• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.186-186
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• 1994

Many agonists have been known to activate the hydrolysis of membrane phospholipids through the bindings with corresponding receptors on the various cells. Diacylglycerol and inositol 1,4,5-trisphosphate(IP3) generated by the action of phosphoinositide-specific phospholipase C (PI-PLC) are well known second messengers for the activation of protein kinase C and the mobilization of Ca2+ in many cells. Three types of PI-PLC isozyme (${\alpha}$,${\gamma}$, and $\delta$) and several subtrpes for each type have been identified from mammalian sources by purification of enzymes and cloning of their cDNAs. Each type PI-PLC isozyme is coupled to different receptors and mediators, for example, ${\beta}$-types are coupled to the seven-transmembrane-receptors via Gq family of G-proteins and ${\beta}$-types directly to the receptor tyrosine kinases. Specific modulators for the signaling pathway through each type of PI-PLC should be very useful as potential potential candidates for lend substances in developing novel drugs. To establish the sensitive and convenient screening systems for searching modulators on PI-PLC mediated signaling, two kinds of approaches have been tried. (1) Establishment of in vitro assay condition for each type of PI-PLC isozyme: Overexpression by using vaccinia virus and purification of each isozyme was carried out for the preparation of large amounts of enaymes. Optimum and sensitive assay condition for the measurements of PI-ELC activities were established. (2) Development of the cell lines in which each type of PI-PLC is permanently overexpressed: A fibroblast cell line (3T3${\gamma}$1-7) in which PI-PLC-${\gamma}$1 was overexpressed by using pZip-neo expression vector was developed and used for the measurement of PDGF-induced IP3 formation. The responses for IP3 formed in 3T3${\gamma}$1-7 cells by the treatment of PDGF is 8 times more sensitive than those in control cells. 3T3${\gamma}$l-7 cell is useful for the screening of the inhibitors on the PDGF-induced cellular responses from large number of samples in a small volume(50 ${\mu}$l) and short time(5-15 min). Using these systems, we screened hundreds of herb-extracts for the inhibition of PDGF-induced IP3 formation and selected several extracts that showed the inhibition as the candidates for isolation and characterization of active substances. The determination of the acting point of selected extracts or fractions in the PDGF signaling pathway has been analyzing.

• 한국통신학회논문지
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• 제31권4B호
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• pp.291-302
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• 2006

최근 들어 휴대형 무선 기기들의 보급이 확대되고 WiBro/WiMAX/HSDPA 등의 고속 무선 데이터 통신 시스템의 등장에 따라 무선 환경에서 인터넷을 효과적으로 사용할 수 있는 이동성 관리 프로토콜에 대한 관심이 증가하고 있다. MIPv6(mobile IPv6)는 IPv6 환경에서 이동성을 지원하기 위한 프로토콜로 제안되었고, 이동이 빈번한 셀룰라 환경에서 효율적인 이동성 지원을 위해서 MIPv6의 핸드오버 성능을 개선한 HMIPv6(hierarchical MIPv6)와 FMIPv6(fast handovers for MIPv6) 등의 새로운 프로토콜에 대한 연구가 활발히 이루어지고 있다. 본 논문에서는 HMIPv6의 계층구조를 이용한 효율적 이동성 관리의 장점과 FMIPv6의 선행적 (proactive) 핸드오버 지원에 의한 끊임없는 서비스 지원의 장점을 효과적으로 결합하여 이동이 빈번한 셀룰러 환경에 적합한 새로운 이동성 관리 프로토콜인 HIMIPv6(highly integrated MIPv6)를 제안한다. HIMIPv6는 선행적 이동성 관리를 하위 도메인내의 핸드오버뿐만 아니라 하위 도메인간의 핸드오버에도 적용함으로써 시스템 전체적인 이동성 관리성능을 개선하였다. NS-2 시뮬레이션에 의한 성능 분석은 HIMIPv6가 빈번한 핸드오버 환경에서도 MIPv6, FMIPv6, 그리고 HMIPv6보다 이동성 지원에 필요한 신호 부하를 작게 발생시키고 핸드오버 상황에서의 서비스 끊김 현상이나 패킷 손실률도 작음을 보여준다.

• 대한구강악안면병리학회지
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• 제41권3호
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• pp.121-129
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• 2017

Coffee (Coffea spp.) is one of the most important agricultural commodities, being widely consumed in the world. Various beneficial health effects of coffee have been extensively investigated, but data on habitual coffee consumption and its bio-physiological effect have not been clearly explained as well as it is not proved the cause and effect between drinking coffee and its bio-physiological reactions. We made the dialyzed coffee extract (DCE), which is absorbable through gastrointestinal tract, in order to elucidate the cellular effect of whole small coffee molecules. RAW 264.7 cells, a murine macrophage lineage, were directly treated with DCE, i.e., DCE-2.5 (equivalent to 2.5 cups of coffee a day), DCE-5, and DCE-10, for 12 hours, and their protein extracts were examined by immunoprecipitation high performance liquid chromatography (IP-HPLC). RAW 264.7 cells differently expressed the inflammation-related proteins depending on the doses of DCE. RAW 264.7 cells treated with DCE showed marked increase of cathepsin C, cathepsin G, CD20, CD28, CD31, CD68, indicating the activation of innate immunity. Particularly, the macrophage biomarkers, cathepsin G, cathepsin C, CD31, and CD68 were markedly increased after DCE-5 and DCE-10 treatments, and the lymphocyte biomarkers, CD20 and CD28 were consistently increased and became marked after DCE-10 treatment. On the other hand, RAW 264.7 cells treated with DCE showed consistent increase of IL-10, an anti-inflammatory factor, but gradual decreases of different pro-inflammatory proteins including $TNF{\alpha}$, COX-2, lysozyme, MMP-2, and MMP-3. In particular, the cellular signaling of inflammation was gradually mitigated by the reduction of $TNF{\alpha}$, COX-2, IL-12, and M-CSF, and also the matrix inflammatory reaction was reduced by marked deceases of MMP-2, MMP-3, and lysozyme. These anti-inflammatory expressions were consistently found until DCE-10 treatment. Therefore, it is presumed that DCE may have dynamic effects of innate immunity activation and pro-inflammation suppression on RAW264.7 cells simultaneously. These effects were consistently found in the highest dose of coffee, DCE-10 (equivalent to 10 cups of coffee a day in man), that might imply the small coffee molecules were accumulated in RAW 264.7 cells after DCE-10 treatment and produce synergistic cytokine effects for innate immunity activation and anti-inflammatory reaction concurrently.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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• pp.201-205
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• 2007

본 논문은 휴대폰의 무선 인터넷 플랫폼 어플리케이션을 통해 화재 및 가스누출 등 각종 위험을 통보해 주는 지능형 홈서비스 로봇을 구현하였다. 지능형 홈서비스 로봇은 세 가지 구성요소(로봇부, 미들웨어부, 모바일부)로 이루어진다. 로봇부는 가스센서, 불꽃 감지센서, 연기 센서, 초음파 센서, 모터, 카메라, 블루투스 모듈로 구성되며, 각종 위급 상항을 감지한다. 미들웨어부는 미들웨어 어플리케이션을 통해 로봇부와 모바일부를 연결하고, 로봇을 모니터링하며 SMS모듈을 이용하여 응급상황을 통지한다. 모바일부는 TCP/IP 프로토콜을 이용하여 미들웨어부와 통신하며 로봇에 각종 명령을 내려주고 행동을 제어한다. 제안된 방식은 Atmega128 프로세서를 통하여 로봇부의 각종 센서를 제어하며, 모바일부는 WIPI 플랫폼 기반으로 개발하였다. 로봇부와 미들웨어부는 가정에 설치되며 외부에서 모바일부를 통하여 제어된다.

• 대한전자공학회논문지SD
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• 제46권12호
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• pp.30-35
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• 2009

본 논문에서는 3GPP (third generation partnership project) 릴리즈 7 고속 패킷 접속 에볼루션 규격에 포함된 기능 중 기지국 수용 능력 향상, 지연 시간 단축, 그리고 단말소비 전력 감소를 목적으로 새롭게 추가된 연속적인 패킷 연결 프로토콜의 유연한 설계 구조에 대한 것이다. 상기 프로토콜이 3GPP 고속 패킷 접속 규격 기준으로 새롭게 추가된 기능임에 착안하여, 기존 설계 및 검증된 고속 패킷 접속 플랫폼에서 최소한의 하드웨어 변경 및 추가만으로 상기 프로토콜이 구현되도록 고려하였다. 상기 제안된 연속적인 패킷 연결 프로토콜은 비연속적인 송/수신 모드 관련 신호 생성부와 기존 고속 패킷 접속 플랫폼과의 연동을 위한 인터페이스부로 구분된다. 마지막으로 제안된 연속적인 패킷 연결 프로토콜은 셀룰러 이동통신 분야에 적합하도록 규정화된 검증 단계에 따라 기존 고속 패킷 접속 FPGA 단말 모뎀 플랫폼 상에서 다양한 시나리오에 따라 검증되었다.

• 약학회지
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• 제59권4호
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• pp.158-163
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• 2015

Cardiac myocytes are subjected to fluid shear stress during each contraction and relaxation. Under pathological conditions, such as valve disease, heart failure or hypertension, shear stress in cardiac chamber increases due to high blood volume and pressure. The shear stress induces proarrhythmic longitudinal global $Ca^{2+}$ waves in atrial myocytes. In the present study, we further explored underlying cellular mechanism for the shear stress-induced longitudinal global $Ca^{2+}$ wave in isolated rat atrial myocytes. A shear stress of ${\sim}16dyn/cm^2$ was applied onto entire single myocyte using pressurized fluid puffing. Confocal $Ca^{2+}$ imaging was performed to measure local and global $Ca^{2+}$ signals. Shear stress elicited longitudinally propagating global $Ca^{2+}$ wave (${\sim}80{\mu}m/s$). The occurrence of shear stress-induced atrial $Ca^{2+}$ wave was eliminated by the inhibition of ryanodine receptors (RyRs) or inositol 1,4,5-trisphosphate receptors ($IP_3Rs$). In addition, pretreatment of phospholipase C (PLC) inhibitor U73122, but not its inactive analogue U73343, abolished the generation of longitudinal $Ca^{2+}$ wave under shear stress. Our data suggest that shear-induced longitudinal $Ca^{2+}$ wave may be induced by $Ca^{2+}$-induced $Ca^{2+}$ release through the RyRs which is triggered by $PLC-IP_3R$ signaling in atrial myocytes.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2006년도 춘계종합학술대회
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• pp.981-985
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• 2006

와이브로(Wibro)는 Wireless Broadband Internet의 줄임말로, 휴대 인터넷, 무선 광대역 인터넷, 무선초고속 인터넷으로 풀이됨. 언제(anytime), 어디서나(anywhere), 누구나(anyone), 어떤 장비(my device)로 이동하면서도 초고속으로 인터넷을 이용할 수 있는 서비스로, 이동전화와 무선 LAN의 중간영역에 위치하며, 와이브로 서비스는 기존 셀률러망과 다르게 IP망을 기반으로 서비스되기 때문에 단말기의 이동과 관계없이 끊임없이 연결을 유지하기 위해서는 핸드오버가 지원되어야 한다. 기존의 Micro Mobility 방식과 일반적인 Mobile IP 방식은 핸드오프시 지연속도와 패킷손실의 문제점을 가지고 있다. 이러한 문제점을 최소화 하기위해서 IETF라는 프로토콜이 제안되고, IETF의 Mip4, Mip6, Mipshop WG을 중심으로 표준화가 진행되고 있다. 본 논문에서는 와이브로 망에서의 문제점을 개선하여 단말기의 효율적인 핸드오버 지연을 최대한 줄이기 위한 기법과 활성화 및 전망에 대해 연구 분석 함.

• Biomolecules & Therapeutics
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• 제25권2호
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• pp.149-157
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• 2017

The interleukin-1 receptor antagonist (IL-1RA) is a potential stroke treatment candidate. Intranasal delivery is a novel method thereby a therapeutic protein can be penetrated into the brain parenchyma by bypassing the blood-brain barrier. Thus, this study tested whether intranasal IL-1RA can provide neuroprotection and brain penetration in transient cerebral ischemia. In male Sprague-Dawley rats, focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 1 h. The rats simultaneously received 50 mg/kg human IL-1RA through the intranasal (IN group) or intraperitoneal route (IP group). The other rats were given 0.5 mL/kg normal saline (EC group). Neurobehavioral function, infarct size, and the concentration of the administered human IL-1RA in the brain tissue were assessed. In addition, the cellular distribution of intranasal IL-1RA in the brain and its effect on proinflammatory cytokines expression were evaluated. Intranasal IL-1RA improved neurological deficit and reduced infarct size until 7 days after MCAO (p<0.05). The concentrations of the human IL-1RA in the brain tissue 24 h after MCAO were significantly greater in the IN group than in the IP group (p<0.05). The human IL-1RA was confirmed to be co-localized with neuron and microglia. Furthermore, the IN group had lower expression of $interleukin-1{\beta}$ and tumor necrosis $factor-{\alpha}$ at 6 h after MCAO than the EC group (p<0.05). These results suggest that intranasal IL-1RA can reach the brain parenchyma more efficiently and provide superior neuroprotection in the transient focal cerebral ischemia.

• The Korean Journal of Pain
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• 제34권2호
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• pp.185-192
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• 2021

Background: It is known that some analgesics as well as pain can affect the immune system. The aim of this study was to investigate the analgesic effect and immunomodulation of pregabalin (PGB) in a mouse incisional pain model. Methods: A postoperative pain model was induced by hind paw plantar incision in male BALB/c mice. Mice were randomly divided into four groups (n = 8): a saline-treated incision (incision), PGB-treated incision (PGB-incision), sham controls without incision or drug treatment (control), and a PGB-treated control (PGB-control). In the PGB treated groups, PGB was administered intraperitoneally (IP) 30 minutes before and 1 hour after the plantar incision. Changes of the mechanical nociceptive thresholds following incision were investigated. Mice were euthanized for spleen harvesting 12 hours after the plantar incision, and natural killer (NK) cytotoxicity to YAC 1 cells and lymphocyte proliferation responses to phytohemagglutinin were compared among these four groups. Results: Mechanical nociceptive thresholds were decreased after plantar incision and IP PGB administration recovered these decreased mechanical nociceptive thresholds (P < 0.001). NK activity was increased by foot incision, but NK activity in the PGB-incision group was significantly lower than that in the Incision group (P < 0.001). Incisional pain increased splenic lymphocyte proliferation, but PGB did not alter this response. Conclusions: Incisional pain alters cell immunity of the spleen in BALB/c mice. PGB showed antinocieptive effect on mouse incisional pain and attenuates the activation of NK cells in this painful condition. These results suggest that PGB treatment prevents increases in pain induced NK cell activity.

• Molecules and Cells
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• 제44권9호
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• pp.627-636
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• 2021

The three-dimensional organization of chromatin and its time-dependent changes greatly affect virtually every cellular function, especially DNA replication, genome maintenance, transcription regulation, and cell differentiation. Sequencing-based techniques such as ChIP-seq, ATAC-seq, and Hi-C provide abundant information on how genomic elements are coupled with regulatory proteins and functionally organized into hierarchical domains through their interactions. However, visualizing the time-dependent changes of such organization in individual cells remains challenging. Recent developments of CRISPR systems for site-specific fluorescent labeling of genomic loci have provided promising strategies for visualizing chromatin dynamics in live cells. However, there are several limiting factors, including background signals, off-target binding of CRISPR, and rapid photobleaching of the fluorophores, requiring a large number of target-bound CRISPR complexes to reliably distinguish the target-specific foci from the background. Various modifications have been engineered into the CRISPR system to enhance the signal-to-background ratio and signal longevity to detect target foci more reliably and efficiently, and to reduce the required target size. In this review, we comprehensively compare the performances of recently developed CRISPR designs for improved visualization of genomic loci in terms of the reliability of target detection, the ability to detect small repeat loci, and the allowed time of live tracking. Longer observation of genomic loci allows the detailed identification of the dynamic characteristics of chromatin. The diffusion properties of chromatin found in recent studies are reviewed, which provide suggestions for the underlying biological processes.