• Proceedings of the PSK Conference
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• 2003.04a
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• pp.88-89
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• 2003

In recent days, the bioequivalence(BE) study of domestic drugs on original drug are quite, activated in Korea. This BE study provide not only the bioequivalence of test and reference drug but also produce the population pharmacokinetic(PK) parameters in normal healthy Korean. The BE study can also make it possible to establish a PK/PD model of the drug when the additional pharmacodynamic(PD) data are available. (omitted)

• Proceedings of the PSK Conference
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• 2004.10a
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• pp.90-92
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• 2004

• International Journal of Oral Biology
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• v.34 no.3
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• pp.165-168
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• 2009

Postantibiotic effect (PAE) is defined as the length of time that bacterial growth is suppressed following brief exposure to an antibiotic. In this study, the in vitro PAE, postantibiotic sub-MIC effect (PA SME) and sub-MIC effect (SME) of antibiotics on Treponema denticola ATCC 35405 were investigated. The PAE of doxycycline and metronidazole were 20.3 h and 25.0 h, respectively. The PA SMEs examined by addition of 0.1, 0.2 and 0.3X MICs during the postantibiotic phase of the bacteria for metronidazole were longer than those for doxycycline. In contrast, the SMEs for doxycycline were longer than those for metronidazole. The PA-SME and SME values increased as the concentration of antibiotics increased. The present study illustrates the existence of PAE, PA-SME and SME for several antibiotics against T. denticola, thereby extending the pharmacodynamic advantages of these antibiotics.

• Translational and Clinical Pharmacology
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• v.26 no.4
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• pp.160-165
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• 2018

Indobufen ($Ibustrin^{(R)}$), a reversible inhibitor of platelet aggregation, exists in two enantiomeric forms in 1:1 ratio. Here, we characterized the anti-platelet effect of S- and R-indobufen using response surface modeling using $NONMEM^{(R)}$ and predicted the therapeutic doses exerting the maximal efficacy of each enantioselective S- and R-indobufen formulation. S- and R-indobufen were added individually or together to 24 plasma samples from drug-naïve healthy subjects, generating 892 samples containing randomly selected concentrations of the drugs of 0-128 mg/L. Collagen-induced platelet aggregation in platelet-rich plasma was determined using a Chrono-log Lumi-Aggregometer. Inhibitory sigmoid $I_{max}$ model adequately described the anti-platelet effect. The S-form was more potent, whereas the R-form showed less inter-individual variation. No significant interaction was observed between the two enantiomers. The anti-platelet effect of multiple treatments with 200 mg indobufen twice daily doses was predicted in the simulation study, and the effect of S- or R-indobufen alone at various doses was predicted to define optimal dosing regimen for each enantiomer. Simulation study predicted that 200 mg twice daily administration of S-indobufen alone will produce more treatment effect than S-and R-mixture formulation. S-indobufen produced treatment effect at lower concentration than R-indobufen. However, inter-individual variation of the pharmacodynamic response was smaller in R-indobufen. The present study suggests the optimal doses of R-and S-enantioselective indobufen formulations in terms of treatment efficacy for patients with thromboembolic problems. The proposed methodology in this study can be applied to the develop novel enantio-selective drugs more efficiently.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.214-217
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• 2002

Cyclosporin A (CSA) is a poorly water-soluble cyclic peptide comprising 11 amino acids. It inhibits T-lymphocyte function that plays an important role in the induction of immune response. The potent immunosuppressive activity of CSA has been used for the prevention of rejection following transplantation of liver, kidney and bone marrow, etc. The use of CSA has been often limited by several disadvantages including low bioavailability, narrow therapeutic window, nephrotoxicity, hepatotoxicity and neurotoxicity. Moreover, CSA injection is limited to patients who are unable to take the oral preparations, because it has a risk of anaphylactic shock and nephrotoxicity due to Cremophor EL$\textregistered$, a solubilizing agent used in the commercial intravenous formulation. Owing to above mentioned disadvantages of commercial products, there is a great interest in the development of the alternative dosage forms. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.212-213
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• 2002

Using the isolated perfused rat heart this study investigated 1) the cardiac uptake of idarubicin (IDA), 2) the role of P-glycoprotein (P-gp) in the uptake process, 3) the formation of IDOL from IDA in the heart, and 4) the effect of P-gp inhibitors (verapamil, amiodarone, PSC 833), doxorubicin, hypothermia, xanthine derivatives (caffeine, theophylline) and metabolism inhibitors (rutin, phenobarbital) on the pharmacokinetics and pharmacodynamics of IDA using a mathematical modeling approach. A minimal model was constructed; the differential equations were numerically solved and fitted to the data using the ADAPT II-software package using maximum likelihood estimation assuming that the measurement error has a standard deviation which is a linear function of the measured quantity［1］. (omitted)

• Journal of Pharmaceutical Investigation
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• v.17 no.4
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• pp.205-211
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• 1987

Renal dysfunction can have pronounced effects on the pharmacokinetic and pharmacodynamic characteristics of drugs. Because the exploration of these effects in patients may be limited by ethical and practical considerations, it often become necessary to perform studies on animals with experimental renal failure(ERF). ERF was produced in rats by the administration of uranyl nitrate, glycerol, salicylate, gentamicin and folate in this study. Changes in glomerular filtration rate(GFR) and renal secretion clearance of tetraethylammonium bromide$(CL^{scn}_{TEA})$, together with morphological changes of kidney cortex were evaluated and compared among ERF models. GFR(or glomeruli) and $CL^{scn}_{TEA}$(or renal tubules) were not damaged parallelly in some ERF model rats. Therefore, it seemed to be necessary to adjust dosage regimen of some basic drugs like TEA in renal dysfunction considering the functional changes of renal secretion in addition to glomerular filtration.

• Journal of Pharmaceutical Investigation
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• v.39 no.2
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• pp.111-115
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• 2009

The pharmacokinetics of cyclosporin A (CsA) after single and multiple oral dosing of new CsA self-micro-emulsifying drug delivery system (SMEDDS) in dogs were estimated. A single dose study was performed following a two-way crossover design against six dogs with reference SMEDDS. For a multiple dose study, three dogs were allocated for each drug, and 100 mg of drug was administered daily for 6 days. Whole blood concentration of CsA was analyzed by radio-immunoassay. Both drug showed identical blood concentration profiles in both studies, and no statistical difference was detected in pharmacokinetic parameters. The relative bioavailabilities of test SMEDDS were 91.4% and 89.1%, respectively, in the single dose study and the last day of multiple dose study. Especially, multiple dose study proved the good relationship between C-0/C-2 and AUC for reference SMEDDS, which is an indispensable part of therapeutic drug monitoring. These results suggest newly formulated CsA SMEDDS possibly shows identical pharmacokinetics and pharmacodynamic behaviors in clinical trials.

• Proceedings of the Ginseng society Conference
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• 1980.09a
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• pp.143-150
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• 1980

The purpose of this double-blind study was to study the standardized ginseng-extract (marketed form, GINSANA), in regard to its efficacy on the reaction time, pulmonary function and general health in subjects of various age-groups. The trial was conducted as a double-blind study in a total of 120 subjectsm allocated to different groups, according to age (30 to 39 and 40 to 60 year age-groups), sex and preparation administered (ginseng/placebo). The study lasted 12 weeks and the dosage was fixed at 2 capsules per day. The rusults regarding reaction time and pulmonary function showed significant differences in favour of the GINSANA group, over the placebo group, in the 40 to 60-year-old men and women. In the self-evaluation (performance, mood, concentration) we observed a clear improvement (p < 0.001) in the subjects treated with GINSANA, with the exception of the men age 30-39 years. The results botained, which are specially related to reaction, pulmonary function, self evaluation and tolerability, have shown that GINSANA, as standardized ginseng extract, has a favourable effect on the psychic and physical functions studied. 3. Performance test in top sportsmen before and after 9 weeks' treatment with GINSANA To what extent can GINSANA influence physical performance? It is precisely we the physicians whose task it is to find drugs which in physiological amounts do not have any special pharmacodynamic effects. We were therefore interested in the preparation, GINSANA which was made available to us, since it contains a qualitatively and quantitatively standardized GINSENG EXTRACT and is not doping agent.

• YAKHAK HOEJI
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• v.55 no.5
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• pp.374-378
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• 2011

This study was performed to evaluate enhanced effect of fermented Galgeun tang (GGT) and Ssanghwa tang (SHT) on the anti-platelet aggregation. Platelet aggregation assay was performed In vitro using human platelet rich plasma(PRP) and In vivo using SD-rat plasma by platelet aggregometer. Pharmacodynamic parameters, $E_{max}$ and $EC_{50}$, were calculated using Winnolin. SD-rats administered 1 g/kg of oriental medicine every 12 hr for 8 days. Platelet aggregation was measured by optical method with collagen inducer (4 ${\mu}g$/ml). In In vitro anti-platelet study, $EC_{50}$ of GGT-A was lower than that of GGT-con about 79.13 ${\mu}g$/ml. And $EC_{50}$ of SHT-A and SHT-B was lower than that of SHT-con about 122.73 and 110.15 ${\mu}g$/ml, respectively. It is assumed that fermented GGT and SHT were more effective than original medicine. In multiple administration study, anti-platelet effect was significantly increased both GGT and SHT. Fermented GGT and SHT were more effective than original herbal medicine on anti-platelet aggregation.