• Title/Summary/Keyword: release-control

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Drug Release Characteristics and Skin Irritancies of Topical Gels and Multiple Emulsion Creams Containing Kojic Acid (외용겔 및 다중유제크림의 코지산 방출특성과 피부자극성)

  • Yu, Sung-Un;Park, Eun-Woo;Choi, Young-Wook
    • Journal of Pharmaceutical Investigation
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    • v.28 no.2
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    • pp.87-92
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    • 1998
  • Kojic acid (KA) is an antimelanogenic agent which has been widely used in cosmetics to whiten the skin color. However, it has the drawbacks of the skin irritancy and the instability against the pH, temperature, and light. In order to overcome these problems, various topical gels and multiple emulsion creams which can control the release of active ingredient, KA, were formulated employing cream bases of mineral oil with caprylic capric triglyceride and hydrophilic polymers such as chitosan, carbopol. and pluronics. Using Franz diffusion cells mounted with a synthetic cellulose membrane (MWCO 12,000), drug release characteristics of the formulations were evaluated by the HPLC assay of KA concentration in the receptor compartment of pH 7.4 phosphate buffered saline solution. Drug release from chitosan-based gels (ChitoGel) obeyed to the first order kinetics with a rapid release especially in the initial period. However, pluronic-based gels (PluGel) and carbopol-based gels (CarboGel) revealed controlled release of drug to some extent, followed by the square root-time kinetics. Moreover, the release of KA was further controlled with the W/O/W multiple emulsion creams (MultiCream), showing the apparent zero order release kinetics by virtue of dynamic ratecontrolling membrane of the oil layer. The flux $(J,\;{\mu}g/cm^2/hr)$ of ChitoGel. CarboGel. PluGel. and MultiCream in the initial period of 6hr were 73.30, 28.67. 24.04 and 7.72, respectively. On the other hand, the skin irritancy score of ChitoGel and MultiCream were observed as 2.5 and 2.3 respectively, in the rabbit skin irritation test. Although there were insignificant differences at p<0.05 between those formulations, it was possible to conclude that the W/O/W multiple emulsion creams containing KA might be a good candidate for an antimelanogenic drug delivery system due to the controlled release of acidic drug molecules.

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Biological Control of Two Spotted Spider Mite (Tetranychus urticae) by the Predatory Mite (Phytoseiulus persimilis) in Sustainable Strawberry Fields (친환경 딸기 재배 농가에서 칠레이리응애를 이용한 점박이응애 생물적 방제)

  • Kim, Do-Ik;Kim, Seon-Gon;Shin, GiI-Ho;Seo, Jong-Bun;Choi, Kyong-Ju;Lim, Kyeong-Ho;Kim, Sang-Soo
    • Korean Journal of Organic Agriculture
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    • v.14 no.3
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    • pp.315-323
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    • 2006
  • The potential of the predatory mite Phytoseiulus persimilis (Acarina : Phytoseiidae) to control two spotted spider mite Tetranychus urticae (Acarina : Tetranychidae) was investigated on sustainable strawberry fields in Jeonnam area. The density of T. urticae increased from 4th and 7th weeks after single and two timings release P. persimilis, respectively. On the three timings of release plot, number(density) of T. urticae on a leaf maintained fewer than 10 during the 15 weeks after release. In the 1,000 release of P. persimilis per $100m^2$ plot, P. persimilis could not suppress T. urticae. In the 2,000 release plot, P. persimilis could suppress T. urticae with low density which was the similar in the 3,000 release plot. Two-spotted spider mite, T. urticae, occurred from late March and increased density in Hampyeong area. In the P. persimilis released field, T. urticae inhibited continuously after release. In Boseong area, density of P. persimilis increased 50 per 10 leaves through increasing of T. urticae. Percent of occurrence of T. urticae showed high $10.5{\sim}75.5%$ in none-release predatory mite but not high in release treatment. T. urticae on sustainable strawberry field could be inhibited by P. persimilis.

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Effects of Activin on Testosterone-primed Immature Rainbow Trout Gonadotropin Release in vitro (Testosterone 처리한 미성숙 무지개송어 뇌하수체의 세포배양계에서 생식소자극초르몬 분비에 대한 Activin의 효과)

  • KIM Dae-Jung;HAN Chang-Hee;AIDA Katsumi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.2
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    • pp.204-210
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    • 1999
  • The present studies were conducted to evaluate the effects of activin-A on gonadotropins (GTHs) release in testosterone-treated immature rainbow trout Oncorhpynchus mykiss. The administration of testosterone elevated pituitary level of GTH II but not of GTH I. In this study using primary cultures of dispersed pituitary cells in static incubation, dose-dependent increases in GTH II release was observed in the activin-treated group at day 3 of incubation (long-term incubation), but not at day 1 of incubation (short-term incubation). Dopamine, a potent inhibitor of gonadotropin-releasing hormone (GnRH)-stimulated GTH II release in rainbow trout, was only partially effective in decreasing actvin-induced GTH II release. Furthermore, salmon GnRH (sGnRH)-stimulated GTH II release was not potentiated by the pretreatment with activin. However, the control mechanisms of GTH I release by activin and other hormones were not observed in the all tested experiments. The results of these studies support the contention that in contrast with the usual stimulatory effects of activin on GTH release in mammals, activin exerts long-term stimulatory actions on GTH II release in rainbow trout. The control mechanism of GTH I release, however, is a question that remains to be elucidated.

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Clinical Study on Fluvoxamine Combined with Oxycodone Prolonged-Release Tablets in Treating Patients with Moderate to Severe Cancer Pain

  • Xiao, Yang;Liu, Jun;Huang, Xin-En;Ca, Li-Hua;Ma, Yi-Min;Wei, Wei;Zhang, Rong-Xia;Huang, Xiao-Hong;Chang, Juan;Wu, Yi-Jia
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.23
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    • pp.10445-10449
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    • 2015
  • Objective: To observe treatment effects and safety of fluvoxamine combined with oxycodone prolonged-release tablets in treating patients with moderate to severe cancer pain. Methods: Patients confirmed pathologically with cancer and complicated with moderate to severe pain, were divided into control and experimental groups. Oxycodone prolonged-release tablets, with or without fluvoxamine, were administrated to all study patients until pain relief. Degree of pain relief, dose of oxycodone prolonged-release tablets, side effects and quality of life were compared before and after treatment. Results: In total, 120 patients were recruited. No statistically significant difference was detected regarding age, gender, types of cancer, KPS between two groups of patients (P>0.05). Baseline pain score of patients with moderate pain in treatment and control group was $4.9{\pm}0.8$ and $5.1{\pm}0.8$, respectively; and decreased to $1.8{\pm}1.1$ and $1.2{\pm}1.1$ after treatment, respectively. Pain intensity was significantly reduced in the treatment group (P=0.028). Average daily consumption of oxycodone prolonged-release tablets was ($54.0{\pm}19.6$) mg and ($44.7{\pm}18.7$) mg respectively, which is lower in treatment grpup than in control group, but the difference was not statistically significant (P=0.065). Baseline pain score of patients with severe pain in treatment and control groups were $8.3{\pm}1.1$ and $8.3{\pm}1.1$, respectively; and pain intensity after treatment decreased to $2.9{\pm}1.0$ and $2.3{\pm}1.0$. Pain intensity was significantly reduced in the treatment group, with statistical significance (P=0.026). Average daily consumption of oxycodone prolonged-release tablets was ($132.0{\pm}42.2$) mg and ($110.7{\pm}33.9$) mg, respectively, which is lower in treatment group than in control group, and the difference was statistically significant (P=0.035). In terms of quality of life, patients in treatment group had better performance status, daily activity, mood, and sleep than that in control group (P < 0.05). Patients in two groups had similar side effects, eg., constipation, nausea/vomiting, lethargy, dizziness, itchy skin, dysuria, and ataxia. Lower incidence of nausea/vomiting, lethargy, was obtained from patients in treatment than in control group, while significant low constipation was observed in treatment than in control group (35.0% vs 49.2%, P=0.026). Conclusion: Fluvoxamine combined with oxycodone prolonged-release tablets could be more effective in treating patients with cancer pain, and could reduce the dosage of oxycodone prolonged-release tablets and thus be associated with lower side effects, and improved quality of life.

Dried Bacillus subtilis Culture Reduced Ammonia Gas Release in Poultry House

  • Santoso, U.;Ohtani, S.;Tanaka, K.;Sakaida, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.5
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    • pp.806-809
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    • 1999
  • The present study showed the advantages of dried Bacillus subtilis culture (DBSC) supplementation on reducing ammonia gas release in the poultry house. In Experiment 1, 65-week-old Hyline W-36 hens were raised in individual wire-floor cages in a windowless house, and divided into two groups of 180 hens each. One group was fed diets without DBSC as the control and another group was fed a diet supplemented with 2% DBSC. In Experiment 2, 2-week-old broiler chicks were divided into 3 treatment groups of 20 chicks each and maintained in individual floor cages. One group was fed the diet without DBSC and other two groups were fed the diet supplemented with 1 or 2% DBSC, respectively. In experiment 1, DBSC consistently reduced ammonia gas release in the laying house (p<0.01) and manure storage facilities (p<0.01). incubation of feces for 1, 2, 3, 4, 5, 6, 24 or 48 hours showed that DBSC consistently reduced ammonia gas release. In Experiment 2, DBSC reduced ammonia gas release in the broiler house; however, DBSC had no effect on total N, urate-N and ammonia-N contents of feces, but it improved cumulative N utilization and decreased serum urea-N concentration when chicks when chicks were fed 1% DBSC.

Impact of Thickness of Sand Capping on Phosphorus Release Rate from Sediment (모래 캡핑 두께가 퇴적물 인 용출에 미치는 영향)

  • Jeong, Woo-Hyeok;Kim, Geon-Ha
    • Korean Journal of Ecology and Environment
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    • v.39 no.3 s.117
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    • pp.331-339
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    • 2006
  • This research was carried out to understand the impacts of thickness of sand capping to control phosphorus release from sediment into overlying water. As capping effectively retards release flux, phosphorus concentration in water body can be maintained if phosphorus release rate was kept under microbial degradation rate. With capping thickness increases, deaeration rate become less, while reaeration coefficient become higher. Phosphorus release rate and capping thickness were linearly correlated. The results of regression analysis indicated that phosphorus release can be controlled effectively by sand capping of least 20${\sim}$40 mm thickness.

Cortex Mori Inhibits the CGG-specific IgE-Dependent Histamine Release

  • Chai, Ok-Hee;Kyoung, Jin-Kang;Park, Myoung-Hee-;Lee, Moo-Sam-;Jun, Byoung-Deuk
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.244-244
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    • 1994
  • Cortex Mori, the root bark of mulbery tree has been used as an antiphlogistic, diuretic, and expectorant in herbal medicine. The purpose of this study is to evaluate chicken gamma globulin (CGG)-specific IgE-induced morphologic and functional changes in rat peritoneal mast cells (RPMC), and to determine whether Cortex Mori could inhibit the CGG-specific IgE-depeildent mast cell degranulation and histamine release from RPMC. Results are 1) the degranuration and histamine release from RPMC were not induced within 1 hour after addition of Cortex Mori alone, 2) the CGG and CGG-specific IgE-Induced degranulation from RPMC was observed within 10 minutes, 3) the histamine release from RPMC sensitised with CGG-specific IgE was induced by tile addition of CGG, 4) CGG-specific IgE-dependent degranulation rate in RPMC pretreated with Cortex Mori was significantly Inhibited, compared to that of control group without Cortex Mori pretreatment, and 5) the CGG-specific IgE-dependent histamine release from RPMC was significantly inhibited by pretreatment with Cortex Mori. These data suggest that Cortex Mori contains some substances with capabilities to inhibit CGG-specific IgE-dependent degranulation and histamine release from RPMC.

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Preparation and Dissolution Profiles of Controled Release Formulations Containing Tamsulosin Hydrochloride (염산 탐스로신을 함유하는 방출제어형 제제의 제조 및 용출거동)

  • Yun, Jae-Nam;Kim, Jeong-Soo;Kim, Dong-Woo;Lee, Gye-Won;Jee, Ung-Kil
    • Journal of Pharmaceutical Investigation
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    • v.35 no.6
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    • pp.445-451
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    • 2005
  • As a selective ${\alpha}_{1A}-adrenoreceptor$ antagonist, tamsulosin has been used clinically for urinary obstructed patients with benign prostatic hyperplasia. The single and multi-layered pellets containing tamsulosin hydrochloride were prepared in an effort to control the drug release, avoiding dose-dependent side effects of tamsulosin hydrochloride upon oral administration. The drug release from multi-layered pellets was substantially controlled, compared with single layered pellets. The drug release from coated pellets with single or multi layer was affected by the nature of coating agent, the percentage of coating level and the presence of hydrophilic material in coating layer. In conclusion, the controlled release oral delivery system using multi-layered pellet is very useful for tamsulosin hydrochloride, resulting in improvement of patient compliance and therapeutic drug levels for a longer period of time.

Prediction of Phosphorus Transport from Sediment and Development of Phophorus Control Technology - I. Prediction of Phosphorus Transport from Sediment (저질토로부터의 인의 용출거동 예측 및 제어기술 개발 - I. 저질토로부터의 인의 용출거동 예측)

  • Lee, Jung-Yub;Kang, Seon-Hong
    • Journal of Korean Society of Water and Wastewater
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    • v.13 no.2
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    • pp.89-94
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    • 1999
  • In this study small glass columns with 2.5cm inner diameter and 24.5cm length were used as many as the sample numbers to study the effects of initial pH, temperature, dissolved oxygen concentration, and sediment depth on the release of phosphorus from lake sediment. No phosphorus release occurred at $10^{\circ}C$ with all pHs, and release rate at $25^{\circ}C$ was higher than that at $35^{\circ}C$ with pH 4 and reverse trends were observed at pH 7 and 10. Under all conditions, DO concentrations were decreased and equilibrium was obtained after 4-8 days when phosphorus release started and the Do concentrations were less than 1 mg/l. Sediment depth had little effect on phosphorus release rate. It was found that relation between released SRP(Soluble Reactive Phosphorus) concentration and time was zero order reaction and reaction rate coefficients were obtained. The amount of phosphorus release from lake sediment can be predicted by considering these k values.

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Preparation and Controlled Release of Microcapsules Containing $Ketoprofen-{\beta}-Cyclodextrin$ Solid Dispersion (케토프로펜-${\beta}$-시클로덱스트린 고체분산체의 마이크로캅셀화 및 제어 방출)

  • Chun, In-Koo;Park, Jung-Hwa
    • Journal of Pharmaceutical Investigation
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    • v.22 no.1
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    • pp.33-40
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    • 1992
  • This study was aimed to control the release characteristics of ketoprofen by microencapsulating $ketoprofen-{\beta}-cyclodextrin\;(KF-{\beta}-CyD)$ solid dispersion with Eudragit RS by the phase separation method using a nonaqueous vehicle. KF alone was also microencapsulated with Eudragit RS by the evaporation process in water phase. The results obtained showed that it was not possible to microencapsulate KF alone by phase separation in a chloroform-cyclohexane system while it was easy to microencapsulate $(KF-{\beta}-CyD)$ solid dispersion system. For the microcapsules, the release test was performed in the first fluid (pH 1.2) and the second fluid (pH 6.8) of K.P.V disintegration medium at $37^{\circ}C$. The release of KF from $(KF-{\beta}-CyD)$ solid dispersion microcapsules (1:1 core wall ratio) was more sustained than that from KF microcapsules, and followed zero-order kinetics. Especially, solid dispersion microcapsules showed pH-independent release patterns with higher wall to core ratio (1:1 w/w).

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