• Journal of Pharmaceutical Investigation
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• v.21 no.1
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• pp.1-10
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• 1991

Hydrogels containing ketoprofen were prepared by adding NaOH or $Ca(OH)_2$ solution to Eudragit L, S and Eudispert hv at various concentration. And xerogels were prepared by drying hydrogels. On the other hand, organogels containing ketoprofen were prepared by mixing Eudragit L or S and propylene glycol. Effects of polymer content and base on drug release were investigated using KP V dissolution method. The release rate of ketoprofen from Eudragit L & S hydrogel decreased with increasing in polymer content. And the drug release rate from cal. hydroxide based gels were more decreased than that from sod. hydroxide based gels. At pH 7.2 dissolution medium, e release of ketoprofen from Edispert hv hydrogel followed apparent zero order kinetics. The release of ketoprofen from xerogel involved in simultaneous absorption of water and desorption of ketoprofen via a pH-dependant swelling controlled mechanism. The release of ketoprofen from Eudragit S organogels followed apparent zero order kinetics, providing strong evidence for a surface erosion mechanism.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.317-319
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• 2000

We fabricated the QCM with Langmuir-Blodgett(LB) film deposited at the different subphase pH and investigated the resonant frequency response by the injection of organic gas response. In the $\pi$-A isotherms, the monolayer on the air/water interface had different limiting area per molecule and showed more condensed status as increasing the subphase pH. When palmitic acid LB film was deposited on the QCM, the resonant frequency shift was proportional to the deposited layer and had more resonant frequency shift in the case of the higher pH range as expected. In the resonant frequency for the injection of organic gas, it has been improved in the case of LB film fabricated at the lower subphase pH range and dependant upon the molecular weight of organic gas.

• Environmental Analysis Health and Toxicology
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• v.16 no.4
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• pp.161-170
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• 2001

In aqueous ecosystems, the level of toxicity is highly responsive dependant to multiple variables, including rainfall, sunlight, pH, adhesion, etc. Because Korea has particularly distinct wet and dry seasons, the toxicity of pollutants in rivers or streams is dependant on the sampling season and time. In order to examine the effects of rainfall on toxicity, sediment samples were collected from five sites along the Keumho river. It was found that Microtox toxicity levels were generally higher during the dry season than the wet season. It indicated that river pollutants are carried off more quickly by the water during the wet season. As a result, it was recommended that the point sources of pollutants of the Keumho river would be placed between KH3 (Paldalgyo) and KH4(Keumhogyo), KH4(Keumhogyo) and KH5(Dasa).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.2
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• pp.372-379
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• 2007

The converter slag can be used to remove phosphate ion into the form of solid state from the wastewater. This research aims to evaluate the change of pH, alkalinity, leaching of positive ion in the wastewater and the removal of phosphate from the initial condition of wastewater. The change of pH was abruptly increased upto pH 11 for the initial condition of pH from 7.0 to 8.5 fer 0.5 unit of pH. The alkalinity was steadily increased from 10 hours of reaction time not same as pH increase. The removal of phosphate was very effective till 10 hours of reaction then it was slow after that time. The positive ion, magnesium ion was leached from the concentration of 2.0 mg/L to 4.3mg/L at the reaction time of 27 hours and 36 hours. Therefore, converter slag can be used to remove the phosphate in the form of Struvite from the wastewater.

• Macromolecular Research
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• v.15 no.4
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• pp.385-391
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• 2007

Block copolymer micelles are generally formed via the self-assembly of amphiphilic block copolymers in an aqueous medium. The hydrophilic and hydrophobic blocks form shell and core micelles, respectively. The block copolymers of methoxy poly(ethylene glycol) (MPEG)-b-poly(2-diisopropylamino)ethyl methacrylate (PDPA) were synthesized via atom transfer radical polymerization, with the macro initiator synthesized by the coupling of 2-bromoisobutyryl bromide with MPEG in the presence of a triethyl amine base catalyst. The atom transfer radical polymerization of 2-diisopropylamino)ethyl methacrylate was performed in conjunction with an N,N,N',N",N"-pentamethyl-diethylenetriamine/copper bromide catalyst system, in DMF, at $70^{\circ}C$. The pH induced micellization/demicellization was studied using fluorescence, with a pyrene probe. Furthermore, the pH dependent micellization was confirmed using the microviscosity method, with a dipyme fluorescence probe. The pH dependant micelle size distribution was studied using dynamic light scattering. The characterization of the synthesized polymers was established using gel permeation chromatography and from the $^1H-nuclear$ magnetic resonance spectroscopy.

• Journal of Acupuncture Research
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• v.17 no.2
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• pp.169-186
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• 2000

To study anti-cancer effect and molecular biological mechanism of bee venom for aqua-acupuncture, the effects of bee venom on cell viability, apoptosis, and cell cycle were analyzed using MTT assay, tryphan blue assay, [3H]thymidine release assay, flow cytometric analysis, activity of caspase-3 protease activity assay, and immunocytometric analysis of PCNA. To explore whether anti-cancer effects of bee venom are associated with the transcriptional control of gene expression, quantitative RT-PCR analysis of apoptosis- and cell cycle-related genes was performed. The obtained results are summarized as follows: 1. The MTT assay demonstrated that cell viability was decreased by bee venom in a dose-dependant manner. 2. Significant induction of apoptosis was identified using tryphan blue assay, [$^3H$]thymidine release assay, and flow cytometric analysis of sub $G_1$ fraction. 3. In analysis of caspase-3 protease activity, the activity had increased significantly, in a dose-dependant manner. 4. Quantitative RT-PCR analysis of the apoptosis-related genes showed that Bcl-2 and $Bcl-X_L$ were down-regulated whereas Bax was up-regulated by bee venom treatment. 5. In flow cytometric analysis of cell cycle and immunocytometric analysis of PCNA expression, cell numbers of $G_1$ phase was increased by a dose-dependant manner. 6. In quantitative RT-PCR analysis of the cell cycle-related genes, p21, p27, and p57 were increased, while Cyclin D1, CDK4, c-Myc, c-Fos, and Histone H3 were decreased. In contrast, there were no remarkable changes in expression levels of CDC2 and c-Jun.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.295-298
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• 2004

It was revealed that leaching of elements were partly inhibited because seawater contains plenty of dissolved ions than fresh water. On the other hands, the low activity coefficient and the formation of complex with chloride and sulfate play roles in enhancing element leachability. However, the pH buffaring capacity of seawater is the most important factor that makes the leaching of elements and its chemical behavior in the seawater system different from those in the fresh water environments. In general, the leaching from the weathered ash was smaller than that from the fresh ash. However, it was revealed that the leaching of Si, Fe, Al, Mn, phosphate, and some other elements were independent of ash weathering. They were dependant only on the pH of the solutions.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.455-458
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• 2003

We investigated the leaching of elements from anthracite ashes by interactions with seawater. The results show that consumption rates of dissolved oxygen are 7.5 times greater in the seawater system than in the fresh water system and indicate that the differences in DO consumption rate may plat a role in regulating the element leaching from the coal ashes. It is revealed that seawater's pH buffering capacity is the most important factor that makes the leaching of elements and their chemical behaviors in the seawater system different from those in the fresh water environments. In overall, element leaching from the weathered ash is smaller than that from the fresh ash. However, the leaching of Si, Fe, Al, Mn, phosphate, and some other elements were independent of weathering. They were dependant only on the pH of the solutions.

• Microbiology and Biotechnology Letters
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• v.7 no.3
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• pp.141-147
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• 1979

Naringinase from Atpergillus nidulans was immobillized on DEAE-Sephadex A-25 and its characteristics were studied. The optimal conditions for the preparation of the immobilized enzyme were as follow; optimal pH, incubation time and the suitable amount of enzyme were 6.0, 30 min. and 110 units per gram of the dried ion exchage resin, respectively. The optimal pH of the immobilized enzyme was higher than that of the native enzyme. The optimal temperature increased from 4$0^{\circ}C$ to 5$0^{\circ}C$. The heat and pH stability of the immobillized enzyme were better than those of the native enzyme. No significant difference in the Michaelis constant was detected. Activation energy of the immobilized enzyme was 7.96 Kcal/mole, and the apparent Michaelis rate equation was used to describe the action of this material. The degree of hydrolysis was dependant on the flow rate at low rate of perfusion through the column. As the flow rate increased, the value of the apparent Km decreased.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.6
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• pp.1441-1447
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• 2003

The purpose of this research was to investigate the effects of Chungjokupye-tang(CJKPT) on the anti-carcinogenic action. The cell viability of mouse spienocytes and thymocytes were enhanced by the addition of CJKPT. CJKPT were increased of splenic and thymic T lymphocytes, such as T/sub H/ cells were markedly increased by the treatment of CJKPT in vivo. CJKPT treatment induced the apoptotic cell death of Jurkat and HL60 leukemia cells. CJKPT reduced mitochondrial transmembrane potential and increased the expression of ICE, c-myc and p53 gene in Molt-4cells dose dependant manner. These results suggest that CJKPT have an anti-carcinogenic action via immunoregulatory mechanism.