• Animal cells and systems
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• 제2권2호
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• pp.229-232
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• 1998

Lysophosphatidylcholine (LPC) has been reported to be responsible for the sustained activation of protein kinase C (PKC). As chondroqenesis is known to be regulated by PKC, this study was performed to investigate the effects of LPC on chondrogenesis of chick limb bud mesenchymes in vitro. LPC treatment of mesenchymes during micromass culture significantly enhanced chondrogenic differentiation. The most effective time of LPC on the stimulation of chondrogenesis was the first day of micromass culture. Analysis of LPC effects on the expression of PKC isoforms revealed that LPC treatment increased expression of PKCa, among the multiple PKC isoforms, in the membrane fraction on day one of culture. The stimulatory effect of LPC on chondrogenesis was abolished if PKCa was down regulated by the prolonged treatment of cells with phorbol ester. The results suqqest that LPC promotes chondrogenesis through the activation of PKCa at the early stage of chondrogenic differentiation.

• Molecules and Cells
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• 제21권2호
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• pp.294-301
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• 2006

We have previously reported that phosphorylation of eukaryotic elongation factor 2 (eEF2) is related to the differentiation of chick embryonic muscle cells in culture. In the present study, we found that eEF2 phosphorylation declined shortly after induction of differentiation of L6 myoblasts, when the cells prepare for terminal differentiation by withdrawing from the cell cycle. This decrease in phosphorylation was prevented by inhibitors of phosphoinositide 3-kinase (PI3-kinase) that strongly inhibit myoblast differentiation. We hypothesized that PI3-kinase plays an important role in myoblast differentiation by regulating eEF2 phosphorylation in the early stages of differentiation. To test this hypothesis, myoblasts were synchronized at in $G_2/M$ and cultured in fresh differentiation medium (DM) or growth medium (GM). In DM the released cells accumulated in $G_0$/$G_1$ while in GM they progressed to S phase. In addition, cyclin D1 was more rapidly degraded in DM than in GM, and eEF2 phosphorylation decreased more. Inhibitors of PI3-kinase increased eEF2 phosphorylation, but PI3-kinase became more activated when eEF2 phosphorylation declined. These results suggest that the regulation of L6 myoblast differentiation by PI3-kinase is related to eEF2 phosphorylation.

• 한국한의학연구원논문집
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• 제4권1호통권4호
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• pp.129-138
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• 1998

Angiogenesis, the formation of new blood vessels, is considered to be involved in many pathological symptoms such as diabetic retinopathy, arthritis, inflammation and solid tumour. In particular, it is thought that angiogenesis is critical for development and growth of solid tumour. Recent study shows that there is a highly significant association of microvessel density with overall survival and relapse-free survival in patients with breast tumour In this study, the inhibition effect of angiogenesis of traditional herbs used for the treatment of cancer was examined. It was found out that the extract of Agaricus blazei by boiling water is a possible inhibitor of angiogenesis. It inhibited normal developmental angiogenesis In the chorioallantoic membrane of chick embryos and also inhibited capillary-like tube formation by endotherial cells on matrigel in vitro. These results suggest that Agaricus blazei can be a potent angiogenesis inhibitor.

• 한국동물위생학회지
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• 제32권1호
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• pp.43-48
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• 2009

Salmonella enterica serovar Gallinarum is the causative agent of fowl typhoid (FT) and Salmonella enterica serovar Pullorum is pullorum disease (PD), a severe systemic disease of chick and it has the same antigenic fomula, the close relation but distinct pathogen. The traditional bacteriologic and serologic methods routinely used but tedious, time consuming. some of biochemical differences are helpful in differentiating the two organisms, however variation in the characteristics of some strains can be observed. During 2006 to 2008, there was isolated 30 strains. The biochemical characteristics of S. Gallinarum was nonmotile, fermentation of dulcitol, maltose but positive arginine (6.6%), lysine (83.3%) and arabinose (20.0%). The antimicrobial susceptibility test showed 100% sensitive to amikacin, ampicillin, amoxicillin/clavulanic acid and florfenicol, but resistant to penicillin (100%) and erythromycin (60.0%). This PCR method can be applied in the diagnosis between S. Gallinarum and S. Pullorum.

• Parasites, Hosts and Diseases
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• 제46권3호
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• pp.165-169
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• 2008

Microphallus species occur primarily as intestinal parasites of birds and mammals, and metacercariae of a new species belonging to this genus have been discovered from the crab, Macrophthalmus dilatatus, in the Republic of Korea. The metacercaria of this fluke was round with 2 thick walls, and the excysted one had mature genital organs. The adult flukes recovered from experimentally infected chicks had numerous intrauterine eggs, well-developed pars prostatica, widely bifurcating ceca, and prominent uterine bulge. After observing internal structures, it was concluded that this species is different from any other known Microphallus spp. Based on the morphology of metacercariae and adult flukes, we describe this specimen as a new species, Microphallus koreana n. sp.

• Bulletin of the Korean Chemical Society
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• 제9권1호
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• pp.55-59
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• 1988

The gaseous carbon dioxide has been irradiated with Co-60 gamma-radiation in the presence and absence of various alcohols, and the radiolysis products analyzed by gas chromatography. Experimental results indicate that no detectable amount of carbon monoxide is formed when pure carbon dioxide is irradiated. By adding small quantities of alcohols to carbon dioxide, however, considerable amount of carbon monoxide, ketones, alcohols and other organic products have been detected. By adding 0.1% of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-methyl-l-propanol, 2-butanol, and 2-methyl-2-propanol, G(CO) values obtained are 4.4, 4.5, 5.2, 4.4, 5.2, 5.0, 4.7 and 4.1, respectively. These high yields of carbon monoxide suggest that the oxidation reactions of carbon monoxide may be suppressed by scavenging oxygen atom with the alcohols. The main radiolytic decomposition reactions of the alcohols present in small quantity in carbon dioxide may be supposed to be the reactions with the oxygen atom produced by the radiolysis of carbon dioxide. The decomposition reactions seems to follow pseudo-first order kinetics with respect to the alcohols. The decomposition rate measured with 2-propanol is the fastest and that with 2-methyl-2-propanol the slowest. The mechanisms of the radiolytic decomposition reactions of the alcohols present in carbon dioxide are discussed on the basis of the experimental results of the present study.

• Nuclear Engineering and Technology
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• 제14권2호
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• pp.70-77
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• 1982

전자선을 이용하여 저밀도 폴리에틸렌을 가교시킬때의 삼관능성 단위체와 산화방지제의 효과를 검토하였다. 가교촉진제로서는 삼관능성 단량체인 Trimethylolpropane triacrylate(TMPTA), Trimethylolpropane trimethacrylate(TMPTM)과 Triallyl cyanurate(TAC)가 사용되었고, 산화방지제로서는 Irganox 1010(Pentaerythritol-tetrakist[3-(3,5-di-t-butyl-4-hydroxyphenyl)-propionate]), Santo-nox R(4,4'-Thio-bis(3-methyl-6-t-butylphenol)), Nocrac D(N-phenyl-$\beta$-naphthylamine)와 Bisphenol A(4,4'-Iso-propylidene bisphenol)가 사용되었다. 삼관능성 단위체중에서 TMPTA가 폴리에틸렌의 가교도를 제일 크게 높였으며 또한 산화안정성도 부여했다. 산화방지제중에서 Nocrac D가 폴리에틸렌에 가장 적당한 것으로 나타났다.

• 동남아시아연구
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• 제22권2호
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• pp.171-199
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• 2012

Saman, a novel written by Ayu Utami, has been recognized as the symbol of the politico-social changes, which began to occur since the collapse of Suharto' New Order regime in 1998. In the novel, Ayu Utami showed the spirits of resistance against various absurd socio-political circumstances during the New Order era such as pressure on discussion, abuse of power, politics-business collusion, patriarchism, and suppression of gender. In representing those spirits, Ayu Utami used unconventional structure-making, fresh feedback and multilayered descriptions of the figures, which brought her a fame as the pioneer of the Fragrant Literature (Angkatan Wangi or chick-lit). Ayu Utami particularly criticized that, under the name of sustaining the national integrity and identity, the New Order regime enhanced patriarchal system, which consequently infringed gender equality and women's rights to self-determination. In addition, Ayu Utami argued that the abuse of power and politics-business collusion, which were prevalent during the New Order period, destroyed lives of the masses and the Indonesian society.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.202.4-203
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• 2003

The present study was carried out to clarify whether isoflavonoids isolated from Belamcandae Rhizoma (Iridaceae) inhibit inflammation and angiogenesis by the experimental methods in vitro and in vivo. Among the isolated isoflavonoids, such as irigenin, irisflorentine, and iristectorene B inhibited nitric oxide (NO) production, as measured by nitrite formation at 3-30 ${\mu}M$. Also these compounds reduced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) enzyme expression in a concentration dependent manner, when measured by western blotting, at 3-30 ${\mu}M$. Irigenin, irisflorentine and iristectoren B decreased angiogenesis of chick embryos in the chorioallantoic membrane assay. These compounds also reduced the proliferation of calf pulmonary arterial endothelial (CPAE) cells and found to possess relatively weak gelatinase/collagenase inhibitory activity in vitro. These compounds, when administered subcataneously at the dose of 30mg/kg for 20 days to mice implanted with murine Lewis lung carcinoma (LLC), caused a significant inhibition of tumor volume. Therefore, antiangiogenic activities of isoflavonoids from Belamcandae Rhizoma might be due to antiproliferative activities under inhibition the induction of COX-2 and iNOS enzyme.

• Nuclear Engineering and Technology
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• 제11권2호
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• pp.119-126
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• 1979

전자선경화성 prepolymer를 합성하기 위해서 4,4'-Dihydroxydiphenyl methane (4,4'-DPM) 과 메타크릴산 글리시딜 (GMA)과의 반응을 염화벤질 트리에틸 암모늄(TEBAC)을 촉매로 하여 진행시키고 그 반응 메카니즘을 고찰하였다. 반응은 3차 속도식 진행시키고 그 반응 메카니즘을 고찰하였다. 반응은 3차 속도식 (equation omitted) 에 해당하였고 활성화 에너지는 33.4kca1/mole 이었다. 그러나 혼합물을 상온에서 24시간 방치한 후의 반응은 빠른 속도로 진행되었다. 촉매효과 및 2,2'-DPM 과 4,4'-DPH의 GMA에 대한 반응성을 비교 검토하였다. 얻어진 데이타를 기초로 하여 가능한 반응기구를 제시하였다.