검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 1,690

        901.
        2006.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Pro-inflammatory cytokines are important mediators of cutaneous cellular activities during many oral mucosal diseases. IHOK culture model transfected by E6/E7 genes provide further evidence for the role of HPV in tumorogenesis. It is interesting to investigate cytokine expression of immortalized human oral keratinocyte(IHOK). The purpose of this study were to analysis cytokine mRNA expression levels of NHOK and IHOK by RT-PCR. IHOK showed about 5 fold increases of IL-6 compared with NHOK, while TNF-α was the lowest. It suggested that immortalization of NHOK with E6/E7 could result in elevated expression of IL-6, and IHOK be in the intermediate stage of oral carcinogenesis.
        4,000원
        902.
        2006.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 논문에서는 세계적으로 널리 사용되어지고 있는 초고층 건축물의 진동사용성 평가기준이 검토되었다. 초고층 건축물의 진동에 대한 사용성 평가기준은 바람에 의한 초고층 건축물의 가속도 응답의 크기로 나타내는 것이 일반적이다. 건축물의 가속도의 응답의 크기를 산정함에 있어서 두 가지의 서로 다 른 척도, 즉 최대가속도 또는 RMS가속도를 각 기준에서 채택하고 있는데 이에 대한 상이점을 토의하고 각 국의 진동사용성 평가기준을 고찰함으로써 우리나라에는 어떤 진동사용성 평가기준이 적합한가에 대한 논의를 시작하고자 하였다. 그리고 건축물의 각기 다른 응답을 조사하여 최대가속도와 RMS가속도와 관계를 면밀히 검토하고 각각에 대해 기술적인 논거를 기술하였다.
        4,000원
        910.
        2006.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Since ancient Eygypt, various dental materials were used for lost teeth including gold. The key point of this materials were nontoxic to human body. Since early of 1990's, dental implant was done for recovery of maxillofacial defects. From middle of 1970's, osseointergation concept of implant was introduced and performed in dental field. Biocompatibility of titanium showed good effect for osseointergration but had some problems (Galvance current and toxic corrosion) with suprastructures such as gold crowns. This study was performed to make safe dental implants which have reduced Galvanic currents and corrosion. 3 kind of dental casting gold alloys (different Gold contents, 1㎝×1㎝×0.1㎝ plates.) were used as experimental group, while Titanium were used as control group. Normal human osteoblasts(NHOsts)were cultured during 1-4weeks for histologic study. For analysing the calcium(Ca), Phosphorus(P) and alkaline phosphatase(ALP), NHosts were cultred during 2-23days. After experiments, histologic finding were observed by LSM and SEM. Ca, P, ALP concentration by automatic biochemical analyzer were analyzed by ANOVA test and linear regression method. The results were as follows. Biocompatibility of dental casting gold alloys were similar to titianium alloys histolgically. Biochemical analysis of dental casting gold alloys had no significant difference to titianium alloy except AIGIS-Fine. We could conclude that biocompatibility of dental casting gold alloys with high contents of gold were superior to that of low contents and alloys with high contents of gold had no significant difference from titanium on NHost culture. Gold dental implant might be better than titanium implant due to similar biocompatibility and no galvanic currency.
        4,500원
        911.
        2006.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        It has been reported that light-emitting diodes(LED) can be used in the treatment of oral diseases. Although bio-stimulatory effects of LED irradiation such as promotes stimulation of wound healing have been well known, there are few reports about molecular mechanism associated with cell cycle by LED irradiation. The purpose of present study was to examine the molecular event in cell cycle of LED irradiation on primary human gingival fibroblast(hGF) in vitro. The source of light for irradiation was a continuous-wave LED emitting at a wavelength of 635nm, and manufactured that energy density was 5mW/cm2 on sample surface. The hGF were irradiated for 1 hour at 37℃ in 5% CO2 humidified chamber. Experimental samples were acquired at 0 (right after irradiation), 8 and 24 hour after irradiation. To investigate the molecular mechanisms associated with cell cycle, growth phase was determined by flow cytometry and mRNA expression of cyclin A, cyclin B, cyclin D1, cyclin E, cdc2, PCNA, p18, p27, p21, and p53 were determined by real time RT-PCR. Flow cytometric analysis demonstrated the percentage of cells in the G1 and S phase were decreased, but the G2 phase increased, which showed cells irradiated by LED were transitioned from S to G2 phase. For mRNA expression, cyclin B, cdc2, PCNA and p53 were increased at 0 hour after irradiation, and most of cell cycle molecules were increased at 8 hour after irradiation. At 24 hour after irradiation, cyclin A, cyclin E, PCNA and p18 were increased. Taken together, LED irradiation induced proliferation of hGF cells through transition from S to G2 phase.
        4,000원
        912.
        2006.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Basis frame-work's base in a semiconductor industry have gas, chemical, electricity and various facilities in bring to it. That it is a foundation by fire, power failure, blast, spill of toxicant huge by large size accident human and physical loss and damage because it can bring this efficient, connect with each kind mechanical, physical thing to prevent usefully need that control finding achievement factor of human factor of human action. Large size accident in a semiconductor industry to machine and human and it is involved that present, in system by safety interlock defect of machine is conclusion for error of behaviour. What is not construing in this study, do safety in a semiconductor industry to do improvement. Control human error analyzes in human control with and considers mechanical element and several elements. Also, apply achievement factor using O'conner Model by control method of human error. In analyze by failure mode effect using actuality example.
        4,000원
        913.
        2006.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        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.
        4,200원
        914.
        2006.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Amino acid transporters are essential for the growth and proliferation in all living cells. Among the amino acid transporters, the system L amino acid transporters are the major nutrient transport system responsible for the Na+-independent transport of neutral amino acids including several essential amino acids. The L-type amino acid transporter 1 (LAT1) is over-expressed to support cell growth in malignant tumors. The double stranded RNA-mediated RNA interference (RNAi) analysis can be in a wide variety of eukaryotes to induce the sequence-specific inhibition of gene expression. In this study, we examined the effect of LAT1 short interfering RNA (siRNA) on cell growth using siRNA of LAT1 in the KB human oral squamous cell carcinoma. In the RT-PCR analysis and western blot analysis, the siRNA of LAT1 inhibited expressions of LAT1 mRNA and protein. The uptake of [14C]L-leucine was inhibited by siRNA of LAT1. In the MTT assay, the siRNA of LAT1 inhibited the growth of the KB cells in the time-dependent manner, indicating that the growth inhibition of KB cell by the siRNA of LAT1 is induced by the blocking of neutral amino acid transport mediated by LAT1. These results suggest that the transport of neutral amino acids including several essential amino acids into the KB human oral squamous cell carcinoma is mediated mainly by LAT1. Further, the LAT1 would be a new target for the inhibition of cancer cell growth.
        4,000원
        915.
        2005.12 구독 인증기관 무료, 개인회원 유료
        Resveratrol (3,4',5-trihydroxy-trans-stilbene), a naturally occuring polyphenol compound which present in the skin of grapes and red wine has been considered to posses chemopreventive and antioxidant properties. However, little is known about the cellular actions by which resveratrol mediates its therapeutic effects. In this study, the effect of resveratrol on cell proliferation and induction of apoptosis in human osteogenic sarcoma (HOS) cells was investigated. IC50 value was determined to be approximately 60μg/mℓ. Chromosomal DNA framgmentation analysis showed the appearance degraded DNA in time-and dose-dependent manner upon treatment of resveratrol. In order to observe the molecular mechanism involved in resveratrol-induced apoptosis, Western blot analysis was performed. We observed the decrease in the level of procaspase-3, the zymogen form of active caspase-3 in resveratrol-treated cells. This result implies that caspase-3 is activated upon treatment of resveratrol. The activation of caspase-3 was confirmed by the cleavage of poly(ADP-ribose) polymerase. Taken together, our data demonstrate that resveratrol has anti-proliferative effect on HOS cells and induced apoptosis through activation of caspase-3 and PARP cleavage.
        4,000원
        916.
        2005.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cultured normal human oral kera tinocyte(NHOK) & inunortalized human oral keratinocyte(IHOK) provide a valuable model in ce llular proliferation and differentiation after proper stimulation , And it is interesting to study these estab lished cell lines esca ping normal control on their growth and differentiation, SPRR1 is induced during t erminal differ entiation 0 1' human epiderma l kerat inocytes but is rarely in anaplastic cells of keratinocyte origin, But SPR1 expression has not yet been explained during differ entiation uf NHOK and Lransformed oral keraLinocyLes , The purpose of this study were to examine mHNA and protein expression of SPR1 in response to a known differentiation signal, calcium conc in NHOK, lHOK a nd oral SCC ce ll line(HN 4) , and to apply these results for investigating the molecular mecha nisms of tra nsformed cellular differentiation , Primary cultured NHOK, established IHOK and HN 4 cell line were cul tured in KBM bullet kit Preconfluency of NHOK as control group was used Under O, 15mM Ca++ conc(Precon, Postcon) , and 1, 2mM Ca++ conc(Pos tcon)‘ the insoluble final pellets were measured fo1' cornified cell envelope measurements, and RT- PCR for SPRR1 mRNA meas urement, and immunoblotting for SPRR1 protein measurements in tripli cate , resp ectively , The terminal different ia tion of cu ltured NHOK and IHOK was depend on calcium concentration, while HN4 cell line was not SPRR1 mRNA and protein expression of cultured NHOK showed the highest among cultured IHOK & HN 4 cell line in hi gher ca lcium condition , SPRR1 mRNA and protein expression of cultured IHOK showed higher‘ than tha t of HN 4 cell line in hjgher cacium condi tion , SPRH1 was expressed in differentiation of NHOK and IHOK t ransfected by E6/E7 genes but ra rely expressed in malignant oral keratinocytes , It suggested that SPRR1 ex pression as kera tinocyte terminal diff‘erent ia tion marker involved in cellular cornification would be differentially effected by immorta li zation and ca rcinogenic transforma tion
        4,000원
        917.
        2005.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 topoisomerase inhibitors가 배양 각막 상피세포에서 세포고사를 유도하 는지를 조사기 위해 시행하였다. Topoisomerase inhibitors'{l camptothecin과 etoposide 를 제조사의 추천농도로 1-2 일 동안 배양하여 MTT assay를 이용하여 세포독성을 검 정하여 농도틀 정하고 세포고사를 확인하였다 세포고사의 형태적인 특징은 Hoechst 33342 staining, Annexin V - FITC/PI staining, DePsipher assay and CytoDEA TH staining을 이용하여 확인하였고 DNA fragmentation은 TUNEL파 agarose gel 전기 영동으로 확인하였다. Camptothecin 과 etoposide는 농도 의존성으로 세포고사룹 유또 하였는데 각막상피세포에서는 저l 조사의 추천농도보다 낮은 농도에서 세포고사플 유 도하여 다른 세포보다 민감한 것으로 나타났다- 이러한 결파로 볼 때 topOlsomerase l띠1ibitor는 각막상피세포에서 홀륭한 양성 대조군으로 활용될 수 있을 것으로 사료된다.
        4,000원
        918.
        2005.12 구독 인증기관 무료, 개인회원 유료
        The present study was conducted to investigate gelatinolytic activities in HAM and to determine whether there are any changes in gelatinolytic activity profiles when the cells are cultured in hepatogenic medium. Placenta was obtained during caesarean section of the volunteers, with informed consent. HAM were isolated from amniotic membrane using collagenase type A HAM were cultured in hepatogenic medium for 3 weeks and the conditioned media were obtained at day 7, 14 and 21. The zymographic pattern of gelatinolytic activity of the HAM did not undergo a change during passages. When the HAM were cultured in a fibronectin-coated dishes in a hepatogenic medium, there was no significant difference of the gelatinase pattern between before and after culture. However, when bFGF was added to the culture, a dramatic increase of 62kDa and 59kDa gelatinases was observed. Interestingly, when ITS instead of FN was present, HAM-conditioned medium also showed a similar increase of both gelatinases. Immunoblotting analysis demonstrated that both 62kDa and 59kDa gelatinases were the active form of MMP-2 resulting from the turnover of MMP-2 proform. Futher study will be necessary to determine the relationship between bFGF and active MMP-2 during hepatogenesis of HAM.
        4,000원
        919.
        2005.12 구독 인증기관 무료, 개인회원 유료
        This study was conducted to test whether the transgenic cattle pass the transgene to their progeny through germ cells, and whether the transgene is expressed in the mammary gland of ransgenic cows. Two male ransgenic calves were born from IVF-derived embryos injected with bovine β-casein/human lactoferrin fusion gene and then grew up to be reproducible. Semen was collected from a transgenic bull after 18 mon of age and then frozen. Bovine oocytes matured in vitro were fertilized with spermatozoa of the transgenic bull and cultured in 50㎕ drops of CRlaa medium supplemented with 3 mg/mL BSA. After 48 h of culture, cleaved embryos were determined for the presence of transgenes by DNA polymerase chain reaction (PCR). Proportion of transgene positives among bovine embryos fertilized with sperm of the transgenic bull was 20.9% (28/134). One of transgenic bulls did not produce transgenic sperm. Out of 34 calves produced from recipient heifers inseminated with semen of the other bull, 3 (8.8%) were transgenic animals (2 females and 1 male). Thus, one transgenic bull showed a low transmission frequency below Mendelian levels in both the IVF-derived embryos and his progeny. It was demonstrated by Southern blot that copy numbers of the transgene in the transgenic progeny enhanced about 1.8 times as compared to those of the founder bull The results demonstrate that the transgenic bull carrying human lactoferrin gene could pass his transgene to the progeny through germ cells, although he is a germ-line mosaic.
        4,000원