• 제목/요약/키워드: IC protection

검색결과 125건 처리시간 0.031초

BMS-191095, a Cardioselective Mitochondrial $K_{ATP}$ Opener, Inhibits Human Platelet Aggregation by Opening Mitochondrial $K_{ATP}$ Channels

  • Cho Mi-Ra;Park Jung-Wook;Jung In-Sang;Yi Kyu-Yang;Yoo Sung-Eun;Chung Hun-Jong;Yun Yeo-Pyo;Kwon Suk-Hyung;Shin Hwa-Sup
    • Archives of Pharmacal Research
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    • 제28권1호
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    • pp.61-67
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    • 2005
  • We evaluated the antiplatelet effects of two classes of ATP-sensitive potassium channel openers $(K_{ATP}\;openers)$ on washed human platelets, and the study's emphasis was on the role of mitochondrial $K_{ATP}$ in platelet aggregation. Collagen-induced platelet aggregation was inhibited in a dose dependent manner by lemakalim and SKP-450, which are potent cardio-nonselective $K_{ATP}$ openers, and also by cardioselective BMS-180448 and BMS-191095 $(IC_{50}\;:\;1,130,\;>\;1,500,\;305.3\;and\;63.9\;{\mu}M,\;respectively)$, but a significantly greater potency was noted for the cardioselective $K_{ATP}$ openers. The latter two $K_{ATP}$ openers also inhibited platelet aggregation induced by thrombin, another important blood-borne platelet activator, with similar rank order of potency $(IC_{50}\;:\;498.0\;and\;104.8{\mu}M\; for\;BMS-180448\;and\;BMS-191095,\;respectively)$. The inhibitory effects of BMS-191095 on collagen-induced platelet aggregation were significantly blocked by a 30-min pretreatment of platelets with glyburide $(1{\mu}M)$ or sodium 5-hydroxyde­canoate$(5-HD,\;100{\mu}M)$, a nonselective and selective mitochondrial $K_{ATP}$ antagonist, respectively, at similar magnitudes; this indicates the role of mitochondrial $K_{ATP}$ in the antiplatelet activity of BMS-191095. However, glyburide and 5-HD had no effect when they were added to the platelet cuvette immediately prior to the addition of BMS-191095. These findings indicate that cardioselective mitochondrial $K_{ATP}$ openers like BMS-191095 are able to exert cardioprotective effects in cardiac ischemia/reperfusion injury via dual mechanisms directed at the inhibition of platelet aggregation and the protection of cardiomyocytes, and both these mechanisms are mediated by mitochondrial$K_{ATP}$.

숙지황 분말을 첨가한 국수의 품질 특성 및 항산화성 (Quality Characteristics and Antioxidant Activities of Noodles Added with Rehmanniae Radix Preparata Powder)

  • 민아영;손아영;김현정;신숙경;김미리
    • 한국식품영양과학회지
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    • 제44권3호
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    • pp.386-392
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    • 2015
  • 본 연구는 숙지황 분말을 이용한 기능성 면류를 제조하기 위해서 숙지황 분말을 밀가루에 0, 2.5, 5, 7.5% 첨가하여 제조한 국수의 품질 특성 및 항산화성을 조사하였다. 숙지황 분말 첨가가 증가함에 따라 국수의 중량, 부피, 함수율은 감소하였고 탁도는 증가하였다. 색도는 숙지황 분말의 첨가량이 증가할수록 L값과 b값은 감소하고 a값은 증가하는 경향을 나타내었다. 수분 함량은 숙지황 분말의 첨가량이 증가할수록 감소하였다. 숙지황 분말 첨가량이 증가할수록 국수의 경도는 증가하였고, 탄력성, 응집성, 검성 및 씹힘성은 감소하였다. 숙지황 분말의 첨가 농도가 증가함에 따라 아밀로그래프상의 호화개시 온도는 증가하였고, 최고 점도와 최종 점도는 감소하였다. 숙지황 분말 첨가 농도가 높아질수록 polyphenol 함량은 증가하였고, DPPH radical 소거능에서 $IC_{50}$값이 감소하였으므로 숙지황 분말 첨가량이 증가할수록 항산화능이 높아지는 것을 알 수 있었다. 관능검사 결과 숙지황 분말 2.5% 첨가 국수가 전체적인 기호도 및 구입의사에서 가장 높게 평가되었다. 이상의 결과로 볼 때 숙지황 분말을 첨가한 기능성 국수의 개발이 가능하였고 기능성을 고려하였을 때는 숙지황 분말 7.5% 첨가가 가장 그 항산화 활성이 우수하였다. 하지만 제품 개발 특성상 관능적 특성을 크게 고려하였을 때, 숙지황 분말을 2.5% 첨가하여 국수를 제조하는 것이 가장 적합한 것으로 사료된다.

가드링 구조에서 전류 과밀 현상 억제를 위한 온-칩 정전기 보호 방법 (An On-chip ESD Protection Method for Preventing Current Crowding on a Guard-ring Structure)

  • 송종규;장창수;정원영;송인채;위재경
    • 대한전자공학회논문지SD
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    • 제46권12호
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    • pp.105-112
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    • 2009
  • 본 논문에서는 $0.35{\mu}m$ Bipolar-CMOS-DMOS(BCD)공정으로 설계한 스마트 파워 IC 내의 가드링 코너 영역에서 발생하는 비정상적인 정전기 불량을 관측하고 이를 분석하였다. 칩내에서 래치업(Latch-up)방지를 위한 고전압 소자의 가드링에 연결되어 있는 Vcc단과 Vss 사이에 존재하는 기생 다이오드에서 발생한 과도한 전류 과밀 현상으로 정전기 내성 평가에서 Machine Model(MM)에서는 200V를 만족하지 못하는 불량이 발생하였다. Optical Beam Induced Resistance Charge(OBIRCH)와 Scanning Electronic Microscope(SEM)을 사용하여 불량이 발생한 지점을 확인하였고, 3D T-CAD 시뮬레이션으로 원인을 검증하였다. 시뮬레이션 결과를 통해 Local Oxidation(LOCOS)형태의 Isolation구조에서 과도한 정전기 전류가 흘렀을 때 코너영역의 형태에 따라 문제가 발생하는 것을 검증하였다. 이를 통해 정전기 내성이 개선된 가드링 코너 디자인 방법을 제안하였고 제품에 적용한 결과, MM 정전기 내성 평가에서 200V이상의 결과를 얻었다. 통계적으로 Test chip을 분석한 결과 기존의 결과 대비 20%이상 정전기 내성이 향상된 것을 확인 할 수 있었다. 이 결과를 바탕으로 BCD공정을 사용하는 칩 설계 시, 가드링 구조의 정전기 취약 지점을 Design Rule Check(DRC) 툴을 사용하여 자동으로 찾을 수 있는 설계 방법도 제안하였다. 본 연구에서 제안된 자동 검증방법을 사용하여, 동종 제품에 적용한 결과 24개의 에러를 검출하였으며, 수정 완료 제품은 동일한 정전기 불량은 발생하지 않았고 일반적인 정전기 내성 요구수준인 HBM 2000V / MM 200V를 만족하는 결과를 얻었다.

Anti-thrombic Properties of the Oriental Herbal Medicine, Daejowhan

  • Chang Gyu-Tae;Kim Jang-Hyun
    • 동의생리병리학회지
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    • 제19권5호
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    • pp.1391-1398
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    • 2005
  • The anti-thrombic properties of the oriental herbal medicine Daejowhan(DJW, 大造丸) which consists of 11 kinds of herbs (indicated as ratio) of Rehmanniae Radix 24%, Hominis Placenta 5%, Testudinis Carapax 9%, Eucommiae Cortex 9%, Asparagi Radix 9%, Phellodendri Cortex 9%, Achyranthis Radix 7%, Liriopis Tuber 7%, Angelicae Sinensis Radix 7%, Ginseng Radix 5% and Schizandrae Fructus 3% were investigated. The water extracts from DJW inhibited Platelet-activating factor(PAF) induced platelet aggregation. DJW was extracted with methanol and further fractionated by ethylacetate. A 70% methanol extract showed a strong inhibition against PAF-induced aggregation in vitro and in vivo assays. The ethylacetate soluble fraction was shown to have inhibitory effect on PAF-induced platelet aggregation in vitro assay. The ethylacetate soluble fraction specially protected against the lethality of PAF, while verapamil did not afford any protection. These results indicate that the water extracts and alcoholic-fractions inhibit the action of PAF in vivo by an antagonistic effect on PAF, so that it may be useful in treating disorders caused by PAF, such as acute allergy, inflammation, asthma, gastrointestinal ulceration, toxic shock and so forth. DJW was investigated regarding its assumed anti-thrombic action on human platelets which was deduced from its ability to suppress Arachidonic acid(AA)-induced aggregation, exocytosis of ATP, and inhibition of Cyclooxygenase(COX) and Thromboxane synthase(TXS) activity. The latter two effects were estimated from the generation of Prostaglandin $E_2(PGE_2)$ and Thromboxane $A_2(TXA_2)$ respectively. Exogenously applied AA ($100{\mu}mol/{\ell}$) provoked a $89\%$ aggregation of platelets, the release of 14 pmol ATP, and the formation of either 225 pg $TXA_2$ or 45 pg $PGE_2$, each parameter being related to 106 platelets. An application of DJW 5 min before AA dose-dependently diminished aggregation, ATP-release and the synthesis of $TXA_2$ and $PGE_2$ with $IC_{50}$ values of 74, 108, 65, $72{\mu}g/m{\ell}$, respectively. The similarity of the $IC_{50}$ values suggest an inhibition of COX by DJW as primary target, thus suppressing the generation of $TXA_2$ which induces aggregation of platelets and exocytosis of ATP by its binding on $TXA_2$-receptors.

안전하지 않은 I/O핀 노이즈 환경에서 MCU 클럭 보호를 위한 자동 온칩 글리치 프리 백업 클럭 변환 기법 (Automatic On-Chip Glitch-Free Backup Clock Changing Method for MCU Clock Failure Protection in Unsafe I/O Pin Noisy Environment)

  • 안중현;윤지애;조정훈;박대진
    • 전자공학회논문지
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    • 제52권12호
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    • pp.99-108
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    • 2015
  • 클럭 펄스에 동기 되어 동작하는 임베디드 마이크로컨트롤러는 미션 크리티컬한 응용환경에서 입력 클럭에 가해지는 급격한 전기적 왜란의 영향에 의해 오동작이 발생되기 쉽다. 다양한 외부 전기적 노이즈에 대한 내성 있는 시스템 동작이 요구되며 시스템 클럭 관점에서 견고한 회로 디자인 기술이 점차 중요한 이슈가 되고 있다. 본 논문에서는 이러한 시스템의 비이상적인 상황을 방지하기 위해 자동 클럭 에러 검출을 위한 온 칩클럭 컨트롤러 구조를 제안한다. 이를 위해 에지 검출기, 노이즈 제거기와 글리치 프리 클럭 스위칭 회로를 적용하였고, 에지 검출기는 입력 클럭의 비이상적인 저주파수 상태를 검출하는데 사용 되었으며, 딜레이 체인 회로를 이용한 클럭 펄스의 노이즈 제거기는 글리치 성분을 검출 할 수 있도록 하였다. 이렇게 검출된 입력 클럭의 비이상적인 상황은 글리치 프리 클럭 변환기에 의해 백업 클럭으로 스위칭하게 된다. 회로 시뮬레이션을 통해 제안된 백업 클럭 변환기의 동작을 검증하였고 테스트환경에서 방사노이즈를 인가하였을 때 시스템 클럭의 내성에 대한 주파수 특성을 평가하였다. 본 기법을 범용 MCMCU 구조에 추가적으로 적용하여 작은 하드웨어의 추가만으로도 시스템 클럭의 안전성을 확보하는 하나의 방법을 제시한다.

Differentially Expressed Genes by Methylmercury in Neuroblastoma cell line using suppression subtractive hybridization (SSH) and cDNA Microarray

  • Kim, Youn-Jung;Chang, Suk-Tai;Yun, Hye-Jung;Ryu, Jae-Chun
    • 한국환경독성학회:학술대회논문집
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    • 한국환경독성학회 2003년도 춘계학술대회
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    • pp.187-187
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    • 2003
  • Methylmercury (MeHg), one of the heavy metal compounds, can cause severe damage to the central nervous system in humans. Many reports have shown that MeHg is poisonous to human body through contaminated foods and has released into the environment. Despite many studies on the pathogenesis of MeHg-induced central neuropathy, no useful mechanism of toxicity has been established so far. In this study, two methods, cDNA Microarray and SSH, were performed to assess the expression profile against MeHg and to identify differentially expressed genes by MeHg in neuroblastoma cell line. TwinChip Human-8K (Digital Genomics) was used with total RNA from SH-SY5Y (human neuroblastoma cell line) treated with solvent (DMSO) and 6.25 uM (IC50) MeHg. And we performed forward and reverse SSH method on mRNA derived from SH-SY5Y treated with DMSO and MeHg (6.25 uM). Differentially expressed cDNA clones were sequenced and were screened by dot blot and ribonuclease protection assay to confirm that individual clones indeed represent differentially expressed genes. These sequences were identified by BLAST homology search to known genes or expressed sequence tags (ESTs). Analysis of these sequences may provide an insight into the biological effects of MeHg in the pathogenesis of neurodegenerative disease and a possibility to develop more efficient and exact monitoring system of heavy metals as environmental pollutants.

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Fractionation and Characterization of Fractions with High Antioxidative Activity from the Gelatin Hydrolysates of Korean Rockfish Sebastes schlegelii Skin

  • Kim, Hyung-Jun;Park, Kwon-Hyun;Shin, Jun-Ho;Lee, Ji-Sun;Heu, Min-Soo;Lee, Dong-Ho;Kim, Jin-Soo
    • Fisheries and Aquatic Sciences
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    • 제14권3호
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    • pp.168-173
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    • 2011
  • The purpose of this study was to obtain a fraction with high antioxidative activity from second rockfish gelatin hydrolysates (SRSGHs), which were hydrolyzed with Alcalase and Flavourzyme through ultrafiltration membranes with serial digestions for 1 and 2 h, respectively, and to investigate the feasibility of this fraction as a potential functional food ingredient. Among various fractions that were ultrafiltered from the SRSGH with four types of membrane (1, 5, 10, and 30 kDa), the SRSGH-III fraction, which permeated the 10 kDa membrane but not the 5 kDa membrane, showed the highest antioxidant activity (protection factor=5.13) and angiotensin-I-converting enzyme-inhibiting activity ($IC_{50}$=0.82 mg/mL). These results suggest that the SRSGH-III fraction from the SRSGH can be used as a functional food ingredient. However, further studies examining its antioxidant activity in vivo as well as the different antioxidant mechanisms are needed.

Identification of Soluble Epoxide Hydrolase Inhibitors from the Seeds of Passiflora edulis Cultivated in Vietnam

  • Cuong, To Dao;Anh, Hoang Thi Ngoc;Huong, Tran Thu;Khanh, Pham Ngoc;Ha, Vu Thi;Hung, Tran Manh;Kim, Young Ho;Cuong, Nguyen Manh
    • Natural Product Sciences
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    • 제25권4호
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    • pp.348-353
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    • 2019
  • Soluble epoxide hydrolases (sEH) are enzymes present in all living organisms, metabolize epoxy fatty acids to 1,2-diols. sEH in the metabolism of polyunsaturated fatty acids plays a key role in inflammation. In addition, the endogenous lipid mediators in cardiovascular disease are also broken down to diols by the action of sEH that enhanced cardiovascular protection. In this study, sEH inhibitory guided fractionation led to the isolation of five phenolic compounds trans-resveratrol (1), trans-piceatannol (2), sulfuretin (3), (+)-balanophonin (4), and cassigarol E (5) from the ethanol extract of the seeds of Passiflora edulis Sims cultivated in Vietnam. The chemical structures of isolated compounds were determined by the interpretation of NMR spectral data, mass spectra, and comparison with data from the literature. The soluble epoxide hydrolase (sEH) inhibitory activity of isolated compounds was evaluated. Among them, trans-piceatannol (2) showed the most potent inhibitory activity on sEH with an IC50 value of 3.4 μM. This study marks the first time that sulfuretin (3) was isolated from Passiflora edulis as well as (+)-balanophonin (4), and cassigarol E (5) were isolated from Passiflora genus.

WDFT를 이용한 자동차 엔진의 실화검출 (Detection of Misfire in Car Engines using Walsh Discrete Fourier Transform)

  • 김종부;이태표;오정수;임국현
    • 전자공학회논문지T
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    • 제35T권1호
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    • pp.67-74
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    • 1998
  • 자동차 배기가스의 증가요인인 실화발생을 감지하고 실화가 발생하는 기통까지 판별하기 위하여 종래에는 크랭크각속도를 측정하는 방법을 이용하였으나 이 방법은 고속의 회전시 감지가 어려운 문제를 가지고 있다. 이러한 문제를 해결하기 위해서 본 논문은 이산 월쉬-푸리에(Walsh Discrete Fourier Transform; WDFT)를 이용하여 고속의 엔진회전수에서도 실화발생여부를 판단 가능하게 하였고, 월쉬함수의 Moving window방식을 이용하여 다기통 실화발생에 대한 기통판별까지 가능하게 하였다. 이상의 내용을 시스템으로 구현하여 무부하 Idle상태와 운전상태(Drive)에서 시험한 결과도 실화발생여부를 감지하는데 기존의 방법보다 더 효과적임을 알 수 있었다.

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The effect of L-carnitine in the expression of matrix metalloproteinases by human dermal fibroblasts

  • Yoon, Eun-Jeong;Lee, Kyoung-Eun;Sim, Kwan-Sup;Lee, Bum-Chun;Pyo, Hyeong-Bae;Choe, Tae-boo
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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    • pp.12-25
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    • 2003
  • L-camitine ($\beta$ -hydroxy-${\gamma}$ -trimethyl-ammoniumbutyric acid) is a small water-soluble molecule important in mammalian fat metabolism. It is essential for the normal oxidation of fatty acids by the mitochondria, and is involved in the trans-esterification and excretion of acyl-CoA esters. In this paper, to investigate the relationship between aging and L-camitine, we investigated the effects of in vitro MMP inhibition and activity and expression of UVA-induced MMP 1 in human skin fibroblasts. Fluorometric assays of the proteolytic activities of MMP-l were performed using fluorescent collagen substrates. ELISA (enzyme linked immuno sorbent assay), gelatin-substrate zymography, and RT-PCR ELISA techniques were used for the effects of L-camitine on MMP expression and activity, MMP mRNA expression in UVA irradiated fibroblast. L-camitine inhibited the activities of MMP-l in a dose-dependent manner and the $IC_{50}$/ values calculated from semi-log plots were 2.45mM, and L-carnitine showed strong inhibition on MMP-2 (gelatinase) activity in UVA irradiated fibroblast by zymography. Also, UVA induced MMP expression was reduced 40% by treated with L-carnitine, and MMP-l mRNA expression was reduced dose-dependent manner. Therefore L-carnitine was able to significantly inhibition the MMP activity, regulation of MMP expression in protein and mRNA level. All these results suggest that L-carnitine may be useful as new anti-aging cofactor for protection against UVA induced MMP expression and activity.

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