• Title/Summary/Keyword: Activators

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A Study on the Inhibitory Effect and Mechanism of Lonicera Japonica on Type I Interferon (금은화의 type I interferon 억제효과 및 기전에 관한 연구)

  • Kang, Yong-Goo;Ryu, Ik-Han;Kim, Song-Baek;Choi, Chang-Min;Seo, Yun-Jung;Cho, Han-Baek
    • The Journal of Korean Obstetrics and Gynecology
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    • v.26 no.2
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    • pp.17-32
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    • 2013
  • Objectives: The purpose of this study was to investigate whether Lonicera japonica(LJ) could inhibit LPS-induced type I IFN production. Methods: To evaluate inhibitory effect of LJ on type I IFN, we examined type I IFN, IRF-1, 7 and IL-10 production on LPS-induced macrophages using real time RT-PCR. Next, we observed the interaction of type I IFN, IRF-1, 7 and IL-10 using IL-10 neutralizing antibody. Finally we examined the activation of STAT-1, 3 using western blot. Results: LJ inhibited Type I IFN expression of mRNA and increased IL-10 expression of mRNA. Also LJ inhibited the level of IRF-1, 7 mRNA and the nuclear translocation of IRF-3. Further more, LJ reduced the activation of STAT-1, 3 which are involved in continuous secretion of immune cytokines. Blockade of IL-10 action caused a significant reduction of type I IFN and IRF-1, 7 than LPS-induced LJ pretreatment. Conclusions: LJ inhibits LPS-induced production of type I IFN by IL-10. This study may provide a clinical basis for anti-inflammatory properties of LJ.

Diagnostic and Prognostic Value of miR-205 in Colorectal Cancer

  • Orang, Ayla Valinezhad;Safaralizadeh, Reza;Feizi, Mohammad Ali Hosseinpour;Somi, Mohammad Hossein
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.9
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    • pp.4033-4037
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    • 2014
  • Emerging evidence has shown associations of microRNA-205 (miR-205) with crucial cell processes such as the epithelial-mesenchymal transition (EMT) and aberrant expression with tumorigenesis in many types of human malignancy. This prospective study characterized the contribution of miR-205 to the colorectal cancer (CRC) tumorigenesis. The real-time reverse transcription-polymerase chain reaction was used to examine miR-205 levels prospectively in 36 pairs of samples of CRC tissue and adjacent noncancerous tissue (>2 cm from cancer tissue). In addition, the relationship between miR-205 levels and clinicopathological features was explored. The capability of miR-205 to function as a tumor marker was also examined. miR-205 expression levels did not show significant changes overall. However, miR-205 was significantly downregulated in a group of CRC samples compared with matched noncancerous tissue samples. Moreover, decreased miR-205 correlated significantly with lymphatic metastasis. A receiver operating characteristic (ROC) curve also showed an optimum cut off point of $1.4{\times}10^{-3}$ to distinguish lymphatic metastatic CRCs from non-metastatic CRCs. Interestingly we found lymphatic metastasis in almost 80% of the depressed samples. This study suggested that miR-205 could be reduced in the majority of metastatic CRCs and the risk of CRC metastasis may be predicted by monitoring miR-205 in patient samples collected at the time of the initial diagnosis. Therefore, targeting miR-205 and its potential environmental activators might be a promising therapeutic option to prevent malignant progression toward metastasis.

The Strength Properties of Alkali-Activated Slag Mortars by Combined Caustic Alkali with Sodium Carbonate as Activator (가성알칼리와 탄산나트륨을 혼합한 활성화제를 사용한 알칼리 활성화 고로슬래그 모르타르의 강도 특성)

  • Kim, Tae-Wan
    • Journal of the Korea Concrete Institute
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    • v.24 no.6
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    • pp.745-752
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    • 2012
  • This paper studies the effect of the compressive strength for combined alkali-activated slag mortars. The effect of activators such as alkali type and dosage factor on the strength was investigated. The alkalis combinations made using five caustic alkalis (sodium hydroxide (NaOH, A series), calcium hydroxide ($Ca(OH)_2$, B series), magnesium hydroxide ($Mg(OH)_2$, C series), aluminum hydroxide ($Al(OH)_3$, D series), and potassium hydroxide (KOH, E series)) with sodium carbonate ($Na_2CO_3$) were evaluated. The mixtures were combined in different dosage at 1M, 2M, and 3M. The study results showed that the compressive strength of combined alkali-activated slag mortars tended to increase with increasing sodium carbonate. The strength of combined alkali-activated slag mortars was better than that of control cases (without sodium carbonate). The result from scanning electron microscopy (SEM) analysis confirmed that there were reaction products of calcium silicate hydrate (C-S-H) and alumina-silicate gels from combined alkali-activated slag specimens.

Pycnometric and Spectroscopic Studies of Red Phosphors Ca2+(1-1.5x)WO4:Eu3+x and Ca2+(1-2x)WO4:Eu3+x,Na+x

  • Cho, Seon-Woog
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2769-2773
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    • 2013
  • Red phosphors $Ca_{(1-1.5x)}Eu_xWO_4$ and $Ca_{(1-2x)}Eu^_xNa_xWO_4$ were synthesized with various concentrations x of $Eu^{3+}$ ions by using a solid-state reaction method. The crystal structure of the red phosphors were found to be a tetragonal scheelite structure with space group $I4_1/a$. X-ray diffraction (XRD) results show the (112) main diffraction peak centered at $2{\theta}=28.71^{\circ}$, and indicate that there is no basic structural deformation caused by the vacancies ${V_{Ca}}^{{\prime}{\prime}}$ or the $Eu^{3+}$ (and $Na^+$) ions in the host crystals. Densities of $Ca_{(1-1.5x)}Eu_xWO_4$ were measured on a (helium) gas pycnometer. Comparative results between the experimental and theoretical densities reveal that $Eu^{3+}$ (and $Na^+$) ions replace the $Ca^{2+}$ ions in the host $CaWO_4$. Also, the photoluminescence (PL) emission and photoluminescence excitation (PLE) spectra show the optical properties of trivalent $Eu^{3+}$ ions, not of divalent $Eu^{2+}$. Raman spectra exhibit that, without showing any difference before and after the doping of activators to the host material $CaWO_4$, all the gerade normal modes occur at the identical frequencies with the same shapes and weaker intensities after the substitution. However, the FT-IR spectra show that some of the ungerade normal modes have shifted positions and different shapes, caused by different masses of $Eu^{3+}$ ions (or $Na^+$ ions, or ${V_{Ca}}^{{\prime}{\prime}}$ vacancies) from $Ca^{2+}$.

Intracellular calcium-dependent regulation of the sperm-specific calcium-activated potassium channel, hSlo3, by the BKCa activator LDD175

  • Wijerathne, Tharaka Darshana;Kim, Jihyun;Yang, Dongki;Lee, Kyu Pil
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.2
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    • pp.241-249
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    • 2017
  • Plasma membrane hyperpolarization associated with activation of $Ca^{2+}$-activated $K^+$ channels plays an important role in sperm capacitation during fertilization. Although Slo3 (slowpoke homologue 3), together with the auxiliary ${\gamma}^2$-subunit, LRRC52 (leucine-rich-repeat-containing 52), is known to mediate the pH-sensitive, sperm-specific $K^+$ current KSper in mice, the molecular identity of this channel in human sperm remains controversial. In this study, we tested the classical $BK_{Ca}$ activators, NS1619 and LDD175, on human Slo3, heterologously expressed in HEK293 cells together with its functional interacting ${\gamma}^2$ subunit, hLRRC52. As previously reported, Slo3 $K^+$ current was unaffected by iberiotoxin or 4-aminopyridine, but was inhibited by ~50% by 20 mM TEA. Extracellular alkalinization potentiated hSlo3 $K^+$ current, and internal alkalinization and $Ca^{2+}$ elevation induced a leftward shift its activation voltage. NS1619, which acts intracellularly to modulate hSlo1 gating, attenuated hSlo3 $K^+$ currents, whereas LDD175 increased this current and induced membrane potential hyperpolarization. LDD175-induced potentiation was not associated with a change in the half-activation voltage at different intracellular pHs (pH 7.3 and pH 8.0) in the absence of intracellular $Ca^{2+}$. In contrast, elevation of intracellular $Ca^{2+}$ dramatically enhanced the LDD175-induced leftward shift in the half-activation potential of hSlo3. Therefore, the mechanism of action does not involve pH-dependent modulation of hSlo3 gating; instead, LDD175 may modulate $Ca^{2+}$-dependent activation of hSlo3. Thus, LDD175 potentially activates native KSper and may induce membrane hyperpolarization-associated hyperactivation in human sperm.

Construction of the Detection System of Endocrine Disrupters using Yeast Two-Hybrid System with Human Estrogen Receptor ligand Binding Domain and Co-activators (Human Estrogen Receptor Ligand Binding Domain (hER LBD)과 Co-activator로 구성된 효모 Two-Hybrid System을 이용한 내분비계장애물질 검출계의 구축)

  • 이행석;조은민;류재천
    • Environmental Mutagens and Carcinogens
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    • v.22 no.3
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    • pp.175-182
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    • 2002
  • Endocrine disruptors (EDs) are the chemicals that affect endocrine systems through activation or inhibition of steroid hormone response. It is necessary to have a good system to evaluate rapidly and accurately endocrine-disrupting activities of suspected chemicals and their degradation products. The key targets of EDs are nuclear hormone receptors, which bind to steroid hormones and regulate their gene transcription. We constructed a co-expression system of Gal4p DNA binding domain (DBD)- ligand binding domain of human estrogen receptor $\alpha$ or $\beta$, and Gal4p transactivation domain (TAD)-co-activator AIB-1, SRC-1 or TIF-2 in Saccharomyces cerevisiae with a chromosome-integrated lacZ reporter gene under the control of CYC1 promoter and Gal4p binding site (GAL4 upstream activating sequence, GAL4$_{UAS}$). Expression of this reporter gene was dependent on the presence of estrogen or EDs in the culture medium. We found that the two-hybrid system with combination of the hER$\beta$ LBD and co-activator SRC-1 was most effective in the xenoestrogen-dependent induction of reporter activity. The extent of transcriptional activation by those chemicals correlated with their estrogenic activities measured by other assay systems, indicating that this assay system is efficient and reliable for measuring estrogenic activity. The data in this research demonstrated that the yeast detection system using steroid hormone receptor and co-activator is a useful tool for identifying chemicals that interact with steroid receptors.s.

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STAT6 Gene Polymorphisms in Allergic Rhinitis

  • Kim, Jeong Joong;Kim, Min Su;Lee, Jung Hun;Choi, Tae Wook;Choi, Sang Heon;Lee, Jae Hoon;Chung, Hun Taeg
    • Genomics & Informatics
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    • v.2 no.3
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    • pp.126-130
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    • 2004
  • T helper-type 2 cytokines, such as IL-4 and IL-13, may play a central role in allergic diseases. The protein known as signal transducers and activators of transcription 6 (STAT6) is a key transcription factor involved in both IL-4- and -13-mediated biological responses. Two polymorphisms of the STAT 6 gene (exon 1 and G2964A variant) have been found. We investigated whether these STAT6 gene polymorph isms were associated with allergic rhinitis. Blood samples for genetic analysis were obtained from 285 individuals with allergic rhinitis and from 271 healthy subjects without atopic disease. The G2964A variant of the STAT6 gene was genotyped using PCR-RFLP analysis. The GT repeat polymorphism in exon 1 of the STAT6 gene was genotyped by fragment analysis. There was no association between the 2964A variant and GT repeat polymorphism in exon 1 of the STAT6 and allergic rhinitis in a Korean population (both p > 0.05). Our results suggest that a combination of STAT6 gene polymorphisms is not a useful marker for predicting allergic rhinitis.

Mechanical Properties of High Strength Concrete with High Volume Mineral Admixture (다량의 혼화재를 사용한 고강도 콘크리트의 역학적 특성)

  • Baek, Chul-Woo;Park, Cho-Bum;Choi, Sung-Woo;Jo, Hyun-Tae;Ryu, Deuk-Hyun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.2 no.3
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    • pp.180-187
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    • 2014
  • The purpose of this study is to evaluate on the mechanical properties of High Volume Mineral Admixture(HVMA) high strength concrete to reduce the amount use of Ordinary Potland Cement, to discover the optimized HVMA binder and to test HVMA concrete based on the change of W/B and curing temperature. The results were shown as follows: The HVMA binder using the mixture of combined heat power plant fly ash and anhydrous gypsum known as inorganic activators with the mixture of blast furnace slag and fly ash was optimized. The mixture of HVMA high strength concrete at 26% of W/B ratio had a good result on flow characteristic and mechanical properties. High strength HVMA concrete over 50MPa is possibly manufactured over curing temperature $20^{\circ}C$.

Effect of Particle Size and Unburned Carbon Content of Fly Ash from Hadong Power Plant on Compressive Strength of Geopolymers (하동화력발전소 비산재의 입도크기와 미연탄소 함량이 지오폴리머의 압축강도에 미치는 영향)

  • Kang, Nam-Hee;Chon, Chul-Min;Jou, Hyeong-Tae;Lee, Sujeong
    • Korean Journal of Materials Research
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    • v.23 no.9
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    • pp.510-516
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    • 2013
  • Fly ash is one of the aluminosilicate sources used for the synthesis of geopolymers. The particle size distribution of fly ash and the content of unburned carbon residue are known to affect the compressive strength of geopolymers. In this study, the effects of particle size and unburned carbon content of fly ash on the compressive strength of geopolymers have been studied over a compositional range in geopolymer gels. Unburned carbon was effectively separated in the $-46{\mu}m$ fraction using an air classifier and the fixed carbon content declined from 3.04 wt% to 0.06 wt%. The mean particle size ($d_{50}$) decreased from $22.17{\mu}m$ to $10.79{\mu}m$. Size separation of fly ash by air classification resulted in reduced particle size and carbon residue content with a collateral increase in reactivity with alkali activators. Geopolymers produced from carbon-free ash, which was separated by air classification, developed up to 50 % higher compressive strength compared to geopolymers synthesized from raw ash. It was presumed that porous carbon particles hinder geopolymerization by trapping vitreous spheres in the pores of carbon particles and allowing them to remain intact in spite of alkaline attack. The microstructure of the geopolymers did not vary considerably with compressive strength, but the highest connectivity of the geopolymer gel network was achieved when the Si/Al ratio of the geopolymer gel was 5.0.

Luminescence characterization of $YVO_4$: $Eu^{3+}$, $Bi^{3+}$ red phosphor by rapid microwave heating synthesis (급속 microwave 열처리 방법으로 합성한 $YVO_4$: $Eu^{3+}$, $Bi^{3+}$ 적색 형광체의 발광 특성)

  • Park, W.J.;Song, Y.H.;Moon, J.W.;Yoon, D.H.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.18 no.4
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    • pp.169-173
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    • 2008
  • $Eu^{3+}$ and $Bi^{3+}$ co-doped $YVO_4$ phosphors were produced by a microwave heating process. When the microwave heating method was synthesized,. the particle size was very small and the particles tended to agglomerate. However, as the heating time increased, the particle size increased and the agglomeration decreased. The emission spectrum exhibited a weak band for $^5D_0{\longrightarrow}^7F_1$ at 594.91 and 602.3 nm and strong sharp peaks at 616.7 and 620.0 nm due to the $^5D_0{\longrightarrow}^7F_2$ transition of $Eu^{3+}$. Microwave heating synthesis can provide a product without long time heating as well as good homogeneous distribution of activators.