• Journal of Pharmaceutical Investigation
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• v.34 no.4
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• pp.283-288
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• 2004

The pharmacokinetics of nifedipine was studied after oral coadministration of nifedipine (5 mg/kg) with quercetin (1.5, 7.5, 15 and 30 mg/kg, respectively) and 0.5 h or 3days pretreatment with quercetin (1.5 and 7.5mg/kg) in rabbits. Pretreatment of quercetin significantly (p<0.05, at 0.5 h; p<0.01, at 3 days) increased the plasma concentration of nifedipine, but not significant in coadministraiton. The area under the plasma concentration-time curve (AUC) and the peak concentration $(C_{max})$ of nifedipine pretreated with quercetin were increased significantly (p<0.05, at 0.5 h; p<0.01, at 3 days) compared to the control. By coadministration of quercetin, only 7.5 mg/kg of quercetin increased plasma AUC and $C_{max}$ of nifedipine significantly (p<0.05) compared to the control. Plasma AUC of intravenous nifedipine (1 mg/kg) is $4235\;{\pm}\;1192\;ng/ml{\cdot}hr$. Pretreatment of quercetin significantly (p<0.05, at 0.5 h; p<0.01, at 3 days) increased the absolute bioavailability (AB%) of nifedipine to 23.9-29.2% compared to the control (17.8%). Coadministration of quercetin showed no significant effect on the AB% of nifedipine except for 7.5 mg/kg. It is suggested that quercetin alters disposition of nifedipine by inhibition of P-glycoprotein efflux pump and its first-pass metabolism. The dosage of nifedipine should be adjusted when it is administered chronically with quercetin in a clinical situation.

• Journal of Pharmaceutical Investigation
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• v.19 no.3
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• pp.163-171
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• 1989

To investigate the protein binding characteristics of cephalothin, the effects of ionic strength, pH and temperature on the binding of cephalothin to bovine serum albumin (BSA) were studied by UV difference spectrophotometric method. With increasing ionic strength at constant PH and temperature, association constant decreased, but the number of binding sites sites was about 2 constantly. It may be deduced that the binding process is not only due to electrostatic forces. And the increased association constant at high ionic strength is explained by conformational changes of BSA from complex to subunits. The pH effect on the affinity of interaction indicated that the binding affinity of drug is higher in the neutral region than in the alkaline region. And, at high pH value, the number of binding sites decreased from 2 to 1 because of the conformational changes of BSA in alkaline region. The decrease in binding affinity of BSA to drug with increasing temperature was characteristic of an exothermic reaction. And the negative sign of ${\Delta}G^{\circ}$ meant that the binding process occurs spontaneously under the experimental conditions. In cephalothin-BSA complex formation, since the net enthalpy change value and entropy change value are positive, it is assumed that hydrophobic bindings are predominant in this binding process.

• Biomolecules & Therapeutics
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• v.8 no.3
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• pp.276-280
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• 2000

In order to identify the domains of the G$_{\alpha}$16 subunit G protein that are responsible for its activation by the Interleukin-8 receptor, a serious of chimeras between G$_{\alpha}$16 and G$_{\alpha}$11 were assessed for their abilities to be activated by these receptors. Co-expression of IL-8 receptor and chimeras in which the carboxyl-terminal regions of G$_{\alpha}$11 were replaced from 30 up to 156 amino acid residues with the corresponding regions of G$_{\alpha}$16 demonstrated that C-terminal 156 amino acid residues of the G$_{\alpha}$16 were not sufficient to confer IL-8 receptor interaction specificity. Testing of a reciprocal serious of chimeras composed of G$_{\alpha}$16 sequences at the amino terminus and G$_{\alpha}$11 sequences at the carboxyl terminals revealed that sequences extending from the amino tar- minus to amino acid 209 of G$_{\alpha}$16 were sufficient to 7ndow the chimera with 75-80% of interaction specificity for 7-8-induced activation. These results suggest th,.7t combined interactions of the C-terminal 30 amino acid residues and certain domains extending from the arts.ino terminus to amino acid 209 of Gal 6 protein may be involved in its couplings to IL-8 receptor.tain domains extending from the arts.ino terminus to amino acid 209 of Gal 6 protein may be involved in its couplings to IL-8 receptor.

• Journal of the Korea Convergence Society
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• v.9 no.12
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• pp.207-216
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• 2018

In Korea, there has been no national research on the use of antipsychotics for people with intellectual disabilities(I.D); therefore, it is difficult to identify the problems or to find solutions for problems in using antipsychotics. So, the purpose of this study analyze research findings on the use of antipsychotics for people with I.D in Japan. This research method compared and analyzed the results of research published in the journal J-STAGE and Medical Online and studied a cohort results using data. The results of the analysis are as follows. First, many antipsychotic drugs are prescribed to people with I.D, but it is difficult to accurately assess the effectiveness of the treatments. Second, it is not easy to detect side effects. Third, the potential side effects of drug interactions have been raised. The results was emphasized the need of research that accurately evaluate the drugs in survey of actual situation to ensure more safe use of antipsychotics to peoples with I.D in Korea.

• Korean Journal of Clinical Pharmacy
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• v.30 no.1
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• pp.31-35
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• 2020

Objective: The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are frequently prescribed medications worldwide for the treatment of hypercholesterolemia. Statins are considered to be well tolerated; however, they have a potential for myotoxicity. Concomitant drugs that inhibit cytochrome P450 3A4 can increase the concentration of statins and thus the risk of developing myotoxicity. The purpose of this study was to evaluate risk factors associated with potential drug-drug interactions in patients receiving statins. Methods: The subjects of this study were patients aged more than 18 years who received at least one prescription of statins in a general hospital located in Chuncheon-si, Korea, between January 1, 2018, and March 31, 2018. Data regarding statin use and baseline characteristics was collected from the computerized hospital database. Logistic regression analysis was used to identify risk factors associated with potential drug-drug interactions. Results: A total of 1061 patients were finally included in the study. The incidence of potential drug-drug interactions was 45% in all subjects. According to the results of the multivariate logistic regression analysis, myocardial infarction as the indication of statin, arrhythmia or heart failure as a comorbidity, and aspartate aminotransferase levels higher than 40 IU/L were significant risk factors for potential drug-drug interactions in study subjects. Diltiazem was the most commonly co-prescribed drug that caused potential drug-drug interactions with statins. Conclusion: There was a considerable rate of potential drug-drug interactions in patients receiving statins. Health care professionals should attempt to reduce potential drug-drug interactions during statin administration.

• KSBB Journal
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• v.24 no.6
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• pp.533-540
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• 2009

In this work, 5'-nitroindirubinoxime (5'-NIO) has been prepared as solid dispersions using a supercritical aerosol solvent extraction system (ASES) process in order to enhance its water solubility and dissolution rate. Solid dispersions of 5'-NIO and poly(vinyl pyrrolidone) (PVP) were prepared in various weight percent ratios. Three-component solid dispersions consisting of 5'-NIO, PVP, and poloxamer 188 (P188) were also prepared to study the influence of P188 level on their morphology, crystallinity, and dissolution behavior. All samples were prepared at $35^{\circ}C$ and 180 bar using supercritical carbon dioxide. The particle morphology and size of the two-component solid dispersions were found to be nearly spherical and much smaller (100-200 nm) compared with the original 5'-NIO. The morphology of three-component solid dispersions became more agglomerated as the level of P188 increased. The crystallinity of the original 5'-NIO was not observed in the solid dispersions prepared by the ASES process. Faster dissolution rates were observed for the three-componet solid dispersions because the arrangement of ethylene oxide and propylene oxide blocks of the poloxamer 188 enabled the formation of micelles in an aqueous phase.

• Korean Journal of Clinical Pharmacy
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• v.21 no.2
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• pp.90-99
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• 2011

Health Insurance Review & Assessment Service (HIRA) claims database has a high potential to detect signals of new drug interactions. The aim of this study was to evaluate the usefulness of information component (IC) and relative risk (RR) as a tool for signal detection, and to analyze the possible drug interactions caused by clopidogrel using HIRA claims database. This study was performed in elderly patients over 65 years of age who administered clopidogrel from January 2005 to June 2006 in South Korea. Serious Adverse Events (SAEs) as drug interactions of clopidogrel were defined as any ambulatory hospitalization for ischemic diseases within comcomitant medication period of clopidogrel. Information Component (IC) and Relative Risk (RR) were calculated to compare the proportion of drug-SAE pairs in order to select drug specific SAEs. IC and RR signals of clopidogrel drug interaction were screened when IC's 95% confidence interval was greater than 0 and RR's 95% confidence interval was greater than 1 respectively. All detected signals were compared to references such as $Micromedex^{(R)}$ and 2010 Drug Interaction $Facts^{TM}$. Sensitivity, specificity, positive predicted value and negative predicted value were used to evaluate usefulness of this method. Among 13,252,930 cases of elderly patients who co-administered clopidogrel and other drugs, 47,485 cases were detected as SAE. Of these, one-hundred nine cases were detected by the IC-based data-mining approach and ninety one cases were detected by the RR-based data-mining approach. Total One-hundred sixty three unrecognized signals were detected by IC or RR. Twelve signals from IC-based data-mining (57.1%) were corresponded with drug interactions from references and eight signals from RR-based data-mining (38.1%) were corresponded with drug interactions from references. These signals include proton pump inhibitors, calcium channel blockers and HMG CoA reductase Inhibitors, which were known to affect CYP450 metabolism. Further studies using HIRA claims database are necessary to develop appropriate data-mining measure.

• Journal of Yeungnam Medical Science
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• v.24 no.1
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• pp.1-10
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• 2007

The chronic fatigue immune dysfunction syndrome (abbreviated CFIDS or CFS) is a disorder characterized by debilitating fatigue(over 6 months.), along with cognitive, musculoskeletal, and sleep abnormalities. The etiology of this illness is unlikely to be a single agent. Findings to date suggest that physiological and psychological factors work together to predispose and perpetuate the illness. Diagnosis is made difficult by the nonspecific clinical findings and no available diagnostic testing. With no known cause or cure for the chronic fatigue and immune dysfunction syndrome, treatment is based on relieving symptoms and improving the quality of life of affected patients. There is emerging evidence that chronic fatigue syndrome may be familial. In the future, studies will examine the extent to which genetic and environmental factors play a role in the development of chronic fatigue syndrome. Most patients with CFS have psychiatric problems such as a generalized anxiety disorder, or major or minor depression, therefore, these mental health disorders may be correlated with the pathophysiology of the CFS. The treatment for CFS must be individualized, due to the heterogeneity of the CFS population. Also the treatment of CFS is built on a foundation of patient-physician relationship, respect and advocacy.

• Korean Journal of Clinical Pharmacy
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• v.19 no.1
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• pp.1-17
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• 2009

Adverse drug reactions (ADR) caused by inappropriate prescription are responsible for major socioeconomic loss. Drug-drug interactions (DDI) has been recognized as a major part of ADRs and, therefore, healthcare professionals should prevent possible DDIs to minimize preventable ADRs. This study aimed to examine DDI information in drug information references and Korea Food & Drug Administration (KFDA) drug labeling information. Drug ingredients from the formulary of Health Insurance Review and Assessment Service in Korea (HIRA) were included for the study. DDI information source used for the study were Micromedex Drugdex and Drug Information Facts (DIF) with the DDI severity level of "moderate" or more. The DDI information in KFDA drug labeling were collected and compared. Drug ingredients were classified with KFDA Drug Classification and ATC Classification of WHO for the analysis. Among the total 1,355 drug ingredients satisfying inclusion criteria, 738 ingredients involved at least one DDI, which was described in Micromedex and/or DIF. Drug Ingredients of 176 involved DDI only described in KFDA drug labeling, but not Micromedex nor DIF. Drug ingredients of 35 which DDIs were described in Micromedex or DIF did not have DDI based on KFDA drug labeling. Micromedex and DIF retrieved 7,582 and 3,071 DDIs, respectively 57.6% and 58.5% of DDIs were also described in KFDA drug labeling. Central nervous system (CNS) drugs, cardiovascular system (CVS) drugs and the antiinfectives appeared to have higher frequency of DDIs among all drug classes. The highest number of DDIs with high severity level ("contraindicated" or "major") were the DDIs of CNS drugs. The antiinfectives are the second drug group having serious DDIs. The DDI pairs of the CNS drug and the antiinfective had the highest contraindication risk (13.6%). DDI information from Micromedex and DIF were not consistent with the result that only 465 ingredients' DDIs are common in both literature (total DDI numbers were 715 vs 488, respectively). And 1,652 DDI information are common in both references among 7,582 vs 3,071 DDIs, respectively. Only 55.2% of DDI information in the database contained in the KFDA drug labeling. Prescribers and pharmacists should pay attention to the drugs for CV system, CNS and infections because of higher risk of possible DDIs compared to other drug classes. KFDA drug labeling is not likely to be recommended as a good information source for DDI due to significant inconsistency of information. Drug information providers should be aware that DDI information from different sources are not consistent and therefore multiple references should be used.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.509-515
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• 2021

In this study, poly lactic-co-glycolic acid (PLGA) nanoparticles (PNP) were prepared through double (w/o/w) emlusion and emulsifying solvent-evaporation technique using PLGA, which has biocompatibility and biodegradability. To maximize stability and bioavailability of the particles, chitosan-coated PLGA nanoparticles (CPNP) were prepared by charge interaction between PNP and chitosan. We demonstrated that CPNP can be utilized as a drug carrier of oral administration. The chemical structure of CPNP was analyzed by ¹H-NMR and FT-IR, and all characteristic peaks appeared, confirming that it was successfully prepared. In addition, particle size and zeta potential of CPNP were analyzed using dynamic light scattering (DLS) while morphological images were obtained using transmission electron microscope (TEM). Thermal decomposition behavior of CPNP was observed through thermogravimetric analysis (TGA). In addition, the cytotoxicity of CPNP was confirmed by MTT assay at HEK293 and L929 cell lines, and it was proved that there is no toxicity confirmed by the cell viability of above 70% at all concentrations. These results suggest that the CPNP developed in this study may be used as an oral drug delivery carrier.