• 대한수의학회지
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• 제40권3호
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• pp.471-478
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• 2000

새로운 항HIV 후보물질인 19개의 KR-V 경구제제의 생체이용률을 평가하기 위해 랫드에서 정맥 및 경구투여후 약물동태를 연구하였다. 혈장내 KR-V 화합물들의 검출은 HPLC-UVD 법을 이용하여 분석하였다. 19개 KR-V series 중 KR-V 3, 10, 14, 16 및 18-1만이 랫드에서 경구로 흡수되어 생체이용성을 나타내었다. 10mg/kg의 정맥투여후 약물 통태 연구에 있어서는 5개물질, KR-V3, 10, 14, 16 및 18-1의 소실 반감기는 서로 비슷하였으나 KR-V 3, 10, 14 및 16의 총청소율($CL_{total}$, >4L/hr/kg)은 KR-V 18-1(1.1L/hr/kg) 보다 유의성있게 높았다. KR-V 3, 10, 14 및 16에 비해 KR-V3 18-1이 혈중곡선하면적(AUC, $8.97{\mu}g{\cdot}hr/ml$)은 크고 겉보기분포용적(Vd, 0.58L/kg)은 적었다. 50mg/kg의 경구투여후 약물동태 연구에 있어서는 KR-V 18-1의 반감기가 다른 4개의 물질에 비해 비록 짧았지만 경구 AUC($3.659{\mu}g{\cdot}hr/ml$), 최고혈중농도($C_{max}$, $1.891{\mu}g/ml$) 는 현저히 높았다. 또한 별도의 in virus 실험결과 생체이용률을 나타낸 이들 5개의 물질들 중 KR-V 18-1만이 HIV-1 돌연변이종(mutants)에 대한 억제효과를 나타내었다. 따라서 KR-V 18-1이 항에이즈(AIDS)제의 새로운 후보물질 혹은 선도물질로서 가능성이 기대되었다.

• 대한수의학회지
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• 제40권4호
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• pp.741-746
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• 2000

최근 새로 개발중인 항AIDS치료제 KR-V 시리즈를 대상으로 HPLC-UV 검출법을 이용해 랫드 혈장중에서 분석법을 검토하였다. 분석컬럼은 $C_{18}$($5{\mu}m$, $250{\times}2.0mm$ I.D.)을 이용하였으며 이동상은 물과 ACN의 혼합액(40/60, v/v)으로 하였다. 이상의 조건에서 모든 KR-V 물질들은 용출시간 4-12분에 비교적 신속하게 잘 분리되었으며 정량한계는 15-30 ng/ml, 혈장중 회수율은 KR-V 2, 7 및 15를 제외하고는 85%(C.V. <10%) 이상으로 나타내었다. Ester 구조를 포함하고 있는 KR-V 2, 7 및 15는 혈장중에서 극히 불안정하여 유도체 개발의 분자설계상 제외시키는 것이 좋을 것으로 사료되었다. 결론적으로 본 HPLC-UV 검출법온 KR-V 시리즈 물질들의 약물동태연구를 위한 약물 분석법의 유효한 방법으로 검토되었다.

• 한국가금학회지
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• 제39권2호
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• pp.113-120
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• 2012

본 연구를 통하여 Vero 세포에서 강독형 NDV인 Kr005주를 55대 연속 계대하여 Vero 세포에 적응된 Kr005/V 주를 작성하였다. Kr005/V 주는 Vero 세포에서 $10^{7.8}/mL$의 높은 바이러스 증식성을 보였으며, 감염세포는 cell rounding과 같은 CPE를 형성하였다. 또한 이열성(heat labile) NDV Kr005주와 달리 NDV Kr005/V 주는 내열성(thermostable)을 보였다. 계태아에서 평균 치사 시간(MDT)를 측정한 결과, 강독형인 Kr005주(49.6시간의 MDT)와 달리 Kr005/V 주는 120시간이상의 MDT를 보여 약독형 바이러스(lentogenic virus)로 분류되었다. Kr005/V 주의 HN 단백질과 F 단백질의 염기서열을 분석한 결과, HN 단백질의 443번째 아미노산에서만 변이(T에서 S)가 관찰되었다. Kr005/V 주와 Vero 세포를 사용하여 야외 닭 혈청을 대상으로 혈청중화 항체가를 측정한 결과, Kr005주와 CEF 세포를 사용하여 측정한 혈청중화 항체가와 97%의 상관성을 나타내었다.

• 약학회지
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• 제41권1호
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• pp.117-125
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• 1997

The pharmacological effects of benzopyran potassium channel openers (lemakalim, KR-30450 and KR-30818) on the occlusion/reperfusion-induced myocardial infarction were investigat ed. In anesthetized rats, subjected to 45-min occlusion of the left anterior descending coronary artery (LAD) followed by 90-min reperfusion, the infarct size was measured by calculating the ratio of infarct zone to area at risk (IZ/AAR) with the Evans blue/TTC technique. Rats were intravenously given vehicle (1% DMSO), lemakalim, KR-30450, and KR-30818 alone or in combination with a selective K$_{ATP}$ blacker glibenclamide, 30 min prior to coronary occlusion. Compared to vehicle, lemakalim (30 ${\mu}$g/kg i.v.), the active enantiomer of cromakalim, had a tendancy to decrease infarct size. KR-30450(30 ${\mu}$g/kg, i.v.). the newly synthetized potassium channel openers (PCOs), caused a reduction of infarct size (from 70${\pm}$4%to 57${\pm}$5%). but KR-30818 (30 ${\mu}$g/kg, i.v.), a metabolite of KR-30450. did not modify infarct size. It seem ed likely that glibenclamide (0.3mg/kg, i.v.), given in combination, reduced the effects of these PCOs, especially KR-30450 (30 ${\mu}$g/kg, i.v.) on the infarct size. These results indicate that. in the coronary occluded rat model of ischemia, lemakalim and KR-30450 may exert cardioprotective activity through a reduction of infarct size, the effect being considered related to the opening of K$_{ATP}$ channel.

• 한국임상약학회지
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• 제6권2호
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• pp.32-40
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• 1996

The electrophysiological effects of benzopyran potassium channel openers (PCOs: lemakalim, KR-30450 and KR-30818) on the ischemia/reperfusion-induced arrythmias were investigated. In anesthetized rats, subjected to 45 min occlusion of the left anterior descending coronary artery (LAD) followed by 90 min reperfusion, ventricular arrythmias were identified according to the Lambeth Conventions by lead II ECG. Rats were intravenously given vehicle ($1\%$ DMSO), lemakalim, KR-30450, and KR-30818 alone or in combination with a selective $K_{ATP}$ blocker glibenclamide, 30 min prior to coronary occlusion. Compared to vehicle, lemakalim ($30{\mu}g/kg$ i.v.), the active enantiomer of cromakalim, had a tendancy to increase the duration of ventricular tachycardia (Vl) and ventricular fibrillation (VF), the number of premature ventricular complexes (PVC) and the incidence of VF, especially in the early post-occlusion peroid ($0\~15$ min), while increasing ST-segment elevation. Both KR-30450 ($30{\mu}g/kg$, i.v.) and KR-30818 (30, $100{\mu}g/kg$, i.v.) showed similar proarrhythmic effects to lemakalim (PVC, duration of VT, and incidence of VF) with a tendancy to decrease the duration of VF and ST-segment elevation. Unlike other PCOs, however, glibenclamide (0.3, 1.0 mg/kg) had opposite effects on the induction of arrhythmias (PVC, the duration of VF); it had a tendancy to increase the duration of VT with a slight elevation of ST-segment. It seems likely that glibenclamide (0.3 mg/kg, i.v.), reduced the effects of lemakalim or KR-30450 ($30{\mu}g/kg$, i.v.) on arrhythmias (PVC, VT, VF and ST-segment). These results indicate that, in the coronary occluded rat model of ischemia, lemikuiln and KR-30450 exert a proarrhythmic activity, the effect being considered related to the opening of KATP channel.

• 반도체디스플레이기술학회지
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• 제6권4호
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• pp.11-15
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• 2007

As preparing electrode for the OLED with the sputtering process, in order to be lower damage of the bottom organic layer and increase the life-time of the OLED, we prepared Al electrode for that by using Facing Targets Sputtering (FTS) system. Al electrode directly deposited on the cell (LiF/EML/HTL/Bottom electrode). Deposition condition was the working gas (Ar, Kr and Ar+Kr) and working gas pressure (1 and 6 mTorr). The film thickness and I-V curve of Al/cell were evaluated by a $\acute{a}$-step profiler and a semiconductor parameter (HP4156A) measurement. The thin film surface image was observed by a Atomic Force Microscope (AFM). In result, in comparison with about 11 [V] of the turn-on voltage of Al/cell with using the pure Ar gas, when Al thin film was deposited using the Ar-Kr mixture gas, the surface morphology was improved in some region and the turn-on voltage of Al/cell could be decreased to about 7 [V].

• Archives of Pharmacal Research
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• 제25권5호
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• pp.647-651
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• 2002

An LC/MS/MS method for the simultaneous determination of a neuroprotective agent for ischemia-reperfusion damage, KR-31378 and its N-acetyl metabolite KR-31612 in human plasma was developed. KR-31378, KR-31612 and the internal standard. KR-31543 were extracted from human plasma by liquid-liquid extraction. A reverse-phase HPLC separation was performed on Luna phenylhexyl column with the mixture of acetonitrile-5 mM ammonium formate (55:45, v/v) as mobile phase. The detection of analytes was performed using an electrospray ionization tandem mass spectrometry in the multiple reaction monitoring mode. The lower limits of quantification for KR-31378 and KR-31612 were 2.0 ng/ml. The method showed a satisfactory sensitivity, precision, accuracy, recovery and selectivity.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.123-123
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• 1998

A number of uracil derivatives have been developed as anti-AIDS drugs having a mechanism of inhibiting cellular reverse transcriptase. A simple and rapid assay technique for recently synthesized KR-V analogues was developed using a high-performance liquid chromatography, and oral pharmacokinetics was examined for assessing their oral bioavailabilites. Plasma samples were analyzed by reversed-phase HPLC using an ODS column with an ultraviolet detection system. All the analogues were eluted within 12 min and the LOQ was 15-30 ng/$m\ell$. The extraction recoveries were higher than 85%, except KR-V1039, 1068 and 1720 having ester group. This chromatic method was well applied to the kinetic studies for KR-V analogues. Among 16 analogues tested in the present work, the 6 compounds including KR-V1123, 1122, 1784, 1783, 1736 and 1700 were found to be bioavailable for oral administration to rats.

• 약학회지
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• 제33권3호
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• pp.167-174
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• 1989

KR-1008 and KR-30006 are 1,4-dihydropyridine derivatives, new vasodilatory calcium antagonists from KRICT. Calcium antagonistic properties of the compounds were studied in the isolated heart (Langendorff preparation), pulmonary artery (vasodilation), and in the papillary muscle (negative inotropic effect) of the guinea pig. Antihypertensive effect were also investigated after i.v. or oral administration in the SHR (spontaneously hypertensive rat). They produced a sigificant inhibition of Ca-induced contraction in the guinea pig pulmonary artery at the concentrations of above $10^{-8}M$. The negative inotropic effect of the electrically stimulated papillary muscle appeared from the concentration of $10^{-6}M$, which is about hundred times higer than the concentration of vasodilation effect. Left ventricular pressure also decreased from the concentration of $3\;{\times}\;10^{-6}M$ in KR-1008 and KR-3006 in the Langendorff heart preparations. Coronary flow rate increased from $10^{-6}M$ in KR-1008 and nicardipine and appeared no change in KR-30006. The antihypertensive effect of KR-1008 (EC 20: $2.9\;{\mu}g/kg$) was potent more than nicardipine (EC 20: $3.4\;{\mu}g/kg$) and than Kr-30006 (EC 20: $6.8\;{\mu}g/kg$) was, after i.v. bolus injection in the anesthetized SHR. The antihypertensive effect in the conscious SHR appeared 30 minutes after oral administration of 10 mg/kg and persisted 4 hrs in KR-1008 and 12 hrs in KR-30006. Heart rate tended to increase for 0.5-1 hr after oral administration of the test compounds.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.143.3-144
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• 2003

A Korean isolate of Pepper mild mottle virus (PMMoV-Kr) was isolated from a diseased pepper crop in Chunchon, Korea. The isolate was biologically purified on Nicoticaa tabacum cv. Xanthi-nc by successive single local transfer steps, and propagated on N. tabacum cv. Samsun. PMMoV-Kr could systemically infect on N. glauca, N. benthmiana, N. occidentalis and Lycopersicon esculentum, which is typical of known isolates of PMMoV. PMMoV-Kr belongs to the pathotype P1,2 based on pepper-tobamoviral indicator experiments; Capsicn chinone harboring L3 gene revealed resistant (necrotic local lesion on inoculated leaf, HR) whereas L+, L1 and L2 pepper plants expressed susceptible reactions of mosaic systemic symptoms for the isolate. To confirm the pathology and delineate symptom determinant of the isolate, full-length cDNAs of PMMoV-Kr were amplified by RT-PCR with a primer set corresponding to the 5'- and 3'-ends of PMMoV. The RT-PCR molecules amplified from genome RNA of the isolate was cloned into the pUC18 vector. Full-length cDNA clones constructed under the control of the T7 RNA promoter could be successfully transcribed to produce in vitro transcript RNA. Infectivity of the capped transcripts and its progeny virus was verified by Western blot and RT-PCR analyses.