• Title/Summary/Keyword: Crossover study

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Comparative Bioavailability and Metabolism of Two Capsule Formulations of Fluoxetine in Human Volunteers (플루옥세틴 캅셀제의 지원자에 대한 생체이용율 및 대사율 비교)

  • Kang, Won-Ku;Park, Yong-Soon;Cho, Gyu-Haeng;Choi, Jun-Sik;Kwon, Kwang-Il
    • YAKHAK HOEJI
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    • v.42 no.5
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    • pp.513-518
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    • 1998
  • Fluoxetine is a nontricyclic antidepressant which blocks serotonin reuptake selectively. Its N-demethyl metabolite, norfluoxetine is also selective inhibitor of serotonin uptake . This study was carried out to compare the bioavailability of Myung-in fluoxetine (20mg/cap.) with that of Prozac$^{\circde{R}}$. The bioavailability was conducted on 24 healthy volunteers who received a single dose (80mg) of each drug in the fasting state, in a randomized balanced 2-way crossover design. After closing, serial blood samples were collected for a period of 48 hours, Plasma was analyzed for fluoxetine and norfluoxetine by a sensitive and validated HPLC assay. The major pharmacokinetic parameters ($AUC_{0-48\;hr}$, Cmax, Tmax , $AUC_{inf.}$, MRT. $T_{1/2}$, Vd and Cl) were, calculated from the plasma fluoxetine concentration-time data of each volunteer. The microcomputer program, 'WinNonlin' was used for compartmental analysis. A two-compartment model with first-order input, first-order output and no lag time was chosen as the most appropriate pharmacokinetic model. The data were best described by using a weighting factor of $1/y^2$. Though the plasma fluoxetine concentrations of Myung-in fluoxetine were higher than those of Prozac$^{\circde{R}}$ at all observed time from 7.9% to 16.9% (P<0.05 at 6.7 and 10 hr), the bioavailability of Myung-in fluoxetine appeared to be bioequivalent with that of Prozac$^{\circde{R}}$. There were no statistical significant differences between the two drugs in all pharmacokinetic parameters including $AUC_{0-48\;hr}$ of norfluoxetine.

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Development of a Lightweight 200W Direct Methanol Fuel Cell Stack for UAV Applications and Study of its Operating Characteristics (II) (무인항공기용 200W 급 직접메탄올연료전지 경량화 스택 제작 및 작동 특성 연구 (II))

  • Kang, Kyung-Mun;Park, Sung-Hyun;Gwak, Geon-Hui;Ji, Hyun-Jin;Ju, Hyun-Chul
    • Transactions of the Korean hydrogen and new energy society
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    • v.23 no.3
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    • pp.243-249
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    • 2012
  • A lightweight 200W direct methanol fuel cell (DMFC) stack is designed and fabricated to power a small scale Unmanned Aerial Vehicle (UAV). The DMFC stack consists of 33-cells in which membrane-electrode assemblies (MEAs) having an active area of 88 $cm^2$ are sandwiched with lightweight composite bipolar plates. The total stack weight is around 3.485 kg and stack performance is tested under various methanol feed concentrations. The DMFC stack delivers a maximum power of 248 W at 13.2 V and $71.3^{\circ}C$ under methanol feed concentration of 1.2 M. In addition, the voltage of individual cell in the 33-cell stack is measured at various current levels to ensure the stability of DMFC stack operations. The cell voltage distribution data exhibit the maximum cell voltage deviation of 28 mV at 15 A and hence the uniformity of cell voltages is acceptable. These results clearly demonstrate that DMFC technology becomes a potential candidate for small-scale UAV applications.

Characteristics of Poly(arylene ether sulfone) Membrane for Proton Exchange Membrane Fuel Cells (고분자전해질 연료전지용 Poly(arylene ether sulfone) 막의 특성)

  • Jeong, Jae-Jin;Shin, Yong-Cheol;Lee, Moo-Seok;Lee, Dong-Hoon;Na, Il-Chai;Lee, Ho;Park, Kwon-Pil
    • Korean Chemical Engineering Research
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    • v.51 no.5
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    • pp.556-560
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    • 2013
  • Recently, there are many efforts focused on development of more economical non-fluorinated membranes for use in PEMFCs (Proton Exchange Membrane Fuel Cells). In this study, characteristics of poly(arylene ether sulfone)(PAES) were compared with fluorinated membrane at PEMFC operation condition. I-V polarization curve, hydrogen crossover, electrochemical surface area, membrane resistance and charge transfer resistance were measured. PAES membrane showed similar performance compared with fluorinated membrane at 100% relative humidity, but the performance of PAES membrane decreased largely due to low ionic conductivity at low relative humidity.

Development of succinate producing Cellulomonas flavigena mutants with deleted succinate dehydrogenase gene

  • Lee, Heon-Hak;Jeon, Min-Ki;Yoon, Min-Ho
    • Korean Journal of Agricultural Science
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    • v.44 no.1
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    • pp.30-39
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    • 2017
  • This study was performed to produce succinic acid from biomass by developing mutants of Cellulomonas flavigena in which the succinate dehydrogenase gene (sdh) is deleted. For development of succinate producing mutants, the upstream and downstream regions of sdh gene from C. flavigena and antibiotic resistance gene (neo, bla) were inserted into pKC1139, and the recombinant plasmids were transformed into Escherichia coli ET12567/pUZ8002 which is a donor strain for conjugation. C. flavigena was conjugated with the transformed E. coli ET12567/pUZ8002 to induce the deletion of sdh in chromosome of this bacteria by double-crossover recombination. Two mutants (C. flavigena H-1 and H-2), in which sdh gene was deleted in the chromosome, were constructed and confirmed by PCR. To estimate the production of succinic acid by the two mutants when the culture broth was fermented with biomass such as CMC, xylan, locust gum, and rapeseed straw; the culture broth was analyzed by HPLC analysis. The succinic acid in the culture broth was not detected as a fermentation products of all biomass. One of the reasons for this may be the conversion of succinic acid to fumaric acid by sdh genes (Cfla_1014 - Cfla_1017 or Cfla_1916 - Cfla_1918) which remained in the chromosomal DNA of C. flavigena H-1 and H-2. The other reason could be the conversion of succinyl-CoA to other metabolites by enzymes related to the bypass pathway of TCA cycle.

Pharmacokinetics and Bioequivalence of Haloperidol Tablet by Liquid Chromatographic Mass Spectrometry with Electrospray Ionization

  • Yun Min-Hyuk;Kwon Jun-Tack;Kwon Kwang-il
    • Archives of Pharmacal Research
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    • v.28 no.4
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    • pp.488-492
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    • 2005
  • The purpose of this study is to investigate the bioequivalence of two haloperidol 5 mg tablets, Myung In haloperidol (Myung In Pharm. Co., Ltd., test drug) and $Peridol^{R}$(Whanin Pharm. Co., Ltd., reference drug), and also to estimate the pharmacokinetic parameters of haloperidol in Korean volunteers. The bioavailability and pharmacokinetics of haloperidol tablets were examined on 24 healthy volunteers who received a single oral dose of each preparation in the fasting state in a randomized balanced 2 way crossover design. After an oral dosing, blood samples were collected for a period of 60 h. Plasma concentrations of haloperidol were determined using a liquid chromatographic electrospray mass spectrometric (LC-MS) method. The pharmacokinetic parameters were calculated with noncompartmental pharmacokinetic analysis. The geometric means of $AUC_{0-60h} and C_{max}$ between test and reference formulations were $17.21\pm8.26 ng\cdot/mL vs 17.31\pm13.24 ng\cdot/mL and 0.87\pm0.74 ng/mL vs 0.85\pm0.62 ng/mL$. respectively. The $90\%$ confidence intervals of mean difference of logarithmic transformed $AUC_{0-60h} and C_{max} were log0.9677{\sim}log1.1201 and log0.8208{\sim}log1.1981$, respectively. It shows that the bioavailability of test drug is equivalent with that of reference drug. The geometric means of other pharmacokinetic parameters ($AUC_{inf}. t_{1/2}, V_{d}/F, and CL/F$) between test drug and reference drug were $21.75\pm8.50 ng{\cdot}h/mL vs 21.77\pm15.63 ng{\cdot}h/mL, 29.87\pm8.25 h vs 29.60\pm7.56 h, 11.51\pm5.45 L vs 12.90\pm6.12 L and 0.26\pm0.09 L/h vs 0.31\pm0.17 L/h$, respectively. These observations indicate that the two formulation for haloperidol was bioequivalent and, thus, may be clinically interchangeable.

Bioequivalency on the Comparative Bioavailability of Two Capsule Formulations of Cefixime in Human Volunteers (지원자의 Cefixime캅셀제 생체이용율에 대한 생물학적동등성 연구)

  • Kang, Won Ku;Woo, Jong Su;Kwon, Kwang Il
    • Korean Journal of Clinical Pharmacy
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    • v.8 no.1
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    • pp.19-22
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    • 1998
  • Cefixime is an orally absorbed 3rd generation cephalosporin with a broad spectrum of activity against Gram-positive and Gram-negative bacteria and is highly resistant to $\beta-lactamase$ degradation. This study was carried out to evaluate the bioavailability of a new test drug of cefixime (100 mg/capsule) relative to the reference drug. The bioavailability was conducted on 20 healthy volunteers who received a single dose (400 mg) of the test and the reference drugs in the fasting state, in a randomized balanced 2-way crossover design. After dosing, serial blood samples were collected for a period of 12 hours. Plasma was analyzed for cefixime by a sensitive and validated HPLC assay. The major pharmacokinetic parameters $(AUC_{0-12hr},\;C_{max},\;T_{max})$ were calculated from the plasma concentration-time data of each volunteer. The $AUC_{0-12hr},\;C_{max}\;and\;T_{max}$ of the test drug were $36.91\pm11.85\;{\mu}g{\cdot}hr/ml,\;5.47\pm1.61\;{\mu}g/ml,\;and\;4.00\pm0.65\;hr,$ respectively, and those of the reference drug were $34.08\pm8.81\;{\mu}g{\cdot}hr/ml,\;5.25\pm1.40\;{\mu}g/ml,\;and\;4.20\pm0.62\;hr$, respectively. Mean differences of those parameters were 8.32, 4.29, and $4.76\%$, respectively, and the least significant differences at $\alpha$=0.05 for $AUC_{0-12hr},\;C_{max},\;T_{max}$ were 16.02, 13.78, and $11.76\%$, respectively. In conclusion, the test drug was bioequivalent with the reference drug.

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Characteristics of Proton Exchange Membrane Fuel Cells(PEMFC) Membrane and Electrode Assembly(MEA) Using Sulfonated Poly(ether ether ketone) Membrane (sPEEK 막으로 제조한 고분자전해질 연료전지(PEMFC) 막전극합체(MEA)의 특성)

  • Lee, Hye-Ri;Lee, Se-Hoon;Hwang, Byung-Chan;Na, Il-Chai;Lee, Jung-Hun;Oh, Sung-June;Park, Kwon-Pil
    • Korean Chemical Engineering Research
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    • v.54 no.2
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    • pp.181-186
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    • 2016
  • Recently, there are many efforts focused on development of more economical non-fluorinated membranes for use in PEMFCs (Proton Exchange Membrane Fuel Cells). In this study, characteristics of sulfonated Poly(ether ether ketone) (sPEEK) were compared according to degrees of sulfonation (DS), relative humidity, cell temperatures at PEMFC operation condition. I-V polarization curve, hydrogen crossover, electrochemical surface area, membrane resistance and charge transfer resistance were measured. sPEEK membrane showed high performance at high DS, high temperature and high relative humidity, in particular, performance of sPEEK membrane decreased largely due to low ionic conductivity at low DS and low relative humidity.

Open Channel Block of Kv3.1 Currents by Genistein, a Tyrosine Kinase Inhibitor

  • Choi, Bok-Hee;Park, Ji-Hyun;Hahn, Sang-June
    • The Korean Journal of Physiology and Pharmacology
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    • v.10 no.2
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    • pp.71-77
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    • 2006
  • The goal of this study was to analyze the effects of genistein, a widely used tyrosine kinase inhibitor, on cloned Shaw-type $K^+$ currents, Kv3.1 which were stably expressed in Chinese hamster ovary (CHO) cells, using the whole-cell configuration of patch-clamp techniques. In whole-cell recordings, genistein at external concentrations from 10 to $100{\mu}M$ accelerated the rate of inactivation of Kv3.1 currents, thereby concentration-dependently reducing the current at the end of depolarizing pulse with an $IC_{50}$ value of $15.71{\pm}0.67{\mu}M$ and a Hill coefficient of $3.28{\pm}0.35$ (n=5). The time constant of activation at a 300 ms depolarizing test pulses from -80 mV to +40 mV was $1.01{\pm}0.04$ ms and $0.90{\pm}0.05$ ms (n=9) under control conditions and in the presence of $20{\mu}M$ genistein, respectively, indicating that the activation kinetics was not significantly modified by genistein. Genistein $(20{\mu}M)$ slowed the deactivation of the tail current elicited upon repolarization to -40 mV, thus inducing a crossover phenomenon. These results suggest that drug unbinding is required before Kv3.1 channels can close. Genistein-induced block was voltage-dependent, increasing in the voltage range $(-20\'mV{\sim}0\'mV)$ for channel opening, suggesting an open channel interaction. Genistein $(20{\mu}M)$ produced use-dependent block of Kv3.1 at a stimulation frequency of 1 Hz. The voltage dependence of steady-state inactivation of Kv3.1 was not changed by $20{\mu}M$ genistein. Our results indicate that genistein blocks directly Kv3.1 currents in concentration-, voltage-, time-dependent manners and the action of genistein on Kv3.1 is independent of tyrosine kinase inhibition.

Analysis of Convergence Factors of Preschool children's Parenting and Health Characteristics on Economic Participation (미취학 아동 어머니의 양육특성과 건강 특성이 경제활동 참가에 미치는 융합적 요인 분석)

  • Kim, Seong Min;Song, Hye-young
    • Journal of the Korea Convergence Society
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    • v.12 no.9
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    • pp.285-293
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    • 2021
  • This study is a second analysis of the 7th Korean Longitudinal Survey of Women and Families. And, it is a descriptive survey research for comparing parental and health characteristics of 2 groups of workers and non-workers. For this, it has used crossover analysis and logistic regression analysis with the subjects of mothers of preschoolers - of 697 females in total, aged between 19 and 64. Based on the result of the logistic regression analysis, we have discovered a few factors inducing the females to participate in more economic activities. The factors are as follows : baby sitters available, the more number of child care centers, the more helps of baby sitting from the females' parents and in-law parents and physical activities less than 3 times a week. In contrast, however, the more preschoolers they have, the less likely they are to take an active part in the economy. Against the backdrop, the government should develop social service systems to encourage various child care services and to foster 'child raising mothers-friendly' environments not only in families but in workplaces. All this is to improve the health characteristics of preschoolers' mothers in a more healthy way' and to strike a balance between work and family.

Analysis Of The Average Rate Of Change And Curvature According To The Type Of Angled And Arched Eyebrow Makeup (각진형과 아치형 눈썹메이크업의 평균변화율 및 곡률에 따른 형태구성의 중요요인 분석)

  • Park, Jeong Shin;Park, Dong Eun
    • Journal of Fashion Business
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    • v.23 no.1
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    • pp.116-126
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    • 2019
  • The purpose of this study is to objectify the shape of curvature and average change rate of angular and arched eyebrow makeup. The data for the analysis were the final 336 pieces for the cosmetology students in the whole country. SPSS 20.0 program was used for the collected data, frequency analysis, factor analysis, reliability analysis, and crossover analysis were performed. First, the frequency of the average change rate of eyebrow makeup (angular and arcuate) was analyzed. As a result, the eyebrows suitable for the angled type showed the highest level of 'A-2' and the arched eyebrows had the highest level of 'B-2'. Second, to analyze the important factors of eyebrow makeup, frequency of eyebrows was the most important, followed by the inclination of eyebrows and eyebrow tail. Third, factor analysis and reliability analysis were conducted to examine each dimension of eyebrow makeup perception, and it was derived from three factors including acceptability, aggressiveness, and playability. Fourth, in order to analyze the difference of important factors in the form of the standard eyebrow makeup, the cross - analysis was performed with chi - square test, and it was confirmed that the angular eyebrow makeup showed the most objectivity when the average change rate was 0.29 and the curvature was 0.67. Fifth, arcuate eyebrow makeup showed the most objectivity when the average change rate was 0.57 and curvature was 0.56. The results of this analysis can be used as objective data of aesthetic criteria when designing the eyebrow shape.