• 미생물학회지
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• 제49권4호
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• pp.301-308
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• 2013

Programmed Death-1 (PD-1)은 중요한 면역조절분자들 중 하나로 다양한 면역활성인자에 자극된 T 세포, B 세포, NKT 세포 및 대식세포에서 발현된다. Lipopolysaccaride (LPS)는 그람음성세균의 세포벽구성물질로 PD-1 발현을 유도하는 중요 면역원들 중 하나로 알려져 있다. 그러나 선천면역세포에서 PD-1 발현기전에 관한 연구는 미비한 실정이다. 본 연구에서는 LPS에 의해 자극된 Raw264.7 세포주를 대상으로 PD-1 발현 및 발현조전기전을 RT-PCR, Western Blot, 유세포분석기, ChIP assay 및 co-immunoprecipitation 방법으로 조사하였다. Raw264.7 세포주가 LPS로 자극되었을 때 PI3K 및 p38 신호전달경로를 경유하여 PD-1 발현이 크게 증가되었다. 또한 LPS 주사된 생쥐의 비장유래 대식세포에서도 PD-1 발현이 증가됨을 확인 하였다. PD-1 유전자의 프로모터 분석을 통해서 NF-${\kappa}B$ 및 IRF-1 결합부위가 PD-1 발현에 중요함을 알 수 있었다. 또한 PD-1 발현을 극대화하기 위하여 전사조절인자 NF-${\kappa}B$ 및 IRF-1의 공동활성이 필수적임을 확인하였다. 본 연구결과는 LPS 유도 생쥐패혈증모델에서 선천면역세포에 발현된 PD-1분자의 제어를 통한 질병 연구에 유용한 자료로 이용될 수 있을 것으로 사료된다.

• 대한한의학방제학회지
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• 제16권2호
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• pp.219-228
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• 2008

Objective : The present study was designed to investigate whether the water extract of the root of Scutellaria baicalensis could regulate lipopolysaccharide (LPS)-induced type 1 interferon. Methods : To evaluate of type 1 interferon inhibitory effect of the root of Scutellaria baicalensis, we examined type 1 interferon in LPS-stimulated RAW264.7 cells. Furthermore, Interleukin (IL)-10 and interferon regulatory factor (IRF) - 1, 7 expression level were examined to study the inhibition mechanisms. Results 1. Extract from the root of Scutellaria baicalensis didn't have any cytotoxity itelf. 2. Extract from the root of Scutellaria baicalensis inhibited interferon-a,b in dose dependant- and type 1 interferon production in time dependant manner. 3. Extract from the root of Scutellaria baicalensis reduced IL-10 and IRF-1, 7 production in LPS-stimulated RAW 264.7 cells. Conclusion : The extract from the root of Scutellaria baicalensis down-regulated LPS-induced type 1 interferon through suppression of IL-10 and IRF-1, 7 expression. This results suggested that the extract from the root of Scutellaria baicalensis may be a beneficial drug against inflammatory diseases.

• 융합신호처리학회논문지
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• 제11권2호
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• pp.163-168
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• 2010

본 논문에서는 전력용 반도체 소자를 위한 과열보호시스템의 설계 및 구현에 관한 내용을 다룬다. 제안된 시스템은 전력용 반도체 소자의 온도를 검출하기 위해서 별도의 온도센서나 트랜지스터를 사용하는 기존의 방법과 달리 파워 MOSFET의 $R_{ds(on)}$ 특성만을 이용한다. 과열보호를 위한 제안된 방법은 IRF840 파워 MOSFET를 이용하여 성공적으로 시험되었다. 제안된 과열보호 알고리즘을 구현하기 위해 PIC 마이크로컨트롤러인 PIC16F877A 소자를 사용하였다. 내장된 10-bit A/D 변환기는 IRF840의 소스와 드레인 전압변화를 검출하기 위해 이용된다. 측정된 소스-드레인 간 전압으로부터 도출된 온도-저항 간의 관계식은 파워 MOSFET의 게이트 트리거 신호를 제어한다. 만약 검출된 온도 전압의 임계값이 설정된 임의의 보호온도 전압 값을 초과할 때 마이크로컨트롤러는 파워 MOSFET으로부터 트리거 신호를 제거시켜 파워 MOSFET이 과열되는 것을 방지한다. 실험결과는 제안된 시스템이 정확도 측면에서 1.5%의 오차 이내로 정확함을 보여주었다.

• 동의생리병리학회지
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• 제23권5호
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• pp.986-992
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• 2009

Type I interferons (IFNs) are critical mediators of the innate immune system to defend viral infection. Interferon regulatory factor (IRF) and signal transducer and activator of transcription (STAT) play critical roles in type I IFN production in response to viral infection. Luteolin is natural polyphenolic compounds that have anti-inflammatory, cytoprotective and anti-carcinogenic effects. However, the mechanism of action and impact of luteolin on innate immunity is still unknown. In this study, we examined the effects of luteolin on the lipopolysacchride (LPS)-induced inflammatory responses. Luteolin inhibited Type I IFNs expression of mRNA and increased interleukin(IL)-10 expression of mRNA. Next, we examined the protective effects of IL-10 using IL-10 neutralizing antibody (IL-10NA). Blockade of IL-10 action didn't cause a significant reduction of Type I IFNs than LPS-induced luteolin pretreatment. Pretreatment of luteolin inhibited the level of IRF-1, and IRF-7 mRNA and the nuclear translocation of IRF-3. Also, luteolin reduced the activation of STAT - 1, 3. Theses results suggest that luteolin inhibits LPS-induced the production of Type I IFNS by both IRFs and STATs not IL-10 and may be a beneficial drug for the treatment of inflammatory disease.

• 대한원격탐사학회지
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• 제24권2호
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• pp.99-106
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• 2008

영상 레이다(SAR)는 주야간, 일조량에 관계없이 전천후로 영상획득이 가능하여 군사용으로는 물론 과학 민수용으로 광범위하게 활용된다. SAR 시스템에서는 고도, 운용 주파수, PRF 등의 다양한 시스템설계 파라미터로부터 생성된 임펄스 응답 함수(impulse response function)를 분석하여 공간해상도, PSLR, ISLR 등 영상품질 성능 파라미터의 추정이 가능하다. 그러나 모델링된 임펄스 응답 특성은 주변 클러터 환경이 고러되지 않은 이상적인 경우이므로 실제 주변 클러터 환경을 고려한 SAR 영상품질 분석 기법이 필요하다. 본 논문에서는 먼저 주요 SAR시스템 파라미터를 기반으로 SAR 점표적 원시 데이터를 생성하고, 거리-도플러 알고리듬(range-Doppler algorithm)을 이용하여 임펄스 응답 데이터를 형성한다. 그리고 실제 SAR영상의 일부분을 추출하여 주변 배경 클러터 환경 데이터를 형성한 후, 임펄스 응답 데이터를 삽입한다. 형성된 응답 데이터는 영상품질의 정확도를 향상시키고자 확장보간법을 도입하여 분석하고, 이에 대한 효과를 주요 도플러 파라미터인 방위 FM율 오차에 따른 성능분석을 수행함으로써 확인한다.

• Clinical and Experimental Reproductive Medicine
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• 제38권4호
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• pp.193-202
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• 2011

Objective: We found previously that $interferon$ $regulatory$ factor ($Irf$)-1 is a germinal vesicle (GV)-selective gene that highly expressed in GV as compared to metaphase II oocytes. To our knowledge, the function of $Irf-1$ in oocytes has yet to be examined. The present study was conducted to determine the relationship between retinoic acid (RA) and RA-mediated expression of $Irf-1$ and the mouse oocyte maturation. Methods: Immature cumulus-oocyte-complexes (COCs) were collected from 17-day-old female mice and cultured $in$ $vitro$ for 16 hours in the presence of varying concentrations of RA (0-10 ${\mu}M$). Rate of oocyte maturation and activation was measured. Gene expression was measured by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) and cytokine secretion in the medium was measured by Bio-Plex analysis. Apoptosis was analyzed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Results: The rates of oocyte maturation to metaphase II and oocyte activation increased significantly with RA treatment (10 nM-1 ${\mu}M$). With 100 nM RA treatment, lowest level of $Irf-1$ mRNA and cumulus cell's apoptosis was found. Among 23 cytokines measured by Bio-Plex system, the substantial changes in secretion of tumor necrosis factor-${\alpha}$, macrophage inflammatory protein-$1{\beta}$, eotaxin and interleukin-12 (p40) from COCs in response to RA were detected. Conclusion: We concluded that the maturation of oocytes and $Irf-1$ expression are negatively correlated, and RA enhances the developmental competence of mouse immature oocytes $in$ $vitro$ by suppressing apoptosis of cumulus cells. Using a mouse model, results of the present study provide insights into improved culture conditions for $in$ $vitro$ oocyte maturation and relevant cytokine production and secretion in assisted reproductive technology.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제36권4호
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• pp.487-509
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• 2022

본 연구는 고등학교 진학을 위한 입시라는 독특한 수학 교실 배경이 있는 중국 중학교 수학 교실에서 일어나는 교실 담화를 분석하는데 목적이 있다. 이를 위하여 본 연구에서는 수학 교실 담화를 시작 발화로서 교사 발문 통계와 교사 발문 유형별 에피소드를 분석하였고, 교실 담화 구조 분석으로는 특히 다섯 가지 IRF 하위 유형을 밝혀낼 수 있었다. 중국 귀주성 귀양시에 위치한 H학교에 재직 중인 세 명의 수학 교사가 녹화했던 수학 수업 총 15개의 녹취록과 교사 서면 인터뷰 내용을 중심으로 자료를 분석하였다. 본 연구 결과를 보면, 차시별로 평균 20개 교사 발문이 관찰되었고 교사 발문의 사회적 스케폴딩 역할이 있었으며, 교사 발문 유형은 확인형 발문(이해확인 발문, 설명요구 발문, 상세요구 발문, 재확인 발문)과 정보형 발문(정보제시 발문)으로 분류되었다. 그리고 교실 담화 분석에 따르면 IR형 담화 구조는 거의 관찰되지 않았으며, IRF형 담화 구조의 경우는 단편적인 평가, 평가 및 이유, 근거 설명, 평가 및 학생 반응 재진술, 다른 사고나 해법 안내, 그리고 학생 답 수정이나 교사 의견 제시로 구분되었다.

• Natural Product Sciences
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• 제28권3호
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• pp.121-129
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• 2022

Despite considerable efforts, cancer remains an aggressive killer worldwide. Chemotherapeutic drugs that are currently in use lead to destructive side effects and have not succeeded in fulfilling expectations. For centuries, medicinal plants are used for treating various diseases and are also known to have anticancer activity. The main aim of this research was to evaluate antiproliferative activity of saffron, clove, fenugreek, and green tea on Vero and MDA-MB-231 cell lines and to subsequently analyze the effect of these extracts on IRAK-4, TAK1, IKK-alpha, IKK-beta, NF-Kappa B, IRF3, IRF7 genes in Toll Like Receptors (TLRs) pathway. Antiproliferative assay was done by Neutral Red Dye uptake assay. Methanolic extract of green tea was found to be most effective against both cell lines as IC₅₀ was achieved at least concentration of the extract. For molecular studies, MDAMB-231 cells were sensitized with methanolic extract of green tea at same IC₅₀, and RT-PCR was performed to determine the relative expression of genes. Expression of IRAK-4, TAK1, IKK-beta, NF-Kappa B, IRF3 genes was down regulated and IRF7 and IKKalpha was upregulated. Green tea has a potential cytotoxic effect on both cell lines which was demonstrated by its effect on the expression of (TLRs) pathway genes.

• International Journal of Naval Architecture and Ocean Engineering
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• 제3권1호
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• pp.53-64
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• 2011

The present study considers multi-level approach for the analysis of parametric roll phenomena. Three kinds of computation method, GM variation, impulse response function (IRF), and Rankine panel method, are applied for the multi-level approach. IRF and Rankine panel method are based on the weakly nonlinear formulation which includes nonlinear Froude-Krylov and restoring forces. In the computation result of parametric roll occurrence test in regular waves, IRF and Rankine panel method show similar tendency. Although the GM variation approach predicts the occurrence of parametric roll at twice roll natural frequency, its frequency criteria shows a little difference. Nonlinear roll motion in bichromatic wave is also considered in this study. To prove the unstable roll motion in bichromatic waves, theoretical and numerical approaches are applied. The occurrence of parametric roll is theoretically examined by introducing the quasi-periodic Mathieu equation. Instability criteria are well predicted from stability analysis in theoretical approach. From the Fourier analysis, it has been verified that difference-frequency effects create the unstable roll motion. The occurrence of unstable roll motion in bichromatic wave is also observed in the experiment.

• Journal of Microbiology and Biotechnology
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• 제31권2호
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• pp.226-232
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• 2021

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging phlebovirus of the Phenuiviridae family that has been circulating in the following Asian countries: Vietnam, Myanmar, Taiwan, China, Japan, and South Korea. Despite the increasing infection rates and relatively high mortality rate, there is limited information available regarding SFTSV pathogenesis. In addition, there are currently no vaccines or effective antiviral treatments available. Previous reports have shown that SFTSV suppresses the host immune response and its nonstructural proteins (NSs) function as an antagonist of type I interferon (IFN), whose induction is an essential part of the host defense system against viral infections. Given that SFTSV NSs suppress the innate immune response by inhibiting type I IFN, we investigated the mechanism utilized by SFTSV NSs to evade IFNmediated response. Our co-immunoprecipitation data suggest the interactions between NSs and retinoic acid inducible gene-I (RIG-I) or TANK binding kinase 1 (TBK1). Furthermore, confocal analysis indicates the ability of NSs to sequester RIG-I and related downstream molecules in the cytoplasmic structures called inclusion bodies (IBs). NSs are also capable of inhibiting TBK1-interferon regulatory factor 3 (IRF3) interaction, and therefore prevent the phosphorylation and nuclear translocation of IRF3 for the induction of type I IFN. The ability of SFTSV NSs to interact with and sequester TBK1 and IRF3 in IBs demonstrate an effective yet unique method utilized by SFTSV to evade and suppress host immunity.