• Title/Summary/Keyword: ${\alpha}-Factor$

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A Study on Truss Model Incorporated with Internal Force State Factor for Shear Failure Mechanism in slender RC Beam (내력상태계수 개념을 도입한 철근콘크리트 보의 전단파괴 트러스모델에 관한 연구)

  • Cheong, Jae-Pyong;Kim, Woo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.609-614
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    • 2001
  • This paper is to explain reasonable shear behavior that can apply usually to reinforced concrete beams on the basic concepts of existent analysis and experimental research information. This study is succession $paper^{2) 3) 4) 5)}$ of treatise announced in existing and main control variable of reinforced concrete beams with stirrups used internal force state factor($\alpha$). Shear failure of reinforced concrete beams with stirrups is Influenced greatly because of the actual geometrical shape(a/d) of the concrete and flexural reinforcement steel ratio, stirrup reinforcement ratio and concrete compression strength, size effect etc. Therefore, shear behavior of reinforced concrete beams with stirrups that flexural crack is happened can be explained easily through proper extent proposal of internal force state factor($\alpha$) that express internal force state flowing. Use existent variable truss model by analysis model to explain arch action. Also, wish to compose each failure factors and correlation with internal force state factor by function, and when diagonal cracks happens, internal force state factor($\alpha$) study whether shear stress and some effect are.

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Role of PI3-Kinase/Akt Pathway in the Activation of Etoposide-Induced $NF-{\kappa}B$ Transcription Factor

  • Choi Yong-Seok;Park Heon-Yong;Jeong Sun-Joo
    • Journal of Microbiology and Biotechnology
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    • v.16 no.3
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    • pp.391-398
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    • 2006
  • $NF-{\kappa}B$ is a transcription factor involved in the innate immunity against bacterial infection and inflammation. It is also known to render cells resistant to the apoptosis caused by some anticancer drugs. Such a chemoresistance of cancer cells may be related to the activation of $NF-{\kappa}B$ transcription factor; however, the mechanism of activation is not well understood. Here, we demonstrate that a chemotherapeutic agent, etoposide, independently stimulates the $I{\kappa}B{\alpha}$ degradation pathway and PI3-kinase/Akt signaling pathway: The classical $I{\kappa}B{\alpha}$ degradation pathway leads to the nuclear translocation and DNA binding of p65 subunit through $IKK{\beta}$ kinase, whereas the PI3-kinase/Akt pathway plays a distinct role in activating this transcription factor. The PI3-kinase/Akt pathway acts on the p50 subunit of the $NF-{\kappa}B$ transcription factor and enhances the DNA binding affinity of the p50 protein. It may also explain the role of the PI3-kinase/Akt pathway in the anti-apoptotic function of $NF-{\kappa}B$ during chemoresistance of cancer cells.

A Case Study of the Commom Cause Failure Analysis of Digital Reactor Protection System (디지털 원자로 보호시스템의 공통원인고장 분석에 관한 사례연구)

  • Kong, Myung-Bock;Lee, Sang-Yong
    • IE interfaces
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    • v.25 no.4
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    • pp.382-392
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    • 2012
  • Reactor protection system to keep nuclear safety and operational economy of plants requires high reliability. Such a high reliability of the system can be achieved through the redundant design of components. However, common cause failures of components reduce the benefits of redundant design. Thus, the common cause failure analysis, to accurately calculate the reliability of the reactor protection system, is carried out using alpha-factor model. Analysis results to 24 operating months are that 1) the system reliability satisfies the reliability goal of EPRI-URD and 2) the common cause failure contributes 90% of the system unreliability. The uncertainty analysis using alpha factor parameters of 0.05 and 0.95 quantile values shows significantly large difference in the system unreliability.

Chromatographic Separation of Some Phenol Derivatives Using $\alpha$-Cyclodextrin in Mobile Phase ($\alpha$-씨클로덱스트린을 이동상으로 사용한 몇 가지 페놀 유도체들의 크로마토그래피적 분리)

  • 문영자;김봉희
    • Environmental Analysis Health and Toxicology
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    • v.12 no.3_4
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    • pp.75-84
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    • 1997
  • Chromatographic retention behavior and separation of various phenol derivatives on a Partisil 10 ODS 3 column-with mobile phase containing $\alpha$-cyclodextrin-were systematically studied. The decrease in k' values caused by the addition of cyclodextrins in the mobile phase was based on the formation of an inclusion complex, resulting in weakening of the hydrophobic interaction between solutes and the stationary phase. The content of the organic solvent in the mobile phase also influenced k' values of the solutes, and k' values increased with a decrease of the content of organic solvent in the mobile phase. A simple equation has been derived that reveals the hyperbolic dependence of the capacity factor on the total concentration of cyclodextrin. A plot of the reciprocal of the capacity factor against (CD)$_T$ gives a straight line and the dissociation constant, K$_D$, of the inclusion complex can be calculated from the slope. The capacity factor decreased with increasing temperature. The enthalpy was calculated from the slope of van't Hoff plots. Under optimum conditions, some mixtures of phenol derivatives were able to separated successfully.

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Serum interleukin-1beta and tumor necrosis factor-alpha in febrile seizures: is there a link?

  • Mahyar, Abolfazl;Ayazi, Parviz;Orangpour, Reza;Daneshi-Kohan, Mohammad Mahdi;Sarokhani, Mohammad Reza;Javadi, Amir;Habibi, Morteza;Talebi-Bakhshayesh, Mousa
    • Clinical and Experimental Pediatrics
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    • v.57 no.10
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    • pp.440-444
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    • 2014
  • Purpose: Febrile seizures are induced by fever and are the most common type of seizures in children. Although numerous studies have been performed on febrile seizures, their pathophysiology remains unclear. Recent studies have shown that cytokines may play a role in the pathogenesis of febrile seizures. The present study was conducted to identify potential links between serum interleukin-1beta (IL-$1{\beta}$), tumor necrosis factor-alpha (TNF-${\alpha}$), and febrile seizures. Methods: Ninety-two patients with simple or complex febrile seizures (46 patients per seizure type), and 46 controls with comparable age, sex, and severity of temperature were enrolled. Results: The median concentrations of serum IL-$1{\beta}$ in the simple, complex febrile seizure, and control groups were 0.05, 0.1, and 0.67 pg/mL, respectively (P=0.001). Moreover, the median concentrations of TNF-${\alpha}$ in the simple, complex febrile seizure, and control groups were 2.5, 1, and 61.5 pg/mL, respectively (P=0.001). Furthermore, there were significant differences between the case groups in serum IL-$1{\beta}$ and TNF-${\alpha}$ levels (P<0.05). Conclusion: Unlike previous studies, our study does not support the hypothesis that increased IL-$1{\beta}$ and TNF-${\alpha}$ production is involved in the pathogenesis of febrile seizures.

Gram-negative Septicemia after Infliximab Treatment in an Infant with Refractory Kawasaki Disease (불응성 가와사키병 환아에서 infliximab 사용 후 발생한 패혈증)

  • Lee, Jin Hwan;Yoon, Jung Min;Lim, Jae Woo;Ko, Kyong Og;Cheon, Eun Jung
    • Pediatric Infection and Vaccine
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    • v.21 no.3
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    • pp.225-230
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    • 2014
  • Kawasaki disease (KD) is an immune-mediated disease which is a leading cause of acquired cardiovascular disease in developed country. Recently, tumor necrosis factor-alpha (TNF-alpha) blocker, infliximab has been considered a promising option for patients with refractory KD. Although chronic use of a TNF-alpha blocker could increase risk of opportunistic infections, a few studies have documented that use of infliximab was safe without serious adverse effects in patients with KD. We observed serious bacterial infection after infliximab treatment in an infant with refractory KD. Our patient was a 5-month-old male infant diagnosed with KD who did not respond to repeated doses of intravenous immunoglobulin. We effectively treated him with a single infusion of infliximab (5 mg/kg), but gram-negative (Acinetobacter lwoffii) septicemia developed after infliximab infusion. Therefore, we report a case of serious septicemia after treatment with infliximab, and suggest considering the risk of severe infection when deciding whether to prescribe infliximab to an infant with refractory KD.

Hypoxia Induced Multidrug Resistance of Laryngeal Cancer Cells via Hypoxia-inducible Factor-1α

  • Li, Da-Wei;Dong, Pin;Wang, Fei;Chen, Xin-Wei;Xu, Cheng-Zhi;Zhou, Liang
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.8
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    • pp.4853-4858
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    • 2013
  • Objectives: To investigate whether hypoxia has an effect on regulation of multidrug resistance (MDR) to chemotherapeutic drugs in laryngeal carcinoma cells and explore the role of hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$). Methods: Laryngeal cancer cells were cultured under normoxic and hypoxic conditions. The sensitivity of the cells to multiple drugs and levels of apoptosis induced by paclitaxel were determined by MTT assay and annexin-V/propidium iodide staining analysis, respectively. HIF-$1{\alpha}$ expression was blocked by RNA interference. The expression of HIF-$1{\alpha}$ gene was detected by real-time quantitative RT-PCR and Western blotting. The value of fluorescence intensity of intracellular adriamycin accumulation and retention in cells was evaluated by flow cytometry. Results: The sensitivity to multiple chemotherapy agents and induction of apoptosis by paclitaxel could be reduced by hypoxia (P<0.05). A the same time, the adriamycin releasing index of cells was increased (P<0.05). However, resistance acquisition subject to hypoxia in vitro was suppressed by down-regulating HIF-$1{\alpha}$ expression. Conclusion: HIF-$1{\alpha}$ could be considered as a key regulator for mediating hypoxia-induced MDR in laryngeal cancer cells via inhibition of drug-induced apoptosis and decrease in intracellular drug accumulation.

Changes of Plasma Tumor Necrosis Factor α and C-Reactive Protein Levels in Patients with Hypertension Accompanied by Impaired Glucose Tolerance and their Clinical Significance

  • Xiao, Qiang;Wang, Lan-Ping;Ran, Zhang-Shen;Zhang, Xin-Huan
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.8
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    • pp.3389-3393
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    • 2015
  • Background: Chronic inflammation could affect the occurrence and development of malignant tumors. To explore the levels of tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$) and C-reactive protein (CRP) in patients accompanied by impaired glucose tolerance (IGT) and their clinical significance. Materials and Methods: A total of 210 patients hospitalized in Affiliated Hospital of Taishan Medical University from Jun., 2013 to Dec., 2014 were selected, in which 92 cases were accompanied by IGT. Meanwhile, 80 randomly-selected healthy people by physical examination were as the control. The levels of routine biochemical indexes, plasma TNF-${\alpha}$ and CRP in all subjects were measured. Results: Both systolic and diastolic pressures in hypertension group and hypertension plus IGT group were significantly higher than in control group (p<0.01), but there was no statistical significance between these two groups (p>0.05). The levels of fasting plasma glucose (FPG) and blood glucose 2 h after taking glucose in hypertension plus IGT group were markedly higher than other groups (p<0.01). Homeostasis model assessment-insulin resistance (HOMA-IR), TNF-${\alpha}$ and CRP contents were on the progressive increase in control, hypertension and hypertension plus IGT groups, but significant differences were presented among each group (P<0.01). Hypertension accompanied by IGT had a significantly-positive association with CRP, TNF-${\alpha}$, FPG and blood glucose 2h after taking glucose. Conclusions: The levels of plasma TNF-${\alpha}$ and CPR in patients with hypertension accompanied by IGT increase significantly, indicating that inflammatory reaction in these patient increases, thus suggesting that these patients should be focused regarding cancer prevention.

On Possible Application of Microorganism for Chemical Pulping (화학(化學)펄프 제조(製造)에 미생물(微生物)의 응용(應用) 가능성(可能性))

  • Lee, Seon-Ho;Yoon, Byong-Ho;Lee, Won-Yong
    • Journal of Forest and Environmental Science
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    • v.13 no.1
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    • pp.143-152
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    • 1997
  • The decayed wood by Fomes pini (Thore) Lloyd required a smaller H factor than the sound wood for pulping to permanganate number 20. The H factors for the decayed wood pulping by the kraft and soda processes were reduced by 15% and 17%, respectively, in the presence of 1% anthraquinone. The wood components degraded by fungi are normally more readily solubilized in alkali than the corresponding components in sound wood. The nonphenolic ${\beta}$-O-4 type lignin model compound, veratrylglycerol-${\beta}$-guaiacyl ether(I), and phenolic model compound, syringylglycerol-${\beta}$-syringyl ether(III), were degraded by the white-rot fungi to yield ${\alpha}$-guaiacoxy-${\beta}$-hydroxypropioveratrone(II) from the former and ${\alpha}$-syringyloxy-${\beta}$-hydroxypropiosyringone(IV) from the latter. Structures of the degradation products indicated that C ${\alpha}$-oxidation could occur with white-rot fungi. It has been shown that the alkaline cleavage of ${\beta}$-aryl ether bonds in the lignin units is accelerated by the presence of ${\alpha}$-carbonyl groups.

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Development of a Reporter System Monitoring Regulated Intramembrane Proteolysis of the Transmembrane bZIP Transcription Factor ATF6α

  • Kim, Jin-Ik;Kaufman, Randal J.;Back, Sung Hoon;Moon, Ja-Young
    • Molecules and Cells
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    • v.42 no.11
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    • pp.783-793
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    • 2019
  • When endoplasmic reticulum (ER) functions are perturbed, the ER induces several signaling pathways called unfolded protein response to reestablish ER homeostasis through three ER transmembrane proteins: inositol-requiring enzyme 1 (IRE1), PKR-like ER kinase (PERK), and activating transcription factor 6 (ATF6). Although it is important to measure the activity of ATF6 that can indicate the status of the ER, no specific cell-based reporter assay is currently available. Here, we report a new cell-based method for monitoring ER stress based on the cleavage of $ATF6{\alpha}$ by sequential actions of proteases at the Golgi apparatus during ER stress. A new expressing vector was constructed by using fusion gene of GAL4 DNA binding domain (GAL4DBD) and activation domain derived from herpes simplex virus VP16 protein (VP16AD) followed by a human $ATF6{\alpha}$ N-terminal deletion variant. During ER stress, the GAL4DBD-VP16AD(GV)-$hATF6{\alpha}$ deletion variant was cleaved to liberate active transcription activator encompassing GV-$hATF6{\alpha}$ fragment which could translocate into the nucleus. The translocated GV-$hATF6{\alpha}$ fragment strongly induced the expression of firefly luciferase in HeLa Luciferase Reporter cell line containing a stably integrated 5X GAL4 site-luciferase gene. The established double stable reporter cell line HLR-GV-$hATF6{\alpha}$(333) represents an innovative tool to investigate regulated intramembrane proteolysis of $ATF6{\alpha}$. It can substitute active pATF6(N) binding motif-based reporter cell lines.