• Title/Summary/Keyword: cell cycle control

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The Structure of a Powered Knee Prosthesis based on a BLDC Motor and Impedance Control using Torque Estimation on Free Swing (BLDC 모터 기반 동력 의족의 구성과 토크 추정을 활용한 유각기의 임피던스 제어)

  • Gyeong, Gi-Yeong;Kim, Jin-Geol;Lee, Young-Sam
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.5
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    • pp.407-412
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    • 2015
  • This paper presents the design of a lab-built powered knee prosthesis based on a BLDC motor, a sensored impedance control using a force sensor, and a sensorless impedance control through torque estimation. Firstly, we describe the structure of the lab-built powered knee prosthesis and its limitations. Secondly, we decompose the gait cycle into five stages and apply the position-based impedance control for the powered knee prosthesis. Thirdly, we perform an experiment for the torque estimation and the sensorless impedance control of the prosthesis. The experimental results show that we can use the torque estimation to control the low impedance during the swing phase, although the estimated torque data has a delay compared with the measured torque by a load cell.

The Effect of Bee Venom & Melittin Solution on Cell Death in Synovial Cell Line (봉독(蜂毒) 및 Melittin 약침액(藥鍼液)이 관절염(關節炎) 활액세포(滑液細胞)에 미치는 영향(影響))

  • Han, Sang-won;Park, Ki-hyeon;Jung, Tae-young;Seo, Jung-chul
    • Journal of Acupuncture Research
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    • v.19 no.4
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    • pp.74-88
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    • 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.

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Design and Implementation of Modified Current Source Based Hybrid DC - DC Converters for Electric Vehicle Applications

  • Selvaganapathi, S.;Senthilkumar, A.
    • Transactions on Electrical and Electronic Materials
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    • v.17 no.2
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    • pp.57-68
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    • 2016
  • In this study, we present the modern hybrid system based power generation for electric vehicle applications. We describe the hybrid structure of modified current source based DC - DC converters used to extract the maximum power from Photovoltaic (PV) and Fuel Cell system. Due to reduced dc-link capacitor requirement and higher reliability, the current source inverters (CSI) better compared to the voltage source based inverter. The novel control strategy includes Distributed Maximum Power Point Tracking (DMPPT) for photovoltaic (PV) and fuel cell power generation system. The proposed DC - DC converters have been analyzed in both buck and boost mode of operation under duty cycle 0.5>d, 0.5<d<1 and 0.5<d for capable electric vehicle applications. The proposed topology benefits include one common DC-AC inverter that interposes the generated power to supply the charge for the sharing of load in a system of hybrid supply with photovoltaic panels and fuel cell PEM. An improved control of Direct Torque and Flux Control (DTFC) based induction motor fed by current source converters for electric vehicle.In order to achieve better performance in terms of speed, power and miles per gallon for the expert, to accepting high regenerative braking current as well as persistent high dynamics driving performance is required. A simulation model for the hybrid power generation system based electric vehicle has been developed by using MATLAB/Simulink. The Direct Torque and Flux Control (DTFC) is planned using Xilinx ISE software tool in addition to a Modelsim 6.3 software tool that is used for simulation purposes. The FPGA based pulse generation is used to control the induction motor for electric vehicle applications. FPGA has been implemented, in order to verify the minimal error between the simulation results of MATLAB/Simulink and experimental results.

Sphingolipid Metabolic Changes during Chiral C2-Ceramides Induced Apoptosis in Human Leukemia Cells

  • Baek, Mi-Young;Yoo, Hwan-Soo;Kazuyasu Nakaya;Moon, Dong-Cheul;Lee, Yong-Moon
    • Archives of Pharmacal Research
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    • v.24 no.2
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    • pp.144-149
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    • 2001
  • N-acetylsphingosine (C2-ceramide) is a synthetic water-soluble ceramide mimicking the activity of natural ceramides. By fixing chiral conformation on carbon numbers 2 and 3 in the ceramide structure, four chiral C2-ceramides naming d-erythro-, I-erythro-, d-threo-and 1-three C2-ceramide were synthesized. We have investigated the chiral effects of these C2-ceramides on the sphingolipid metabolism, particularly on both the sphingolipid bio- synthetic pathway and on the degradation pathway. In both HL-60 and U937 cells, the chiral C2-ceramide ($10{\mu}\textrm{m}$) showed sphingosine accumulation monitored fluoromatrically by a high performance liquid chromatographic separation of the sphingoid bases. Most importantly, in HL-60 cells, l-erythro C2-ceramide induced a 50 fold increase in sphingosine as compared to the control, while l-threo C2-ceramide exhibited a minimal 7-fold in-crease. In contrast, sphinganine, another sphingoid base, showed less accumulation by any chiral C2-ceramide tested under the same conditions. These results suggested that chiral C2-ceramide primarilyacts on the sphingolipid degradation pathway rather than on the sphingolipid biosynthetic route. The strong $C_0/G_1$ phase arrest in the cell cycle by treatment of I-erythro C2-ceramide indicates that the blockade of the sphingolipid degradation pathway might be concomitantly involved in the dysfunction of the cell cycle. On the other hand, the fact that all chiral C2-ceramides tested failed to inhibit the activity of sphingosine kinase acting on the removal of sphingosine by producing sphingosine-1 -phosphate demonstrates that chiral C2- ceramides may increase sphingosine by activating various ceramidases by which natural ceramides are divided into sphingosine and free fatty acids. However, the precise steps involved in this interaction are still unknown.

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The Membrane-Bound Form of IL-17A Promotes the Growth and Tumorigenicity of Colon Cancer Cells

  • Thi, Van Anh Do;Park, Sang Min;Lee, Hayyoung;Kim, Young Sang
    • Molecules and Cells
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    • v.39 no.7
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    • pp.536-542
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    • 2016
  • Interleukin-17A is a member of the IL-17 family, and is known as CTLA8 in the mouse. It is produced by T lymphocytes and NK cells and has proinflammatory roles, inducing cytokine and chemokine production. However, its role in tumor biology remains controversial. We investigated the effects of locally produced IL-17A by transferring the gene encoding it into CT26 colon cancer cells, either in a secretory or a membrane-bound form. Expression of the membrane-bound form on CT26 cells dramatically enhanced their proliferation in vitro. The enhanced growth was shown to be due to an increased rate of cell cycle progression: after synchronizing cells by adding and withdrawing colcemid, the rate of cell cycle progression in the cells expressing the membrane-bound form of IL-17A was much faster than that of the control cells. Both secretory and membrane-bound IL-17A induced the expression of Sca-1 in the cancer cells. When tumor clones were grafted into syngeneic BALB/c mice, the tumor clones expressing the membrane-bound form IL-17A grew rapidly; those expressing the secretory form also grew faster than the wild type CT26 cells, but slower than the clones expressing the membrane-bound form. These results indicate that IL-17A promotes tumorigenicity by enhancing cell cycle progression. This finding should be considered in treating tumors and immune-related diseases.

The Study of Anti-cancer Mechanism with Bee Venom and Melittin on Human Prostatic Cancer Cell (전립선 암세포에 대한 봉약침액(蜂藥浸液) 및 Melittin 약침액(藥浸液)의 항암(抗癌) 기전(機轉) 연구(硏究))

  • Kim, Kyung-Tae;Song, Ho-Sueb
    • Journal of Acupuncture Research
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    • v.22 no.6
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    • pp.37-50
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    • 2005
  • Objectives : The purpose of this study was to investigate the anti-caner effect of Bee Venom and Melittin on the prostatic cancer cell(PC-3). The goal of study is to ascertain whether Bee Venom and Melittin inhibits the cell growth and cell cycle of PC-3, or the expression of relative genes and whether the regression of PC-3 cell growth is due to cell death or the expression of gene related to apoptosis. Methods : After the treatment of Pc-3 cells with Bee Venom and Melittin, we performed Fluorescence microscope, MTT assay, Western blotting, Flow cytometry, PAGE electrophoresis and Surface plasmon resonance analysis to identify the cell viability, apoptosis and gene related to apoptosis. Results : 1. Compared with Control cell, the inhibition of cell growth reduced in proportion with the dose of Bee Venom or Melittin($0{\sim}10{\mu}g/ml$) in PC-3. 2. In PC-3, Cell viabilities of Bee Venom or Melittin treatment was decreased significantly. 3. The nucli of Control cells were stained round and homogenous in DAPI staining, but those of PC-3 were stained condense and splitted. 4. In PC-3, apoptosis of Bee Venom or Melittin treatment was increased significantly. 5. Bax, Caspase-3 and P ARP of Bee Venom or Melittin treatment was increased significantly and Bcl-2 of Bee Venom or Melittin treatment was decreased significantly. Caspase-9 of Bee venom treatment was increased significantly. Conclusion : These results indicate that Bee Venom and Melittin inhibits the growth of prostate cancer cells, has anti-cancer effects by inducing apoptosis. We wish that the anti-cancer effects of Bee Venom and Melittin are used to clinical caner treatment.

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Primary Cilium by Polyinosinic:Polycytidylic Acid Regulates the Regenerative Migration of Beas-2B Bronchial Epithelial Cells

  • Gweon, Bomi;Jang, Tae-Kyu;Thuy, Pham Xuan;Moon, Eun-Yi
    • Biomolecules & Therapeutics
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    • v.30 no.2
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    • pp.170-178
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    • 2022
  • The airway epithelium is equipped with the ability to resist respiratory disease development and airway damage, including the migration of airway epithelial cells and the activation of TLR3, which recognizes double-stranded (ds) RNA. Primary cilia on airway epithelial cells are involved in the cell cycle and cell differentiation and repair. In this study, we used Beas-2B human bronchial epithelial cells to investigate the effects of the TLR3 agonist polyinosinic:polycytidylic acid [Poly(I:C)] on airway cell migration and primary cilia (PC) formation. PC formation increased in cells incubated under serum deprivation. Migration was faster in Beas-2B cells pretreated with Poly(I:C) than in control cells, as judged by a wound healing assay, single-cell path tracking, and a Transwell migration assay. No changes in cell migration were observed when the cells were incubated in conditioned medium from Poly(I:C)-treated cells. PC formation was enhanced by Poly(I:C) treatment, but was reduced when the cells were exposed to the ciliogenesis inhibitor ciliobrevin A (CilioA). The inhibition of Beas-2B cell migration by CilioA was also assessed and a slight decrease in ciliogenesis was detected in SARS-CoV-2 spike protein (SP)-treated Beas-2B cells overexpressing ACE2 compared to control cells. Cell migration was decreased by SP but restored by Poly(I:C) treatment. Taken together, our results demonstrate that impaired migration by SP-treated cells can be attenuated by Poly(I:C) treatment, thus increasing airway cell migration through the regulation of ciliogenesis.

Effects of Duchesnea indica on Human Stomach Cancer Cells(KATOIII) (사매의 KATOIII 위암세포(胃癌細胞)에 대(對)한 항암효능(抗癌效能))

  • Lim, Joong-Hwa;Kim, Jin-Sung;Yoon, Sang-Hyub;Ryu, Ki-Won;Ryu, Bong-Ha
    • The Journal of Internal Korean Medicine
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    • v.26 no.2
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    • pp.302-309
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    • 2005
  • Background : Death by cancer, malignant tumor, is on the increase around the world. In South Korea, cancer is the number one cause of death, and, in South Korea, stomach cancer is the most common form of cancer. This may be due to genetic and enviornmental factors. Because stomach cancer is so prevalent here, this study was undertaken. Objectives: This study was conducted to investigate the anti-cancer effects of Duchesnea indica(Andr.) Focke. in human stomach cancer cells(KATOIII). Materials & Methods: For human stomach cancer cells KATO III cells were obtained from Korea Cell Line Bank. The water decoction of Duchesnea indica(Andr.) Focke was added to cultures. First, morphological changes were examined under an inverted microscope. The destruction of stomach cancer cells was measured through Trypan blue exclusion testing, and suppression of viability of stomach cancer cells was measured via MTT assay. Anti-cancer mechanisms were assessed by analyzing the cell cycle. Results & Conclusions : In morphologic change, stomach cancer cells showed the withdrawn and floating appearance that is typical in cellular impairment. In each test group more stomach cancer cells were killed than in the control group to a statistically significant degree. Each test group showed more suppression of viability of stomach cancer cells than that of the control group to a statistically significant degree. Analysis of the cell cycle showed that Duchesnea indica(Andr.) Focke inhibited division of stomach cancer cells. This experiment yielded empirical evidence for Duchesnea indica(Andr.) Focke as a statistically significant anticarcinogen, specifically against stomach cancer.

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Treatment of BG-1 Ovarian Cancer Cells Expressing Estrogen Receptors with Lambda-cyhalothrin and Cypermethrin Caused a Partial Estrogenicity Via an Estrogen Receptor-dependent Pathway

  • Kim, Cho-Won;Go, Ryeo-Eun;Choi, Kyung-Chul
    • Toxicological Research
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    • v.31 no.4
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    • pp.331-337
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    • 2015
  • Synthetic pyrethroids (SPs) are the most common pesticides which are recently used for indoor pest control. The widespread use of SPs has resulted in the increased exposure to wild animals and humans. Recently, some SPs are suspected as endocrine disrupting chemicals (EDCs) and have been assessed for their potential estrogenicity by adopting various analyzing assays. In this study, we examined the estrogenic effects of lambda-cyhalothrin (LC) and cypermethrin (CP), the most commonly used pesticides in Korea, using BG-1 ovarian cancer cells expressing estrogen receptors (ERs). To evaluate the estrogenic activities of two SPs, LC and CP, we employed MTT assay and reverse-transcription polymerase chain reaction (RT-PCR) in LC or CP treated BG-1 ovarian cancer cells. In MTT assay, LC ($10^{-6}M$) and CP ($10^{-5}M$) significantly induced the growth of BG-1 cancer cells. LC or CP-induced cell growth was antagonized by addition of ICI 182,720 ($10^{-8}M$), an ER antagonist, suggesting that this effect appears to be mediated by an ER-dependent manner. Moreover, RT-PCR results showed that transcriptional level of cyclin D1, a cell cycle-regulating gene, was significantly up-regulated by LC and CP, while these effects were reversed by co-treatment of ICI 182,780. However, p21, a cyclin D-ckd-4 inhibitor gene, was not altered by LC or CP. Moreover, $ER{\alpha}$ expression was not significantly changed by LC and CP, while down-regulated by E2. Finally, in xenografted mouse model transplanted with human BG-1 ovarian cancer cells, E2 significantly increased the tumor volume compare to a negative control, but LC did not. Taken together, these results suggest that LC and CP may possess estrogenic potentials by stimulating the growth of BG-1 ovarian cancer cells via partially ER signaling pathway associated with cell cycle as did E2, but this estrogenic effect was not found in in vivo mouse model.

Characterization of the Rosellinia necatrix Transcriptome and Genes Related to Pathogenesis by Single-Molecule mRNA Sequencing

  • Kim, Hyeongmin;Lee, Seung Jae;Jo, Ick-Hyun;Lee, Jinsu;Bae, Wonsil;Kim, Hyemin;Won, Kyungho;Hyun, Tae Kyung;Ryu, Hojin
    • The Plant Pathology Journal
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    • v.33 no.4
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    • pp.362-369
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    • 2017
  • White root rot disease, caused by the pathogen Rosellinia necatrix, is one of the world's most devastating plant fungal diseases and affects several commercially important species of fruit trees and crops. Recent global outbreaks of R. necatrix and advances in molecular techniques have both increased interest in this pathogen. However, the lack of information regarding the genomic structure and transcriptome of R. necatrix has been a barrier to the progress of functional genomic research and the control of this harmful pathogen. Here, we identified 10,616 novel full-length transcripts from the filamentous hyphal tissue of R. necatrix (KACC 40445 strain) using PacBio single-molecule sequencing technology. After annotation of the unigene sets, we selected 14 cell cycle-related genes, which are likely either positively or negatively involved in hyphal growth by cell cycle control. The expression of the selected genes was further compared between two strains that displayed different growth rates on nutritional media. Furthermore, we predicted pathogen-related effector genes and cell wall-degrading enzymes from the annotated gene sets. These results provide the most comprehensive transcriptomal resources for R. necatrix, and could facilitate functional genomics and further analyses of this important phytopathogen.