• Title/Summary/Keyword: knock down

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Swiprosin-1 Regulates Cytokine Expression of Human Mast Cell Line HMC-1 through Actin Remodeling

  • Ramesh, T.P.;Kim, Young-Dae;Kwon, Min-Sung;Jun, Chang-Duk;Kim, Sang-Wook
    • IMMUNE NETWORK
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    • v.9 no.6
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    • pp.274-284
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    • 2009
  • Background: Swiprosin-1 was identified in human CD8+ lymphocytes, mature B cells and non-lymphonoid tissue. We have recently reported that swiprosin-1 is expressed in mast cells and up-regulated in both in vitro and in vivo. Methods: The expression of cytokines and swiprosin-1 were determined by by real time PCR and conventional PCR. Pharmacological inhibitors were treated to investigate potential mechanism of swiprosin-1 in mast cell activation. Actin content was evaluated by confocal microscopy and flow cytometry. Results: The swiprosin-1 augmented PMA/A23187-induced expression of cytokines and release of histamine. However, knock-down of swiprosin-1 showed only a modest effect on PMA/A23187-induced cytokine expression, suggesting that swiprosin-1 has gain-of-function characteristics. Swiprosin-1 was found in microvilli-like membrane protrusions and highly co-localized with F-actin. Importantly, either disruption of actin by cytochalasin B or inhibition of PI3 kinase, an enzyme involved in actin remodeling, by wortmannin blocked cytokine expression only in swiprosin-1-overexpressing cells. Conclusion: These results suggest that swiprosin-1 modulates mast cell activation potentially through actin regulation.

Knockdown of a Proliferation-inducing Ligand (PRIL) Suppresses the Proliferation of Gastric Cancer Cells

  • Cui, Jiu-Wei;Li, Yan;Wang, Chang;Yao, Cheng;Li, Wei
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.2
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    • pp.633-636
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    • 2012
  • Purpose: PRIL (proliferation-inducing ligand) is a newly identified member of the tumor necrosis factor (TNF) family and modulates death ligand-induced apoptosis. Here, we investigated the effect of PRIL on cellular characteristics relating to tumor progression in human gastric cancer. Method: Recombinant lentivirus containing PRIL siRNA was constructed and then infected MGC803 and SGC7901 gastric cancer cells. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] colony formation and cell cycle analysis were used to study the effect of PRIL knockdown on gastric cancer cell proliferation. Results: PRIL expression in lentivirus infected cells was significantly reduced as evidenced by quantitative real-time PCR. Cell viability and colony formation of MGC803 and SGC7901 cells were significantly hampered in PRIL knock-down cells. Moreover, the cell cycle was arrested at G2/M phase, elucidating the mechanism underlying the inhibitory effect of siRNA on cell proliferation. Conclusions: Our study indicated that PRIL functions in promoting cell growth, and lentivirus-mediated PRIL gene knockdown might be a promising strategy in the treatment of gastric cancer.

Alteration of DNA Methylation in Oct-4 Gene in Mouse Preimplantation Embryos by the Interference RNA

  • Kim, Jong-Mu;Ko, Yeoung-Gyu;Seong, Hwan-Hoo;Chung, Hak-Jae;Chang, Won-Kyong;Kim, Nam-Hyung
    • Reproductive and Developmental Biology
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    • v.31 no.1
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    • pp.21-28
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    • 2007
  • During early embryo development, Oct-4 is an important transcription factor for the early differentiation the present study was first examined methylation status in distal enhancer and promoter region of Oct-4 during mouse pre-implantation embryo development. In oocyte and sperm, high methylation was observed in both distal and proximal of promoter in Oct-4. Following fertilization relatively high methylation level remained until 8-cell stage embryos, but decreased at the morula and blastocyst stage. Specific gene knock down of Oct-4 by siRNA injection into zygote induced higher methylation rates of both distal and proximal region of promoter of Oct-4. These results suggest a functional link between the DNA methylation status of distal and promoter resign in the Oct-4 gene and the gene sequence-specific transcriptional silencing by exogenous siRNA injection during mouse preimplantation embryos.

A Study on Development of BIM Library for Unit Modular Housing - Focused on Small-sized Urban-life-housing - (유닛모듈러 주택의 BIM 라이브러리 개발 연구 - 소규모 도시형 생활주택을 중심으로 -)

  • Lee, Chang-Jae;Lim, Seok-Ho
    • Journal of the Korean housing association
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    • v.23 no.6
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    • pp.11-20
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    • 2012
  • This Study developed library of parts, applied with 3-dimension character which has width, length and height and a reference plane, for the system development of BIM design on housing unit modular. The current BIM software has not the concept of a reference plane or work tolerance in modular, so the development of parts library applied to unit modular has not moved forward. So, we developed, in this study, parts library applied to windows, built-in-furniture, kitchen systems and knock down bathrooms, with a reference plane and work tolerance based on single roon prototype on urban-life-housings. BIM library can utilize changed size and work tolerance of parts, and fabricating reference plane will be created automatically when an engineer puts work tolerance in the BIM library with supplement of some category related to work reference. Through this BIM library development, we consider the part module can be used for housing complex planning, and architectural designers will be able to utilize the BIM library for housing complex design.

Roles of Neutral Sphingomyelinase 1 on CD95-Mediated Apoptosis in Human Jurkat T Lymphocytes

  • Lee, Hyun-Min;Surh, Bo-Young;Chun, Young-Jin
    • Biomolecules & Therapeutics
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    • v.18 no.3
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    • pp.262-270
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    • 2010
  • CD95 receptor is a member of tumor necrosis factor receptor family that mediates apoptosis in many cell types when bound by CD95 ligand or cross-linked by agonistic anti-CD95 antibodies. To determine the role of neutral sphingomyelinase (nSMase) on CD95-mediatd apoptosis, human Jurkat T lymphocytes were exposed to recombinant human CD95 ligand. Treatment with CD95 ligand induced cell death in a concentration and time-dependent manner. CD95-induced cell death was suppressed by inhibitors of SMase such as AY9944 or desipramine. Transfection with human nSMase1 siRNA plasmid into CD95 ligand-treated cells significantly prevented CD95-mediated cell death. CD95-mediated elevation of intracellular ceramide level detected by FACS analysis with anti-ceramide antibody was also decreased by nSMase1 siRNA. Knock-down of nSMase1 expression also blocked cytochrome c release into cytosol and caspase-3 cleavage in CD95-treated cells. Taken together, these results suggest that nSMase1 may play an important role in CD95-mediated apoptotic cell death in Jurkat T cells.

The effects of nutrient depleted microenvironments and delta-like 1 homologue (DLK1) on apoptosis in neuroblastoma

  • Kim, Yu-Ri
    • Nutrition Research and Practice
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    • v.4 no.6
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    • pp.455-461
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    • 2010
  • The tumor microenvironment, particularly sufficient nutrition and oxygen supply, is important for tumor cell survival. Nutrition deprivation causes cancer cell death. Since apoptosis is a major mechanism of neuronal loss, we explored neuronal apoptosis in various microenvironment conditions employing neuroblastoma (NB) cells. To investigate the effects of tumor malignancy and differentiation on apoptosis, the cells were exposed to poor microenvironments characterized as serum-free, low-glucose, and hypoxia. Incubation of the cells in serum-free and low-glucose environments significantly increased apoptosis in less malignant and more differentiated N-type IMR32 cells, whereas more malignant and less differentiated I-type BE(2)C cells were not affected by those treatments. In contrast, hypoxia (1 % $O_2$) did not affect apoptosis despite cell malignancy. It is suggested that DLK1 constitutes an important stem cell pathway for regulating self-renewal, clonogenicity, and tumorigenicity. This raises questions about the role of DLK1 in the cellular resistance of cancer cells under poor microenvironments, which cancer cells normally encounter. In the present study, DLK1 overexpression resulted in marked protection from apoptosis induced by nutrient deprivation. This in vitro model demonstrated that increasing severity of nutrition deprivation and knock-down of DLK1 caused greater apoptotic death, which could be a useful strategy for targeted therapies in fighting NB as well as for evaluating how nutrient deprived cells respond to therapeutic manipulation.

Inventing Computer Desk for Education by Group (단체 교육용 컴퓨터 책상 개발)

  • Kang, Myung-Sun;Lim, Kwang-Soon
    • Journal of the Korea Furniture Society
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    • v.19 no.3
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    • pp.193-202
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    • 2008
  • In order to occupy educational furniture market that grows by the day and to meet demands for alternative product for the current market, this study took business features and productivity of Sinil Furniture Co into consideration, and developed computer desk for education by group, which is new among educational furniture. The scope of the study ranges from data research based on design process into creation of prototype. By improving the condition where, despite that electrically-powered computer desk for anti-theft system is high priced, it sees frequent malfunction, the study suggested low-priced, non- electrically-powered anti-theft system which has more solid structure. Furthermore, in order for the user to be more free and comfortable while studying on it, it differentiates from other products by locating PC main body to the back of the monitor and lowering it below the altitude of monitor to prevent it from interfering with studies. We've made the higher board of the desk in a soft curved-shape in order to lessen the stress from studying. And as space for the monitor's lower mount was decreased, we've put the lower mount below the higher board; so that lacking space can be recovered while functioning as anti-theft system. Moreover, we've covered the PC main body with steel cover so that it would add color and formal luxuriousness to the appearance of the desk. Considering ease of mobility and productivity, knock-down system was introduced.

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Guild Structure and Seasonal Occurrences of Spider Communities in Pine Plantation Habitat (소나무숲의 거미군집의 Guild 구조 및 계절적 변동)

  • Lee, Goen-Hyoung;Lee, Hai-Poong
    • The Korean Journal of Ecology
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    • v.13 no.2
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    • pp.149-163
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    • 1990
  • Two distinct spider communities were studied in the crowns and ground surfaces of pine plantations at Mt. Ungilsan, Kyonggi-do using pitfall traps and knock-down by spraying of an insecticide (D.D.V.P.) to sample spiders. There were 34 species of 11 families in the ground community and 41 species of 15 families in the crown community, with only 9 species being collected in both. Wandering spiders comprised 78.5% of the crown community and 90.8% of the ground community. Guild abundance and the most abundant families were distinctly different in the two habitats: agile hunters (Salticidae:32.4%) and nocturnal hunters (Clubionidae:19%) in the crown, runners (Lycocidae:32.8%) and nocturnal hunters (Gnaphosidae:31.2%) in the ground. Dominant species were Clubiona jucunda (Karsch) and Mymarachne japonica (Karsch) in the crown, while in the ground they were Pardosa laura Karsch and Gnaphosa silvicola. Species diversity(H ) had peaks in May, July and November in the ground community, while in the crown community peaks were in June and September. The seasonal trends of species diversity (H ) were due mainly to differences in the number of species and the numbers of individuals collected at each sample date rather than to differences in equitability among species. Spier guilds and dominant species have different seasonal patterns based on the temporal differences in prey availability in the two communities and the reduction of temporal overlap.

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Identification and Characterization of Protein Arginine Methyltransferase 1 in Acanthamoeba castellanii

  • Moon, Eun-Kyung;Kong, Hyun-Hee;Hong, Yeonchul;Lee, Hae-Ahm;Quan, Fu-Shi
    • Parasites, Hosts and Diseases
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    • v.55 no.2
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    • pp.109-114
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    • 2017
  • Protein arginine methyltransferase (PRMT) is an important epigenetic regulator in eukaryotic cells. During encystation, an essential process for Acanthamoeba survival, the expression of a lot of genes involved in the encystation process has to be regulated in order to be induced or inhibited. However, the regulation mechanism of these genes is yet unknown. In this study, the full-length 1,059 bp cDNA sequence of Acanthamoeba castellanii PRMT1 (AcPRMT1) was cloned for the first time. The AcPRMT1 protein comprised of 352 amino acids with a SAM-dependent methyltransferase PRMT-type domain. The expression level of AcPRMT1 was highly increased during encystation of A. castellanii. The EGFP-AcPRMT1 fusion protein was distributed over the cytoplasm, but it was mainly localized in the nucleus of Acanthamoeba. Knock down of AcPRMT1 by synthetic siRNA with a complementary sequence failed to form mature cysts. These findings suggested that AcPRMT1 plays a critical role in the regulation of encystation of A. castellanii. The target gene of AcPRMT1 regulation and the detailed mechanisms need to be investigated by further studies.

A Study on Development of Modular System using Light-weighted Structure Members (경량형강을 사용한 모듈러 시스템 개발에 관한 연구)

  • Zheng, Sheng-Lin;Ju, Gi-Su;Park, Sung-Moo
    • Proceeding of KASS Symposium
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    • 2008.05a
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    • pp.43-48
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    • 2008
  • The object of this paper is to evaluate on constructability of modular steel frame with the hollow structural steel section to LEB C-shape. A modular building is built with factory-manufacture and site-construction. The advantage of a Modular building presents that enhanced building quality, shortened construction period and easy at an expansion and enlargement for buildings but also has demerits such as size restriction of the modular units according to the Road Traffic Law and Inflexibility of the unit composition. So in this study we use light-weighted structure members with bolted joint for easy Knock-down and traffic, also we evaluated the constructability of this bolted joints type modular buildings.

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