• Korean Journal of Clinical Pharmacy
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• v.20 no.2
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• pp.99-106
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• 2010

Drugs mostly represent an efficacy or an adverse effect according to their dosage and/or plasma concentrations. Therefore, to investigate the pharmacokinetic behavior of drugs including herbal medicines is necessary both to maximize the drug action and to minimize the adverse effect. To date, pharmacokinetic studies of herbal medicines have been conducted by some experts in this field on the bases of science and knowledge in Korea. On the other hand, in advanced countries, a typical series of pharmacokinetic studies has been conducted by using a harmonized guidance established. Consequently, an administrative support on these studies has to be needed in Korea as well. This study aimed to establish a draft guidance on pharmacokinetic studies of herbal medicines in non-clinical and clinical studies. Literatures previously published as well as guidances in the US, Europe and Japan were summarized for the present guidance. Effect of herbal medicines was listed on the proteins in charge of drug metabolism and transportation, as well as on the pharmacokinetics of chemical drugs. The present suggestion might be helpful to proceed pharmacokinetic studies of herbal medicines efficiently, and further polish should be needed in terms of an administrative point of view.

• Journal of Life Science
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• v.9 no.3
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• pp.241-247
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• 1999

Antibiotics have been routinely used to control the disease of farm-raised animals in the aquaculture facilities without any criterion based on a pharmacokinetic study. This lack of information on the effective usage of antibiotics would have brought the farmers to use excessive and/or less dosages, causing the advent of drug-resistant bacteria as well as economic loss and possible contamination of the local farming area. Until recently, few studies on a detailed manual for the antibiotic usage including chemotherapy procedure, dosage, and treatment schedule of the aquatic antibiotics have been conducted throughout the world. To the worse, there is no available criterion for optimal usage of aquatic antibiotics to control diseases in aquatic farms in this country because every country has its own aquacultural system. Therefore, based on the previous studies on the usage of the various antibiotics, our studies are to focus on the development of optimal method for the detection of various antibiotics on the fate of antibiotics applied to the fish, including absorption, circulation, and secretion physiology. Pharmacokinetic study were to sep up the optimal detective condition against residual antibiotics of fish by HPLC. The grinding pefloxacin for 15 min is most effective in dissolution test and pharmacokinetic parameters. Pharmacokinetic parameters were satisfactory for 15 min-grinding products and they can be explained as one-compartment model.

• YAKHAK HOEJI
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• v.34 no.1
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• pp.40-46
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• 1990

Pharmacokinetic studies on praziquantel in rabbits were performed in this paper. The pharmacologically active parent drug was separated from the pharmacologically inactive metabolites by HPLC method. The pharmacokinetic parameters of parent drug were obtained. In vitro partition to blood cells of praziquantel was measured. The mean value (n = 3) of partition to blood cells was 44% at concentrations between $1\;{\mu}g/ml$ and $40\;{\mu}g/ml$. Therefore, the relatively high partition to blood cells should be considered in further pharmacokinetic studies on praziquantel.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1571-1574
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• 2003

This paper describes an inductively coupled plasma emission spectrometric method for the analysis of Fe in rat plasma. Calibration curves were obtained in the range of 0.125-1.50 ${\mu}g{\cdot}mL^{-1}$. The relative standard deviation ranges from 5.93% to 6.80%, and accuracy was between 87.6 and 102.0%. Dilution with water had no influence on the performance of the method, which could then be used to quantify Fe concentration in plasma up to 0.50 ${\mu}g{\cdot}mL^{-1}$. The limit of quantification was 0.10 ${\mu}g{\cdot}mL^{-1}$. At this level, the average relative standard deviation was 6.8%. The results indicate that the method meets the accuracy and precision requirements for the pharmacokinetic studies. The Fe concentration in rat plasma was measured and the main pharmacokinetic parameters were calculated by Topfit 2.0 (GmbH. Shering AG, Godecke AG, Germany).

• Korean Journal of Clinical Pharmacy
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• v.22 no.1
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• pp.21-29
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• 2012

Modern biologics are biotechnology-derived therapeutics, including recombinant therapeutic proteins like monoclonal antibodies, cytokines and tissue growth factors. Although the pharmacokinetics of therapeutic biologics should be evaluated based on the same general principles as small molecules, careful considerations should be given to bioanalytics and pharmacokinetics when designing pharmacokinetic studies of biologics during their drug development, due to their different physicochemical properties compared with small molecules. The aim of this study was to develop a draft guidance on pharmacokinetic studies of therapeutic biologics in clinical studies. All the elements outlined in the current Food and Drug Administration (FDA), European Medicinal Agency (EMEA), and International Conference on Harmonisation (ICH) guidelines and regulations, and the related literatures previously published were searched and evaluated. In this draft guidance, the specific problems related to the pharmacokinetics of therapeutic biologics that need special consideration during drug development process were addressed, and differences in pharmacokinetic characteristics between biologics and small molecules affecting the content of the development programme were presented.

• Journal of Ginseng Research
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• v.43 no.3
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• pp.354-360
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• 2019

Ginsenosides, the major active ingredients of ginseng and other plants of the genus Panax, have been used as natural medicines in the East for a long time; in addition, their popularity in the West has increased owing to their various beneficial pharmacological effects. There is therefore a wealth of literature regarding the pharmacological effects of ginsenosides. In contrast, there are few comprehensive studies that investigate their pharmacokinetic behaviors. This is because ginseng contains the complicated mixture of herbal materials as well as thousands of constituents with complex chemical properties, and ginsenosides undergo multiple biotransformation processes after administration. This is a significant issue as pharmacokinetic studies provide crucial data regarding the efficacy and safety of compounds. Moreover, there have been many difficulties in the development of the optimal dosage regimens of ginsenosides and the evaluation of their interactions with other drugs. Therefore, this review details the pharmacokinetic properties and profiles of ginsenosides determined in various animal models administered through different routes of administration. Such information is valuable for designing specialized delivery systems and determining optimal dosing strategies for ginsenosides.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.4
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• pp.670-677
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• 2020

Objective: Interleukin-6 (IL-6) is a T cell-derived B cell stimulating factor which plays an important role in inflammatory diseases. In this study, the pharmacokinetic properties of LMT-28 including physicochemical property, in vitro liver microsomal stability and an in vivo pharmacokinetic study using BALB/c mice were characterized. Methods: LMT-28 has been synthesized and is being developed as a novel therapeutic IL-6 inhibitor. The physicochemical properties and in vitro pharmacokinetic profiles such as liver microsomal stability and Madin-Darby canine kidney (MDCK) cell permeability assay were examined. For in vivo pharmacokinetic studies, pharmacokinetic parameters using BALB/c mice were calculated. Results: The logarithm of the partition coefficient value (LogP; 3.65) and the apparent permeability coefficient values (P_app; 9.7×10^-6 cm/s) showed that LMT-28 possesses a moderate-high cell permeability property across MDCK cell monolayers. The plasma protein binding rate of LMT-28 was 92.4% and mostly bound to serum albumin. The metabolic half-life (t_1/2) values of LMT-28 were 15.3 min for rat and 21.9 min for human at the concentration 1 μM. The area under the plasma drug concentration-time curve and C_max after oral administration (5 mg/kg) of LMT-28 were 302±209 h·ng/mL and 137±100 ng/mL, respectively. Conclusion: These data suggest that LMT-28 may have good physicochemical and pharmacokinetic properties and may be a novel oral drug candidate as the first synthetic IL-6 inhibitor to ameliorate mammalian inflammation.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.878-880
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• 2004

Revered-phase LC-electrospray ionization mass spectrometry was used to selectively determine enalapril from plasma with minimal sample preparation. Detection limit of the method was 1 ng/mL. Precision (within day and between days) and accuracy of the method at various concentrations were acceptable. The analytical technique was used for pharmacokinetic studies after administration of enalapril to human test subjects.

• Journal of Pharmaceutical Investigation
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• v.21 no.2
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• pp.85-90
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• 1991

Prodrugs of flurbiprofen, 1,2-ethanediolester(FE) and 1,4-butanediolester(FB) were prepared and their biopharmaceutical studies were performed. The prodrugs showed high stability in simulated gastric fluid, simulated intestinal fluid and pancreatin-saturated solution. Pharmacokinetic parameters of the prodrugs were similar to those of their parent drug. However they showed less acute toxicity and gastric irritation and higher anti-inflammatory and analgesic effects.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2631-2636
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• 2009

JHL45, a novel immune modulator for anti-atopic dermatitis and allergic airway disease, was synthesized from decursin isolated from Angelica gigas. In order to conduct a pharmacokinetic study of JHL45, an analytical method, ideally one that uses a minimal amount of biological sample must first be validated. In this study, a HPLC-MS/MS method was developed and validated for the quantification of JHL45 and its major metabolite, (+)-decursinol, from 10 ${\mu}L$ of rat plasma. JHL45 was stable under the analysis conditions, and intra- and inter-day accuracies exceeded 90.06%, with a precision variability ${\leq}$ 13.16% for each analyte. The mean values for Cmax, AUC8h, half-life of JHL45 in rats after intravenous administration of 5 mg/kg JHL45 were 24.59 μg/mL, 10.02 ${\mu}g{\cdot}h/mL$, and 1.88 h, respectively. The validated method herein will be useful for further pharmacokinetic studies of JHL45, as well as in preclinical and clinical phases.