin extract, but rarely expressed in enamel or dentin extract It suggest ecl that chonclroi tin and hepa ran slllfate woulcl play an important role in the formation of DEJ, while chondroitin sulfate would in the clevelopll1ent of enamel prism sheath, enamel matrix, and mantle 01' peritublllar clentin of human fetal tooth germs,

We analyzed the high resolution H,6 line spectra of CH Cygni obtained at the Bohyunsan Astronomical Observatory (BOAO) on April 2004. The temporal changes in the Hβ line profiles are reported. We obtained the equivalent widths of the Gaussian components. Using this we estimated the length of the gaseous nebula which emits the Hβ line and the mass loss rate from the star.

MCMB (mesocarbon microbeads) has been synthesized from coal tar pitch, petroleum pitch and polymer compound generally. But yield of MCMB was low about 20~40 wt% and was not above 50 wt%. Neither MCMB was replaced with natural graphite because of economic performance, refining MCMB, and control of the particle size distribution. This study was performed to elevate yield of MCMB and to develop technique of particle size distribution. As the result, yield of MCMB that was synthesized from coal tar pitch increased more than 60 wt% about raw material and particle size of MCMB was restrained according to control of QI (quinoline insoluble) ingredient in raw pitch, heat treatment temperature and time.