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        검색결과 1,648

        823.
        2007.09 구독 인증기관 무료, 개인회원 유료
        Cell behavior of the transformed cells is known to affect by interaction with extracellular matrix (ECM) proteins and integrin. To investigate the alterations of both integrin expression and cell-matrix interaction during neoplastic conversion of human oral kerationcytes, we studied expression levels of integrin subunits by flow cytometry and cellular responses to the ECM proteins in normal human oral keratinocytes (NHOKs), HPV-immortalized HOK-16B line, and three oral cancer cell lines established from HOK-16B line, CTHOK-16B-BaP, CTHOK-16B-DMBA, and CTHOK-16B-Dexa lines. The expression levels of α and β integrin subunits were shown decreased tendency in human oral keratinocytes undergoing immortalization and tumorigenic transformation except CTHOK-16B-DMBA line tested. Although αuβ6 integrin is known to be highly expressed in squamous cell carcinomas, and the altered integrin expression is suspected to be associated with cellular carcinogenesis, αu integrin subunit and αuβ6 egrin did not express in oral cancer cell lines tested. Cell behavior to the ECM proteins in HOK-16B line was generally similar to that of exponentially proliferating NHOKs. The adhesion activity profiles of type I collagen were very similar to that of its laminin counterparts, but fibronectin showed minimal adhesion activity under our conditions compared to the BSA control. The ability of the CTHOK-16B-BaP line to spread upon type I collagen and laminin markedly decreased, but migration was notably increased on type I collagen. In contrast, CTHOK-16B-DMBA and CTHOK-16B-Dexa lines spread less but migrated more upon type I collagen than immortalized HOK-16B line. These data indicate that downregulation of integrin subunits causes the changes of cellular responses to the ECM proteins during neoplastic conversion of human oral keratinocytes, and that cellular responses to the ECM proteins in oral cancer cell lines established by exposing different carcinogens are variable according to chemical carcinogens treatment.
        4,000원
        824.
        2007.09 구독 인증기관 무료, 개인회원 유료
        본 연구는 사람 H-transferase가 과발현하는 돼지 체세포주를 개발하는데 있다. 돼지 세포에 사람 H-transferase 유전자를 발현시키는 것은 이종간 장기 이식에 있어서 초급성 거부 반응을 방지하기 위한 한 가지 방법이다. 본 연구에서는 과발현 벡터를 구축하기 위하여 사람 H-transferase을 HepG2 세포로부터 동정하였으며, 이 유전자를 CMV promoter를 이용하여 발현할 수 있도록 포유동물 발현 벡터인 pRc/CMV 벡터에 삽입하였다. 또한, 돼지 산자의 귀 세포를 이용하여 체세포를 수립한 후 jetPEI DNA transfection reagent를 이용하여 벡터를 도입하였고, 300 μg/ml의 G418로 12일간 선별하였다. PCR을 이용하여 선별된 colony들을 분석한 결과, 벡터가 도입되었음을 확인하였고, RT-PCR을 이용하여 사람 H-transferase mRNA가 발현하는 것을 확인하였다. 본 연구에서 확립된 세포주는 사람 H-transferase가 과발현하는 형질 전환 돼지의 생산에 이용될 수 있을 것으로 생각된다.
        4,000원
        825.
        2007.09 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 hG-CSF의 발현을 유도적으로 조절하기 위한 FIV-Tet-On lentivirus vector system을 구축하고자 하였다. hG-CSF는 호중성구 계열 세포의 증식과 분화, 생존에 영향을 미치는 물질로서, 이 유전자의 발현을 증가시키기 위하여 FIV-Tet-On vector 상의 hG-CSF나 rtTA2SM2 서열의 3' 위치에 WPRE 서열을 도입하였다. 구축된 각각의 vector는 293FT 세포에 일시적으로 transfection하여 virus를 생산하였으며, 이 virus를 일차 배양 세포인 CEF와 PFF에 감염시켰다. 각 세포에 전이된 hG-CSF의 발현 양상을 관찰하기 위하여 doxycycline을 첨가하거나 첨가하지 않은 배지에서 배양한 후 quantitative real-time PCR, Western blot과 ELISA를 이용하여 hG-CSF 유전자의 발현 정도를 비교 측정한 결과, CEF에서는 WPRE가 hG-CSF의 3' 위치에 도입된 경우에 발현량과 유도율이 가장 높은 것으로 나타났고, PFF에서는 rtTA 서열의 3'위치에 도입된 경우에 발현량과 유도율이 가장 큰 것으로 확인되었다. 이 FIV-Tet-On vector system은 형질 전환 동물의 생산이나 유전자 치료에서 문제시되는 외래 유전자의 지속적인 과다 발현에 의한 개체의 생리적인 부작용을 최소화하기 위한 해결 방법으로 제시될 수 있을 것이다.
        4,000원
        826.
        2007.09 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 SV40 Tag을 마우스 albumin 유전자의 promoter/enhancer 조절 하에 발현하도록 설계된 재조합 유전자를 마우스 1세포기 수정란에 미세 주입하여 형질 전환 마우스를 제작하고 이들의 인체 간암 모델로써의 적합성을 조사하였다. 형질 전환이 확인된 총 11개체의 founder 생쥐들 중 4개체가 간암을 일으켰고, 두 개체는 신장암을, 한 개체는 피부 및 뇌에서 종양을 각각 일으켰다. 이들로부터 외래 유전자를 계대 유전하는 3가계를 얻었다(#1-2, #1-6, #1-11). 이들 가계의 자손들에서 8주령(#1-2, #1-6) 혹은 10주령(#1-11) 시부터 간암이 반복적으로 발생되었으며, #1-11 founder 개체에서 폐로 암세포가 전이된 것 외에는 다른 조직에서의 형태학적 변이가 발견되지 않았다. 간암 발생은 조직학적 변화에 따라 3단계로 나눌 수 있었다. 즉, 출생에서 3주령까지는 간세포의 과량증식을 보이나 세포핵의 이상은 관찰되지 않았으며, 4주령부터 7주령(#1-2, #1-6) 혹은 9주령(#1-11)까지는 diffuse liver cell dysplasia를 나타내지만 tumor nodule은 발견되지 않았고, 그 이후에는 liver dysplasia를 배경으로 간암이 발생하였다. 본 연구에서 작출한 간암 모델 마우스는 인체 간암과 일부 유사한 소견을 보였는 바 인체 간암 기전 연구를 위한 유용한 동물 모델로 이용할 수 있을 것으로 생각된다.
        4,000원
        827.
        2007.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to examine the effects of vi tamin D3 and 1'etinoic acid(RA) on the human mesenchymal stem ce!ls(MSC) g1'owth and osteogenic differentiations. Cell proliferation, mineralization, cell cycle, expression of cell cycle regu l atOJγ proteins and markers fo1' osteogenic differenatiaiton were determined by MTI assay, mineralization assay, flow cytomet1'Y‘ and Western blot analysis, respectively. Cell viability was dec1'ease by each vitamin D3 and RA added to MSC. it was more decrease by vitamin D3 and RA. Mineralized nodule formation revealed similar expression pattern with positive cont rol group at vitamin D3 and RA mixed add to MSC. At vitamin D3 and RA mixed add to MSC after 7 days of incubation was increase G1 s tage. after 21 days of incubation was inhibit cell cycle prog1'ess by inc1'ease of sub-G1 Treatment vitamin D3 to MSC inhibits p53 and p21, but inc1'ease pRb. RA inhibit p53, but increase p21 and pRb, vitamin D3 plus RA group was same as added RA group. so two vitamin was effect to inhibited cell growth each different mechanism. Expression of BMP-2 protein was prominent in osteogonic supplement treated g1'oup of MSC at 2 weeks cultivation days, but vi tamin D3 treatment decreased BMP-2 expression rather than in (+) control group. BSP protein was notably increased in the OS compa red to positive controls at 2 weeks cultivation, but similar to that of vitamin D3 group t1'eatment group and was least expressed in plus RA mixed group, at 3 weeks, BSP expression was similar to 1'esult of 2 weeks Collectively, these results shows that vitamin D3 and RA have diffe1'ential effects on the MSCs g1'owth and differ entia tion 211
        4,000원
        828.
        2007.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cytokines play a vital role in the host immune response by regulating the development and function of im munocompetent ce11s One immunomodulatory agent that has received attention in oncology research recently is interleukin - lO(IL-lO). IL-IO inhibi ted tumor antigen presenta tion and induced energy in T lymphocytes that had been s timu lated by autologous MHC class II positive tumor ce11s Patients with head and neck cancer have been shown to exhibit profound irnmunosuppression. The mechani sm by which tumor ce11s alter immunological function in the host is poorly understood. Recently. production of biological active IL- IO was confirmed in ovar‘ian cancer, melanoma, skin cancel‘ & head and neck cancer, suggesting that IL- lO reduces the function of tumor infiltrating lymphocytes and contributes to the tumor growth. IL-IO expression has not been examined extensively in human oral cancer and has not yet been cla rified. The purpose of t his study were to investigate IL-IO mRNA and protein expression in NHOK, IHOK and oral squamous ce11 carcinoma(OSCC) ce11 line by RT-PCR and irnmunoslot blotting, and to apply its results to examine its thera peutic significance for oraJ cancers. Cultured NHOK showed a lower level of IL-IO mRNA and protein expression than cultured IHOK and HN 22 OSCC cell line under pre and postconfluency. HN 22 OSCC cell line under pre and postconfl u ency. showed the highest level of IL-I0 Cul tured IHOK showing a intermediate expression of IL- IO could be as a vaJ u a bJe marker for oral carci nogenesis ste p. During the terminal differentiation of a11 the ce11 lines, IL- IO ex pression was significantly unchangeabl e. IL- IO mRNA expression of a11 the ce11 lines was consistent with IL-10 protein expression. It suggested that IL- lO expression might play an important role in oral carcinogenesis and IHOK could be a valuable marker for oral carcinogenesis step. And aJso IL- 10 related gene may be future targets for gene discovery and possi bJy therapeutic intervention
        4,000원
        830.
        2007.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        5,100원
        831.
        2007.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The human meta pneumovirus(hMPV) is a recently identified Paramyxovi rus associated with acute respiratory tract infect ions(ARIs) ranging from upper ARIs to severe bronchiolitis and pneumonia in humans. We studied the prevalence of this new virus in Seoul from 2005 to 2006 A total of 757 specimens were collected by nasopharyngeal swab from ARI patients and were tested fo1' the presence of hMPV by reverse transcription-PCR. Of these‘ 28 were detected the L gene of hMPV. The age range of the patients with hMPV infection was 1 months to 67 years with similar numbers of females (59 .3%) and males(40.7%) . The main symptoms were cough(100%) , fever (82 .1%) , nasal mucus(67.8%) ‘ vomit(25%) . diarrhoea( 21. 4%). and difficult breathing(21. 4%) and the main diagnosis we1'e pneumonia, bronchioli tis, nasoharyngiti ts, and rhmJtls Virus activity peaked in March and May. Phylogenetic analysis of the N gene confirmed the existence and si multaneous circulation within one epidemic season of hMPV isolates belonging to two genetic lineages.
        4,000원
        832.
        2007.06 구독 인증기관 무료, 개인회원 유료
        Oral squamous carcinoma (OSC) is the most common malignant neoplasm of the oral mucosa. Although the etiology of OSC is not fully understood, accumulated evidences indicate that the activation of proto-oncogenes and the inactivation of tumor suppressor genes underlie the disease development. An OSC cell line, YD-9 was newly established and characterized. However, the mutational analysis of p53 gene was not performed. Thus, in this study, the presence of mutation in the p53 gene was examined by amplification of exon-4 to -8 and subsequent DNA sequencing. Two point mutations were found in exon-4 and -6: A to G, resulting in amino acid change Tyr to Cys in exon-4, and C to G, resulting in amino acid change Gly to Arg in exon-6, respectively. Any mutation was not found in the exon-5, -7 and -8. The presented results would contribute to basic research to understand the biological mechanism of OSC using YD-9 cells.
        4,000원
        833.
        2007.06 구독 인증기관 무료, 개인회원 유료
        Periodontitis is a chronic infectious disease that leads to periodontal destruction, and is one of the major causes of tooth loss in humans. The osteoclast differentiation factor (ODF), which is also known as the receptor activator of the NF-kB ligand (RANKL), is a surface-associated ligand on bone marrow stromal cells and osteoblasts. RANKL activates its cognate receptor, RANK, on osteoclast progenitor cells, which leads to the differentiation of mononucleated precursor cells. Osteoprotegerin (OPG) is a decoy receptor that is released from stromal cells and osteoblasts to inhibit the interaction between RANKL and RANK. Although the precise mechanism of bone loss in periodontitis is unknown, the differentiation and activation of osteoclasts by OPG-ODF-RANK signaling might play the role in periodontal bone destruction. The relationship between the concentration of sex hormones and the expression of ODF and OPG was examined by treating human gingival fibroblasts and periodontal ligament cells with the normal serum concentration of estrogen or progesterone during menstruation or at menopause. The ODF/OPG relative ratio was elevated at the concentration observed during ovulation in human gingival fibroblasts and at the concentration observed between ovulation and menstruation in periodontal ligament cells treated with estrogen. However, the ratio was <1 at all concentrations in both cells treated with progesterone. In the case of menopause simulated by estrogen depletion, the ratio was <1 in human gingival fibroblasts but >1 in periodontal ligament cells.
        4,000원
        834.
        2007.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구의 목적은 수공간에 대한 감성을 대표하는 어휘를 선정과 수공간의 감성 유형을 분석하기 위해 수행되었다. 수공간의 감성평가를 위한 어휘를 선정하는 것은 감정의 잣대를 만드는 일이기 때문에 감성어휘를 정확하게 선정하는 것은 매우 중요한 일이다. 기초어휘 수집을 위해 첫 단계에서 수공간에 대한 감성을 표현하는 어휘를 수공간 연구, 경관 평가 연구, 환경디자인 감성연구 등에서 수집 후 최종 129개의 어휘를 선정하였다 두 번째 단계에서는 수집된 어휘를 일반인들에게 제시하여 수공간의 감성을 나타내는 어휘로서 적절함의 정도를 5점 척도로 표시하도록 하여, 평균 3.5점 이상의 39개 어휘를 선발하였다. 세 번째 단계로 이 설문으로부터 나온 데이터에 대해 요인분석, 군집분석, 다차원분석을 실시하여 수공간에 대한 9개의 감성어휘를 추출하였다. 수공간 감성평가에 최종적으로 선발된 어휘는 체험적, 감각적, 자연적, 조화된, 깨끗한, 기분좋은, 역동적, 개방적, 낭만적이다.
        4,300원
        835.
        2007.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The process 0 1' wound healing needs the deposition of collagen and non-collagenous compounds, followed by the remodelling of extracellul ar matrix Recently, it has known that LEDs irradiation can help wound healing to accelerate the cell proliferation. But its mec hanism is not elucidated yot. The purpose of the present study is to observe the expression level of extracellular matrix by 635nm LEDs ir radiation. Human gingival fibroblasts were primary cultured, treated arac hidonic acid (때 and followed by LEDs irradiation. To observe the mRNA expression of extracellular matrix, cDNA mlcroarray was ca n‘ ied out 1n present study, 3 experimental groups were categorized into control, AA-treated group, and AA-treated with LEDs irradiation group. The differential expressions of MMP-1, -2, -3, - 10, - 11, -14, -16, - 17, -25 and TIMP-1, -2, -3. -4 were observed. Especially, mRNA expression of T1MP-3 was 10 fold decreased in arach idonic acid -treated with 635nm LEDs irradiation group. Finally, LEDs irradation can affect the expression level of MMPs and TIMPs, which lead to prolifer ation of gingival fibroblasts and result in would healing
        4,000원
        836.
        2007.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We have examined the effect of NO donor, S-nitl‘ oso-N-acetyl-DL-penicillamine(SNAP) on heme oxygenase-1 (HQ-l) ex pression in human oral immortalized & malignant keratinocytes, and investigated in the control of keratinocyte proliferation evidence tha t HO-1 cou ld be involved in a low dose of NO, NO inhibitor, HOinducer, and HO inhibitor medi ated cytoprotect ion against cytotoxi city induced by a high dose of NO Oral keratinocyte growth inhibitory or anti-proliferative effects were exerted by with SNAP and hemin in a dose- and cul tivation time dependent manner The level of HQ-1 protein was increased in all cell types after exposure hernin dose, and the hemin induced HQ-1 protein achieved at higher maximum level by 12 hrs in all kind of cells , The pretreatment of cells with 0, 2 μ M SNAP reduced 1 mM SNAP-induced death in IHOK and HN4 cells , These cytoprotective effects on high dose of NO induced HQ-1 expresion and cell ular toxicity were blocked by low dose of SNAP, HCB, and ZnPP IX supporting the involvement of HQ-1 in high dose NO induced growth arrest or cell death, But these cytoprotection pattern is different from immortalized and malignant keratinocytes , These results indirectly demonstrate that HQ-1 could be involved in cytoprotection by NO priming against high dose NO induced cytotoxicity in immortalized and maigla nt oral keratinocytes, Thus, HQ-1 might be an important cellular target of NO donor, with clinical implications for the pre vention of inJlammatory di seases and anti-tumor immunity
        4,000원
        837.
        2007.06 구독 인증기관 무료, 개인회원 유료
        본 논문에서는 MPEG-7 시각 기술자를 조합하고, 유사도 수행에서 초기 중요도 가중치를 고려한 관심영역(ROI: Region-Of-Interest) 기반의 의료 영상 검색 기법을 제안한다. 의료 영상에서 의미 없는 배경 부분을 제거하고, 영역 추출의 처리 시간을 줄이는 관심 윈도우(AW: Attention Window)를 생성하여 관심 영역 분할을 수행한다. 또한 인간 시각에 부합하도록 검색 성능을 향상시키기 위하여 유사도를 비교하는 영역에 대한 초기 가중치를 설정하여 특징 벡터 거리를 계산하였다. 실험에서 제안된 기법은 의료 영상을 효과적으로 찾아내며, 조합된 특징과 가중치를 이용한 유사도 측정으로 검색 성능이 향상됨을 보여준다.
        4,200원