• Title/Summary/Keyword: slow-release

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Effect of Solvent in Human Hair Dyeing with Natural Dye (I) (천연염료에 의한 모발염색에서 용매의 효과 (I))

  • Yang, Hye-Youn;Jang, Mi-Hwa;Kim, Sung-Min;Choi, Chang-Nam
    • Textile Coloration and Finishing
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    • v.21 no.2
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    • pp.22-28
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    • 2009
  • Human hair is a kind of fibrous keratin which has much cystine residues like wool fiber. It protects human head from the dangerous shock and is an organ to release heavy metals in human body. Recently, in many dyeing field there is a trend to utilize the natural dyes. Cochineal is a reddish natural mordant dye. When the cochineal is applied in human hair dyeing, it is expected that dyeing rate will be slow and wash fastness will be poor on account of large molecular weight relative to oxidative dyes. In this work, we investigated the effects of tributyl phosphate in hair dyeing with natural dye cochineal. Dyeability of hair increased significantly by adding tributyl phosphate in cochineal dyeing. Nevertheless the hair was slightly damaged during dyeing, the dyed hair showed a good wash fastness.

Respiratory Depression during Oral MS-Contin Administration for Pain Management of Gall Bladder Cancer (말기 담낭암 환자의 통증조절을 위해 MS Contin 투여중 발생한 호흡억제 -증례 보고-)

  • Lee, Chul-Woo;Lee, Byung-Ho;Lee, Yong-Hee
    • The Korean Journal of Pain
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    • v.9 no.1
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    • pp.239-243
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    • 1996
  • MS-Contin is an oral controlled-release preparation of morphine sulfate that has been used widely in the management of advanced cancer pain. It prolongs plasma concentration of morphine with no observable accumulation properties following repeated dosing, thereby promoting uninterrupted sleep and hopefully improving patient's quality of life. The common side effects of MS Contin are nausea, vomiting, drowsiness and constipation. But these symptoms are usually mild and respiratory depression is a rare problem. We experienced respiratory depression during oral administration of MS contin for the pain management of advanced gall bladder cancer of 76 years old male patient with metastasis at liver, intestine and cervical lymph node. After we increased the dosage of MS Contin from 160mg to 220mg per day, due to abdominal pain, we observed morphine reaction of MS Contin overdose such as pinpoint pupil, deeply slow respiration below 8/minute, and drowsiness. After intravenous bolus injection of 0.4 mg naloxone followed by continuous administration of 0.2 mg/hr for 4 hours, the patient regained consciousness. The administered route of morphine was changed to intravenous PCA (patient controlled analgesia). There was no aspiration sign as confirmed by chest x-ray. The patient was comfortable and delayed no signs of respiratory depression until now.

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Nitric-Acid Pulping of Municipal Wastepapers and its Spent-Liquor Utilization for Fertilizers(I) -Study on the Nitric-Acid Pulping Conditions of OCC Pulp- (도시 폐휴지의 질산 펄프제조와 펄프폐액의 입상 비료화 기술개발(I) -폐골판지 상자(OCC)의 질산 펄프제조 조건-)

  • 임기표;위승곤;김창래;양정훈
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.32 no.4
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    • pp.74-80
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    • 2000
  • A series of studies on nitric-acid pulping of municipal recycled waste papers were carried out to substitute the bleached chemical pulp imported for producing printing paper as well as to use its solidified spent-liquor as fertilizer. The first experiment was carried out to find the optimum treatment conditions such as pulp consistency, nitric acid charge and temperature in $HNO_3$-alkali pulping process. The results obtained were as follows: 1. Some selective delignification of OCC pulp was conducted by $HNO_3$-alkali process. The higher the temperature and concentration of nitric acid, the lower the pulp yield and kappa number of treated pulp. while its brightness was increased. 2. The higher consistency required the stronger mixing in case of more than 5% pulp. 3. In the laboratory, the suitable $HNO_3$-treating condition seemed to be less than 6% consistency, lower than 500% $HNO_3$charge on pulp and lower than $100^{\circ}C$ in cooking temperature. 4. The spent liquor with 1.77% N-content seemed to be slow-release nitrogen fertilizer suitable for agriculture.

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Novel Fabrication of CdS Hollow Spheres Induced by Self-assembled Process

  • Choi, Kyoung-Hoon;Chae, Weon-Sik;Jung, Jin-Seung;Kim, Yong-Rok
    • Bulletin of the Korean Chemical Society
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    • v.30 no.5
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    • pp.1118-1120
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    • 2009
  • Micro-size CdS spheres of hollow shape were fabricated through the self-assembly of high density arrow-like nanorods. The synthesis of the CdS hollow spheres were accomplished in an aqueous solution of cadmium nitrate and triblock copolymer (Pluronic P123) at low temperature (80 ${^{\circ}C}$) through the slow release of S2- ions from thioacetamide. Morphology of the fabricated CdS hollow spheres was characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). The results indicate that the arrow-like CdS nanorods are simultaneously grown and attached each other to form the building units that become the spheres with hollow inside as a self-assembled process. The CdS spheres have a diameter of $2{\sim}3 {\mu}m$ and consist of the nanorods with a length of$\sim$800 nm. The nanocrystal building blocks have a hexagonal CdS structure.

Effects of $\alpha$-Adrenoceptor Antagonists on Phenylephrine-induced Contraction in the Endothelium-denuded Rat Aorta (내피세포를 제거한 흰쥐 대동맥에서 Phenylephrine이 일으킨 수축반응에 대한 $\alpha$-수용체 길항제의 영향)

  • 홍승철;강맹희;박상일;박미선;최수경;정준기;서석수
    • YAKHAK HOEJI
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    • v.35 no.5
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    • pp.416-426
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    • 1991
  • The effects of an irreversible or a reversible $\alpha_1$-adrenoceptor antagonist (dibenamine or prazosin) on $\alpha_1$-adrenoceptor-mediated vasoconstrictions were studied in the endothelium-denuded rat aorta. In these experiments, the mobilization of intracelluier calcium and translocation of extracellular calcium were also studied. To exclude the modulation of endothelium releasing EDRF and EDCF, the endothelium was removed in all rat aortas. Contraction induced by phenylephrine (a full $\alpha_1$-adrenoceptor agonist) was separated into a fast phasic component of the response due to the release of intracellular calcium and a slow tonic one due to the influx of extracellular calcium. Pretreatments with increasing doses of reversible $\alpha_1$-adrenoceptor antagonist prazosin, as well as irreversible $\alpha_1$-adrenoceptor antagonist dibenamine, inhibited the phasic component of phenylephrine-induced contraction more effectively than the tonic one. Pretreatment of dibenamine (0.2 $\mu{M}$) or prazosin (10 nM) to the rat aorta abolished phasic response but remained tonic one about 41% and 51%, respectively. These results suggest that as the efficiency of phenylephrine was progressively reduced by pretreatments with increasing doses of an irreversible or a reversible $\alpha_1$-adrenoceptor antagonist (dibenamine or prazosin), the contraction induced by phenylephrine became progressively more dependent on the influx of extracellular calcium.

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Characteristics of Heavy Metal Releases from the Abandoned Dogog Mine Tailing in Korea (도곡광산 광미의 중금속 용출 특성)

  • Park, Chang-Jin;Kim, Won-Il;Jeong, Goo-Bok;Lee, Jong-Sik;Ryu, Jong-Su;Yang, Jae-E.
    • Korean Journal of Environmental Agriculture
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    • v.25 no.4
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    • pp.316-322
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    • 2006
  • Objective of this research was to assess the release characteristics of metals from the mine tailing to base the prediction of metal load potential from tailing to soils. Water-soluble concentrations of Cd, Cu, Pb and Zn released from mine tailing after 2 hrs were 2.31, 129.38, 17.17, and 287.53 mg/kg, respectively, as compared to 1.6, 128, 108, and 142 mg/kg that were extractable by 0.1 M HCl. Kinetics of metal releases followed the power function model significantly indicating that more of water soluble fractions of those metals released at the initial short time, followed by a slow increase. Concentrations of metals released from tailing by water and 0.1 M HCl were in the orders of Zn > Cu > Pb > Cd. The breakthrough curve from the column experiment showed that concentrations of Cd, Cu, and Zn reached at highest after one pore volume, but that of Pb reached highest after five pore volumes when 0.1 M HCl was used as eluent. The release rate of Cd from mine tailing was the fastest but Pb was the slowest. The cumulative mass of metal released by 0.1 M HCl was in the order of Zn > Cu > Pb > Cd after nine pore volume elution.

MONOMER RELEASE FROM PIT AND FISSURE SEALANT FOLLOWING BY SURFACE TREATMENT AND CURING TIME (치면열구전색제의 표면처리와 중합시간 증가에 따른 미반응 모노머 용리 평가)

  • Seo, Hyun-Woo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.34 no.1
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    • pp.122-129
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    • 2007
  • The purpose of this study was to evaluate the effects of a various light curing time on the residual monomers released from light-cured dental sealant, and to examine the effectiveness of surface treatment in reducing the oxygen-inhibited layer of light-cured dental sealant($Helioseal^{(R)}$ F, Vivadent, Liechtenstein). Specimens were cured with a halogen light curing unit(XL 3000, 3M, USA) for 20, 40, 60s. Surface treatment of a light-cured dental sealant included no treatment(control group), a 10-seconds exposure to distilled water(Group I), 10-seconds manual application using a cotton pellet wetted with 75% alcohol(Group II), and 10-seconds application of a water/pumice slurry using a rubber cup on a slow-speed handpiece The specimens were eluted in distilled water for 10 minutes. All elutes were analyzed by HPLC for identification and quantitive analysis of monomers. The results of this study can be summarized as follows. 1. None of the chromatograms of the tested sealant displayed peaks with the same retention time as that of the standard solution, except for TEGDMA. 2. The release of TEGDMA decreased with increasing curing time in conventional halogen light. 3. All surface treatment group had a decrease of monomer release in comparison with no treatment group. 4. Treatment that Group III eliminated the greatest amount of any type of residual monomers. 5. The elution of unreacted monomers from curing with halogen curing unit for 60s and Group III was less than other groups.

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Preparation and Characterization of Deoxycholic Acid-Conjugated Low Molecular Weight Water-Soluble Chitosan Nanoparticles for Hydrophobic Antifungal Agent Carrier (소수성 항진균제 전달체로 응용하기 위한 데옥시콜릭산이 결합된 저분자량 수용성 키토산 나노입자의 제조와 특성)

  • Choi, Chang-Yong;Jung, Hyun;Nam, Joung-Pyo;Park, Yoon-Kyung;Jang, Mi-Kyeong;Nah, Jae-Woon
    • Polymer(Korea)
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    • v.33 no.4
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    • pp.389-395
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    • 2009
  • To develop the carrier of hydrophobic antifungal agents based on low molecular weight water-soluble chitosan (LMWSC), LMWSC was chemically modified with deoxycholic acid (DA) which is one of the bile acid as a hydrophobic group. The nanoparticles (WSCDA) using DA conjugated LMWSC were characterized using dynamic light scattering (DLS) and transmittance electron microscope (TEM). The particle size of WSCDA ranged from 250 to 350 nm and increased with the number of DA substitution. The loaded itraconazole as an antifungal agent WSCDA nanoparticles (WSCDA-ITCN) were prepared by solvent evaporation method. The drug content and the loading efficiency were investigated approximately $9{\sim}10%$ and $61{\sim}68%$ by UV spectrophotometer, respectively. The release of drug from nanoparticles was slow and showed sustained release characteristics. Based on the results of release study that the higher DA contents in WSCDA, the slower the releasing rate, the WSCDA-ITCN could be used as an excellent antifungal agent.

Inhibition of Intimal Hyperplasia by Perivascular Delivery of Paclitaxel Using Poly(n-butylmethacrylate) or Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) in Balloon-Injured Rat Carotid Arteries (쥐 경동맥 손상 모델에서 Poly(n-butylmethacrylate) 혹은 Poly(3-hydroxybutyrate-co-4-hydroxybutyrate)를 이용한 Paclitaxel 국소 전달 요법의 신생내막 형성 억제 효과)

  • Kwon, Jin-Sook;Lee, Ho-Yeon;Heo, Shin-Haeng;Park, Rho-Kwan;Shim, Tae-Jin;Kim, Yu-Kyug;Kim, Beom-Soo;Kim, Dong-Woon
    • Polymer(Korea)
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    • v.32 no.3
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    • pp.284-289
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    • 2008
  • Polymer is a critical component of local drug delivery to prevent restenosis. This study tested whether poly(n-butylmethacrylate)(PBMA) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(PHA) was candidates for this purpose. In vitro release of paclitaxel from PBMA and PHA loaded with 10% paclitaxel exhibited a triphasic release profile, with a fast initial and intermediate second phase followed by a slow release phase. Perivascular delivery of paclitaxel using these films inhibited neointimal hyperplasia in balloon-injured rat carotid arteries. The paclitaxel-loaded PBMA or PHA groups showed significant neointimal formation reductions versus the control groups (PBMA vs control: $0.03{\pm}0.02$ vs $0.10{\pm}0.01\;mm^2$, p<0.05; PHA vs control: $0.04{\pm}0.03$ vs $0.09{\pm}0.01\;mm^2$, p<0.05). This study suggests that PBMA and PHA could be good candidate polymers of local drug delivery to prevent restenosis. Perivascular delivery using these films represents a possible approach for prevention of restenosis. These can be candidate polymers for drug eluting stents.

Effect of Cosurfactants on the Release Behavior of Zaltoprofen-loaded PLGA Microspheres in In Vitro : Preparation and Characterization (보조계면활성제 첨가에 따른 잘토프로펜을 함유한 PLGA 미립구의 생체외 방출 거동: 제조 및 특성)

  • Eom, Shin;Yoo, Seok-Cheol;Kim, Yong-Ki;Lee, Young-Hyun;Lee, Eun-Yong;Yu, Hyeon;Lee, Dong-Won;Khang, Gil-Son
    • Polymer(Korea)
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    • v.34 no.4
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    • pp.333-340
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    • 2010
  • Zaltoprofen, a propionic acid derivative non-steroidal anti-inflammatory drug (NSAID), is known to have powerful inhibitory effects on acute, subacute and chronic inflammation. We developed poly(lactide-co-glycolide)(PLGA) microspheres loaded with zaltoprofen for sustained controlled delivery using an oil-water solvent evaporation methods by varying PLGA molecular weight and cosurfactant contents. Physicochemical properties and morphology of zaltoprofen-loaded PLGA microspheres were investigated by scanning electron microscope, X-ray diffraction and differential scanning calorimeter. The size of microspheres increased with the molecular weight of PLGA and the content of cosurfactants. The increase of PLGA molecular weight and cosurfactant content decreased the porosity of microspheres, subsequently resulting in the slow drug release. The results demonstrated that the adjustment of PLGA molecular weight and the cosurfactant content allowed us to control the drug release profiles of drug-loaded microspheres.