• 한국정밀공학회지
• /
• 제16권3호통권96호
• /
• pp.222-232
• /
• 1999

This paper describes the development of a precision 3-component load cell with plate beams which may be used for measuring forces Fx, Fy and moment Mz simultaneously in industry. We have derived equations to predict the bending strains on the surface of the beams under forces or moment. We have also determined the attachment location of strain gages of each sensor and fabricated 3-component load cell. To evaluate the rated strain and interference error of each sensor, we have carried out characteristic test of precision 3-component load cell. It reveals that the rated strain calculated from the derived equations are good agreement with the results from Finite Element Method analysis.

• 대한금속재료학회지
• /
• 제46권12호
• /
• pp.809-816
• /
• 2008

The influences of various parameters such as inclusions, surface roughness, exposed areas and chloride ion concentrations on the initiation of pitting of Fe-17Cr alloy were investigated, using micro-droplet cell technique. Micro-droplet cell allows one to align the micro-electrode to the desired spot of the working electrode and measure directly local currents with the potentiodynamic polarization. Micro electrochemical tests were carried out at the inclusions after EDX analysis of inclusion. EDX analysis identified inclusions as Cr-oxides. It was found that some active inclusions among Cr-oxide inclusions acted as initiation sites for pitting corrosion. In addition, the rougher surface and the denser chloride ion concentration offered easier pit initiation sites, causing the more susceptible to pitting corrosion.

• 한국자기공명학회논문지
• /
• 제23권1호
• /
• pp.33-39
• /
• 2019

Studies on the interactions of proteins with partner molecules at the atomic resolution are essential for understanding the biological function of proteins in cells and for developing drug molecules. Solution NMR spectroscopy has shown remarkably useful capability for investigating properties on the weak to strong intermolecular interactions in both diluted and crowded solution such as cell lysates. Of note, the state-of-the-art in-cell NMR method has made it possible to obtain atomistic information on natures of intermolecular interactions between target proteins with partner molecules in living cells. In this mini-review, we comprehensively describe the several technological advances and developments in the in-cell NMR spectroscopy.

• Journal of Acupuncture Research
• /
• 제19권4호
• /
• pp.74-88
• /
• 2002

Objectives : This study is aimed to investigate the effects of bee venom and melittin on cell death in synovial cell line. Methods : It was evaluated by using MTT assay, morphologic method, DNA fragmenation, NO generation, flow cytometry, immunocytochemistry analysis, RT-PCR, Western blot. Results : The obtained results are summarized as follows: 1. The MTT assay demonstrated that synovial cell viability was significantly inhibitted dose-dependently by treatment with bee venom and melittin in comparison with control. 2. The morphologic study demonstrated that synovial cell showed apoptosis after treatment with bee venom and melittin for 6 hours using microscope. 3. In case of NO generation bee venom group and melittin group showed significant inhibition in comparison with control. 4. The Flow cytometry demonstrated that apoptosis of synovial cell treated with bee venom and melittin was related with stop of cell cycle in stage of $G_0/G_1$. 5. DNA fragmenation demonstrated that synovial cell treated with bee venom and melittin showed DNA ladder below l Kbp. 6. Immunocytochemistry assay demonstrated that COX-II and PLA2 were strongly down-regulated by treatment with bee venom and melittin whereas iNOS was almostly not expressed by bee venom treatment and slightly expressed by melittin treatment. 7. RT-PCR analysis demonstrated that iNOS were strongly down-regulated by treatment with bee venom and melittin whereas COX-II was almostly not expressed by bee venom treatment and slightly expressed by melittin treatment. 8. Western blot demonstrated that iNOS were strongly down-regulated by treatment with $15{\mu}g/ml$ bee venom whereas COX-II was strongly down-regulated from $5{\mu}g/ml$ bee venom. Conclusions : These results suggest that bee venom and melittin have significant effect on cell death in synovial cell line and further study is needed in vivo.

• 한국동물학회지
• /
• 제33권4호
• /
• pp.446-453
• /
• 1990

본 실험은 레티노익산에 의해 F9 Teratocarcinoma Stem Cell의 분화를 유도하고 이분화과정에서 세포형태의 변화와 라미닌유전자의 발현을 조사 하였다. 분화되지 않은 F9 Stem Cell은 지속적으로 증식을 하며 세포간의 간격을 구분하기 어령루 뿐만 아니라 불규칙적인 모양을 하고 있으나,레티노익산과 dibutyryl cyclic AMP처리후의 분화된 F9세포는 둥글고 평평한 모양을 나타내며 세포성장은 중지되었다. Northern blot분석에 의하여 레티노익산과 cyclic AMP처리 후의 F9세포내에서 라미닌 유전자의 발현은 현저하게 증가하였다. 즉, 라미닌 B1유전자 발현은 분화과정 동안 최소한 30배, 라미닌 B2 유전자의 발현은 약 20배 증가하였다. 또한 라미닌 항체를 이용한 면역형광 분석결과는 Northern 분석결과와 일치하게 분화 후에 라미닌 단백질 합성이 크게 증가되었으며, 생성된 라미닌 단백질은 거의 세포표면에 분포된 것으로 나타났다. 이러한 결과로부터, 레티노익산에 의해 F9 Stem Cell의 분화가 유도되며 이 분화과정에서의 형태적인 변화와 진행은 라미닌의 생성과 밀접한 관련이 있다고 추측된다.

• KSBB Journal
• /
• 제16권6호
• /
• pp.579-591
• /
• 2001

The cell growth inhibitor effect of cervical cancer cells was investigated by liposome mediated transfection (pRcCMVp53/lipofectin) and by transfection using adenovirus (AdCMVp57). The papilloma virus cancer cell lines we used in this study were HPV16 positive, having inhibiter gene, wild p53 gene, CaSki, SiHa, HPV18 positive HeLa, HeLaS3 and HPV negative C33A, HT3. LacZ gene of E.coli was used as the marker gene for the transfection efficiency. The effect on the inhibition of tumor cell growth was measured by cell count and cell viability though ELISA analysis and MTT assay. The inhibition of tumor cell growth was confirmed by measuring each assay for six days, comparing with the normal control cell growth. The cell growth of cervical cancer calls by transfection was significantly reduced and showed tittle differences among the cell lines. To eliminate the potential problem of Ad(adenovirus) contamination during rAAV production, rAAV can be produced by a triple transfection of vector plasmic, packaging plasmid, and adenovirus helper plasmid. To examine the helper functions of Ad plasmids on the production of rAAV vector, we carried out cotransfection of three plasmids, AAV vector, packaging construct, and Ad helper plasmids. The optimized transfection condition for calcium phosphate method is 25ug of total DNA per 10-cm-diameter plate of 293 cell. We found that rAAV yields peaked at 48hr after Ad infection. The titer of rAAV was measured by the dot blot analysis to measure the number of particles/ml based on the quantification of viral DNA. Recent1y, Kombucha(fungi) was identified as a very potent antileukefic agent. In the present study, effect of natural toxin(plankton) and Kombucha is PSP(GTXI-3, neoSTX), on various MTT assay cervical cancer cell line. Toxin(GTX 1-3, neoSTX) also inhibited the proliferation in primary cervical cancer calls in a dose-dependent toxin concentration. These results showed that toxin was very potent in inhibiting the proliferation of cervical cancer calls in vitro. Toxins and Kombuoha exhibited a dose dependent inhibition of cellular proliferation in cancer cell line.

• Bulletin of the Korean Chemical Society
• /
• 제35권12호
• /
• pp.3475-3481
• /
• 2014

This paper describes how primary contaminants in ambient air affect the performance of the cathode in fuel cell electric vehicle applications. The effect of four atmospheric pollutants ($SO_2$, $NH_3$, $NO_2$, and CO) on cathode performance was investigated by air impurity injection and recovery test under load. Electrochemical analysis via polarization and electrochemical impedance spectroscopy was performed for various concentrations of contaminants during the impurity test in order to determine the origins of performance decay. The variation in cell voltage derived empirically in this study and data reported in the literature were normalized and juxtaposed to elucidate the relationship between impurity concentration and performance. Mechanisms of cathode degradation by air impurities were discussed in light of the findings.

• Journal of Acupuncture Research
• /
• 제19권2호
• /
• pp.28-38
• /
• 2002

Objective : This study is aimed to investigate the effects of bee venom and purified bee venom on cell death in synovial cell line. Methods : It was evaluated by using MTT assay, morphological method, flow cytometry, immunocytochemistry analysis, RT-PCR. Results : The result obtained is as follows. 1. The MTT assay demonstrated that synovial cell viability was significantly inhibitted dose-dependently by treatment with BV and PBV in comparison with control. And the inhibitory effect of BV and PBV was almost same. 2. The morphologic study demonstrated that synovial cell showed apoptotic body resulted from apoptosis after treatment with BV and PBV for 6 hours using microscope. 3. The Flow cytometry demonstrated that apoptosis of synovial cell treated with BV and PBV was related with stop of cell cycle in stage of G0/G1. 4. Immunocytochemistry assay demonstrated that COX-II and iNOS were slightly expressed by treatment with BV and PBV in comparison with control group. 5. RT-PCR analysis demonstrated that COX-II were almost down-regulated by high dose treatment with BV and PBV in comparison with control group. iNOS were well down-regulated by treatment with $5{\mu}g/ml$ BV and PBV whereas it was well expressed in control group. Conclusion : These results suggest that bee venom and purified bee venom have significant effect on cell death in synovial cell line and further study is needed in vivo.

• 대한한방부인과학회지
• /
• 제19권2호
• /
• pp.214-225
• /
• 2006

Purpose : This study was aimed to investigate the inhibitory effect of Corydalis Tuber on the proliferation of human uterine leiomyoma cell and the expression of gene related the mechanism of cell apoptosis. Methods : We counted the number of suvival cells treated with indicated concentration of Corydalis Tuber and investigated cell viability by MTS assay. Furthermore, flow cytometric analyis were used to dissect between necrosis and apoptosis related with cell cycle and then we observed the differential gene expression by western blot analysis. Results : 1) The inhibitory effect on the proliferation of uterine leiomyoma cell treated with Corydalis Tuber was increased in a concentration and time proportional. 2) The result of flow cytometry analysis, subG1 phase arrest related cell apoptosis was not investigated in uterine leiomyoma cell treated Corydalis Tuber but showed G2/M phase prolongation. 3) The gene expression of p27, p21 related cell cycle was increased according to increasing concentration, but p53 was not exchanged. 4) The dephosphorylation of pRb gene were increased dependent on treatment concentration and pro-caspase 3, CDK4 were not exchanged. Conclusion : This study showed that Corydalis Tuber have the inhibitory effect on the proliferation of human uterine leiomyoma cell but the effect was thoughted no relationship with apoptosis. The inhibitory effect was suggested that dephosphorylation of pRb gene induced with increasing p21, p27 prolonged cell division in G2/M phase.

• 한국통신학회논문지
• /
• 제25권9A호
• /
• pp.1431-1440
• /
• 2000

원격 회의, 원격 교육, 원격 진료 등의 서비스를 제공하기 위해서는 하부 통신망에서 multipoint-to-multipoint(MP-to-MP) 연결을 효과적으로 제공해야만 한다. 최근의 연구결과들에 의하면 MP-to-MP 연결 설정 및 관리를 위하여 shared tree를 사용하는 것이 효과적인 것으로 분석되고 있다. 본 논문에서는 ATM망에서 MP-to-MP 통신 구현 시 필요한 shared tree 기반의 VC 다중화 방안으로서 CIMA(Cell Insterleaved Multiplexing on ATM) 기법을 제안한다. CIMA 방식에서는 다중화가 발생하는 경우 MRM(Multicast RM) cell을 이용하여 다중화 정보를 다음 노드로 전달한다. 수신자는 MRM cell에 담긴 다중화 정보를 이용하여 동일한 VPI/VCI를 사용하는 채널로 들어온 cell들의 송신측을 구분할 수 있으므로 VC 다중화에서 발생하는 CIP(Cell Interleaving Problem)를 해결할 수 있다.