• Title/Summary/Keyword: $\mu$ synthesis

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A study on Synthesis and Radiation Detector Fabrication of Thin Films by MW Plasma CVD (MWPECVD에 의한 박막의 합성과 방사선 검출 특성에 관한 연구)

  • Koo, Hyo-Geun;Lee, Duck-Kyu;Song, Jae-Heung;Noh, Kyung-Suk;Park, Sang-Hyun
    • Journal of radiological science and technology
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    • v.27 no.2
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    • pp.45-50
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    • 2004
  • Synthesis diamond films have been deposited on the molybdenum substrates using an microwave plasma enhanced chemical vapor deposition method. The effects of deposition time, surface morphology, infrared transmittance and Raman scattering have been studied. Diamond deposited on molybdenum substrate for 100 hours by MW plasma CVD from $CH_4-H_2-O_2$ gas mixture had good crystallity with $100[{\mu}m]$ thickness needed for radiation detector. Diamond radiation detector of M-I-M type was made and the current of radiation detector was increased by increasing X-ray dose.

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Anti-Inflammatory Principles from the Fruits of Evodia rutaecarpa and Their Cellular Action Mechanisms

  • Choi Yong-Hwan;Shin Eun-Myoung;Kim Yeong-Shik;Cai Xing-Fu;Lee Jung-Joon;Kim Hyun-Pyo
    • Archives of Pharmacal Research
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    • v.29 no.4
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    • pp.293-297
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    • 2006
  • The fruits of Evodia rutaecarpa Benth (Rutaceae) has long been used for inflammatory disorders and some anti-inflammatory actions of its constituents such as dehydroevodiamine, evodiamine and rutaecarpine were previously reported. Since the pharmacological data is not sufficient to clearly establish the scientific rationale of anti-inflammatory medicinal use of this plant material and the search for its active principles is limited so far, three major constituents (evodiamine, rutaecarpine, goshuyuamide II) were evaluated for their anti-inflammatory cellular action mechanisms in the present study. From the results, evodiamine and rutaecarpine were found to strongly inhibit prostaglandin $E_2$ synthesis from lipopolysaccharide-treated RAW 264.7 cells at $1-10{\mu}M$. Evodiamine inhibited cyclooxygenase-2 induction and NF-kB activation, while rutaecarpine did not. On the other hand, goshuyuamide II inhibited 5-lipoxygenase from RBL-1 cells $(IC_{50}=6.6{\mu}M)$, resulting in the reduced synthesis of leukotrienes. However, these three compounds were not inhibitory against inducible nitric oxide synthase-mediated nitric oxide production from RAW cells up to $50{\mu}M$. These pharmacological properties may provide the additional scientific rationale for anti-inflammatory use of the fruits of E. rutaecarpa.

The synthesis and formation mechanism of the fine $BaTiO_3$ powders by ultrasonic spray pyrolysis (초음파 분무 열분해법에 의한 $BaTiO_3$ 미분말의 합성 및 형성기구 규명)

  • Heo, H.B.;Shin, K.C.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.4 no.2
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    • pp.178-189
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    • 1994
  • Fine $BaTiO_3$ powder was synthesized from the various starting solution with 0.05 M by ultrasonic spray pyrolysis method. The conditions of synthesis were fixed on flow rate was 0.5 cm/sec, low temperature furnace was $300^{\circ}C$, and high temperatures furnace was $700^{\circ}C$. The formation procedure was investigated directly by SEM with the collected particle from the each reaction step. Also, the trace of particle in reaction tube was researched theoretically. Fine $BaTiO_3$ was synthesized only in the case of nitrate aqueous solution. The synthesized $BaTiO_3$ powder was porous and spherical which was consist of primary particle at the size of 19.1 nm. The formation procedure was as follows : the particle size decreased in drying step and then increased in initial thermal decomposition step. Finally, particle size was decreased to $0.42 {mu}m$. The trace of particle in reaction tube was also theoretically simulated and discussed.

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Possible Involvement of $Ca^{2+}$ Activated $K^+$ Channels, SK Channel, in the Quercetin-Induced Vasodilatation

  • Nishida, Seiichiro;Satoh, Hiroyasu
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.5
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    • pp.361-365
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    • 2009
  • Effects of quercetin, a kind of flavonoids, on the vasodilating actions were investigated. Among the mechanisms for quercetin-induced vasodilatation in rat aorta, the involvement with the $Ca^{2+}$ activated $K^+$ ($K_{Ca}$) channel was examined. Pretreatment with NE ($5\;{\mu}M$) or KCl (60 mM) was carried out and then, the modulation by quercetin of the constriction was examined using rat aorta ring strips (3 mm) at $36.5^{\circ}C$. Quercetin (0.1 to $100\;{\mu}M$) relaxed the NE-induced vasoconstrictions in a concentrationdependent manner. NO synthesis (NOS) inhibitor, NG-monomethyl-L-arginine acetate (L-NMMA), at $100\;{\mu}M$ reduced the quercetin ($100\;{\mu}M$)-induced vasodilatation from $97.8{\pm}3.7%$ (n=10) to $78.0{\pm}11.6%$ (n=5, p<0.05). Another NOS inhibitor, L-NG-nitro arginine methyl ester (L-NAME), at $10\;{\mu}M$ also had the similar effect. In the presence of both $100\;{\mu}M$ L-NMMA and $10\;{\mu}M$ indomethacin, the quercetin-induced vasodilatation was further attenuated by $100\;{\mu}M$ tetraethylammonium (TEA, a $K_{Ca}$ channel inhibitor). Also TEA decreased the quercetin-induced vasodilatation in endothelium-denuded rat aorta. Used other $K_{Ca}$ channel inhibitors, the quercetin-induced vasodilatation was attenuated by $0.3\;{\mu}M$ apamin (a SK channel inhibitor), but not by 30 nM charybdotoxin (a BK and IK channel inhibitor). Quercetin caused a concentration-dependent vasodilatation, due to the endotheliumdependent and -independent actions. Also quercetin contributes to the vasodilatation selectively with SK channel on smooth muscle.

The Effects of Rosiglitazone on in vivo Synthesis of Bone Collagen in Mice (Rosiglitazone이 마우스의 골조직 Collagen생성에 미치는 영향)

  • 김유경
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.1
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    • pp.218-221
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    • 2004
  • This study was performed to investigate the effect of rosiglitazone, a new antidiabetic agent, on in vivo synthesis of bone collagen. The mice were divided into low-fat diet group (LF), high-fat diet group (HF), and high-fat diet with rosiglitazone (6.3 $\mu\textrm{g}$/kcal diet) group (HF-Rosi), The synthesis of bone collagen was measured by stable isotope-mass spectrometric technique using $^2$$H_2O$ as a tracer. The $^2$$H_2O$ labeling protocol consisted of an initial intraperitoneal injection of 99.9% $^2$$H_2O$, to achieve approximately 2.5% body water enrichment followed by administration of 4% $^2$$H_2O$ in drinking water for 3 weeks. Although body weight gain and daily diet intake were not significantly different between groups, HF-Rosi had slightly higher body weight gain and daily diet intake than LF and HF. In addition, HF-Rosi showed significantly higher body fat content than LF and HF. Bone collagen synthesis was reduced in HF than LF and further decreased by the treatment of rosiglitazone. These results suggest rosiglitazone affect body fat content and bone turnover in mice.

Anti-wrinkle Compounds Isolated from the Seeds of Arctium lappa L. (우방자에서 분리한 주름개선 화합물)

  • Hwang, Ju-Young;Park, Tae-Soon;Kim, Dong-Hee;Hwang, Eun-Young;Lee, Jung-Noh;Lee, Ji-Young;Lee, Ghang-Tai;Lee, Kun-Kook;Son, Jun-Ho
    • Journal of Life Science
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    • v.22 no.8
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    • pp.1092-1098
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    • 2012
  • This study was carried out to discover the skin wrinkle reducing components in the seeds of Arctium lappa. The isolation of a methylene chloride-soluble fraction of 70% ethanol extract from the seeds of Arctium lappa using a procollagen type-1 synthesis and MMP-1 activity resulted in the isolation and identification of four lignin compounds: arctiin, arctigenin, matairesinol, and diarctigenin. All structures were confirmed via NMR and MS spectroscopic data. To determine cell viability and procollagen type-1 synthesis, human dermal fibroblasts were treated with 10-100 ${\mu}M$. As a result, none of the four compounds showed cytotoxicity up to 50 ${\mu}M$. We also investigated their procollagen type-1 synthesis and MMP-1 inhibition activity and found that arctiin had the highest activity in terms of both procollagen synthesis and MMP-1 inhibition among all four compounds. Putting all the data together, we suggest that arctiin be used in cosmetics as an anti-wrinkle material.

Effect of SiC Crystal Phase on Growing ZSM-5 on the Surface of SiC (탄화규소 결정상의 종류가 탄화규소 표면에 ZSM-5가 형성되는데 미치는 영향)

  • Jung, Eunjin;Lee, Yoon Joo;Kim, Younghee;Kwon, Woo Teck;Shin, Dong-Geun;Kim, Soo Ryong
    • Korean Chemical Engineering Research
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    • v.53 no.2
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    • pp.247-252
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    • 2015
  • ZSM-5 crystals grew on the surface of ${\alpha}$-SiC and ${\beta}$-SiC particles by hydrothermal synthesis method. SiC particles which were > $50{\mu}m$ of size were used, and oxide layer were developed on the surface of the particles to induce growth of ZSM-5 from the surface. Then, synthesis time and temperature condition were considered growing ZSM-5. In this study, oxide layer was formed on ${\beta}$-SiC at $900^{\circ}C$ in air, and it was controlled to grow ZSM-5 grew from the ${\beta}$-SiC surface with $150^{\circ}C$ synthesis condition. This is due to Si-O-Si or Si-O-Al bond, which is basic framework of ZSM-5 can be easily formed, from the silicon oxide film on the surface of ${\beta}$-SiC. When the synthesis temperature was $200^{\circ}C$, the size of ZSM-5 was increased, and it covered much area of the SiC surface with better crystal shapes with longer synthesis time.

ROS Scavenging Effect and Cell Viability of Opuntia humifusa Extract on Osteoblastic MC3T3-E1 Cells (천년초 추출물이 조골세포의 증식과 ROS소거능에 미치는 영향)

  • Hwang, Hyun-Jung;Jung, Bok-Mi;Kim, Mi-Hyang
    • Journal of Life Science
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    • v.21 no.12
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    • pp.1752-1760
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    • 2011
  • In this study, the effect of the Opuntiahumifusa extracts on proliferation, alkaline phosphatase (ALP) activity, collagen synthesis and ROS level of a cell was investigated using an osteoblast. Opuntiahumifusawas separated intoOpuntiahumifusapeel (OH-P), seed (OH-Se) and stem (OH-St).These were subjected to extraction by using hot water and ethanol. The proliferation of the MC3T3-E1 osteoblastic cells that were treated with OH-Se water extract were increased by approximately 120%. Regarding the effects of OH-Se on ALP activity, the $50{\mu}g/ml$ ethanol extract group showed the highest activity. The synthesis of collagen increased significantly in response to treatment with OH-Se water extract. The ROS scavenging effects of Opuntiahumifusawere investigated for involvement of oxidativedamage, cell culture and staining. Also, when OH-Se water extract $100{\mu}g/ml$ was added, the ROS level decreased by 54%. These results indicate that Opuntiahumifusa extracts have an anabolic effect on bone through the promotion of osteoblastic differentiation, suggesting that it could be used for the treatment of common metabolic bone diseases.

Antioxidant Activities and Whitening Effects of Extracts from Hippophae rhamnoides L. (비타민 나무(Hippophae rhamnoides L.) 열매 추출물의 항산화 활성 및 미백 효과)

  • Ko, Min-Seok;Lee, Hye-Jeung;Kang, Myung-Ju
    • Journal of the East Asian Society of Dietary Life
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    • v.22 no.6
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    • pp.812-817
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    • 2012
  • This study was performed to investigate the antioxidant activities and the melanin inhibitory effects of Hippophae rhamnoides L. fruit extracts. Two in vitro methods were used; the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method to determine antioxidant activity and measurements of the inhibitory effects of tyrosinase activity to determine melanogenesis in B16/F10 melanoma cells. The radical scavenging activity of the extract was 56.0% at $700{\mu}g/mL$, similar to ascorbic acid (56.9%), in the DPPH assay. The tyrosinase inhibitory activity of the extract was 52.1% and 73.4% at 100 and $500{\mu}g/mL$, which is also similar to ascorbic acid. In B16/F10 mouse melanoma cells, the extract inhibited melanin synthesis by 56% at $500{\mu}g/mL$, a more prominent inhibition of melanin synthesis compared to extracts from arbutin. These results suggest that extracts from H. rhamnoides L. have antioxidant activity and skin-whitening effects; allowing their application in cosmetics as a natural product.

Influence of Nitric Oxide on Steroid Synthesis, Growth and Apoptosis of Buffalo (Bubalus bubalis) Granulosa Cells In vitro

  • Dubey, Pawan K.;Tripathi, Vrajesh;Singh, Ram Pratap;Sastry, K.V.H.;Sharma, G.Taru
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.9
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    • pp.1204-1210
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    • 2011
  • Objective of this study was to examine the effect of sodium nitroprusside (SNP), a nitric oxide (NO) donor on steroid synthesis, growth and apoptosis of buffalo granulosa cells (GCs) in vitro. Follicular fluid of antral follicles (3-5 mm diameter) was aspirated and GCs were cultured in 0 (control), $10^{-3}$, $10^{-5}$, $10^{-7}$, $10^{-9}\;M$ of SNP for 48 h. To evaluate whether this effect was reversible, GCs were cultured in presence of $10^{-5}\;M$ SNP+1.0 mM $N^{\omega}$-nitro-L-arginine methyl ester (L-NAME) a NO synthase (NOS) inhibitor or hemoglobin (Hb, $1.0{\mu}g$) as NO scavenger. Nitrate/nitrite concentration was evaluated by Griess method, progesterone and estradiol concentrations by RIA and apoptosis by TUNEL assay. SNP ($10^{-3}$, $10^{-5}$, $10^{-7}\;M$) significantly (p<0.05) inhibited estradiol and progesterone synthesis, growth, disorganized GCs aggregates and induced apoptosis in a dose dependent manner. However, $10^{-9}\;M$ SNP induced the progesterone synthesis and stimulated GCs to develop into a uniform monolayer. Combination of SNP $10^{-5}$ M+L-NAME strengthened the inhibitory effect while, SNP+Hb together reversed these inhibitory effects. In conclusion, SNP at greater concentrations ($10^{-3}$, $10^{-5}$ and $10^{-7}\;M$) has a cytotoxic effect and it may lead to cell death whereas, at a lower concentration ($10^{-9}\;M$) induced progesterone synthesis and growth of GCs. These findings have important implications that NOS derived NO are involved at physiological level during growth and development of buffalo GCs which regulates the steroidogenesis, growth and apoptosis.