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Preparation and Release Properties of Oromucosal Moisture-activated Patches Containing Lidocaine or Ofloxacin (오플록사신 및 리도카인 함유 수분 감응성 구강점막 패취제의 제조 및 방출 특성)

  • Gwak, Hye-Sun;Song, Yeon-Hwa;Chun, In-Koo
    • Journal of Pharmaceutical Investigation
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    • v.35 no.6
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    • pp.417-422
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    • 2005
  • This study was aimed to design and formulate the moisture-activated patches containing ofloxacin and lidocaine for antibacterial and local anesthetic action. The solubility of lidocaine at $32^{\circ}C$ in various vehicles decreased in the rank order of PG $759.5{\pm}44.5\;mg/mL$ > PGL > IPM > PEG 300 > PEG 400 > Ethanol > PGMC > DGME > PGML > OA > $Captex^{\circledR}\;300$ > $Captex^{\circledR}\;200$ > water $(4.0{\pm}0.1\;mg/mL)$. Ofloxacin revealed very low solubility, which the highest solubility was obtained from PEG 400 $(18.7{\pm}6.3\;mg/mL)$ among the vehicles used. The addition of lactic acid increased the solubility of ofloxacin dramatically; the solubility at 5% lactic acid was $133.7{\pm}9.7\;mg/mL$. As $2-hydroxypropyl-{\beta}-cyclodextrin$ was added at the concentrations of 40, 80, 120, 160 and 200 mM, the solubilities of lidocaine and ofloxacin were enhanced up to three and two times, respectively, with concentration-dependent pattern. Gel intermediates for filmtype patches were prepared with mucoadhesive polymer, viscosity builders, lidocaine or ofloxacin at pH values from 5 to 7. Gels were cast onto a release liner and dried at room temperature. Dried patch was attached onto an adhesive backing layer, thus forming a patch system. Patches containing a single drug component were characterized by in vitro measurement of drug release rates through a cellulose barrier membrane. The release study was carried out at $37^{\circ}C$ using a Franz-type cell. Receptor solutions were isotonic phosphate buffers (pH 7.4). Samples $(100\;{\mu}L)$ were taken over 24 hours and quantitated by a verified HPLC method. The releases from all tested were proportional to the square root of time. The release rates were 0.9, 157.3 and $281.7\;{\mu}g/cm^{2}/min^{1/2}$ for the lidocaine patches and 19.8,37.2 and $50.7\;{\mu}g/cm^{2}/min^{1/2}$ for the ofloxacin patches at the concentrations of 0.3, 0.5 and 1 %, respectively. The release rates were dose dependent in both drug patches $(R^{2}\;=\;0.9077\;for\;lidocaine;\;R^{2}\;=\;0.9949\;for\;ofloxacin)$ and those were also thickness-dependent $(R^{2}\;=\;0.9246\;for\;lidocaine;\;R^{2}\;=\;0.9512\;for\;ofloxacin)$.

ATP-Inhibited Ribonuclease of Bacillus subtilis (Bacillus subtilis ATP 조해(阻害) Ribonuclease에 관한 연구)

  • Lee, Taik-Soo
    • Applied Biological Chemistry
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    • v.18 no.3
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    • pp.167-176
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    • 1975
  • As a study on the ATP-inhibited ribonuclease of Bacillus subtilis the screening work for obtaining the ATP-inhibited ribonuclease negative mutant were carried out. And mutant strain was selected by the treatment of N-methyl-N'-nitro-N-nitrosoguanidine (NTG). For the selected strain the enzyme purification and some physiological properties were examined and the results obtained were as follows. 1. Among tested 1817 strains with the treatment of NTG, 101 strain was selected as a mutant strain. 2. ATP-inhibited ribonuclease was tentatively purified by several independent column chromatography. The results with Sephadex G-75 column were 30 times purification, 99% recovery, and 20 times purification, 98% recovery, respectively. 3. ATP-inhibited ribonuclease was purified by 60 times through acid treatment, ammonium fractionation, and two successive chromatography. 4. The purified ribonuclease were shown to be effectively concentrated in robonnclease content and to have reduced numbers of protein band on Disc electrophoresis. 5. This enzyme degraded single-stranded RNA to 2',3'-cyclic AMP, 2',3'-cyclic CMP, 2',3,-cyclic GMP, 2',3'-cyclic UMP and some unknown intermediates. The enzyme could not split double-stranded RNA.

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A Review : On Exercise Performance Induction Gene Factors Change (운동이 유전자 조절물질에 미치는 영향에 관한 고찰)

  • Um, Ki-Mai;Yang, Yoon-Kwon;Kim, Tae-Woo
    • Journal of Korean Physical Therapy Science
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    • v.8 no.1
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    • pp.745-758
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    • 2001
  • The purpose of study to phenomenological examine and the mechanism regarding the gene(DNA, RNA, Protein) and sports to studied, analyzed. and evaluated. This review considers the evidence for genetic effects in several determinants of endurance performance and resistance performance, namely: body measurements and physique, body fat pulmonary functions, cardiac and circulatory functions, muscle characteristics. substrate utilization, maximal aerobic power and other. Moreover, the response to aerobic training of indicators aerobic work metabolism and endurance performance is reviewed, with emphasis on the specificity of the response and the individual differences observed in training ability. This study indicate that improvement of 'Enhancer Action' in RNA genes changed by exercise or sports. Moreover exercise was effect on Central Dogma with DNA makes RNA makes Protein. and think that occurred with exercise influence on skeletal muscle into cell have to Myosin Heavy Chain (MHC) changed was after exercise performance, which accompanied into skeletal muscle that were exercise-induces gene-modulation that is, take gene mutations. This study known that existed hormone(epinephrine)-immune system with interaction. Exercise were altered insulin binding and MAP Kinase signaling increased into immune cells. This review suggested that the high rate of glutamine utilization by cells of the immune system serves to maintain a high intra cellular concentration of the intermediates of biosynthetic pathways such that optimal rates of DNA, RNA and protein synthesis can be maintained. In the absence of glutamine, lymphocytes do not proliferate in vitro: proliferation increase greatly as the glutamine concentration increase. Glutamine is synthesized in skeletal muscle. Skeletal muscle and plasma glutamine levels are lowered by sepsis, injury, bums, surgery and endurance exercise and in the overtrained athlete. The study of result show that production of ET-1 is markedly increased tissue specifically in the heart by exercise without appreciable changes in endothelin-converting enzyme and endothelial receptor expressions, suggest that myocardial ET-1 may participate in modulation of cardiac function during exercise. Conclusionally, this study indicate that improvement of 'Enhancer Action' in RNA genes changed by exercise or sports. Moreover exercise was effect on Central Dogma with DNA makes RNA makes Protein. This study is expected to contribute the area of sports science, medicine, hereafter more effort is required to establish the relation between gene alters and exercise amount.

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Study on Conversion of Carbon Dioxide to Methyl Alcohol over Ceramic Monolith Supported CuO and ZnO Catalysts (세라믹 모노리스에 담지된 CuO와 ZnO계 촉매에 의한 이산화탄소의 메탄올로의 전환에 관한 연구)

  • Park, Chul-Min;Ahn, Won-Ju;Jo, Woong-Kyu;Song, Jin-Hun;Kim, Ki-Joong;Jeong, Woon-Jo;Sohn, Bo-Kyun;Ahn, Byeong Kwon;Chung, Min-Chul;Park, Kwon-Pil;Ahn, Ho-Geun
    • Journal of Korean Society for Atmospheric Environment
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    • v.29 no.1
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    • pp.97-104
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    • 2013
  • Methyl alcohol is one of the basic intermediates in the chemical industry and is also being used as a fuel additive and as a clean burning fuel. In this study, conversion of carbon dioxide to methyl alcohol was investigated using catalytic chemical methods. Ceramic monoliths (M) with $400cell/in^2$ were used as catalyst supports. Monolith-supported CuO-ZnO catalysts were prepared by wash-coat method. The prepared catalysts were characterized by using ICP analysis, TEM images and XRD patterns. The catalytic activity for carbon dioxide hydrogenation to methyl alcohol was investigated using a flow-type reactor under various reaction temperature, pressure and contact time. In the preparation of monolith-supported CuO-ZnO catalysts by wash-coat method, proper concentration of precursors solution was 25.7% (w/v). The mixed crystal of CuO and ZnO was well supported on monolith. And it was known that more CuO component may be supported than ZnO component. Conversion of carbon dioxide was increased with increasing reaction temperature, but methyl alcohol selectivity was decreased. Optimum reaction temperature was about $250^{\circ}C$ under 20 atm because of the reverse water gas shift reaction. Maximum yield of methyl alcohol over CuO-ZnO/M catalyst was 5.1 mol% at $250^{\circ}C$ and 20 atm.

Effect of Ethanol on the Reduction of Propionate under Anaerobic Condition (혐기성 조건에서 에탄올의 주입에 따른 프로피온산의 저감에 관한 연구)

  • Hyun, Seung-Hoon;Kim, Do-Hee;Park, Soo-Jin;Hwang, Moon-Hyun;Kim, In S.
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.10
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    • pp.1869-1879
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    • 2000
  • A series of experiments were conducted for modeling the fate and effect of the coupled oxidation reduction reaction of ethanol and propionate recognized as important intermediates in anaerobic degradation metabolism. Anaerobic kinetics for conversion of propionate and the interaction with ethanol were investigated using the model of specific substrate priority utilization effect. Seed cultures for the experiment were obtained from an anaerobically enriched steady-state propionate master culture reactor (HPr-MCR), ethanol-propionate master culture reactor (EtPr-MCR) and glucose master culture reactor (Glu-MCR). Experiments were consisted of four phases. Phase I, II and III were conducted by fixing the propionate organic loading as 1.0 g COD/L with increasing ethanol loading of 0, 100, 200, 400 and 1,000 mg/L, to find metabolic interaction of ethanol and propionate degradation by each enriched anaerobic culture. In phase IV, different mixing ratios of Glu-MCR and HPr-MCR cultures with fixed propionate organic loading, 1.0 g COD/L, were applied to observe the propionate degradation metabolic behavior. In the results of this study, different pathways of propionate and ethanol conversion were found using a modified competitive inhibition kinetic model. Increase of $K_{s2}$ value reflected the formation of acetate followed by ethanol degradation. In addition. $K_3$ value was increased slightly as the reactions of acetate formation and degradation were occurred in acetoclastic methanogenesis.

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Effects of Operating Parameters on Phenol Degradation by Pulsed Corona Discharges in Aqueous Solutions (펄스 코로나 방전에 의한 페놀 분해에 미치는 운전변수의 영향)

  • Chung, Jae-Woo;Moon, Ji-Hoon;Park, Eun-Ok
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.1
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    • pp.79-86
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    • 2010
  • Effects of operating parameters such as applied voltage, solution conductivity, ferrous ion concentration, electrode material on phenol degradation by pulsed corona discharges were investigated in laboratory scale experiments. The increase of applied voltage enhanced the phenol degradation by generating more energetic electrons. The solution conductivity inversely affected phenol removal rate in the tested ranges because the increase of conductivity decreased the electric field strength through the liquid phase. The addition of ferrous sulfate promoted the phenol degradation through the OH radical production by the Fentonlike reactions between ferrous ion and hydrogen peroxide generated by pulsed corona discharges. Catechol and hydroquinone were detected as primary intermediates of phenol degradation and the decrease of pH and the increase of conductivity were observed probably due to the generation of organic acids. Almost all of the initial phenol was disappeared and 29% of total organic corbon (TOC) was removed in the condition of 0.5 mM of ferrous sulfate after approximately 230 kJ of discharge energy transferred to the reactor.

Preparation and Flame Retardancy Effect of Polyurethane Coatings Containing Phosphorus and Chlorine (인과 염소를 함유하는 폴리우레탄 도료의 제조와 난연효과)

  • Shim Il-Woo;Jo Hye-Jin;Park Hong-Soo;Kim Seong-Kil;Kim Young-Geun
    • Polymer(Korea)
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    • v.30 no.3
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    • pp.238-246
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    • 2006
  • The aim of this study is to enhance the flame retardancy by the synergism effect of chlorine and phosphorus groups. The flame-retardant polyurethane coatings containing chlorine and phosphorus compounds were synthesized. After synthesizing the intermediate products of tetramethylene bis (orthophosphate) (TMBO) and neohexanediol trichlorobenzoate (TBA-adduct), the condensation polymerization was performed with four different monomers of two intermediates, 1,4-butanediol, and adipic acid to obtain four-component copolymer(TTBA). The two-component flame-retardant polyurethane coatings (TTBA-10C/HDI-trimer=TTHD-10C, TTBA-20C/HDI-trimer=TTHD-20C, TTBA-30C/HDI trimer=TTHD-30C) were obtained by curing reaction at room temperature with the synthesized TTBAs and hexamethylene diisocyanate (HDI)-trimer as a curing agent. The obtained TTHDs were made into coating samples and used as test samples for various physical properties. The physical properties of the flame-retardant coatings containing chlorine and phosphorus groups were generally inferior to those containing only phosphorus group. Flame retardancy was tested by vortical and horizontal combustion method, and $45^{\circ}$ Meckel burner method. Since the retardancy of flame-retardant coatings containing chlorine and phosphorus groups was better than that containing only phosphorus group, it could be concluded that the retardancy by the synergism effect of chlorine and phosphorus groups exhibited.

Determination of the Langmuir and Temkin Adsorption Isotherms of H for the Cathodic H2 Evolution Reaction at a Pt/KOH Solution Interface Using the Phase-Shift Method

  • Chun Jang-H.;Jeon Sang-K.;Chun Jin-Y.
    • Journal of the Korean Electrochemical Society
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    • v.9 no.1
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    • pp.19-28
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    • 2006
  • The phase-shift method for determining the Langmuir, Frumkin, and Temkin adsorption isotherms ($\theta_H\;vs.\;E$) of H for the cathodic $H_2$ evolution reaction (HER) at a Pt/0.1 M KOH solution interface has been proposed and verified using cyclic voltammetric, differential pulse voltammetric, and electrochemical impedance techniques. At the Pt/0.1 M KOH solution interface, the Langmuir and Temkin adsorption isotherms ($\theta_H\;vs.\;E$), the equilibrium constants ($K_H=2.9X10^{-4}mol^{-1}$ for the Langmuir and $K_H=2.9X10^{-3}\exp(-4.6\theta_H)mol^{-1}$ for the Temkin adsorption isotherm), the interaction parameters (g=0 far the Langmuir and g=4.6 for the Temkin adsorption isotherm), the rate of change of the standard free energy of $\theta_H\;with\;\theta_H$ (r=11.4 kJ $mol^{-1}$ for g=4.6), and the standard free energies (${\Delta}G_{ads}^{\circ}=20.2kJ\;mol^{-1}$ for $k_H=2.9\times10^{-4}mol^{-1}$, i.e., the Langmuir adsorption isotherm, and $16.7<{\Delta}G_\theta^{\circ}<23.6kJ\;mol^{-1}$ for $K_H=2.9\times10^{-3}\exp(-4.6\theta_H)mol^{-1}$ and $0.2<\theta_H<0.8$, i.e., the Temkin adsorption isotherm) of H for the cathodic HER are determined using the phase-shift method. At intermediate values of $\theta_H$, i.e., $0.2<\theta_H<0.8$, the Temkin adsorption isotherm ($\theta_H\;vs.\;E$) corresponding to the Langmuir adsorption isotherm ($\theta_H\;vs.\;E$), and vice versa, is readily determined using the constant conversion factors. The phase-shift method and constant conversion factors are useful and effective for determining the Langmuir, Frumkin, and Temkin adsorption isotherms of intermediates for sequential reactions and related electrode kinetic and thermodynamic data at electrode catalyst interfaces.

Uranium Recovery from Nuclear Fuel Powder Conversion Plant Filtrate and its Thermal Decomposition Characteristics (핵연료분말 제조공정에서 발생된 여액으로부터 우라늄 회수 및 회수된 우라늄 화합물의 열분해 특성)

  • Jeong, Kyung-Chai;Jeong, Ji-Young;Kim, Byung-Ho;Kim, Tae-Joon;Choi, Jong-Hyeun
    • Journal of the Korean Ceramic Society
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    • v.39 no.2
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    • pp.204-209
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    • 2002
  • In this study, $UO_4{\cdot}2NH_4F$, the precipitates which has low solubility, was obtained by chemical precipitation method to recover and reuse the trace uranium from the liquid waste producing in AUC process and for this compound it was characterized by means of chemical analysis, TG-DTA, XRD and FT-IR analyses. This compound was analyzed as $UO_4{\cdot}2NH_4F$ and shape of this precipitate was hexagonal type, having the size of 2∼3 ${\mu}m$. Also, the intermediates were obtained as $UO_4F,\;UO_4,\;UO_3,\;and\;U_3O_8$ by the thermal decomposition over the temperature of 220, 310, 515 and 640$^{\circ}C$, respectively. It is concluded that under the condition of a constant heating rate of 5$^{\circ}C$/min in air atmosphere range of between room temperature and 800$^{\circ}C$, thermal decomposition reaction mechanism of $UO_4{\cdot}2NH_4F$ is as follow; $UO_4{\cdot}2NH_4F{\rightarrow}UO_4F{\rightarrow}UO_4{\rightarrow}UO_3{\rightarrow}U_3O_8$.

Porous silica ceramics prepared by sol-gel process-Effect of $H_2O/TEOS$ molar ratio- (솔-젤법에 의한 다공성 실리카 세라믹스의 제조-$H_2O/TEOS$ 몰비의 영향-)

  • Lee, Jin-Hui;Kim, Wha-Jung;Lee, Joon
    • Journal of the Korean Ceramic Society
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    • v.34 no.2
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    • pp.216-224
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    • 1997
  • Porous silica ceramics were prepared(with HCI catalyst) using H2O/TEOS molar ratios of 2.6~59.0, with the EtOH/TEOS ratio fixed. After preparing 9 kinds of sol, the followings were investigated; measurement of the gelation time, thermal analyses by TG/DTA, property analyses of the intermediates by FT-IR and X-ray diffractometry with dried samples, analyses of SiO2 polymer by FT-IR, the investigation of specific sur-face area and pore size distribution by N2-adsorption isotherm, and structural change of SiO2 polymer and pore morphology by TEM observation, with samples heat-treated to 50$0^{\circ}C$. In the concentrations of in-vestigated compositions and catalyst, gelation time showed a minimum at ca. 11 moles of water per one mole of TEOS, the highest degree of polymerization at ca. 8-18 moles, and the largest specific surface area at ca. 11 moles, which means that the polymerization proceeded fastest at ca. 11 moles of water. In con-clusion, the more water used, the faster the polymerization reaction up to ca. 11 moles, but more than ca. 11 moles of water caused retardation of gelation and resultant reduction of specific surface area.

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