• 제목/요약/키워드: activator

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Anti-Oxidative and Anti-Inflammatory Effects of Malus huphensis, Ophiorrhiza cantonensis, and Psychotria rubra Ethanol Extracts (Malus huphensis, Ophiorrhiza cantonensis, Psychotria rubra 에탄올 추출물의 항산화 및 항염증 활성)

  • Jin, Kyong-Suk;Kwon, Hyun Ju;Kim, Byung Woo
    • Microbiology and Biotechnology Letters
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    • 제42권3호
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    • pp.275-284
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    • 2014
  • This study was orchestrated with the purpose of uncovering new nutraceutical resources possessing biological activities in the plant kingdom. To fulfill our objective, we analyzed several Chinese plants and selected three possessing powerful anti-oxidative activities. The anti-oxidative and anti-inflammatory effects these three Chinese plants, Malus hupehensis, Ophiorrhiza cantonensis, and Psychotria rubra ethanol extracts were then evaluated. First of all, they possessed potent scavenging activity against 1,1-diphenyl-2-picryl hydrazyl, similar with that of ascorbic acid, used as a positive control. Moreover, they inhibited lipopolysaccharide (LPS)- and hydrogen peroxide-induced reactive oxygen species, in a dose-dependent manner, in RAW 264.7 cells. Also, they induced the expression of an anti-oxidative enzyme, heme oxygenase 1, and its upstream transcription factor, nuclear factor-E2-related factor 2. Furthermore, they suppressed LPS-induced nitric oxide (NO) formation, without cytotoxicity. The inhibition of NO formation was the result of the down regulation of inducible NO synthase (iNOS). The suppression of NO and iNOS by the three extracts might be the result of modulation by the upstream transcription factors, nuclear factor ${\kappa}B$ and activator protein-1. Taken together, these results indicate that these three Chinese plants possess potent anti-oxidative and anti-inflammatory activities. Therefore, they might be utilized as promising materials in the field of nutraceuticals.

Structural and Luminescent Properties of Gd2WO6:RE3+ (RE = Dy, Sm, Dy/Sm) Phosphors for White Light Emitting Devices (백색광 소자 응용을 위한 Gd2WO6:RE3+ (RE = Dy, Sm, Dy/Sm) 형광체의 구조 및 발광 특성)

  • Park, Giwon;Jung, Jaeyong;Cho, Shinho
    • Journal of the Korean institute of surface engineering
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    • 제53권4호
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    • pp.131-137
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    • 2020
  • A series of Dy3+, Sm3+, and Dy3+/Sm3+ doped Gd2WO6 phosphors were synthesized by the conventional solid-state reaction. The X-ray diffraction patterns revealed that all of the diffraction peaks could be attributed to the monoclinic Gd2WO6 crystal structure, irrespective of the type and the concentration of activator ions. The photoluminescence (PL) excitation spectra of Dy3+-doped Gd2WO6 phosphors contained an intense charge transfer band centered at 302 nm in the range of 240-340 nm and two weak peaks at 351 and 386 nm. Under an excitation wavelength of 302 nm, the PL emission spectra consisted of two strong blue and yellow bands centered at 482 nm and 577 nm. The PL emission spectra of the Sm3+-doped Gd2WO6 phosphors had a series of three peaks centered at 568 nm, 613 nm, and 649 nm, corresponding to the 6G5/26H5/2, 6G5/26H9/2, and 6G5/26H11/2 transitions of Sm3+, respectively. The PL emission spectra of the Dy3+- and Sm3+-codoped Gd2WO6 phosphors showed the blue and yellow emission lines originating from the 4F9/26H15/2 and 4F9/24H13/2 transitions of Dy3+ and reddish-orange and red emission bands due to the 4G5/26H7/2 and 4G5/26H9/2 transitions of Sm3+. As the concentration of Sm3+ increased from 1 to 15 mol%, the intensities of two PL spectra emitted by the Dy3+ ions gradually decreased, while those of the three emission bands due to the Sm3+ ions slowly increased, thus producing the color change from white to orange. The CIE color coordinates of Gd2WO6:5 mol% Dy3+, 1 mol% Sm3+ phosphors were (0.406, 0.407), which was located in the warm white light region.

Mechanical Properties and Reaction Products of Activated Slag System Depending on Gypsum Presence and Calcium Carbonate Addition (석고 존재 및 탄산칼슘 첨가에 따른 활성 슬래그의 역학적 성능 및 반응생성물)

  • Jeong, Yeonung;Lim, Gwi Hwan;Park, Su Hyeon;Kim, Joo Hyung;Kim, Tae-Sang
    • Journal of the Korea institute for structural maintenance and inspection
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    • 제24권4호
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    • pp.55-63
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    • 2020
  • This study investigates the mechanical properties and reaction products of activated slag pastes depending on gypsum presence and calcium carbonate addition in terms of compressive strength tests and synchrotron X-ray diffraction. The chemicals of CaO and NaOH are used as activators with different two dosages. The reaction of CaO-activated slag without gypsum just accelerated by addition of calcium carbonate at early ages, but no improvement was observed at later ages. On the other hand, the mechanical properties of CaO-activated slag pastes with gypsum were improved with calcium carbonate, enhancing the stability of ettringite. The variation of mechanical properties of NaOH-activated slag pastes was negligible depending on calcium carbonate addition in case of no gypsum. The addition of calcium carbonate into NaOH-activated slag pastes with gypsum deteriorated its mechanical properties due to the ion competition between CO32- ions and SO32- ions, decreasing crystallinity of reaction products.

Screening and Extraction Condition of Antiaging Bioactive Substances from Medicinal Plants (각종 약용 식물로부터 노화 억제 관련 생리활성 물질의 탐색 및 추출 조건)

  • Yu, Hyung-Eun;Dela Paz, Leaniza Michella M.;Bae, Young-Joo;Lee, Dae-Hyoung;Park, Jong-Sang;Kwak, Hahn-Shik;Kim, Ha-Kun;Lee, Jong-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • 제34권8호
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    • pp.1136-1142
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    • 2005
  • To develop new anti-aging foods or cosmetics by using antioxidants, SOD activator and elastase inhibitor, both potent anti-aging substances, were screened from various extracts of medicinal Plants and its optimal extraction conditions were investigated. Antioxidant activity has showed the highest in methanol extracts of Prunus persica (seed; 98.0$\%$). Methanol extracts of Morus alba (leave; 41.0$\%$) showed the highest elastase inhibitory activity while Lycium chinense (fruit; 197$\%$) showed the highest activation effect in SOD activity. The Prunus persica extract that exhibited the highest activity was extracted by treatment of Prunus persica powder with methanol at 40$^{\circ}C$ for 18 h and the SOD activity was maximum with extract from Lycium chinense extracted with deionized water at 30$^{\circ}C$ for 12 h. Elastase inhibitory activity of Morus alba was maximally extracted when it was treated with 70$\%$ methanol at 50$^{\circ}C$ for 12 h.

Background $K^+$ channel currents in WEHI-231 cells, immature B lymphocytes

  • Nam, Joo-Hyun;Woo, Ji-Eun;Kim, Tae-Jin;Uhm, Dae-Yong;Kim, Sung-Joon
    • Proceedings of the Korean Biophysical Society Conference
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    • 한국생물물리학회 2003년도 정기총회 및 학술발표회
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    • pp.39-39
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    • 2003
  • In our previous study, WEHI-231, an immature B cell line, showed intractable increase in [C $a^{2+}$]$_{c}$ after the B-cell receptor (BCR) ligation and treatment with 2-aminoethoxydiphenylborate (2-APB), which was never observed in Bal-17, a mature B cell line (Nam et al., 2003, FEBS Lett). In this study, a whole cell voltage clamp study revealed a specific expression of a novel type of $K^{+}$ current, namely voltage-independent background-type $K^{+}$ channels (IK-bg), in WEHI-231 cells. IK-bg was dramatically increase by the application of 2-APB (50 $\square$M), which induced severe hyperpolarization of WEHI-231 from -45 ㎷ to -90 ㎷, When dialyzed with $Mg^{2+}$ and ATP-free pipette solution, a spontaneous development of IK-bg and membrane hyperpolarization were observed. IK-bg was insensitive to classical $K^{+}$ channel blockers (TEA, glibenclamide, $Ba^{2+}$(1 mM)), whereas blocked by quinine and quinidine in a voltage-dependent manner ($IC_{50}$/=6~9 $\square$M at +60㎷). Phorbol myrstate, a PKC activator, decreased the amplitude of IK-bg. Extracellular acidification (pH 6.5) slightly inhibited IK-bg. Arachidonic acid, riluzole, or hyposmotic stress could not affect the IK-bg after the full development by the intracellular dialysis with Mg-ATP-free solution. In a cell-attached mode of single channel recording from WEHI231, we found two types of voltage-independent $K^{+}$ channels with unitary conductance of 300 pS and 120 pS, respectively. Both channels showed very short mean open times and their open probabilities were increase by the application of 2-APB. In Bal-17 cells, no such $K^{+}$ current was observed in 50 cells tested. In summary, WEHI-231 immature B cells express background $K^{+}$ channels. The pharmacological properties and the large unitary conductance suggest that novel types of two-pore domain $K^{+}$ channels (2-P-K channels) might be expressed in WEHI-231, which may provide an intriguing targets of signal transduction in the immature B lymphocytes.e B lymphocytes.

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Inhibition of L-type Ca2+ current by ginsenoside Rd in rat ventricular myocytes

  • Lu, Cheng;Sun, Zhijun;Wang, Line
    • Journal of Ginseng Research
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    • 제39권2호
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    • pp.169-177
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    • 2015
  • Background: Ginsenoside Rd (GSRd), one of the most abundant ingredients of Panax ginseng, protects the heart via multiple mechanisms including the inhibition of $Ca^{2+}$ influx.We intended to explore the effects of GSRd on L-type $Ca^{2+}$ current ($I_{Ca,L}$) and define the mechanism of the suppression of $I_{Ca,L}$ by GSRd. Methods: Perforated-patch recording and whole-cell voltage clamp techniques were applied in isolated rat ventricular myocytes. Results: (1) GSRd reduced $I_{Ca,L}$ peak amplitude in a concentration-dependent manner [half-maximal inhibitory concentration $(IC_{50})=32.4{\pm}7.1{\mu}mol/L$] and up-shifted the current-voltage (I-V) curve. (2) GSRd ($30{\mu}mol/L$) significantly changed the steady-state activation curve of $I_{Ca,L}$ ($V_{0.5}:-19.12{\pm}0.68$ vs. $-6.26{\pm}0.38mV$; n = 5, p < 0.05) and slowed down the recovery of $I_{Ca,L}$ from inactivation [the time content (${\zeta}$) from 91 ms to 136 ms, n = 5, p < 0.01]. (3) A more significant inhibitive effect of GSRd ($100{\mu}mol/L$) was identified in perforated-patch recording when compared with whole-cell recording [$65.7{\pm}3.2%$ (n = 10) vs. $31.4{\pm}5.2%$ (n = 5), p < 0.01]. (4) Pertussis toxin ($G_i$ protein inhibitor) completely abolished the $I_{Ca,L}$ inhibition induced by GSRd. There was a significant difference in inhibition potency between the two cyclic adenosine monophosphate elevating agents (isoprenaline and forskolin) prestimulation [$55{\pm}7.8%$ (n = 5) vs. $17.2{\pm}3.5%$ (n = 5), p < 0.01]. (5) 1H-[1,2,4]Oxadiazolo[4,3-a]-quinoxalin-1-one (a guanylate cyclase inhibitor) and N-acetyl-$\small{L}$-cysteine (a nitric oxide scavenger) partly recovered the $I_{Ca,L}$ inhibition induced by GSRd. (6) Phorbol-12-myristate-13-acetate (a protein kinase C activator) and GF109203X (a protein kinase C inhibitor) did not contribute to the inhibition of GSRd. Conclusion: These findings suggest that GSRd could inhibit $I_{Ca,L}$ through pertussis toxin-sensitive G protein ($G_i$) and a nitric oxide-cyclic guanosine monophosphate-dependent mechanism.

Immunological benefits by ginseng through reciprocal regulation of Th17 and Treg cells during cyclosporine-induced immunosuppression

  • Heo, Seong Beom;Lim, Sun Woo;Jhun, Joo Yeon;Cho, Mi La;Chung, Byung Ha;Yang, Chul Woo
    • Journal of Ginseng Research
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    • 제40권1호
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    • pp.18-27
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    • 2016
  • Background: It is not clear whether ginseng affects cyclosporine A (CsA)-induced desirable immunosuppressive action. In this study, we evaluated the immunological influence of combined treatment of ginseng with CsA. Methods: Using CD4+ T cells from mouse spleens stimulated with the T cell receptor (TCR) or allogeneic antigen-presenting cells (APCs), we examined the differentiation of naïve T cells into T helper 1 (Th1), Th2, Th17, and regulatory T cells (Tregs), and their cytokine production during treatment by Korean Red Ginseng extract (KRGE) and/or CsA. The influence of KRGE on the allogeneic T cell response was evaluated by mixed lymphocyte reaction (MLR). We also evaluated whether signal transducer and activator of transcription 3 (STAT3) and STAT5 are implicated in this regulation. Results: Under TCR stimulation, KRGE treatment did not affect the population of CD4+interferon gamma ($IFN{\gamma}$)+ and CD4+interleukin (IL)-4+ cells and their cytokine production compared with CsA alone. Under the Th17-polarizing condition, KRGE significantly reduced the number of CD4+IL-17+ cells and CD4+/phosphorylated STAT3 (p-STAT3)+ cells, but increased the number of CD4+CD25+forkhead box P3 (Foxp3)+ cells and CD4+/p-STAT5+ cells compared with CsA alone. In allogeneic APCs-stimulated CD4+ T cells, KRGE significantly decreased total allogeneic T cell proliferation. Consistent with the effects of TCR stimulation, KRGE reduced the number of CD4+IL-17+ cells and increased the number of CD4+CD25+Foxp3+ cells under the Th17-polarizing condition. Conclusion: KRGE has immunological benefits through the reciprocal regulation of Th17 and Treg cells during CsA-induced immunosuppression.

Characterization of geopolymer made of municipal solid waste incineration ash slag (도시쓰레기 소각재 슬래그로 제조된 지오폴리머의 특성)

  • Kim, Yongsung;Kang, Seunggu
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • 제24권1호
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    • pp.15-20
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    • 2014
  • In this research, the geopolymer was fabricated using municipal solid waste incineration ash (denoted as MSWIA) slag and alkali activator, NaOH and its properties were analyzed. Particularly, the effects of NaOH molarity, particle size of MSWIA, and liquid/solids ratio on the compressive strength of geopolymers were investigated. The compressive strength of geopolymers fabricated increased with finer grain size of MSWIA, and optimum value of the liquid/solids ratio was identified as 0.13. As the molarity of the NaOH increased, the compressive strength of geopolymers was increased. Even more the 20 M of NaOH, but the strength was not increased. The calcium aluminum silicate and calcium aluminum silicate hydrate zeolites were generated in the geopolymer fabricated with more than 20 M of NaOH, with some unreacted silica and unknown crystals remained. The highest compressive strength, 163 MPa, of geopolymer was appeared at conditions of curing temperature $70^{\circ}C$, and 20 M of NaOH, indicating that the high concentration of NaOH accelerates the geopolymer reaction and dense microstructure. The high-strength geopolymer fabricated in the present study is expected to contribute significantly to develop the field of cement alternative substances and to improve the recycling rate of MSWIA slag.

Characteristics of Natural Loess (Hwangtoh) Paste Subjected to Geopolymerization (Geopolymerization을 적용한 천연황토 페이스트의 특성)

  • Kim, Baek-Joong;Choi, Hee-Bok;Kang, Kyung-In;Yi, Chong-Ku
    • Journal of the Korea Concrete Institute
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    • 제23권1호
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    • pp.121-127
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    • 2011
  • In this study, possible use of indigenous natural loess (Hwangtoh) as a new binding material via geopolymerization process is examined. Hwangtoh pastes with four different mix proportions of varying alkali liquid concentrations (6 M, 8 M) and the constituents of the binder as well as the alkali liquid at a constant liquid-to-binder ratio of 0.55 were prepared. Analysis of the natural loess (Hwangtoh) paste was carried out as follows : 1) Measurement of compressive strength and weight of cubic specimens versus curing time; 2) Analysis by X-ray diffraction (XRD) and scanning electron microscope (SEM) about reaction product; 3) Porosity analysis of hardened Hwangtoh paste. The result showed that it is possible to prepare Hwangtoh paste with 29.1 MPa at the age of 7 day by using alkali solution (made as 1 : 4.5 the mass ratio of liquefied $Na_2SiO_3$ and NaOH solution and applying the curing temperature of $60^{\circ}C$). Compressive strength development with respect to the degree of moisture evaporation from the paste seems to be independent of curing temperature. Therefore, it seems that higher early strength of the paste specimens cured at higher temperature can be attributed to both higher rate of reaction and moisture evaporation.

Tricho-dento-osseous Syndrome Mutant Dlx3 Shows Lower Transactivation Potential but Has Longer Half-life than Wild-type Dlx3

  • Cha, Ji-Hun;Ryoo, Hyun-Mo;Woo, Kyung-Mi;Kim, Gwan-Shik;Baek, Jeong-Hwa
    • International Journal of Oral Biology
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    • 제32권4호
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    • pp.119-125
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    • 2007
  • Dlx3 is a homeodomain protein and is known to play a role in development and differentiation of many tissues. Deletion of four base pairs in DLX3 (NT3198) is causally related to tricho-dento-osseous (TDO) syndrome (OMIM #190320), a genetic disorder manifested by taurodontism, hair abnormalities, and increased bone density in the cranium. The molecular mechanisms that explain the phenotypic characteristics of TDO syndrome have not been clearly determined. In this study, we examined phenotypic characteristics of wild type DLX3(wtDlx3) and 4-BP DEL DLX3 (TDO mtDlx3) in C2C12 cells. To investigate how wtDlx3 and TDO mtDlx3 differentially regulate osteoblastic differentiation, reporter assays were performed by using luciferase reporters containing the promoters of alkaline phosphatase, bone sialoprotein or osteocalcin. Both wtDlx3 and TDO mtDlx3 enhanced significantly all the reporter activities but the effect of mtDlx3 was much weaker than that of wtDlx3. In spite of these differences in reporter activity, electrophoretic mobility shift assay showed that both wtDlx3 and TDO mtDlx3 formed similar amounts of DNA binding complexes with Dlx3 binding consensus sequence or with ALP promoter oligonucleotide bearing the Dlx3 binding core sequence. TDO mtDlx3 exhibits a longer half-life than wtDlx3 and it corresponds to PESTfind analysis result showing that potential PEST sequence was missed in carboxy terminal of TDO mtDlx3. In addition, co-immunoprecipitation demonstrated that TDO mtDlx3 binds to Msx2 more strongly than wtDlx3. Taken together, though TDO mtDlx3 acted as a weaker transcriptional activator than wtDlx3 in osteoblastic cells, there is possibility that during in vivo osteoblast differentiation TDO mtDlx3 may antagonize transcriptional repressor activity of Msx2 more effectively and for longer period than wtDlx3, resulting in enhancement of osteoblast differentiation.