• Journal of Pharmaceutical Investigation
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• 제23권4호
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• pp.213-216
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• 1993

${\kappa}-Carrageenan$, an anionic polysaccharide, was employed in tablet formulations and its function as a drug release sustaining agent was investigated. Tablets composed of ${\kappa}-carrageenan$ and hydroxypropyl methylcellulose were fabricated by using direct compression method. Lactose and sodium alginate were utilized as controls for ${\kappa}-carrageenan$. Drug release experiments performed at pHs 1.2 and 7.4 revealed that ${\kappa}-carrageenan$ retains pH-dependent sustained release effects due to its anionic characteristics. Also, the ionic interaction between ${\kappa}-carrageenan$ and drugs exerted significant affects on drug release kinetics. ${\kappa}-Carrageenan$ was found out to be a useful additive for sustained release tablet formulations.

• 대한한방내과학회지
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• 제25권2호
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• pp.238-244
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• 2004

Objective : This study is intended to investigate whether the two oriental medical prescriptions, CheongGeumGangHwa-tang(CGGH) and GwaRuJiSil-tang(GRJS), significantly affect mucin release from cultured hamster tracheal surface epithelial(HTSE) cells. Materials and Methods : Confluent HTSE cells were metabolically radio labeled with 3H-glucosamine for 24 hrs and chased for 30 min in the presence of CGGH or GRJS to assess the effect of each agent on 3H-mucin release. Possible cytotoxicities of each agent were assessed by measuring lactate dehydrogenase(LDH) release. Also, the effects of CGGH and GRJS on contractility of isolated tracheal smooth muscle were investigated. Results : (1) CGGH and GRJS significantly increased mucin release from cultured HTSE cells, without cytotoxicity : (2) CGGH and GRJS did not affect contractility of isolated tracheal smooth muscle. Conclusions : These results suggest that the effects of CGGH and GRJS should be further investigated, and that it would be gainful to invesigate, from among oriental medical prescriptions, what novel agents have these mild expectorant effects on mucin secretion from airway goblet cells.

• Journal of Pharmaceutical Investigation
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• 제40권3호
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• pp.181-185
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• 2010

The objective of this study was to improve the extent of drug release as well as the dissolution rate of TD49, a novel algicidal agent, via the preparation of solid dispersion (SD). Among the various carriers tested, $Solutol^{(R)}$ HS15 was most effective to enhance the solubility of TD49. Subsequently, SDs of TD49 were prepared by using $Solutol^{(R)}$ HS15 and their solubility, dissolution characteristics and drug crystallinity were examined at various drug-carrier ratios. Solubili ty of TD49 was increased significantly in accordance with increasing the ratio of $Solutol^{(R)}$ HS15 in SDs. Compared to untreated powders and physical mixtures (PMs), SDs facilitated the faster and greater extent of drug release in water. Particularly, SD having the drug-carrier ratio of 1:20 exhibited approximately 90% of drug release within 1 hr. Differential scanning calorimetry (DSC) thermograms and X-ray diffraction (XRD) patterns suggested that SDs might enhance the dissolution of TD49 by changing the drug crystallinity to an amorphous form in addition to the increased solubilization of drug in the presence of $Solutol^{(R)}$ HS15. In conclusion, SD using $Solutol^{(R)}$ HS15 appeared to be effective to improve the extent of drug release and the dissolution rate of poorly water soluble TD49.

• Journal of Pharmaceutical Investigation
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• 제41권5호
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• pp.279-288
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• 2011

The Dexamethasone (DEX) loaded chitosan microspheres were prepared by thermal denaturation and chemical cross-linking method using a dierent concentration of glutaraldehyde as chemical cross-linking agent. The prepared microspheres were evaluated for the percentage of Drug Loading (DL), Encapsulation Efficiency (EE) and surface morphology by Scanning Electron Microscopy (SEM). DL and EE were found to be maximum range of 10.0 to 10.79 % and 58.19 to 64.73 % respectively. The SEM Photographs of the resultant microspheres exhibited fairly smooth surfaces and predominantly spherical in appearance. In addition, Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) shown that there was no interaction between the drug and polymer. In vitro and in vivo release studies revealed that the release of dexamethasone was sustained and extended up to 63 days and effectively controlled by the extent of cross-linking agent. Non-clinical parameters such as paw volume, hematological parameters like Erythrocyte Sedimentation Rate (ESR), Paced Cell Volume (PCV), Total Leucocytes Count (TLC), Hemoglobin (Hb), Differential Cell Count (DCC) were investigated in Fruend's Complete Adjuvant (FCA) induced arthritic rats. Radiology and histopathological studies were also performed in order to evaluate the therapeutic efficacy of the DEX-loaded microspheres in extenuating the rat arthritic model.

• 대한한방소아과학회지
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• 제20권1호
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• pp.93-107
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• 2006

Objective : To investigate the effectiveness of two oriental medical prescriptions named Sigoungcheongpyetang(SCPT) and Tonggyutanggamibang(TGT) for mucin release from cultured hamster tracheal surface epithelial(HTSE) cells. Method : Confluent HTSE cells were metabolically radiolabeled with $^{3}H-glucosamine$ for 24hrs and chased for 30 min in the presence of SCPT or TGT to assess the effect of each agent $^{3}H-mucin$ release. Possible cytotoxicities of each agent were assessed by measuring lactate dehy drogenase(LDH) release. Also, the effects of SCPT and TGT on contrectility of isolated tracheal smooth muscle were investigated. Results : (1) SCPT and TGT significantly increased mucin release from cultured HTSE cells, with significantly cytotoxicity ; SCPT did not affect contractility of isolated tracheal smooth muscle and TGT inhibited Ach-induced contraction of isolated tracheal smooth muscle. Conclusion : We suggest that the effects of SCPT and TGT with their components should be further investigated and it is of great value to find, from oriental medical prescriptions, novel agents which might regulate mucin secretion from airway goblet cells.

• 약학회지
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• 제41권1호
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• pp.30-37
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• 1997

In order to formulate a controlled release system for oral drug delivery, the microcapsules were prepared in w/o emulsion containing cefaclor as a water-soluble model drug by th e method of interfacial polycondensation. Gelatin wis selected as a suitable polymer for interfacial polycondensation. Gelatin solution containing drug was emulsified in an organic phase under mechanical stirring. After emulsification, terephthaloyl chloride was added as cross linking agent, followed by mechanical stirring, washing and drying. Physical characteristics of microcapsules were investigated by optical microscopy, scanning electron microscopy and particle size analysis. Mean particle sizes of gelatin microcapsules were, in the range, of about 20~50 ${\mu}$m. The microcapsules were in good apperance with spherical shapes before washing, but were destroyed partially after washing and drying, even though some microcapsules were still maintained in their shapes. Contents of cefaclor in the microcapsules were calculated by UV spectrophotometry after 3 days extraction with pH 4 carbonate buffer solution. The effects of cross linking time. pH. concentration of cross-linking agent, and temperature on drug release kinetics have been discussed extensively.

• Archives of Pharmacal Research
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• 제13권4호
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• pp.293-297
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• 1990

Sustained release microspheres containing phenylpropanolamine HCI (PPA) were prepared with acrylic polymer (Eudragit RL/RS) sand hydroxypropylmethylcellulose phthalate (HPMCP) using a emulsion-solvent evaporation method. Magnesium strate was used a smoothing agent for preparation of microspheres. The microspheres obtained were very spherical and free-flowing particles. Scanning electron microscopy showed that microspheres have a smooth surface and a sponage-like internal structure. The dissolution rate of PPA from the microspheres was dependent on the pH of dissolution media. PPA showed faster relase in hP 1. 2 solution than in pH 7.4 solution due to the solubility of PPA. Therefore we prepared new microspheres containing 5% (w/v) HPMCP in order to control the release of PPA. The release rate of PPA from these new microspheres was similar in pH 1.2 and pH 7.4 solution.

• Archives of Pharmacal Research
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• 제29권10호
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• pp.921-927
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• 2006

Prolonged release micro particles of clarithromycin (CL) were prepared using Eudragit RL 100 and RS 100 by spray-drying and casting-drying techniques. For the characterization of those microparticles, preparation yield, particle size distribution, X-ray diffraction, thermal behavior, active agent content and in vitro dissolution from the microparticles were performed. HPLC was used for the assay of clarithromycin and the assay method was validated. All the formulations obtained showed prolonged release when compared to pure clarithromycin. Microparticles prepared by spray-drying method had a slower release compared to those of casting drying method. Spray-drying method seems to be a more suitable method to prepare microparticles for prolongation in release.

• 정보처리학회논문지D
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• 제8D권5호
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• pp.623-630
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• 2001

최근 인터넷 솔루션 시장은 전자상거래의 필요성과 효과에 대한 논의를 벗어나 전자상거래 내에서의 경쟁에 초점이 맞추어져 있다. 본 논문에서는 전자상거래 시장을 활성화에 기여할 수 있는 정책지향 매칭 에이전트(policy-oriented matching agent) 시스템을 제안한다. 제안된 정책지향적 솔루션은 정책을 객체화하였기 때문에 다양한 프로모션을 구현할 수 있으며, 기존의 룰 기반 시스템의 장점에 정책이 실기되는 공간 개념(release post)을 추가하였기 때문에 정책의 수립, 실시, 추적 평가 등을 일관되게 처리할 수 있다. 정책지향 솔루션을 구현함에 있어 전자상거래를 위한 기초 플랫폼에 적합한 컴포넌트 기반 구조를 채택하고, 기존의 여타 시스템에 연동되어 마케팅 활동을 쉽게 지원할 수 있도록 한다. 또한 정책 담당자가 정책을 직관적으로 편집할 수 있는 인터페이스를 갖도록 한다.

• 한국임상약학회지
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• 제21권4호
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• pp.347-352
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• 2011

Health insurance review & Assessment service (HIRA) has enforced cutting the drug costs when physicians prescribe split extended release drugs, starting from December, 2010. The objective of this study is to analyze extended release and enteric coated drugs on pharmaceutical reimbursement list in Korea, and to investigate the impact and barriers of the health insurance review on splitting extended-release formulation drugs. By using the ingredient code, extended release and enteric coated formulations make up 7.8% of all drugs in April, 2011. The most frequently used drugs are agent affecting circulatory and digestive system. From the extended release and enteric coated formulations (n=112), 34.8% (n=39) were not available in other dosage forms. According to questionnaire survey for 169 pharmacists (response rate: 73.8%), the rate of splitting and crushing of extended release and enteric coated drugs decreased. When pharmacists correct physician's prescription errors, the biggest problem was lack of other dosage forms. So it is necessary to develop variety of other dosage forms, and computerized checking system for splitting extended-release drugs. It is also important to inform physicians and patients in regard to the problems of split prescription of extended release and enteric coated drugs.