http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
적출관류 간에서 대황, 마황 및 황금이 7-에톡시쿠마린의 대사에 미치는 영향
최기환(Ki Hwan Choi),김순선(Soon Sun Kim),박윤주(Youn Joo Park),정혜주(Hye Joo Chung),안미령(Mee Ryung Ahn),서수경(Soo Kyung Suh),신윤용(Yhun Yhong Sheen),김동섭(Dong Sup Kim),장영섭(Young Sup Chang) 대한약학회 1998 약학회지 Vol.42 No.4
In order to study the effects of Rhei rhizoma, Ephedrae herba and Scutellariae radix on hepatic metabolism, we examined the pretreatment effect of those on the metabolism of 7-ethoxycoumarin (EC). Water extracts (1g/kg) of Rhei rhizoma, Ephedrae herba and Scutellariae radix were administered orally to rats for 7 days, respectively. Livers were then isolated and perfused with 100mcM EC for 2 hours. The metabolites of EC, 7-hydroxycoumarin, sulfate conjugate and glucuronide conjugate were measured in the perfusates. The amount of glucuronide conjugates was decreased in Rhei rhizoma pretreated rats (p<0.01), however. 7-hydroxycoumarin was increased in Ephedrae herba pretxeated rats (p<O.OD. We examined whether the change of enzyme activity is related to the change of cytochrome P4501A1 a n d P4502B1 mRNA level in the perfused rat liver, which are responsible for EC metabolism. CYPlAl a n d CYP2B1 mRNA level was increased, which was not statistically significant with rhei rhizoma nor ephedrae herba pretreatment. We also assessed the hepatotoxicity of Rhei rhizoma. Ephedrae herba a n d Scutellariae radix. The activities of ALT and AST were assayed at 24 hours after 7 days administration. Only the ratio of ALT over AST was increased in ephedrae herba pre treated rats (p<0.05). Lipid peroxidation was increased in Rhei rhizoma treatment (p<0.05). while histopathological examination performed after liver perfusion did not show a n y difference compared with vehicle treatment. These results suggest that Ephedrae herba pretreatment increases the o-deethy-lation of 7-ethoxycoumarin in rats, which may be mediated b y CYPlAl mRNA induction.
최기환(Ki Hwan Choi),박인숙(In Sook Park),김동섭(Dong Sup Kim),정혜주(Hye Joo Chung) 대한약학회 2000 약학회지 Vol.44 No.3
Because nonsteroidal anti-inflammatory drugs are reported to cause fluid retention and hypertension by inhibition of prostaglandin synthesis, the effects of piroxicam on pharmacodynamics and pharmacokinetics of nifedipine were studied in male spontaneously hypertensive rats. They received nifedipine (0.5mg/kg) alone or combined with piroxicam (5mg/kg) intravenously Plasma levels norepinephrine, an index of sympathetic stimulation, were measured prior to each treatment and 5 min after drug administration. Changes in blood pressure were examined serially and blood samples for analysis of nifedipine were also taken for 6hr following drug administration. Plasma nifedipine concentrations were assayed by HPLC and pharmacokinetic parameters were calculated. Blood pressure was reduced (p<0.01), but plasma norepinephrine level was increased (p<0.05) by nifedipine administration. Anti-hypertensive effect of nifedipine was potentiated (p<0.05) by piroxicam coadministration, but effect of nifedipine on plasma norepinephrine level was not affected. In case of rats received nifedipine and piroxicam, plasma nifedipine concentrations were higher (p<0.05) than those from rats received nifedipine alone at 2, 3, 4, 5 and 6 hours following drug administration. The area under the plasma concentration vs. time curve was increased (p<0.05), while the elimination rate constant was decreased (p<0.01) by piroxicam coadministration. No significant differences were observed in the plasma clearance, apparent volume of distribution and elimination half-life. Thus, piroxicam not only potentiated antihypertensive effect of nifedipine, but also altered nifedipine pharmacokinetics in the rats. It is concluded that the potentiation of nifedipine antihypertensive effect might correlate with the increment of its plasma concentration by piroxicam coadministration.
DTO 반응에서 촉매수명과 경질 올레핀 선택도에 미치는 SAPO-34의 산 처리 효과
최기환 ( Ki Hwan Choi ),이동희 ( Dong Hee Lee ),김효섭 ( Hyo Sub Kim ),박주식 ( Chu Sik Park ),김영호 ( Young Ho Kim ) 한국공업화학회 2015 공업화학 Vol.26 No.2
Effects of the post-acid treatment of SAPO-34 sample by hydrochloric acid were investigated to enhance the catalytic performance in DTO reaction. Uniformly sized SAPO-34 samples with cubic-like morphology were prepared by hydrothermal method using TEAOH and DEA as the structure directing agents. It was modified in terms of the HCl concentration and treating time. As a result, the total surface area and micropore volume for the well modified samples increased and the total acid site was somewhat decreased along with the erosion of the external surface. Especially, the catalytic lifetime and light olefins selectivity for acid treated SAPO-0.2 M (3 h) samples were considerably enhanced compared with those of untreated SAPO-34 samples. It indicates that the deactivation by coke formation proceeds mainly at the pore entrance on the external surface. Therefore, the acid treatment was confirmed to be a simple method which can significantly improve the catalytic performance by modifying the external surface of SAPO-34 catalyst.
안전성약리시험의 Good Laboratory Practice 평가기술연구
최기환(Ki Hwan Choi),박기숙(Ki Sook Park),이윤희(Yun Hee Lee),나한광(Hang-Kwang Na),윤재석(Jae Suk Yun),김동섭(Dong-Sup Kim),김주일(Joo-Il Kim) 한국독성학회 2006 Toxicological Research Vol.22 No.2
Safety pharmacology studies are conducted to investigated the potential undesirable pharmacodynamic effects of a substance on physiological functions in relation to exposure in the therapeutic range and above. In the International Conference on Harmonisation (ICH), the guideline “S7A : Safety Pharmacology Studies for Human Pharmaceuticals” has been developed and reached Step 5 of the ICH process in 2001. Now the Korea Food and Drug Administration (KFDA) are going to transfer “The Guideline for General Pharmacology” into “The Guideline for Safety Pharmacology”. Safety pharmacology studies should be performed in compliance with Good Laboratory Practice (GLP). Thus, the present paper reviews the Japanese GLP guidelines for pharmaceuticals to help the conduct and inspection of safety pharmacology studies in compliance with GLP. We also reviewed the ICH guidelines “S7B revised : The Nonclinical Evaluation of the Potential for Delayed Ventricular Repolarization (QT Interval Prolongation) by Human Pharmaceuticals” and “E14 : The Clinical Evaluation of QT/QTc Interval Prolongation and Proarrhythmic Potential for Non-antiarrhythmic Drugs” to apply our drug approval systems.