• Economic and Environmental Geology
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• v.48 no.3
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• pp.199-204
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• 2015

In this study, we aimed to make antibiotic-intercalated smectite composites using amoxicillin and clarithromycin as hygroscopic antibiotics, and gentamicin, tobramycin and netilmicin as non-hygroscopic aminoglucosides, and to check their drug delivery potential in gastric system using preliminary in-situ column release test for clarithromycinsmectite composite. All antibiotics were successfully intercalated into the interlayer of smectite by cation-exchange reaction in the batch experiment. Equilibrium batch test showed that clarithromycin-intercalation followed Langmuir isotherm and the possible maximum amount was calculated as 1.811 mmole/g. Clarithromycin was continuously released by the solutions of pH=2, 3, and 4 and the amount was decreased with pH increase.

• Polymer(Korea)
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• v.35 no.4
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• pp.277-283
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• 2011

Solid dispersion is mainly used for improved dissolution of poorly water-soluble drugs. Solid dispersion of pranlukast was prepared by spray-drying with plasdone S-630. When pH of water was high, pranlukast was highly soluble in the solubility experiment of solid dispersions with varying pH. The particle size of pranlukast particles in solid dispersions was measured to be in nanometers scale based on particle size analysis. Zeta-potential analysis confirmed the negative charge of solid dispersion. SEM was used to observe the surface of solid dispersion, which confirmed spherical morphology, DSC and XRD confirmed the amorphous nature of solid dispersions. The in vitro test was carried out to find improved dissolution rate of pranlukast solid dispersion in simulated juice gastric and a controlled experiment was carried out to compare pranlukast solid dispersions with a conventional drug (Onon$^{(R)}$), These results showed the dissolution properties of pranlukast solid dispersions prepared by spray drying proper for the oral pharmaceutical formulation.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.126-126
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• 1995

본 연구는 중금속에 의한 생체내 독성기전을 연구하고자 흰쥐간의 상층액에서 카드뮴과 잘 결합하는 HMWP들을 분리, 정재하고 나아가 생화학적 특성을 밝히고 이단백질이 카드뮴에 의해 생성되는 것인지 아니면 간의 기존 단백질인지를 밝히고자 함을 연구의 목적으로 하였다. CdCl %2 (3mg/kg body wt.)을 3일간 ip injection시킨 후 흰쥐의 간을 적출하고 균질화하여 원심분리한 crude extract를 직접 Sephacryl S-100에 흡착시켜 10mM phosphate buffer(pH 7.0)으로 용출시켰다. 용출된 fraction tube를 UV spectrometer로 흡광도를 측정하고 atomic absorption spectrophotometer로 카드뮴량을 측정하여 카드뮴량이 높은 분획을 모아서 ion exchange column chromatography(DEAE-Sepharose)에 흡착시켜 염농도 구배로 chromatography를 실시하고, 음이온 교환수지에서 흡착되지 않고 용출된 분획을 ultrafiltration으로 농축시킨 후 S-Sepharose에 흡착시켜 염농도 구배로 chromatography를 실시한 결과 두 종류의 카드뮴 결합 단백질(Cd-BP)를 분리, 정제하였다.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.319-336
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• 2020

The purpose of this study was to compare the outcomes of two interventional methods, overlapping drug-eluting stents (DES) and long DES, for long-term clinical outcomes in patients with acute myocardial infarction (AMI). A total of 438 patients with AMI (65.9±11.0 years, 306 males) from June 2008 to March 2019 who had diffuse long coronary artery lesion, more than 30mm were divided into two groups; group I (overlapped DES group; n=140) and group II (long DES group; n=298). We compared the incidences of major adverse cardiac events [MACEs; cardiac death, myocardial infaction (MI), target lesion revascularization (TLR) and stent thrombosis (ST)] during 12 months between the two groups. Everolimus-eluting stent was more commonly used in group II than in group I (28.1% vs. 51.8% p<0.001). Mean lesion diameter was slightly longer in group II (3.1±0.3mm vs. 3.2±0.3mm, p=0.042), and prevalence of ACC/AHA lesion type C was higher in group I (41.7% vs. 25.4%, p<0.001). Incidences of MACEs during 12 months were higher in group I than group II (18.5% vs. 14.4%, p=0.034). The rates of cardiac death (2.1% vs. 4.4%, p=0.667), MI (5.0% vs. 2.7%, p=0.260) and stent thrombosis rate (0.7% vs. 1.7%, p=0.669) were similar between the two groups. However, TLR rate was higher in group I (10.7% vs. 5.6%, p=0.041). In multivariate logistic regression analysis, presence of diabetes mellitus [Hazard ratio (HR) 2.383, 95% confidence interval (CI) 1.332-4.260, p=0.003] and use of paclitaxel-eluting stent (HR) 2.367, 95% CI 1.371-4.086, p=0.002) were independent predictors of 12-month MACEs, without significant differences in prevalence between the two groups. In AMI patients with diffuse long lesion, TLR rate was higher in the overlapped DES group during 12-month follow-up. Presence of diabetes and use of paclitaxel-eluting stent were independent predictors of MACEs.

• KSBB Journal
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• v.23 no.5
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• pp.408-412
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• 2008

The rosiglitazone loaded poly (lactide-co-glycolide) (PLGA) nanoparticles (NPs) were prepared by the emulsion-evaporation method and optimized for particle size and entrapment efficiency. The optimized particles were 140-180 nm in size with narrow size distribution and 80% entrapment efficiency at 1% w/w initial drug loading when prepared with 1-3% w/v of PVA as a surfactant. These particulate carriers exhibited controlled in vitro release of rosiglitazone for 36 hrs at a nearly constant rate after 4 hrs release. In conclusion, these results indicate that PLGA NPs have greater potential for oral delivery of rosiglitazone.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.177-177
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• 1994

좌제중에서 OMZ의 분해는 1차 반응적이었으며, 안정화제로서는 arginine이 가장 좋아서 arginine을 10 mg 첨가한 Witepsol H15 좌약과 PEG 4000좌약의 분해속도 상수는 각각. 3.89$\times$10-3day$^{-1}$, 8.67$\times$$10^{-3}$ day$^{-1}$이어서, arginine 비첨가 Witepsol Hl5기제 (k = 00.11 day$^{-1}$, PEG 4000기제( k = 0.48 day$^{-1}$)의 경우보다 훨씬 양호하였으며, 35$^{\circ}C$, 75%RH에서 장기보존시험 결과 Witepsol H15 좌제와 PEG 4000 기제는 각각 k = 3.63$\times$$10^{-4}$ day$^{-1}$, t190% = 291 8 days와 k = 3.69$\times$$10^{-4}$ day$^{-1}$ 및 t90% = 282.1 days이었으며, 좌제로부터 약물의 용출에 미치는 영향은 arginine의 첨가, 원료약품 입자의 미세화, 적절한 계면활성제의 첨가 그리고 지용성 기제량의 감소등으로서 이들은 약물의 용출을 증가시켰다. 실험한 좌약의 bioavailability는 경구용 캅셀이 17%, 지용성좌제 44.9%, 수용성좌제 41.0%로서 좌제가 유의성 있게 높았으며(p<0.01), 지용성좌제에 SLS나 EDTA를 첨가하였을 때에는 각각 29.7%, 32.7%로서 이들을 첨가하지 않았을 때 보다 유의성 있게 낮았다(p<0.01). 또한 직장점막 자극시험결과 부작용을 관찰할 수 없었으며 간초회통과 회피율은 수용좌제에서 28.9%, 지용성좌제에서 33.6%로 나타나서 OMZ의 투여경로는 직장좌제가 유용한 한가지 투여방법이 될 것임을 시사하였다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.104-104
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• 1993

시방성 제제에 대한 연구는 주로 제제학적 수단에 의한 약효의 지속화로서 제제설계상 제형개발 및 투여제형에서의 약물방출 조절로 체내의 유효 혈중농도를 유지한다. 이에 약물 방출 조절용 물질의 하나로서 체내 분해가 가능하고 독성이 없는 생체 고분자인 Chitosan이 약물방출 담체로서 양호함에 착안하여 약물의 서방화를 기하고자 본 실험에 착수 하였다. 모델 약물로서는 sulfamethoxazole, acetaminophen, sylimarin을 사용하여 chitosan gel 과 혼합비를 달리하여 고형 문산체를 조제하고 이것을 formaldehyde, glutaraldehyde, 1acetaldehyde, butylaldehyde 4종의 aldehyde를 사용하여 농도에 따른 가교화가 in vitro에서의 약물용출에 미치는 영향을 검토하였으며, 또한 위장을 거쳐 소화효소 또는 장내미생물 효소에 의한 chitosan 분해로 약물 방출의 촉진을 실험한바 지견을 얻었기에 보고한다.

• Polymer(Korea)
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• v.37 no.4
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• pp.442-448
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• 2013

In this study, we developed and optimized hydrophilic polymer-based solid dispersion formulations (SDs) using a spray drying method for improving the aqueous solubility of eprosartan, one of poorly soluble drugs that has been broadly used for the treatment of high blood pressure. Hydroxylpropylcellulose (HPC) and poly(vinyl pyrrolidone) (PVP) were used as hydrophilic polymer matrices and poloxamer 407 (P407) added as a polymeric surfactant. Various kinds of solid dispersions with different drug/polymer compositions were prepared and their physico-chemical properties were compared. As the polymer content increased, the drug crystallinity in the SDs significantly decreased and the dissolution properties were enhanced. The PVP based SDs were observed to have relatively reduced crystallinity and an enhanced dissolution rate than HPC-based SDs, due to better miscibility between drug and polymer matrix. For PVP based SDs, the drug crystallinity almost disappeared and the dissolution properties significantly increased by more than 3~7 times.

• Journal of the Korean Society of Radiology
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• v.13 no.3
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• pp.381-389
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• 2019

Although the development of Drug-eluting stent (DES) improved the ISR significantly more than the Bare metal stent (BMS), the coronary stent restenosis (ISR) treatment still has a high recurrence rate. This study is compared the efficacy of DEB with that of DES implantation in patients with ISR. Among 4,316 patients who underwent coronary stent implantation at the Chonnam National University Hospital between November 2012 and December 2016, 187 patients developed ISR on follow-up coronary angiography ($66.3{\pm}11.0years$, 123 males) were enrolled and divided into two groups according to revascularization method as group I (DEB group; n=127) and group II (DES group; n=60). Primary end point was defined as major adverse cardiac events (MACEs), composite of cardiac death (CD), myocardial infaction (MI), target lesion revascularization (TLR) and stent thrombosis (ST) during two-year follow-up between the two groups. There were no differences in the baseline characteristics and angiographic findings except that prevalence of device length was shorter ($21.1{\pm}5.3$ vs. $25.3{\pm}9.6 mm$, p<0.002) in group I.Two-year MACE were not different in the two groups (8.7%vs.10.0%, p=0.789). The incidences of cardiac death (0%vs.0%, p=1.000), MI (1.6%vs.6.7%, p=0.085), TLR(8.7% vs. 10.0%, p=0.789) and ST (0% vs. 0%, p=1000). DEB demonstrated comparable risk reduction for MACEs compared with DES in patients with ISR during two-year follow-up. DEB might be good alternative for the treatment of ISR in patients with ISR.

• Polymer(Korea)
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• v.36 no.1
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• pp.41-46
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• 2012

In this study, poly(ethylene glycol) (PEG) was used as a hydrophilic polymer carrier to develop solid dispersion formulations for enhancing solubility and dissolution rate of pranlukast, one of poorly soluble drugs that has been broadly used for the treatment of asthma. PEG based solid dispersions with or without poloxamer were prepared by hot melting and solvent evaporation methods. The resultant solid dispersions were characterized by DSC and powder X-ray measurements, and their morphological properties were observed to be partially changed to amorphous state with reduced crystallinity. Dissolution and solubility tests showed that the solubility and dissolution rate of the solid dispersions were significantly enhanced. The solid dispersion formulation prepared by the hot melting method with a chemical composition of pranlukast:PEG:poloxamer = 1:5:1 demonstrated the most enhanced solubility and dissolution rate. The results suggest that the solid dispersions based on PEG and poloxamer are promising systems for the enhancement of solubility and bioavailability of pranlukast.