• 대한화학회지
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• 제22권1호
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• pp.30-36
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• 1978

25% dioxane 수용액 속에서 ${\alpha}$-nitrobenzaldehydephenylhydrazone의 여러 유도체(p-N$NO_2$,p-Cl, m-$NO_2$, p-$CH_3$)에 대해 pH의 변화에 따르는 가수분해 속도상수를 $25^{\circ}C$에서 자외선 분광광도법으로 측정하여 넓은 pH에서 잘 맞는 반응 속도식을 구하였다. 가수분해 속도에 미치는 치환기효과를 고려하고자 Hammett의 식을 적용한 결과 pH1.0에서는 ${\rho}$=0.18, pH 7.0에서는 ${\rho}$=0.06을 얻었다. pH의 변화에 따르는 반응속도상수의 변화, 용매효과, 치환기효과, 산해리상수 측정 등으로부터 ${\alpha}$-nitrobenzaldehydephenylhydrazone의 가수분해는 pH 3.0 이하에서는 $S_N1$, pH 4.0 이상에서는 1,3-dipole을 거치는 반응이 pH 3.0 과 pH 4.0 사이에서는 이 두 반응이 경쟁적으로 일어남을 알았다.

• 대한의생명과학회지
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• 제12권3호
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• pp.201-208
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• 2006

PI3-kinase activity through p85, the regulatory subunit of class IA PI3-kinase, is indispensable for the growth, differentiation, and survival of skeletal muscle cells, but little is known about the function of other regulatory subunits such as p55 and p50. We examined the subcellular localization and the expression of the regulatory subunits of class IA PI3-kinase in L6 myoblasts. Both p55 and p50 as well as p85 were expressed in L6 myoblasts. Whereas p85 was localized at both cytosolic and nuclear tractions, p55 and p50 were localized at only the nuclear traction. During the differentiation of L6 myoblasts, the protein concentrations of both p55 and p50 were decreased but that of p85 was not significantly changed. Menadione-induced oxidative stress induced the translocation of p85 from cytosol to nucleus and the increase of p55 expression. These results suggest that the regulatory subunits of class IA PI3-kinase play an important role in L6 myoblasts.

• 한국발생생물학회지:발생과생식
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• 제2권2호
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• pp.165-171
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• 1998

p62는 임파구에 특이적으로 발현하는 단백질 티로신 키나제인 p56$^{lck}$의 SH2 doamin과 결합하는 세포질 단백질로서 두 단백질의 결합에는 지금까지 알려진 바와 다르게 인산화된 티로신이 필요없다. p62는 기능이 다른 여러 조직에서 공통적으로 발현되며 유비퀴틴, 단백질 키나제 C 이성질체 둥 다양한 단백질과 결합하는 것이 알려져 있다. 이와 같은 현상으로 p62가 다양한 생물학적 기능을 수행할 수 있음을 예측할 수 있으나 그 자세한 기작은 잘 알려져 있지 않다. 본 연구에서는 p62가 T-세포에 특이적으로 발현하는 14-3-3 $ au$ 이성질체와 결합하는 것을 확인하였으며, p62를 인위적으로 T-세포에 다량으로 발현시키면 세포예정사 (apoptosis)의 시작이 지연되는 현상을 조사하였다. 이때 세포사멸과정에서 전형적으로 나타나는 DNA 절단현상 (DNA fragmentaion)과 poly (ADP-ribose) polymerase의 분해가 지연됨을 알 수 있었다. 최근 14-3-3 단백질이 임파구에서 세포예정사를 촉진시키는 기능을 가진 Bad와 결합함으로써 세포의 생존 신호 전달에 중요한 역할을 한다는 것이 보고된 바 있다. 따라서 본 연구의 결과는 T-세포의 활성으로 일어나는 사멸예정사 과정 중에 p62와 14-3-3 단백질에 의해 수행되는 조절 기작이 있음을 시사하고 있다.다.

• Journal of Nutrition and Health
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• 제33권2호
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• pp.124-133
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• 2000

This study evaluated the effects of chronic ethanol consumption and/or taurine supplementation on hepatic total, phospholipid fatty acid composition and the metabolism of rats fed one of three purified liquid diets for 8 weeks. the rats followed either the control diet (CD, ethanol-free and taurine-free diet); ethanol diet (ED, CD+ 50g ethanol/L) or ethanol-taurine diet (ETD, ED+3.75g taurne/L). Chronic ethanol consumption and/or dietary taurine supplementation were associated with altered hepatic total and phospholipid fatty acid composition. compared to the values for the control rats, ED or ETD significantly decreased the percentage of total monounsaturated fatty acids ($\Sigma$MUFA), and increased the percentage of total polyunsaturated fatty acids ($\Sigma$PUFA) of hepatic total lipids(p〈0.01). Percentages of 14:0(P〈0.01) and 16:0(p〈0.001) were sigificantly lower, and those of 18:0(p〈0.01), 20:0(p〈0.001), 20:3$\omega$6(p〈0.01) and 22:4$\omega$6(p〈0.01) in hepatic total fatty acid compositions were oserved in rats fed ETD versus those fed ED or ETD. No significant differences in hepatic total fatty acid compositions were observed in rats fed ETD versus those fed ED. Percentages of 24:0(p〈0.01), 16:1(p〈0.05), 20:1(p〈0.01), 18:2$\omega$6(p〈0.01) and 18:3$\omega$3(p〈0.05) in hepati phospholipids were significantly higher, and those of 14:0(p〈0.01), 16:0(p〈0.001), 20:3$\omega$3(p〈0.05) in hepatic phospholipids were significantly higher, and those of 14:0(p〈0.01), 16:0(p〈0.001), 20:3$\omega$3(p〈0.001), 22:6$\omega$3(p〈0.001) and $\Sigma$$\omega$3(P〈0.001) were significantly lower in rats fed ED or ETD compared to the values for the control rats. The Δ5 desaturation index(20:3$\omega$6⇒20:4$\omega$6) and elongation index (20:5$\omega$3⇒22:5$\omega$3) of hepatic phospholipid index (20:3$\omega$6⇒20:4$\omega$6) and decreased Δ4 desaturation index (22:5$\omega$3⇒22:6$\omega$3) compared to the values for the ED rats. These changes in hepatic fatty acid composition induced by chronic ethanol consumption and/or taurine supplementation might be associated with the modulations of physical properties of the hepatic cell membrane and its sensitivity to peroxidation damage.

• 한국전기전자재료학회논문지
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• 제22권2호
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• pp.107-113
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• 2009

In order to improve air stability, we proposed a new active layer of an organic TFT by synthesizing P3HT/POSS conjugated polymer. P3HT/POSS OTFTs with the various P3HT/POSS volume ratios were fabricated and characterized. With the P3HT/POSS volume ratio of 1:1, we achieved the field-effect mobilities of ${\sim}1.19{\times}10^{-3}\;cm^2/v{\cdot}sec$ in the saturation region and the current on/off ratio of ${\sim}2.51{\times}10^2$. The resulting current on-off ratio was much higher than that of the P3HT-based OTFTs and resulted from the dramatic decrease of the off-current. Since the off-current can be reduced by preventing oxygen in atmosphere from doping the P3HT/POSS active layers, this new active layer shows its ability to avoid oxygen doping in atmosphere. Therefore, the improvement of the air stability can be achieved by employing the P3HT/POSS active layers.

• 산업기술연구
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• 제20권A호
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• pp.45-50
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• 2000

A submerged cultivation of Ganoderma lucidum was carried out in an air-lift fermenter system, and the effects of different pH processes on extracellular branched ${\beta}$-1,3-glucan(EPS) production and mycelial growth(MDW) were investigated. The controlled pH process improved the production of branched ${\beta}$-1,3-glucan and biomass in comparison to the uncontrolled pH process. However, the maximum production of branched ${\beta}$-1,3-glucan were obtained by the bi-staged pH process. From these results, we confirmed that the bi-staged pH process was the most effective for improving the production of branched ${\beta}$-1,3-glucan from submerged culture of G. lucidum.

• 공업화학
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• 제3권2호
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• pp.189-193
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• 1992

The success of 3M's worldwide Pollution Prevention Pays (3P) Program convinced 3M's top management that the program should be expanded into a comprehensive environmental management system called 3P Plus. The emphasize of the 3P Plus program is to continually minimize the environmental impact of 3M processes, products, and operations to include energy management, resource recovery, and other initiatives. 3M's experience with the 3P and 3P Plus programs will be described. 3M's experience can serve as a model for other multi-national companies interested in sustainable development and economic growth with environmental protection.

• Asian-Australasian Journal of Animal Sciences
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• 제13권5호
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• pp.659-665
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• 2000

A nitrogen (N) balance trial was conducted to examine the effect of N deprivation on subsequent N retention, blood urea nitrogen (BUN) and IGF-I levels and the ratio of IGF binding protein (IGFBP)-3 to IGFBP-l and -2. Pigs in treatment (T) 1 were given diet A (2.39% N) and those in T2 and T3 were given diet B (1.31% N) and excreta were collected (period 1 (P1)). Pigs in T1 continued to receive diet A while diets for T2 and T3 were changed to diets A and C (2.74% N), respectively. The excreta were collected for two more periods (P2 and P3). During P1, pigs in T2 and T3 retained 50% less N (p<0.001) than those in T1. However, pigs provided T2 (p<0.01) and T3 (p<0.05) retained more N than those assigned to T1 during P2. Pigs in T3 tended to retain more (p=0.10) N than those receiving T2 for the same period. The BUN values were lower (p<0.05) for pigs assigned to T2 and T3 than T1 during P1 and P2. Both IGF-I and IGFBP ratios of pigs assigned to T1 were higher (p<0.05) than those given T2 and T3 during P1 but no differences were found during P2 and P3.

• 생명과학회지
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• 제31권11호
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• pp.995-1003
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• 2021

크로마틴 리모델링은 후성유전기전을 통해 유전자 발현을 조절한다. 비정상적인 히스톤 변형이 우울증 발생에 관여하는 것으로 알려져 있다. p11 (S100A10)은 인간과 설치류에서 우울증의 병태생리에 관여한다고 보고되었다. 본 연구는 우울증 동물모델인 장기간 예측 불가능한 스트레스가 마우스 해마에서 p11 유전자 promoter의 히스톤 변형에 미치는 영향을 조사하고자 하였다. C57BL/6 마우스에 21일 동안 스트레스를 가하고, 강제수영검사를 수행하여 우울 유사 행동 양상을 측정하였다. Real time PCR 및 Western blotting 분석법으로 p11 발현 변화를 조사하였으며, 염색질 면역침전분석법을 수행하여 p11 promoter의 히스톤 H3 아세틸화 및 메틸화 양을 측정하였다. 장기간 예측 불가능한 스트레스는 강제수영검사에서 부동시간을 증가시켜 우울 유사 행동을 나타내었으며, 해마의 p11 mRNA 및 단백질 발현을 유의하게 감소시켰다. 또한 p11 promoter의 히스톤 H3 아세틸화(Ac-H3) 및 H3-K4 트리메틸화(H3K4met3)를 유의하게 감소시켰으며, H3-K27 트리메틸화(H3K27met3)를 증가시켰다. 본 연구결과는 만성 스트레스가 해마에서 p11 유전자의 후성유전적 억제를 야기하여 p11 유전자의 발현을 감소시킴을 시사한다.

• Molecules and Cells
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• 제45권3호
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• pp.122-133
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• 2022

The aim of this study was to investigating whether lncRNA H19 promotes myocardial fibrosis by suppressing the miR-29a-3p/miR-29b-3p-VEGFA/TGF-β axis. Patients with atrial fibrillation (AF) and healthy volunteers were included in the study, and their biochemical parameters were collected. In addition, pcDNA3.1-H19, si-H19, and miR-29a/b-3p mimic/inhibitor were transfected into cardiac fibroblasts (CFs), and proliferation of CFs was detected by MTT assay. Expression of H19 and miR-29a/b-3p were detected using real-time quantitative polymerase chain reaction, and expression of α-smooth muscle actin (α-SMA), collagen I, collagen II, matrix metalloproteinase-2 (MMP-2), and elastin were measured by western blot analysis. The dual luciferase reporter gene assay was carried out to detect the sponging relationship between H19 and miR-29a/b-3p in CFs. Compared with healthy volunteers, the level of plasma H19 was significantly elevated in patients with AF, while miR-29a-3p and miR-29b-3p were markedly depressed (P < 0.05). Serum expression of lncRNA H19 was negatively correlated with the expression of miR-29a-3p and miR-29b-3p among patients with AF (r_s = -0.337, r_s = -0.236). Moreover, up-regulation of H19 expression and down-regulation of miR-29a/b-3p expression facilitated proliferation and synthesis of extracellular matrix (ECM)-related proteins. SB431542 and si-VEGFA are able to reverse the promotion of miR-29a/b-3p on proliferation of CFs and ECM-related protein synthesis. The findings of the present study suggest that H19 promoted CF proliferation and collagen synthesis by suppressing the miR-29a-3p/miR-29b-3p-VEGFA/TGF-β axis, and provide support for a potential new direction for the treatment of AF.