• The Korean Journal of Zoology
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• v.36 no.4
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• pp.439-451
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• 1993

Protein kinase C isozymes in a human prostate adenocarcinoma PC-3 cell line were characterized. Immunoreactive bands and immunocytochemical stains were obsenred in PC-3 cells with antibodies raised against protein kinase C ${\alpha}$, ${\beta}$, ${\gamma}$, $\delta$, $\varepsilon$, and ζ types, respectively. Protein kinase C ${\alpha}$ corresponded to a immunoreactive band at a molecular weight of 80,000-dalton, whereas molecular weights of other immunoreactive isozvmes of protein kinase C were detected at 68,000-dalton. Protein kinHse C $\delta$ and ζ antibodies detected additional bands at 55,000-dalton and 80,000-dalton, respectively Immunocvtochemical study confirmed the results of the immunoblotting experiments qualitatively: all six protein kinase C isozymes were detected in the cytoplasm of PC-3 cells. Translocation of protein kinase C in PC-3 cells were also examined with phorbol 12-myristate 13-acetate (PMA), bryostatin 2, diolein, and 1-oleoyl-2-acetyl glycerol (OAG). Differential reactions of protein kinase C isozvmes to these activators were obsenred. When PC-3 cells were treated with 10mM bryostatin 2, protein kinase C isozyme u was translocated into the nucleus, whereas s type was translocated into the plasma membrane and the nucleus. Protein kinase C ${\alpha}$ and ζ types were translocated into the nucleus following the treatment with 101M diolein, whereas protein kinase C ${\alpha}$, ${\beta}$, ${\gamma}$, and $\varepsilon$ types were translocated into the nucleus by the treatment with 10mM OAG. Protein kinase C ${\alpha}$ and $\varepsilon$ types were translocated into the nucleus in the presence of 100nM PMA. Protein kinase C $\delta$ type was translocated to the nuclear membrane by these activators, however, only PMA-induced translocation was inhibited by protein kinase C inhibitor, 1-(5-isoquinolinesulfonyll-2-methvlpiperazine dihvdrochloride (H7) . H7 inhibited translocation of protein kinase C ${\alpha}$ type induced by PMA, ${\beta}$ type by OAG and s type by PMA and OAG, whereas it did not affect translocations induced by bryostatin and diolein, respectively. These results suggest that there exist six isoformes of protein kinase C (${\alpha}$, ${\beta}$, ${\gamma}$, $\delta$, $\varepsilon$ and ζ types) in PC-3 cells and that each of these isozvmes distinctivelv reacts to bryostatin, diolein, OAG and PMA, in part due to an altered molecular size and conceivably discrete binding site(s).

• The Korea Journal of Herbology
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• v.35 no.4
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• pp.9-16
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• 2020

Objective : To identify the effects of the water extract of Liriope platyphylla tuber (Liriopis tuber, LT) on the activation of astocytes, we investigated the regulatory effects of LT extract on H₂O₂-induced oxidative damage in C6 rat astrocytes. Methods : LT extract was extracted with boiling water. C6 cell line were treated with LT extract at 1, 2, and 3 mg/㎖ or without for 30 min and then stimulated with H₂O₂ at 5 ㎛ for 24 hr. The cell viability was measured by MTT assay. The expression of glial fibrillary acidic protein (GFAP), signal transducer and activator of transcription 3 (STAT3), phospho-STAT3 (pSTAT3), cyclooxygenase (COX-2), Nuclear factor-κB (NF-κB), superoxide dismutase 2 (SOD2), heme oxygenase-1 (HO-1), catalase, Akt, phospho-Akt (p-Akt) phosphoinositide 3-kinases (PI3K), and protein kinase C alpha (PKCα) proteins were determined by Western blot, respectively. GFAP expression was also observed with immunocytochemistry under a fluorescence microscope. Results : LT extract induced cell proliferation in H₂O₂-stimulated C6 cells. LT extract significantly inhibited the expression of GFAP, NF-κB and COX-2 and increased the expression of HO-1 and the phosphorylation of STAT3 in H₂O₂-stimulated C6 cells. LT extract also significantly increased the phosphorylation of Akt and decreased the expression of PKCα in a dose-dependent manner in H₂O₂-stimulated C6 cells. Conclusions : LT extract can regulate H₂O₂-induced activation of astrocytes through inhibiting the expression of NF-κB, COX-2 and regulating Akt / HO-1, STAT3 or PKCα signaling pathway.

• Journal of Life Science
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• v.16 no.4
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• pp.691-698
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• 2006

Phospholipase D (PLD) is known to play an important role in a variety of cells. However, little is known about $CoCl_2-mediated$ PLD signaling. In this study we demonstrated for the first time that $CoCl_2$ stimulates PLD activity and increases expression of cyclooxygenase-2 (COX-2), which is known to mediate inflammatory reaction. $CoCl_2-induced$ PLD activity was assessed by measuring the formation of $[^3H]$ phosphatidylbutanol (PtdBut), the product of PLD-mediated transphosphatidylation, in the presence of 1-butanol. To study mechanism of PLD signaling induced by $CoCl_2$, U87 human glioblastoma cells were stimulated by $CoCl_2$ and regulators of PLD activity induced by $CoCl_2$ were investigated using several inhibitors of signaling proteins. Moreover, PLD activation by $CoCl_2$ increased not only expression of COX-2 protein but also COX-2 promoter activity. In summary, these results suggest that $CoCl_2$ increases expression of COX-2 protein via PLD in human U87 glioblastoma cells.

• The Korean Journal of Physiology
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• v.30 no.1
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• pp.63-76
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• 1996

The aim of present study was to characterize phosphate uptake and to investigate the mechanism for the insulin and insulin-like growth factor(IGF) stimulation of phosphate uptake in primary cultured rabbit renal proximal tubule cells. Results were as follows : 1. The primary cultured proximal tubule cells had accumulated $6.68{\pm}0.70$ nmole phosphate/mg protein in the presence of 140 mM NaCl and $2.07{\pm}0.17$ nmole phosphate/mg protein in the presence of 140 mM KCl during a 60 minute uptake period. Raising the concentration of extracellular phosphate to 100 mM$(48.33{\pm}1.76\;pmole/mg\;protein/min)$ induced decrease in phosphate uptake compared with that in control cells maintained in 1 mM phosphate$(190.66{\pm}13.01\;pmole/mg\;protein/min)$. Optimal phosphate uptake was observed at pH 6.5 in the presence of 140 mM NaCl. Phosphate uptake at pH 7.2 and pH 7.9 decreased to $83.06{\pm}5.75%\;and\;74.61{\pm}3.29%$ of that of pH 6.5, respectively. 2. Phosphate uptake was inhibited by iodoacetic acid(IAA) or valinomycin treatment $(62.41{\pm}4.40%\;and\;12.80{\pm}1.64%\;of\;that\;of\;control,\;respectively)$. When IAA and valinomycin were added together, phosphate uptake was inhibited to $8.04{\pm}0.61%$ of that of control. Phosphate uptake by the primary proximal tubule cells was significantly reduced by ouabain treatment$(80.27{\pm}6.96%\;of\;that\;of\;control)$. Inhibition of protein and/or RNA synthesis by either cycloheximide or actinomycin D markedly attenuated phosphate uptake. 3. Extracellular CAMP and phorbol 12-myristate 13 acetate(PMA) decreased phosphate uptake in a dose-dependent manner in all experimental conditions. Treatment of cells with pertussis toxin or cholera toxin inhibited phosphate uptake. cAMP concentration between $10^{-6}\;M\;and\;10^{-4}\;M$ significantly inhibited phosphate uptake. Phosphate uptake was blocked to about 25% of that of control at 100 ng/ml PMA. 3-Isobutyl-1-methyl-xanthine(IBMX) inhibited phosphate uptake. However, in the presence of IBMX, the inhibitory effect of exogenous cAMP was not significantly potentiated. Forskolin decreased phosphate transport. Acetylsalicylic acid did not inhibit phosphate uptake. The 1,2-dioctanoyl-sn-glycorol(DAG) and 1-oleoyl-2-acetyl-sn- glycerol(OAG) showed a inhibitory effect. However, staurosporine had no effect on phosphate uptake. When PMA and staurosporine were treated together, inhibition of phosphate uptake was not observed. In conclusion, phosphate uptake is stimulated by high sodium and low phosphate and pH 6.5 in the culture medium. Membrane potential and intracellular energy levels are also an important factor fer phosphate transport. Insulin and IGF-I stimulate phosphate uptake through a mechanisms that involve do novo protein and/or RNA synthesis and decrease of intracellular cAMP level. Also protein kinase C(PKC) is may play a regulatory role in transducing the insulin and IGF-I signal for phosphate transport in primary cultured proximal tubule cells.

• Journal of Life Science
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• v.31 no.1
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• pp.1-9
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• 2021

Brown seaweeds have been shown to decrease blood glucose levels and improve insulin sensitivity previously. In this study, we investigated the effect of fucoidan, a complex polysaccharide derived from brown seaweeds, on glucose uptake to improve insulin resistance, and examined its mechanism of action in 3T3-L1 adipocytes. We observed that fucoidan significantly increased glucose uptake and it was related to an increased expression of plasma membrane-glucose transporter 4 (PM-GLUT4) in 3T3-L1 adipocytes. Fucoidan treatment increased the activation of phosphatidylinositol-3-kinase (PI3K) and the phosphorylation of insulin receptor substrate 1 (IRS1tyr) compared with that of the control cells. Fucoidan also promoted the phosphorylation of Akt and protein kinase C (PKC)-λ/ζ compared to that of the control cells. Moreover, fucoidan significantly upregulated acetyl-CoA-carboxylase (ACC) and adenosine monophosphate - activated protein kinase (AMPK) phosphorylation. As a result, translocation of GLUT4 was significantly enhanced in 3T3-L1 adipocytes, which significantly promoted glucose uptake via the PI3K/AMPK pathways. The elevation of glucose uptake by fucoidan was blocked by inhibitor of PI3K and inhibitor of AMPK in 3T3-L1 adipocytes. These findings indicate that fucoidan might ameliorate glucose uptake through GLUT4 translocation to the plasma membrane by activating the PI3K/Akt and AMPK pathways in 3T3-L1 adipocytes. Fucoidan is thought to be of high material value to diabetes treatments and functional foods.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.15 no.2
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• pp.23-36
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• 2005

The main obstacle hindering the wide deployment of identity-based cryptosystem is that the entity responsible for creating the private key has too much power. As a result, private keys are no longer private. One obvious solution to this problem is to apply the threshold technique. However, this increases the authentication computation, and communication cost during the key issuing phase. In this paper, we propose a new effi ient model for issuing multiple private keys in identity-based encryption schemes based on the Weil pairing that also alleviates the key escrow problem. In our system, the private key of a user is divided into two components, KGK (Key Description Key) and KUD(Key Usage Desscriptor), which are issued separately by different parties. The KGK is issued in a threshold manner by KIC (Key Issuing Center), whereas the KW is issued by a single authority called KUM (Key Usage Manager). Changing KW results in a different private key. As a result, a user can efficiently obtain a new private key by interacting with KUM. We can also adapt Gentry's time-slot based private key revocation approach to our scheme more efficiently than others. We also show the security of the system and its efficiency by analyzing the existing systems.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.638-643
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• 2004

소형화된 기계가공시스템은 사용재료의 다양화와 에너지 및 공간의 감소와 같은 장점을 가지고 작고 정밀한 부품을 가공할 수 있는 시스템으로 주목받고 있다. 이러한 시스템이 비록 그 크기가 일반적인 가공시스템에 비해 작지만 정렬 및 조립공정, 기계요소의 불완정성에 의한 기하학적 오차는 여전히 존재한다. 기하학적 오차 평가는 기계시스템의 정밀도를 효과적으로 적은 비용으로 향상시킬 수 있는 오차보정기술을 적용할 수 있는 토대가 된다. 일반적으로, 3 축의 직선축으로 이루어진 공작기계는 21 개의 오차요소를 가진다. 레이져간섭계는 이러한 오차요소를 평가하는데 널리 사용되고 있지만 광학계를 정렬하고 설치하는 데 많은 어려움이 있으며 한번의 설치로 한 개의 오차요소만이 측정 가능하다. 또한, 소형공작기계의 경우, 그 크기로 인해 기존의 레이져 간섭계를 직접적으로 적용할 수 없다. 따라서, 본 연구에서는 소형공작기계를 포함한 소형가공시스템의 기하학적 오차 평가를 위한 새로운 다자유도 측정시스템을 제안하였다. 5 개의 정전용량변위센서를 사용하는 이 시스템을 통해 한 축의 움직임에 따른 5 개의 오차요소를 동시에 측정 가능하다. 균질 변환행렬을 이용한 측정알고리듬을 구성하고 이를 모의시험을 통해 평가하였다. 수학적 모델링을 통해 각 센서의 출력값을 유도하고 이를 이용하여 각 오차요소를 계산하기 위한 식을 유도하였다. 여기서, 단순화된 식을 적용한 경우, 임의의 오차에 대한 측정 알고리듬의 정확도를 평가하였다. 또한, 측정 시스템의 설치시 발생하는 셋업오차에 대한 측정 알고리듬의 민감도 분석을 행하였다. 제안하는 측정 시스템은 구조가 간단하고 고가의 부가장비가 필요치 않다. 또한, 적은 비용으로 구성할 수 있으며 높은 측정 정밀도를 가지고 소형가공시스템에 필요한 오차 평가를 행할 수 있다.가 함유된 계란을 생산하고 섭취하였을 때 특정항체들의 결합을 통해 병원성 미생물의 성장이나 군체를 형성하는 것을 무력화시켜 결과적으로 병원균을 감소시키거나 억제시킨다는 점이다. 오늘날 약물에 내성을 지닌 박테리아의 출현으로 질병감염을 막는데 항생제의 사용효과가 점차 감소하고 있기 때문에 이러한 항생제를 대체할 수 있는 방안으로 계란항체를 이용할 수 있다.한 중공 플랜지 형상의 단조 방법 중 보다 적절한 단조방법인 압조 단조에 있어서 일반적으로 사용되고 있는 SM10C에 대한 유한요소 해석을 수행하였으며, 제품의 형상비에 따라 폴딩 결함의 발생 유무를 검토하고, 폴딩 결함 없이 단조하기 위한 중공 플랜지의 형상한계 비를 제시하였다.도 경미하게 나타났으나, 경련이 나타난 쥐에서는 KA만을 투여한 흰쥐와 구별되지 않았다. 이상의 APT의 항산화 효과는 KA로 인한 뇌세포 변성 개선에 중요한 인자로 작용할 것으로 사료되나, 보다 명확한 APT의 기전을 검색하고 직접 임상에 응응하기 위하여는 보다 다양한 실험 조건이 보완되어야 찰 것으로 생각된다. 항우울약들의 항혈소판작용은 PKC-기질인 41-43 kD와 20 kD의 인산화를 억제함에 기인되는 것으로 사료된다.다. 것으로 사료된다.다.바와 같이 MCl에서 작은 Dv 값을 갖는데, 이것은 CdCl$_{4}$$^{2-}$ 착이온을 형성하거나 ZnCl$_{4}$$^{2-}$ , ZnCl$_{3}$$^{-}$같은 이온과 MgCl$^{+}$, MgCl$_{2}$같은 이온종을 형성하기 때문인것 같다. 한편 어떠한 용리액에서던지 NH$_{4}$$^{+}$의 경

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.84-92
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• 2009

This experiment was investigated the effects of fresh and ginger processed Pinelliae Rhizoma extracts on hair growth activity, and its fractions(chloroform, ethyl acetate and water fractions) obtained from fresh Pinelliae Rhizoma on hair growth activity of the normal and spontaneous alopecia areata model of C57BL/6N mice for 16 days. The results were as follows: In fresh Pinelliae Rhizoma extracts treated group, hair growth effect was observed in whole skin area(100%) all the normal mice in whose hair had been clipped on 16th days. In ginger processed Pinelliae Rhizoma extracts treated group, hair growth effect was observed in whole skin area in 25% of normal mice in whose hair had been clipped on 16th days. But in control group, hair growth effect was observed in a part of whole skin area in 25% of normal mice. In fresh Pinelliae Rhizoma extracts treated group, hair follicles of middle stage of anagen phase was observed and it were grown down to subcutaneous tissue of skin in all the mice on 10th day. But in ginger processed Pinelliae Rhizoma extracts treated group and control group, Most of hair follicles of telogen phase was observed in skin. The treatment of extracts of fresh Pinelliae Rhizoma increased the expression of TGF-$\beta$(146%), IGF(107%), and prolactin(115%) in the skin of normal C57BL/6N mice compared to control group(100%). But expression of placenta lactogen(93%) was decreased in the skin of normal C57BL/6N mice compared to control group(100%). In spontaneous alopecia model, The hair growth activity of fresh Pinelliae Rhizoma extracts treated group(100%) was observed to be strong compared with the control group(20%) on 15th day. Hair growth activity on chloroform fractions of fresh Pinelliae Rhizoma extracts was observed in whole skin area in 75% of normal mice on the 9th day. In water and ethyl acetate fractions, hair growth activity was observed in a part of whole skin in 75% and 25% of normal mice, respectively. but hair growth activity of control group was not observed. After application of fractions of fresh Pinelliae Rhizoma extracts for 10 days, hair follicles of chloroform fraction treated group was observed middle stage of anagen phase and hair follicle were grown down to subcutaneous tissue of skin in all the mice. But hair follicles of initial stage of anagen phase were observed in water and ethyl acetate fractions. Most of hair follicles of telogen phase was observed in skin of control group. These experiments suggest that extracts of fresh Pinelliae Rhizoma may stimulate the topical hair growth activity and its chloroform fractions can be useful for treatment of alopecia areata.

• Korean Journal of Poultry Science
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• v.6 no.1
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• pp.12-23
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• 1979

This experiment was carrid out to investigate the interaction between boilelr strains and nutrition levels, and the performances of four broiler strains such as Han Hyup 603, Hubbard, Anak and Filch when they were fed by four different nutrition levels (High Protein and energy; HP. HE., Medium Protein and energy; MP. ME., Low Protein ana energy; LP. LE., and low protein and energy; LLP. LLE.). The data used in this study were obtained from a total of 1200 broiler type chicks in Poultry Testing Station, Korean Poultry Association from June 16, to August 11, 1978. Differences of all characters among four nutrition levels were significant except viability and carcass rate. HP. HE and MP. ME treatments showed nearly the same performances in body weight, feed efficiency and point, spread but they were significantly superior to those of LP. LE and LLP. LLE. There were not significant differences among four strains in feed efficiency and viability but other characters, body weight, point spread and carcass rate were observed that the performance of the best strain B was significantly superior to strain D but it was not recognized significance compared with strain A, C in tile result of statisticel analysis. In the interaction between strains and nutrition levels, body weight at high and levels showed significantly differences but at low and low nutrition levels were nearly same among four strains. Therefore this study demonstrated that comparision of body weights between strains should be performed at medium nutrition level or above. Also point spread calculated as index of body weight and feed efficiency was observed that strain B at low nutrition level is excellently higher than other strains and there were little differences at low nutrition level among all strains. It was found that ]it tie differences between performances of high arid medium levels seemed to be as the reason of high fat addition for energy source to high mutrition feed, and in general superior strain showed good performance at all the nutrition levels in$.$all characters but in body weight and point spread there were significantly different responses with different nutrition level, The most superior strain B among four strains earned the most profit per bird, Although performances of high and medium nutrition levels were nearly the same, medium nutrition level also showed the most profit because the feed cost of high nutrition level was higher than that of medium nutrition level.

• Composites Research
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• v.12 no.4
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• pp.71-78
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• 1999

To determine the effect of chemical structure of linear amine curing agents on thermal and mechanical properties, standard epoxy resin DGEBA was cured with diaminodiphenyl methane (DDM), diaminodiphenyl sulphone (DDS) in a stoichiometrically equivalent ratio. From this work, the effect of aromatic amine curing agents. In contrast, the results show that the DGEBA/DDS cure system having the sulfone structure between the benzene rings had higher values in the conversion of epoxide, density, shrinkage (%), glass transition temperature, tensile modulus and strength, flexural modulus and strength than the DGEBA/DDM cure system having methylene structure between the benzene rings, whereas the DGEBA/DDM cure system presented higher values in the maximum exothermic temperature, thermal expansion coefficient, and thermal stability. These results are caused by the relative effects of sulfone group having strong electronegativity and methylene group having (+) repulsive property and stem from the effect of the conversion ratio of epoxide group. The result of fractography shows that the each grain size of the DDM/DGEBA system with feather-like structure is larger than that of the DDS/DGEBA system.