• Title/Summary/Keyword: switch cell

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Overview of Transforming Growth Factor β Superfamily Involvement in Glioblastoma Initiation and Progression

  • Nana, Andre Wendindonde;Yang, Pei-Ming;Lin, Hung-Yun
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.16
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    • pp.6813-6823
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    • 2015
  • Glioblastoma, also known as glioblastoma multiforme (GBM), is the most aggressive of human brain tumors and has a stunning progression with a mean survival of one year from the date of diagnosis. High cell proliferation, angiogenesis and/or necrosis are histopathological features of this cancer, which has no efficient curative therapy. This aggressiveness is associated with particular heterogeneity of the tumor featuring multiple genetic and epigenetic alterations, but also with implications of aberrant signaling driven by growth factors. The transforming growth factor ${\beta}$ ($TGF{\beta}$) superfamily is a large group of structurally related proteins including $TGF{\beta}$ subfamily members Nodal, Activin, Lefty, bone morphogenetic proteins (BMPs) and growth and differentiation factor (GDF). It is involved in important biological functions including morphogenesis, embryonic development, adult stem cell differentiation, immune regulation, wound healing and inflammation. This superfamily is also considered to impact on cancer biology including that of GBM, with various effects depending on the member. The $TGF{\beta}$ subfamily, in particular, is overexpressed in some GBM types which exhibit aggressive phenotypes. This subfamily impairs anti-cancer immune responses in several ways, including immune cells inhibition and major histocompatibility (MHC) class I and II abolishment. It promotes GBM angiogenesis by inducing angiogenic factors such as vascular endothelial growth factor (VEGF), plasminogen activator inhibitor (PAI-I) and insulinlike growth factor-binding protein 7 (IGFBP7), contributes to GBM progression by inducing metalloproteinases (MMPs), "pro-neoplastic" integrins (${\alpha}v{\beta}3$, ${\alpha}5{\beta}1$) and GBM initiating cells (GICs) as well as inducing a GBM mesenchymal phenotype. Equally, Nodal promotes GICs, induces cancer metabolic switch and supports GBM cell proliferation, but is negatively regulated by Lefty. Activin promotes GBM cell proliferation while GDF yields immune-escape function. On the other hand, BMPs target GICS and induce differentiation and sensitivity to chemotherapy. This multifaceted involvement of this superfamily in GBM necessitates different strategies in anti-cancer therapy. While suppressing the $TGF{\beta}$ subfamily yields advantageous results, enhancing BMPs production is also beneficial.

A Study on Predictive Traffic Control Algorithms for ABR Services (ABR 서비스를 위한 트래픽 예측 제어 알고리즘 연구)

  • 오창윤;장봉석
    • Journal of Internet Computing and Services
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    • v.1 no.2
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    • pp.29-37
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    • 2000
  • Asynchronous transfer mode is flexible to support multimedia communication services using asynchronous time-sharing and statistical multimedia techniques to the existing data communication area, ATM ABR service controls network traffic using feedback information on the network congestion situation in order to guarantee the demanded service qualities and the available cell rates, In this paper we apply the control method using queue length prediction to the formation of feedback information for more efficient ABR traffic control. If backward node receive the longer delayed feedback information on the impending congestion, the switch can be already congested from the uncontrolled arriving traffic and the fluctuation of queue length can be inefficiently high in the continuing time intervals, The feedback control method proposed in this paper predicts the queue length in the switch using the slope of queue length prediction function and queue length changes in time-series, The predicted congestion information is backward to the node, NLMS and neural network are used as the predictive control functions, and they are compared from performance on the queue length prediction. Simulation results show the efficiency of the proposed method compared to the feedback control method without the prediction, Therefore, we conclude that the efficient congestion and stability of the queue length controls are possible using the prediction scheme that can resolve the problems caused from the longer delays of the feedback information.

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HMGB1 Switches Alkylating DNA Damage-Induced Apoptosis to Necrosis (HMGB1에 의한 alkylating DNA 손상에 의해 유도된 세포사멸의 세포괴사로의 전환)

  • Lee, Su-Yeon;Jeong, Eui-Kyong;Jeon, Hyun-Min;Ju, Min-Kyung;Kim, Cho-Hee;Park, Hye-Gyeong;Kang, Ho-Sung
    • Journal of Life Science
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    • v.21 no.7
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    • pp.953-960
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    • 2011
  • Necrosis is characterized by the cell membrane rupture and release of the cellular contents, including high-mobility group box 1 protein (HMGB1), into the extracellular microenvironment. HMGB1 acts as a transcriptional regulator in nuclei, but exerts a pro-inflammatory and tumor-promoting cytokine activity when released into the extracellular space. Its overexpression is associated with tumor progression and chemoresistance. Thus, HMGB1 acts as a clinically important molecule in tumor biology. In this study, we examined whether HMGB1 affects cell death induced by anti-cancer drugs. Here we show that HMGB1 prevented cisplatin (alkylating agent)-induced apoptosis and switched the cell fate to necrosis in MCF-7, MDA-MB231, and MDA-MB361 cells. Similar apoptosis-to-necrosis switch effects of HMGB1 were observed in cells treated with 4-HC, another alkylating agent. In contrast, HMGB1 did not exert any significant effects on docetaxel (DOC)-induced apoptosis in MCF-7 cells. We also show that cisplatin-induced apoptosis was switched to necrosis in MCF-7 multicellular tumor spheroids (MTS) that were cultured for 8 days and had necrotic cores, but DOC-induced apoptosis was prevented without the apoptosis-to-necrosis switch. Finally, the levels of RAGE, a receptor of HMGB1, were increased with extended culture of MTS. These findings demonstrate that HMGB1 switches alkylating agent-induced apoptosis to necrosis, suggesting that the strategy to prevent necrosis occurring as an undesirable action of alkylating agent-based chemotherapy should be delineated to improve the efficacy of chemotherapy for cancer.

Design of Low-Area and Low-Power 1-kbit EEPROM (저면적.저전력 1Kb EEPROM 설계)

  • Yu, Yi-Ning;Yang, Hui-Ling;Jin, Li-Yan;Jang, Ji-Hye;Ha, Pan-Bong;Kim, Young-Hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.4
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    • pp.913-920
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    • 2011
  • In this paper, a logic process based 1-kbit EEPROM IP for RFID tag chips of 900MHz is designed. The cell array of the designed 1-kbit EEPROM IP is arranged in a form of four blocks of 16 rows x 16 columns, that is in a two-dimensional arrangement of one-word EEPROM phantom cells. We can reduce the IP size by making four memory blocks share CG (control gate) and TG (tunnel gate) driver circuits. We propose a TG switch circuit to supply respective TG bias voltages according to operational modes and to keep voltages between devices within 5.5V in terms of reliability in order to share the TG driver circuit. Also, we can reduce the power consumption in the read mode by using a partial activation method to activate just one of four memory blocks. Furthermore, we can reduce the access time by making BL (bit line) switching times faster in the read mode from reduced number of cells connected to each column. We design and compare two 1-kbit EEPROM IPs, two blocks of 32 rows ${\times}$ 16 columns and four blocks of 16 rows ${\times}$ 16 columns, which use Tower's $0.18{\mu}m$ CMOS process. The four-block IP is smaller by 11.9% in the layout size and by 51% in the power consumption in the read mode than the two-block counterpart.

Design of an Energy Management System for On-Chip Solar Energy Harvesting (온칩 태양 에너지 하베스팅을 위한 에너지 관리 시스템 설계)

  • Jeon, Ji-Ho;Lee, Duck-Hwan;Park, Joon-Ho;Park, Jong-Tae;Yu, Chong-Gun
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.48 no.2
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    • pp.15-21
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    • 2011
  • In this paper, an energy management circuit for solar energy harvesting system is designed in $0.35{\mu}m$ CMOS technology. The solar energy management system consists of an ISC(Integrated Solar Cell), a voltage booster, and an MPPT(Maximum Power Point Tracker) control unit. The ISC generates an open circuit voltage of 0.5V and a short circuit current of $15{\mu}A$. The voltage booster provides the following circuit with a supply voltage about 1.5V. The MPPT control unit turns on the pMOS switch to provide the load with power while the ISC operates at MPP. The SEMU(Solar Energy Management Unit) area is $360{\mu}m{\times}490{\mu}m$ including pads. The ISC area is $500{\mu}m{\times}2000{\mu}m$. Experimental results show that the designed SEMU performs proper MPPT control for solar energy harvested from the ISC. The measured MPP voltage range is about 370mV∼420mV.

Eco-friendly Smart Outdoor Jacket Production and Usability Evaluation (환경 친화적 스마트 아웃도어 재킷제작 및 사용성 평가)

  • Lee, Jeong Ran
    • Journal of the Korean Society of Clothing and Textiles
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    • v.38 no.6
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    • pp.845-856
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    • 2014
  • This study focused on the production and usability evaluation of smart outdoor jackets that are designed to provide convenience to middle-aged people by embedding devices for lighting and location tracing. The results were as follows. 1. Jacket power supplier was a assembled system composed of battery, charger, controller and switch. A solar cell was attached on the upper arm, and a wire type EL on the center line of a raglan sleeve along with a GPS on the left sleeve with a transparent vinyl pocket. The total weight of the jacket embedded with devices was 385-520g. 2. Operation of function, activity, acceptability, safety, convenience for device use, appearance, practical maintenance were selected based on an analysis of evaluation criteria of previous smart wear research. Criteria were narrowed to three major categories of satisfaction, appearance and maintenance. 3. Use satisfaction criterion consisted of wearable device functionality and physical, psychological use convenience. The evaluation indicated actual functionality. EL functions were especially effective and necessary. Convenience of use showed that a smart jacket was thought to be safe and the size was moderate regardless of age and gender. Outer appearance was satisfactory and respondents praised the color. The practical maintenance evaluation indicated that there was no challenge in doing the laundry since the solar battery and GPS were detachable. The practical use of smart outdoor jackets confirmed by fabric that was washable and dried quickly.

A Return-to-zero DAC with Tri-state Switching Scheme for Multiple Nyquist Operations

  • Yun, Jaecheol;Jung, Yun-Hwan;Yoo, Taegeun;Hong, Yohan;Kim, Ju Eon;Yoon, Dong-Hyun;Lee, Sung-Min;Jo, Youngkwon;Kim, Yong Sin;Baek, Kwang-Hyun
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.17 no.3
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    • pp.378-386
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    • 2017
  • A return-to-zero (RZ) digital-to-analog converter (DAC) with a tri-state switching scheme is proposed in this paper. The proposed scheme provides a triple weight output for RZ operation by using a conventional differential current switch and simple pseudo-differential F/Fs. The RZ function is realized with only two additional transistors in each F/F cell, which results in a power dissipation increase of less than 5%. To verify the performance of the proposed method, a 10-bit RZ DAC is fabricated using standard 180-nm CMOS technology. Measured results show that the worst SFDR performances are 60 dBc and 55 dBc in the 1st and 2nd Nyquist bands, respectively, when operating at 650 MHz clock frequency. The total power consumption is 64 mW, and the active area occupies $0.25mm^2$.

The User Identification System using the ubiFloor (유비플로어를 이용한 사용자 인증 시스템)

  • Lee Seunghun;Yun Jaeseok;Ryu Jeha;Woo Woontack
    • Journal of KIISE:Software and Applications
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    • v.32 no.4
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    • pp.258-267
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    • 2005
  • We propose the ubiFloor system to track and recognize users in ubiquitous computing environments such as ubiHome. Conventional user identification systems require users to carry tag sensors or use camera-based sensors to be very susceptible to environmental noise. Though floor-type systems may relieve these problems, high cost of load cell and DAQ boards makes the systems expensive. We propose the transparent user identification system, ubiFloor, exploiting user's walking pattern to recognize the user with a set of simple ON/OFF switch sensors. The experimental results show that the proposed system can recognize the 10 enrolled users at the correct recognition rate of $90\%$ without users' awareness of the system.

3-Dimensional Finite Element Analysis for Collecting Structure of Combustible Metal Dust During Explosion (가연성 금속분진 폭발시 저장 및 포집용 구조물에 대한 3차원 유한요소 해석)

  • Jang, Chang-Bong;Yong, Jong-Won;Baek, Jong-Bae;Kwon, Hyuck-Myun;Ko, Jae-Wook
    • Journal of the Korean Institute of Gas
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    • v.15 no.5
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    • pp.19-24
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    • 2011
  • Due to the latest industrial flow comes mainly switch to high-tech industries, combustible metals as Al, Mg, Li, Zn more require to use for the aircraft, car, cell phones, electronics and others. As a result, Increasing the processing of combustible metals due to increase in amount of combustible metals giving rise dust explosions also. Most Explosions caused by combustible metal dust, occurred in air cleaning device of local exhaust ventilation to capture and store the combustible dust. Therefore, this study was conducted to present and analyze technically that deformation and rupture shape of air cleaning device structure by Finite Element Analysis(FEA) rather than a simple prediction, in case of explosion occurs in an air cleaning device.

DNA chip Analysis of Psoriatic Skin during the Oriental Remedy (DNA chip을 이용한 건선의 한방치료에 관한 유전체 연구)

  • Kim Byoung Soo;Lee Sang Keun;Kim Hyun Woong;Lee Jeung Hoon;Lim Jong Soon;Kang Jung Soo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.2
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    • pp.468-473
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    • 2004
  • Psoriasis is a chronic inflammatory disease of the skin characterized by epidermal hyperplasia, dermal angiogenesis, infiltration of activated T cells, and increased cytokine levels, and affects 1-3% of the world-wide population. Although many immunological and clinical reports indicate a role for the immune system in the pathogenesis of psoriasis, puzzling questions about psoriasis remain unsolved. During the several decade, immunosuppressor and PUVA treatment are ubiquitously used to psoriasis therapy. But recently, to promote terminal differentiation of keratinocytes, block either NK-Tcell or T-cell activation, and interrupting the angiogenic switch represent another therapeutic opportunity in psoriasis. To keep face with immunological therapy, the needs of newly designed prescription on the psoriasis treatments were demanded. With the object of understand the psoriasis from an orient medical point of view, patients were administrated the GY during several weeks. We investigated the changes of gene expression in involved and uninvolved skin samples during the oriental remedy. Microarray data showed several important results. First, Gene expression profiling is similar to each patient. Second, precursor proteins that organize cornified envelops are decreased at the end of remedy. But genes which related to apoptosis, G-protein signalling, and lipid metabolism are increased. Third, 68.5% of clustering genes localized on the psoriasis susceptibility locus. In our results indicated that GY influence on the keratinocytes hyperproliferation by regulating the gene, which located on the psoriasis susceptibility locus.