• Title/Summary/Keyword: p-cycle

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Protein kinase와 cell cycle

  • 유일재
    • The Microorganisms and Industry
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    • v.19 no.2
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    • pp.2-10
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    • 1993
  • 이 총론에서는 cell cycle의 조절에 관계하는 p34cdc kinase의 특성과 기질 그리고 cell cycle에서의 역할을 살펴보고, 또 cell cycle에서와 여러가지 세포내의 현상에 중요한 역할을 하는 것으로 알려진 casein kinase II의 특성과 기질 그리고 cell cycle에서의 역할을 살펴보고자 한다. 그리고 이런 효소들을 연구하는 데 필수적인 방법이나 시약들로 소개하고자 한다.

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Celecoxib, a COX-2 Selective Inhibitor, Induces Cell Cycle Arrest at the G2/M Phase in HeLa Cervical Cancer Cells

  • Setiawati, Agustina
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.1655-1659
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    • 2016
  • Celecoxib, a selective inhibitor of COX-2, showed cytotoxic effects in many cancer cell lines including cervical cancer cells. This study investigated the effect of celecoxib on cell cycle arrest in HeLa cervical cancer cells through p53 expression. In vitro anticancer activity was determined with the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) method. A double staining method was applied to investigate the mechanism of cell death, cell cycling was analyzed by flow cytometryand immunocytochemistry was employed to stain p53 expression in cells. Celecoxib showed strong cytotoxic effects and induced apoptosis with an $IC_{50}$ value of $40{\mu}M$. It induced cell cycle arrest at G2/M phase by increasing level of p53 expression on HeLa cells.

Performance Analysis of a Combined Power Cycle Utilizing Low-Temperature Heat Source and LNG Cold Energy (저온 열원 및 LNG 냉열을 이용하는 복합 발전 사이클의 성능 해석)

  • Kim, Kyoung-Hoon;Oh, Jae-Hyeong;Ko, Hyung-Jong
    • Transactions of the Korean hydrogen and new energy society
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    • v.23 no.4
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    • pp.382-389
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    • 2012
  • Power generation cycle using ammonia-water mixture as working fluid has attracted much attention because of its ability to efficiently convert low-temperature heat source into useful work. If an ammonia-water power cycle is combined with a power cycle using liquefied natural gas (LNG), the conversion efficiency could be further improved owing to the cold energy of LNG at $-162^{\circ}C$. In this work parametric study is carried out on the thermodynamic performance of a power cycle consisted of an ammonia-water Rankine cycle as an upper cycle and a LNG cycle as a bottom cycle. As a driving energy the combined cycle utilizes a low-temperature heat source in the form of sensible heat. The effects on the system performance of the system parameters such as ammonia concentration ($x_b$), turbine 1 inlet pressure ($P_{H_1}$) and temperature ($T_{H_1}$), and condenser outlet temperature ($T_{L_1}$) are extensively investigated. Calculation results show that thermal efficiency increases with the increase of $P_{H_1}$, $T_{H_1}$ and the decrease of $T_{L_1}$, while its dependence on $x_b$ has a downward convex shape. The changes of net work generation with respect to $P_{H_1}$, $T_{H_1}$, $T_{L_1}$, and $x_b$ are roughly linear.

Multiple linear regression model-based voltage imbalance estimation for high-power series battery pack (다중선형회귀모델 기반 고출력 직렬 배터리 팩의 전압 불균형 추정)

  • Kim, Seung-Woo;Lee, Pyeong-Yeon;Han, Dong-Ho;Kim, Jong-hoon
    • Journal of IKEEE
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    • v.23 no.1
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    • pp.1-8
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    • 2019
  • In this paper, the electrical characteristics with various C-rates are tested with a high power series battery pack comprised of 18650 cylindrical nickel cobalt aluminum(NCA) lithium-ion battery. The electrical characteristics of discharge capacity test with 14S1P battery pack and electric vehicle (EV) cycle test with 4S1P battery pack are compared and analyzed by the various of C-rates. Multiple linear regression is used to estimate voltage imbalance of 14S1P and 4S1P battery packs with various C-rates based on experimental data. The estimation accuracy is evaluated by root mean square error(RMSE) to validate multiple linear regression. The result of this paper is contributed that to use for estimating the voltage imbalance of discharge capacity test with 14S1P battery pack using multiple linear regression better than to use the voltage imbalance of EV cycle with 4S1P battery pack.

Characterization of a Putative F-box Motif in Ibd1p/Bfalp, a Spindle Checkpoint Regulator of Budding Yeast Saccharomyces cerevisiae

  • Lee, Kyum-Jung;Hyung-Seo;Kiwon Song
    • Journal of Microbiology
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    • v.39 no.4
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    • pp.286-292
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    • 2001
  • During mitosis. the proper segregation of duplicated chromosomes is corrdinated by a spindle check-point. The bifurcated spindle checkpoint blocks cell cycle progression at metaphase by monitoring unattached kinetochores and inhibits mitotic exit in response to the misorientation of the mitotic spin- dle Ibd1p/Bfa1p is a spindle checkpoint regulator of budding yeast in the Bub2p checkpoint pathway for mitotic exit and its disruption abolishes mitotic arrest when proper organization of the mitotic spin-dls inhibited. Ibd1p/Bfa1p localizes to the spindle pole body, a microtublue-organizing center in yeast, and its overexpression arrests the cell cycle in 80% of cells with an enlarged budy at mitosis and in 20 % of cells with multiple buds. In this study, we found that the C-terminus of Ibd1p/Bfa1p phys-ically interacts with Skp1p, a key component of SCF (Skp1/cullin/F-box) complex for ubiquition-medi-ated proteolysis of cel cycle regulatores as well as an evolutionally conserved kinetochore protein for cell cycle progression. A putative F-box motif was found in the C-terminus of Ibd1p/Bfa1p and its function was investigated by making mutants of conserved residues in the motif. These Ibd1p/Bfa1p mutants of a putative F-box interacted with SKp1p in vitro by two-hybrid assays as wild type Ibd1p/Bfa1p. Also these Ibd1p/Bfa1p utants displayed the overexpression phenotypes of wild type Ibd1p, when over-expressed under inducible promoters . These results suggest that a putative F-box motif of Ibd1p/Bfa1p is not essential for the interaction with SKp1p and its function in mitotic exit and cytokinesis.

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Connexin32 inhibits gastric carcinogenesis through cell cycle arrest and altered expression of p21Cip1 and p27Kip1

  • Jee, Hyang;Lee, Su-Hyung;Park, Jun-Won;Lee, Bo-Ram;Nam, Ki-Taek;Kim, Dae-Yong
    • BMB Reports
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    • v.46 no.1
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    • pp.25-30
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    • 2013
  • Gap junctions and their structural proteins, connexins (Cxs), have been implicated in carcinogenesis. To explore the involvement of Cx32 in gastric carcinogenesis, immunochemical analysis of Cx32 and proliferation marker Ki67 using tissue-microarrayed human gastric cancer and normal tissues was performed. In addition, after Cx32 overexpression in the human gastric cancer cell line AGS, cell proliferation, cell cycle analyses, and $p21^{Cip1}$ and $p27^{Kip1}$ expression levels were examined by bromodeoxyuridine assay, flow cytometry, real-time RT-PCR, and western blotting. Immunohistochemical study noted a strong inverse correlation between Cx32 and Ki67 expression pattern as well as their location. In vitro, overexpression of Cx32 in AGS cells inhibited cell proliferation significantly. $G^1$ arrest, up-regulation of cell cycle-regulatory proteins $p21^{Cip1}$ and $p27^{Kip1}$ was also found at both mRNA and protein levels. Taken together, Cx32 plays some roles in gastric cancer development by inhibiting gastric cancer cell proliferation through cell cycle arrest and cell cycle regulatory proteins.

The Effect of Cycle Ergometer Exercise Inducing Movement of the Affected Side on Knee Joint Function after Total Knee Arthroplasty (환측사용유도 고정식자전거운동이 무릎관절 기능에 미치는 영향: 무릎인공관절수술 환자를 대상으로)

  • Choi, Eun-Ji;Lee, Sang-Yeol
    • PNF and Movement
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    • v.20 no.1
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    • pp.91-101
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    • 2022
  • Purpose: The purpose of this study was to examine the effect of cycle ergometer exercise inducing movement of the affected side on knee joint function after total knee arthroplasty (TKA). Methods: The primary experiment was conducted on 19 members of the cycle ergometer exercise group to measure the muscle activity of the rectus femoris, hamstring, tibialis anterior, and gastrocnemius muscles during cycle ergometer exercise that induced the affected side's movement. In the second experiment, after receiving physiotherapeutic intervention for 30 min, the general bicycle exercise group and cycle ergometer exercise group performed the corresponding exercise for 15 min, 5 times per week, for 2 weeks. The ROM, muscle strength, pain, and balance were then measured and compared between the two groups. Results: In the results of the primary experiment, cycle ergometer exercise inducing movement of the affected side showed a significantly larger increase in the activity of leg muscles (rectusfemoris, hamstring, tibialis anterior, gastrocnemius) on the affected side than the general bicycle exercise (p <0.05). In the second experiment, the cycle ergometer exercise group showed a significantly larger increase in range of movement of affected side knee flexion and muscle strength of affected side knee flexion, knee extension, and plantarflexion than the general bicycle exercise (p <0.05). No significant between-group difference was observed in pain and balance before or after the intervention (p >0.05). Conclusion: Cycle ergometer exercise inducing movement of the affected side increases use of the muscles around the affected side knee joint after TKA more than general bicycle exercise and produces better effects for enhancing muscle strength. The application of cycle ergometer exercise inducing movement of the affected side is expected to reduce the patients' unbalanced use during the early postoperative period and help them to quickly return to normal daily life through rapid muscle strength recovery.

Photochemical Response in 0-Year-Old and 1-Year-Old Needles of Picea glehnii during Cold Acclimation and Low Temperature

  • Bae, Jeong-Jin;Hara, Toshihiko;Choo, Yeon-Sik
    • Journal of Ecology and Environment
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    • v.31 no.4
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    • pp.317-325
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    • 2008
  • P. glehnii, an evergreen conifer found in northern areas, is known as a cold-resistant species. In this experiment, we measured the water content, PSⅡ efficiency, chlorophyll fluorescence, pigments of the xanthophyll-cycle and activity of enzymes of the ascorbate-glutathione cycle during cold acclimation and at subsequent low-temperature conditions to examine the importance of acclimation to cold tolerance. P. glehnii showed a decrease in PSⅡ efficiency (especially in Fv) during cold acclimation and at subsequent low temperatures. However, cold-acclimated needles showed higher PSⅡ efficiency at low temperatures than nonacclimated needles. In addition, 0-YON (first-year needles) showed an increase in $\beta$-carotene and lutein, while 1-YON (one-year-old needles) immediately developed an antioxidant mechanism in the ascorbate-gluthathione cycle as soon as they were exposed to low temperature and both 0-YON and 1-YON showed increased zeaxanthin and de-epoxidation ratios at continuous low temperature. Based on our results, we suggest that P. glehnii maintain PSⅡ efficiency at low temperature by effectively protecting the photosynthetic apparatus from photo-damage by rapid induction of an antioxidant mechanism in 1-YON and dissipation of excess energy by $\beta$-carotene and lutein in 0-YON.

Kaempferol induced the apoptosis via cell cycle arrest in human breast cancer MDA-MB-453 cells

  • Choi, Eun-Jeong;Ahn, Woong-Shick
    • Nutrition Research and Practice
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    • v.2 no.4
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    • pp.322-325
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    • 2008
  • The aim of present study was to investigate the effects of kaempferol on cellular proliferation and cell cycle arrest and explore the mechanism for these effects in human breast carcinoma MDA-MB-453 cells. Cells were treated with kaempferol at various concentrations (ranging from 1 to $200\;{\mu}M$) for 24 and 48 hrs. Kaempferol significantly inhibited cancer cell growth in cells exposed to 50 and $10\;{\mu}M$ of kaempferol and incubated for 24 and 48 hrs, respectively. Exposure to kaempferol resulted in cell cycle arrest at the G2/M phase. Of the G2/M-phase related proteins, kaempferol down-regulated CDK1 and cyclin A and B in cells exposed to kaempferol. In addition, small DNA fragments at the sub-G0 phase were increased by up to 23.12 and 31.90% at 10 and $50\;{\mu}M$ incubated for 24 and 48 hrs, respectively. The kaempferol-induced apoptosis was associated with the up-regulation of p53. In addition, the phosphorylation of p53 at the Ser-15 residue was observed with kaempferol. Kaempferol inhibits cell proliferation by disrupting the cell cycle, which is strongly associated with the induction of arrest at G2/M phase and may induce apoptosis via p53 phosphorylation in human breast carcinoma MDA-MB-453 cells.

Integrating Concept Mapping and the Learning Cycle to Teach Genetics and Reproduction to High School Students (고등학생들의 생물학습에서 개념도와 순환학습을 통합한 수업의 효과)

  • Chung, Young-Lan;Lee, Eun-Pa
    • Journal of The Korean Association For Science Education
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    • v.23 no.6
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    • pp.617-626
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    • 2003
  • Although many studies have investigated the effectiveness of concept mapping and the learning cycle, in Korea none have explored the effectiveness of concept mapping and the learning cycle combined. This study explored the effectiveness of concept mapping, the learning cycle, and a combination of concept mapping/learning cycle(CL) in high school biology class. Students' science achievement, the science related attitudes and scientific inquiry ability was measured. The results indicated that concept mapping, the learning cycle, and CL treatment were significantly different from the traditional one in science achievement(p< .05). However, the three treatments were not significantly different from each other. No significant difference exists among different learnings in high and average-ability students. But, concept mapping was the most effective in low-ability students. For the students' scientific inquiry ability, CL and learning cycle were more effective than concept mapping and traditional learning. No significant difference exists among different learnings in high-ability students. CL and learning cycle were more effective than concept mapping and traditional learning in average and low-ability students. For the students' science related attitudes, concept mapping, the learning cycle, and CL were more effective than the traditional learning. But, there was no significant difference among these three groups.