• 제목/요약/키워드: ${\alpha}_i$-properties

검색결과 385건 처리시간 0.035초

TI-I-174, a Synthetic Chalcone Derivative, Suppresses Nitric Oxide Production in Murine Macrophages via Heme Oxygenase-1 Induction and Inhibition of AP-1

  • Kim, Mi Jin;Kadayat, Taraman;Kim, Da Eun;Lee, Eung-Seok;Park, Pil-Hoon
    • Biomolecules & Therapeutics
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    • 제22권5호
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    • pp.390-399
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    • 2014
  • Chalcones (1,3-diaryl-2-propen-1-ones), a flavonoid subfamily, are widely known for their anti-inflammatory properties. Propenone moiety in chalcones is known to play an important role in generating biological responses by chalcones. In the present study, we synthesized chalcone derivatives structurally modified in propenone moiety and examined inhibitory effect on nitric oxide (NO) production and its potential mechanisms. Among the chalcone derivatives used for this study, TI-I-174 (3-(2-Hydroxyphenyl)-1-(thiophen-3-yl)prop-2-en-1-one) most potently inhibited lipopolysaccharide (LPS)-stimulated nitrite production in RAW 264.7 macrophages. TI-I-174 treatment also markedly inhibited inducible nitric oxide synthase (iNOS) expression. However, TI-I-174 did not significantly affect production of IL-6, cyclooxygenase-2 (COX-2) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), implying that TI-I-174 inhibits production of inflammatory mediators in a selective manner. Treatment of macrophages with TI-I-174 significantly inhibited transcriptional activity of activator protein-1 (AP-1) as determined by luciferase reporter gene assay, whereas nuclear factor-${\kappa}B$ (NF-${\kappa}B$) activity was not affected by TI-I-1744. In addition, TI-I-174 significantly inhibited activation of c-Jun-N-Terminal kinase (JNK) without affecting ERK1/2 and p38MAPK, indicating that down-regulation of iNOS gene expression by TI-I-174 is mainly attributed by blockade of JNK/AP-1 activation. We also demonstrated that TI-I-174 treatment led to an increase in heme oxygenase-1 (HO-1) expression both at mRNA and protein level. Transfection of siRNA targeting HO-1 reversed TI-I-174-mediated inhibition of nitrite production. Taken together, these results indicate that TI-I-174 suppresses NO production in LPS-stimulated RAW 264.7 macrophages via induction of HO-1 and blockade of AP-1 activation.

고잔류자화 $\alpha$-Fe기 Nd-Fe-B 초미세결정립 합금의 자기특성 (Magnetic Properties of $\alpha$-Fe Based Nd-Fe-B Nanocrystalline with High Remanence)

  • 조용수;김윤배;박우식;김창석;김택기
    • 한국자기학회지
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    • 제5권1호
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    • pp.38-41
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    • 1995
  • $\alpha$-Fe를 주상으로 하는 새로운 Nd-Fe-B계 합금을 개발하기 위하여 Nd 함유량을 4at.%로 고정시킨 Nd-Fe-B 초미세결정립합금의 제조 및 자기특성이 조사되었다. 급속응고법으로 제조된 $Nd_{4}Fe_{85.5}B_{10.5}$ 비정질합금은 결정화하여 $\alpha$-Fe 기지상에 $Nd_{2}Fe_{14}B$이 형성되나 자기특성${_{i}H_{c}=95.5kA/m(1.2kOe),\;Br=1.2T}$은 열화된다. Nb 및 Cu를 첨가한 $Nd_{4}Fe_{82}B_{10}Nb_{3}Cu_{1}$ 합금은 $\alpha$-Fe 결정립미세화(<30nm)로 보자력이 207kA/m(2.6 kOe)로 증가하나 잔류자화는 개선되지 않았다. 이 합금조성에 8at.% Co 첨가는 결정립을 더욱 미세화시키며 자기특성을 개선 시킨다. 최적열처리조건에서 $Nd_{4}Fe_{74}Co_{8}B_{10}Nb_{3}Cu_{1}$ 합금의 잔류자화, 보자력 및 최대에너지적이 각각 1.34 T, 219 kA/m (2.75kOe) 및 $95.5kJ/m^{3}$(12MGOe) 이다.

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생물학적 자극 통제 수단으로서 활용하기 위한 돼지 페로몬성 냄새 물질의 탐색: I. 5$\alpha$-androst-16-en-3-one 유사체들의 리간드에 기초한 분자 유사성과 물리화학 파라미터 (The Search of fig Pheromonal Odorants for Biostimulation Control System Technologies: I. Ligand Based Molecular Shape Similarity of 5$\alpha$-androst-16-en-3-one Analogous and Their Physicochemical Parameters)

  • 성낙도;김철호;진동일;박창식
    • Reproductive and Developmental Biology
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    • 제28권1호
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    • pp.45-52
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    • 2004
  • To search a new porcine pheromonal odorants, this research for biostimulation and role of pheromone was augmented by means of "control system technologies" to offer a potentially useful and practical way to improve reproductive efficiency in livestock species. Therefore the 13 physicochemical parameters such as similarity indice (S), hydrophobicity (logP) and van der Waals molecule volume (MV) etc. of 54 steroid analogues, which are analogous of substrate molecules, 5$\alpha$-androst-16-en-3-one (P1) and 5$\alpha$-androst-16-en-3-ol (P2) of lipocalin as receptor of pig pheromones were calculated and discussed. The physicochemical properties of these steroid analogues were mainly followed by steric dissimilar of A and D ring in steroid nucleus. And we found that from correlation with S values and MV constants of molecules, the more MV constants are small, the more S values tend to approach 1. Based on this results, the S-values of 4-androsten-3,17-dione (P1-1) and 5 $\alpha$ -androstan-3-one (P2-1) were 1.0, respectively. The two compounds of them were chosen because they showed the same value each other at a side of hydrophobicity, molar refractivity and molecular volume. It is expected that the new two compounds will be able to substitute for P1 and P2, porcine pheromonal odorants.

Eryngium foetidum Suppresses Inflammatory Mediators Produced by Macrophages

  • Mekhora, Chusana;Muangnoi, Channarong;Chingsuwanrote, Pimjai;Dawilai, Suwitcha;Svasti, Saovaros;Chasri, Kaimuk;Tuntipopipat, Siriporn
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권2호
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    • pp.653-664
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    • 2012
  • Objective: This study assessed anti-inflammatory and antioxidant activities of $E.$ $foetidum$ leaf extract on LPS-activated murine macrophages. Methods: RAW264.7 cells were pretreated with or without $E.$ $foetidum$ extract for 1 h prior to incubation with LPS for 24 h. Anti-inflammatory activity was evaluated with reference to iNOS, COX-2, TNF-${\alpha}$ and IL-6 gene expression. In addition, NO and intracellular ROS generation were determined by Griess method and fluorescence intensity and activation of MAPKs and $I{\kappa}B$ by Western blotting. Results: Prior treatment with $E.$ $foetidum$ leaf extract inhibited elevation of IL-6, TNF-${\alpha}$, iNOS and COX-2, together with their cognate mRNAs in a dose-dependent manner. NO and intracellular ROS contents were similarly reduced. These effects were due to inhibition of LPS-induced phosphorylation of JNK and p38 as well as $I{\kappa}B$. $E.$ $foetidum$ ethanol extract were shown to contain lutein, ${\beta}$-carotene, chlorogenic acid, kaempferol and caffeic acid, compounds known to exert these bioactive properties. Conclusions: $E.$ $foetidum$ leaf extract possesses suppressive effects against pro-inflammatory mediators. Thus, $E.$ $foetidum$ has a high potential to be used as a food supplement to reduce risk of cancer associated with inflammation.

$Al_{71.6}Ge_{28.4}$ 공정합금의 미세구조 및 기계적 성질의 평가 (Microstructural evolution and mechanical properties of $Al_{71.6}Ge_{28.4}$ eutectic alloy)

  • 박진만;육완;김도향
    • 한국주조공학회지
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    • 제27권4호
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    • pp.167-172
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    • 2007
  • In the present study, the microstructural evolution and mechanical properties of $Al_{71.6}Ge_{28.4}$ eutectic alloy have been investigated. Stable (fcc ${\alpha}$-Al and diamond cubic ${\beta}$-Ge) and various metastable crystalline (monoclinic, rhombohedral) phases were produced by competitive phase selection during non-equilibrium processing methods i.e. melt spinning and injection casting. The as-injection casted samples containing metastable-equilibrium eutectic (${\alpha}$-Al + monoclinic) structure showed much higher strength than samples with equilibrium eutectic (${\alpha}-Al+{\beta}-Ge$) structure but plasticity disappointingly diminished. In order to endow the enhanced ductility without significant strength drop, the alloys was heat-treated at transition temperature from metastable phase to stable phase. The annealed specimen displayed the phase transformed microstructural evolution and enhanced macroscopic plasticity.

A new extended alpha power transformed family of distributions: properties, characterizations and an application to a data set in the insurance sciences

  • Ahmad, Zubair;Mahmoudi, Eisa;Hamedani, G.G.
    • Communications for Statistical Applications and Methods
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    • 제28권1호
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    • pp.1-19
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    • 2021
  • Heavy tailed distributions are useful for modeling actuarial and financial risk management problems. Actuaries often search for finding distributions that provide the best fit to heavy tailed data sets. In the present work, we introduce a new class of heavy tailed distributions of a special sub-model of the proposed family, called a new extended alpha power transformed Weibull distribution, useful for modeling heavy tailed data sets. Mathematical properties along with certain characterizations of the proposed distribution are presented. Maximum likelihood estimates of the model parameters are obtained. A simulation study is provided to evaluate the performance of the maximum likelihood estimators. Actuarial measures such as Value at Risk and Tail Value at Risk are also calculated. Further, a simulation study based on the actuarial measures is done. Finally, an application of the proposed model to a heavy tailed data set is presented. The proposed distribution is compared with some well-known (i) two-parameter models, (ii) three-parameter models and (iii) four-parameter models.

Mangiferin isolated from the rhizome of Anemarrhena asphodeloides inhibits the LPS-induced nitric oxide and prostagladin $E_2$ via the $NF-{\kappa}B$ inactivation in inflammatory macrophages

  • Shin, Ji-Sun;Noh, Young-Su;Kim, Dong-Hyun;Cho, Young-Wuk;Lee, Kyung-Tae
    • Natural Product Sciences
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    • 제14권3호
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    • pp.206-213
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    • 2008
  • This study was designed to investigate the anti-inflammatory effects of mangiferin isolated from the rhizome of Anemarrhena asphodeloides, a natural polyphenol, on lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. Mangiferin dose-dependently inhibited LPS-induced nitric oxide (NO) and prostaglandin $E_2\;(PGE_2)$ productions in RAW 264.7 macrophages and peritoneal macrophages isolated from C57BL/6 mice. Consistent with these data, mangiferin suppressed the LPS-induced expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels in a concentration-dependent manner, as determined by Western blotting and RT-PCR, respectively. In addition, the release of tumor necrosis $factor-{\alpha}$($TNF-{\alpha}$) and interleukin-6 (IL-6), and the mRNA expression levels of these cytokines were reduced by mangiferin in a dose-dependent manner. Moreover, mangiferin effectively inhibited the transcriptional activation of nuclear factor-kappa B $(NF-{\kappa}B)$. These results suggest that the anti-inflammatory properties of mangiferin are caused by iNOS, COX-2, $TNF-{\alpha}$, and IL-6 down-regulation due to $(NF-{\kappa}B)$ inhibition in RAW 264.7 macrophages.

Effects of the Essential Oil Components from Ligusticum chuanxiong on Proinflammatory Mediators of RAW264.7 Macrophage Cells

  • Lim, Hye-Rim;Shin, Seung-Won
    • Natural Product Sciences
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    • 제16권4호
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    • pp.259-264
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    • 2010
  • The essential oil fraction was obtained from the underground parts o of Ligusticum chuanxiong (Umbelliferae) by steam distillation, and its main components, Z-ligustilide and butylidene phthalide, were isolated by column chromatography. Its essential oil fraction and the isolated main components were examined for effects on their anti-inflammatory properties in RAW 264.7 macrophage cells to develop a new natural anti-inflammatory drug. The results showed that the L. chuanxiong essential oil fraction and its main components, Z-ligustilide and butylidene phthalide, inhibited the production of nitric oxide significantly in lipopolysaccharide (LPS)-treated RAW 264.7 cells. LPS-induced interleukin-$1{\beta}$ (IL-$1{\beta}$), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-$\alpha$) production was also decreased in a dose-dependent manner. In addition, western blot analysis revealed that the L. chuanxiong essential oil fraction and also its main components, Z-ligustilide, and butylidene phthalide reduced the expression levels of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS).

Influence of Roller Speed on Magnetic Properties and Structures of α-Fe/Nd2Fe14B Nanocomposite Magnets Prepared by Melt-spinning

  • Pei, Wenli;Lian, Fazeng;Fu, Meng;Zhou, Guiqin;Takahashi, M.
    • Journal of Magnetics
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    • 제9권4호
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    • pp.101-104
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    • 2004
  • The crystallization behaviours of nanocomposite made by a function of quenching rate (roller speed) were studied. The results showed that there was one step c$\mathbb{r}$ystallization process for the alloy quenched at roller speed of 32 m/s, which could be shown as, Am (amorphouse) + ${\alpha}-Fe/Nd_2Fe_{14}B$ ${\rightarrow}$ ${\alpha}-Fe/Nd_2Fe_{14}B$ . For the alloy quenched at roller speed of 40 m/s, there was steps crystallization process taking place at different temperatures, which could be shown as, Am ${\rightarrow}$ ${\alpha}-Fe/Nd_2Fe_{23}B_3+Nd_2Fe_{14}B+Am`$ ${\rightarrow}$ ${\alpha}-Fe/Nd_2Fe_{14}B$. The presence of transition phase ($Nd_2Fe_{23}B_3$) was harmful to get fine and uniform grain size during crystallization process. Uniform microstructures and high magnetic properties could be attained for the as-quenched alloy containing less amorphous phase and no presence of transition phase during annealing treatment. For the alloy prepared at roller speed of 32 m/s, the following properties were obtained, $B_r= 0.904 T,_iH_c = 801 kA/m, (BH)_{max} = 122 kJ/m^3 and M_r/M_s = 0.6$.

대두(大豆) 및 Aspergillus niger α-galactosidase의 효소학적(酵素學的) 연구(硏究) (Enzymatic Studies on the α-Galactosidases from Soybean and Aspergillus niger)

  • 금종화;오만진
    • 농업과학연구
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    • 제18권1호
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    • pp.49-73
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    • 1991
  • 발아대두 $\alpha$-galactosidase와 Aspergillus niger가 생산하는 $\alpha$-galactosidase의 효소학적 성질을 비교하기 위하여 대두 발아 중의 $\alpha$-galactosidase활성 및 소당류의 함량변화를 측정하였고, 대두 발아 과정 중 활성이 가장 강할때에 추출한 $\alpha$-galactosidase 및 Aspergillus niger를 밀기울 배양하였을 때 생성되는 $\alpha$-galactosidase를 염석, 이온교환 크로마토그래피 및 겔여과 등을 사용하여 정제한 후 정제효소의 이화학적 및 효소학적 성질을 측정, 비교하여 다음과 같은 결과를 얻었다. 1. 대두 $\alpha$-galactosidase의 활성은 대두를 $25^{\circ}C$에서 120시간 발아시켰을 때 가장 높았으며, 대두 중의 raffinose는 96시간, stachyose는 120시간 발아시켰을 때 완전히 분해되었다. 2. Aspergillus niger를 밀기울배지에서 $30^{\circ}C$, 4일간 배양했을 때 $\alpha$-galactosidase 활성이 최고에 달하였다. 3. 대두 $\alpha$-galactosidase는 황산암모늄 염석, DEAE-Cellulose 및 DEAE-Sephadex A-50 이온교환 크로마토그래피, Sephadex G-l50 겔여과 등에 의하여 6.6배까지 정제되었으며 그의 비활성이 825U/mg protein, 수율 2.5%에 달하였고, Aspergillus niger의 $\alpha$ -galactosidase는 23.7배까지 정제되었으며 그의 비활성이 1,229U/mg protein, 수율 14%에 달하였다. 4. 정제된 대두 및 Aspergillus niger의 $\alpha$-galactosidase는 HPLC, PAGE 및 SDS-PAGE에 의해서 순도가 확인되었다. 5. 정제효소의 이화학적 성질 1) Aspergillus niger의 $\alpha$-galactosidase는 periodic acid schiff 염색에 의하여 당단백질임이 확인되었다. 2) 대두 $\alpha$-galactosidase의 등전점은 pH4.8이었고, 분자량이 30,000인 monomer이었으나, Aspergillus niger의 $\alpha$-galactosidase는 등전점이 pH4.6이었고 분자량은 112,000이었으며 분자량 28,000인 monomer 4개로 구성된 tetramer이었다. 3) 대두 및 Aspergillus niger $\alpha$-galactosidase의 활성에 관여하는 아미노산은 diethyl pyrocarbonate에 의한 화학 수식에 의하여 histidine임이 확인되었다. 4) 대두 $\alpha$-galactosidase의 활성은 2-mercaptoethanol과 L-cysteine에 의하여 약간 저해되었다. 6. 정제효소의 효소학적 성질 1) 대두 $\alpha$-galactosidase의 최적 작용 pH는 pH6.0, 최적 작용온도는 $40^{\circ}C$이었고, Aspergillus niger $\alpha$-galactosidase 각각 pH6.5 및 $40^{\circ}C$이었다. 2) 대두 및 Aspergillus niger의 $\alpha$-galactosidase는 $45^{\circ}C$이하에서 비교적 안정하였으나 $60^{\circ}C$에서 10분 처리시 대두 $\alpha$-galactosidase는 25%, Aspergillus niger $\alpha$-galactosidase는 46%의 잔존활성을 나타내었다. 3) 대두 $\alpha$-galactosidase는 pH5.5~6.5, Aspergillus niger의 $\alpha$-galactosidase는 pH6.0~7.0에서 매우 안정하였다. 4) 대두 및 Aspergillus niger의 $\alpha$-galactosidase간에 기질 특이성상의 차이가 없었으며, stachyose보다 raffinose를 잘 분해하였고, gaIactose는 양효소의 활성을 저해하였다. 5) 대두 $\alpha$-galactosidase의 P-nitrophenyl-$\alpha$-gaIactopyranoside, raffinose 및 stachyose에 대한 Km값은 각각 5.3mM, 50.0mM 및 55.5mM이 었고, Aspergillus niger $\alpha$-galactosidase에 있어서는 각각 5.0mM, 37.0mM 및 55.5mM이었다. 6) 대두 $\alpha$-galactosidase의 p-nitrophenyl-$\alpha$-d-gaIactopyranoside에 대한 활성화 에너지는 13.024Kcal/mole, $Q_{10}$값은 2.0이 었으며, Aspergillus niger의 $\alpha$-galactosidase는 각각 8.515Kcal/mole 및 1.38이었다.

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