• Title/Summary/Keyword: co-activator

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Photoluminescence Characteristics of $Y_3Al_5O_{12}:Ce^{3+},Eu^{3+}$ Phosphors by $Eu^{3+}$ ions ($Eu^{3+}$ 농도에 따른 $Y_3Al_5O_{12}:Ce^{3+},Eu^{3+}$ 형광체의 광학적 특성)

  • Kwak, Hyun-Ho;Kim, Se-Jun;Park, Yong-Seo;Choi, Hyung-Wook
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.441-442
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    • 2008
  • For this study, Yttrium aluminum garnet (YAG) particles co-doped with $Ce^{3+}$ and $Eu^{3+}$ were prepared via the combustion process using the 1:1 ratio of metal ions to reagents. The characteristics of the synthesized nano powder were investigated by means of X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and photoluminescence (PL). The various YAG peaks, with the (420) main peak, appeared at all Eu concentrationin XRD patterns. The YAG phase crystallized with results that are in good agreement with the JCPDS diffraction file 33-0040. The SEM image showed that the resulting YAG:Ce,Eu powders had uniform sizes and good homogeneity. The grain size was about 50nm. The photoluminescence spectra of the YAG:Ce,Eu nanoparticles were investigated to determine the energy level of electron transition related to luminescence processes. It was composed a broad band of $Ce^{3+}$ activator into the weak line peak of $Eu^{3+}$ in YAG host. The PL intensity of $Ce^{3+}$ has the wavelengths of 480-650 nm and The PL intensity of $Eu^{3+}$ has main peak at 590nm.

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Effects of Incineration Waste Ash and Gypsum Substitution on the Properties of Blast Furnace Slag Mortar using Recycled Aggregate (소각장 애쉬 및 석고치환이 고로슬래그 미분말 기반 순환골재 모르타르의 물성에 미치는 영향)

  • Han, Min Cheol;Han, Dong Yeop;Lu, Liang Liang
    • Journal of the Korea Institute of Building Construction
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    • v.15 no.2
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    • pp.161-167
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    • 2015
  • Nowadays, all the world face to the global warming problems due to the emission of $CO_2$. From the previous studies, recycled aggregates were used as an alkali activator in blast furnace slag to achieve zero-cement concrete, and favorable results of obtaining strength were achieved. In this study, gypsum and incineration waste ash were used as the additional alkali activation and effects of the gypsum and incineration waste ash to enhance the performance of the mortar were tested. Results showed that although the replacement ratio of 0.5% of incineration waste ash and 20% of anhydrous gypsum resulted in the low of mortar at the early age, while it improved the later strength and achieved the similar strength to that of conventional mortar (at 91 days).

Preparation and Characterization of Zn2SiO4:Mn2+ Green Phosphor with Solid State Reaction (고상법에 의한 Zn2SiO4:Mn2+녹색 형광체의 제조와 특성에 관한 연구)

  • Yoo, Hyeon-Hee;Nersisyan, Hayk;Won, Hyung-Il;Won, Chang-Whan
    • Korean Journal of Materials Research
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    • v.21 no.6
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    • pp.352-356
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    • 2011
  • [ $Zn_{2(1-x)}Mn_xSiO_4$ ]$0.07{\leq}x{\leq}0.15$) green phosphor was prepared by solid state reaction. The first heating was at $900^{\circ}C-1250^{\circ}C$ in air for 3 hours and the second heating was at $900^{\circ}C$ in $N_2/H_2$(95%/5%) for 2 hours. The size effect of $SiO_2$ in forming $Zn_2SiO_4$ was investigated. The temperature for obtaining single phase $Zn_2SiO_4$ was lowered from $1100^{\circ}C$ to $1000^{\circ}C$ by decreasing the $SiO_2$ particle size from micro size to submicro size. The effect of the activators for the Photoluminescence (PL) intensity of $Zn_2SiO_4:Mn^{2+}$ was also investigated. The PL intensity properties of the phosphors were investigated under vacuum ultraviolet excitation (147 nm). The emission spectrum peak was between 520 nm and 530 nm, which was involved in green emission area. $MnCl_2{\cdot}4H_2O$, the activator source, was more effective in providing high emission intensity than $MnCO_3$. The optimum conditions for the best optical properties of $Zn_2SiO_4:Mn^{2+}$ were at x = 0.11 and $1100^{\circ}C$. In these conditions, the phosphor particle shape was well dispersed spherical and its size was 200 nm.

Molecular adaptation of the CREB-Binding Protein for aquatic living in cetaceans

  • Jeong, Jae-Yeon;Chung, Ok Sung;Ko, Young-Joon;Lee, Kyeong Won;Cho, Yun Sung;Bhak, Jong;Yim, Hyung-Soon;Lee, Jung-Hyun
    • Journal of Marine Bioscience and Biotechnology
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    • v.6 no.2
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    • pp.102-109
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    • 2014
  • Cetaceans (whales, dolphins, and porpoises) are aquatic mammals that experienced drastic changes during the transition from terrestrial to aquatic environment. Morphological changes include streamlined body, alterations in the face, transformation of the forelimbs into flippers, disappearance of the hindlimbs and the acquisition of flukes on the tail. For a prolonged diving, cetaceans acquired hypoxia-resistance by developing various anatomical and physiological changes. However, molecular mechanisms underlying these adaptations are still limited. CREB-binding protein (CREBBP) is a transcriptional co-activator critical for embryonic development, growth control, metabolic homeostasis and responses to hypoxia. Natural selection analysis of five cetacean CREBBPs compared with those from 15 terrestrial relatives revealed strong purifying selection, supporting the importance of its role in mammals. However, prediction for amino acid changes that elicit functional difference of CREBBP identified three cetacean specific changes localized within a region required for interaction with SRCAP and in proximal regions to KIX domain of CREBBP. Mutations in CREBBP or SRCAP are known to cause craniofacial and skeletal defects in human, and KIX domain of CREBBP serves as a docking site for transcription factors including c-Myb, an essential regulator of haematopoiesis. In these respects, our study provides interesting insights into the functional adaptation of cetacean CREBBP for aquatic lifestyle.

Crystal Structure and Photoluminescence of Domestic Natural Alkaline Feldspar (국산 천연알카리 장석의 결정구조와 Photoluminescence)

  • Choi, Jin-Ho;Cheon, Chae-Il;Kim, Jeong-Seog
    • Journal of the Korean Ceramic Society
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    • v.44 no.5 s.300
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    • pp.155-159
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    • 2007
  • Blue light-emitting phosphors having the excitation spectrum range of the medium-long ultraviolet ($280nm{\sim}400nm$) have been prepared by solid state reaction method. As a starting material the natural alkaline feldspar powder produced from the domestic mine field in Buyeo, Chungnam-do. The photoluminescence characteristics and crystal structures have been analyzed for the phosphor samples. The powder mixture of the natural alkaline feldspar and the rare-earth oxide was calcined at $800{\sim}1000^{\circ}C\;for\;3{\sim}4h$ in air. The calcined samples we fully ground at room temperature and then heat-treated in the mild reducing gas atmosphere of $5%H_2-95%N_2$ mixture at $1100{\sim}1150^{\circ}C\;for\;3{\sim}4h$. The natural alkaline feldspar material consists of the monoclinic orthoclase ($KAlSi_3O_8$) and the triclinic albite ($NaAlSi_3O_8$) phases. At the $0.5wt%Eu_2O_3$ addition the PL spectrum showed the maximum intensity and with further increase of $Eu_2O_3$ the PL intensity decreased. The albite phase disappeared in the $Eu_2O_3$ doped phosphors. The effect of the co-doped activator on the PL characteristics have been also discussed.

Beneficial effects of andrographolide in a rat model of autoimmune myocarditis and its effects on PI3K/Akt pathway

  • Zhang, Qi;Hu, Li-qun;Li, Hong-qi;Wu, Jun;Bian, Na-na;Yan, Guang
    • The Korean Journal of Physiology and Pharmacology
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    • v.23 no.2
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    • pp.103-111
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    • 2019
  • The study is to investigate effects of andrographolide on experimental autoimmune myocarditis (EAM). Lewis rats were immunized on day 0 with porcine cardiac myosin to establish EAM. The EAM rats were treated with either andrographolide (25, 50, 100 mg/kg/day) or vehicle for 21 days. An antigen-specific splenocytes proliferation assay was performed by using the cells from control rats immunized with cardiac myosin. Survival rates, myocardial pathology and myocardial functional parameters (left ventricle end-diastolic pressure, ${\pm}dP/dt$ and left ventricular internal dimension) of EAM rats received andrographolide were significantly improved. Andrographolide treatment caused an decrease in the infiltration of $CD3^+$ and $CD14^+$ positive cells in myocardial tissue. Moreover, andrographolide treatment caused a reduction in the plasma levels of tumor necrosis factor-alpha, interleukin-17 (IL-17) and myosin-antibody, and an increase in the level of IL-10 in EAM rats. Oral administration of andrographolide resulted in the decreased expression of p-PI3K, p-Akt without any change of PI3K and Akt. Further results indicate andrographolide significantly inhibited myosin-induced proliferation in splenocytes, and this effect was inhibited by co-treatment of SC79 (Akt activator). Our data indicate andrographolide inhibits development of EAM, and this beneficial effect may be due to powerful anti-inflammatory activity and inhibitory effect on PI3K/Akt pathway.

Root Bark of Morus Alba Suppresses the YAP Activity through Activation of Classical Hippo Signaling Pathway (상근피의 Hippo 신호전달 경로 활성화를 통한 YAP 억제 효능)

  • Cho, You Na;Choi, Da Bin;Jeong, Han Sol
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.33 no.4
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    • pp.191-197
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    • 2019
  • This study aims to evaluate the effects of the root bark of Morus alba (RMA) on the regulation of the Hippo-YAP pathway. Hippo-YAP signaling is a critical regulator in controlling organ size and tissue homeostasis. Hippo, the serine/threonine kinase phosphorylate the LATS. Phosphorylated LATS then phosphorylates and inactivates the YAP and TAZ, which are two closely related transcriptional co-activator. Here we report RMA activates the Hippo signaling, thereby inhibits the YAP/TAZ activity. First, we examine the cytotoxic effects of RMA by MTT assay. RMA was cytotoxic at concentrations higher than $50{\mu}g/ml$ in HEK293A cells. The reporter gene assay was performed to measure the activity of TEAD, a key transcription factor that controls cell growth and proliferation. RMA significantly suppressed the luciferase activity. By phos-taq gel shift assay, and western blotting, we showed that RMA enhanced the phosphorylation of YAP in wild type cells, but not in LATS1/2 knock out cells, which means RMA activates classical Hippo pathway. RMA induced the cytoplasmic sequestration of YAP. RMA also suppressed the mRNA expression of CTGF and CYR61; the two major YAP dependent genes. Taken together, RMA is considered to be a good candidate for proliferative disease such as cancer, by facilitating cell death through activating the Hippo signaling pathway.

Multi-dimensional Factors related to the Functional state of Acute Ischemic Stroke Patients - For Patients Visiting a Hospital in Gangwon-do (급성 허혈성 뇌졸중 환자의 퇴원시 기능 상태와 관련된 다차원적 요인 분석 - 강원도 소재 일개 병원의 환자를 대상으로)

  • Song, Hyun-Ju;Park, Ju-Hyun;Dong, Jae-Yong;Lee, Kwang-Soo
    • The Korean Journal of Health Service Management
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    • v.12 no.2
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    • pp.125-134
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    • 2018
  • Objectives : The purpose of this study was to analyze factors related to the functional state of stroke patients after discharge from hospital. Methods : The data was provided from a hospital in Wonju, Gangwon-do. The subjects of the analysis were those who were admitted to the emergency room due to stroke from July to December 2016. The dependent variable was the patient's functional status as measured by the modified Rankin Scale(mRS). Independent variables were demographic factors (age, sex, and marriage status), transportation and distance factors (transportation, travel distance), inpatient factors (lengths of stay, Charlson Comorbidity Index (CCI), Tissue plasminogen activator, National Institute of Health Stroke Scale (NIHSS). Hierarchial regression analysis was applied for the analysis. Results : In the hierarchical regression analysis, Model 3, including socio-demographic factors, transportation, distance factors, and inpatient factors, was the best fitted model. It showed that functional status of stroke patients was positively associated with age, length of stay, CCI, NIHSS, and negatively associated with unmarried status. Conclusions : Results indicated that management of stroke requires care from the pre-disease stage, and a customized education program policy is needed for high-risk stroke patients who are older and have comorbid illness.

Tanshinone I, an Active Ingredient of Salvia miltiorrhiza, Inhibits Differentiation of 3T3-L1 Preadipocytes and Lipid Accumulation in Zebrafish

  • Kwon, Hyo-Shin;Jang, Byeong-Churl
    • Journal of Korean Medicine for Obesity Research
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    • v.20 no.2
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    • pp.109-121
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    • 2020
  • Objectives: Tanshinone I is a bioactive constituent in Salvia miltiorrhiza. At present, the anti-obesity effect and mechanism of tanshinone I are not fully understood. Here we investigated the effect of tanshinone I on lipid accumulation in 3T3-L1 preadipocytes and zebrafish. Methods: Lipid accumulation and triglyceride (TG) content in 3T3-L1 cells were determined by Oil Red O staining and AdipoRed assay, respectively. The expression and phosphorylation levels of adipogenic/lipogenic proteins in 3T3-L1 cells were evaluated by Western blotting. The messenger RNA (mRNA) expression levels of adipogenic/lipogenic markers and leptin in 3T3-L1 cells were measured by reverse transcription polymerase chain reaction (RT-PCR). Lipid accumulation in zebrafish was assessed by LipidGreen2 staining. Results: Tanshinone I at 5 μM largely blocked lipid accumulation and reduced TG content in differentiating 3T3-L1 cells. Furthermore, tanshinone I decreased the expression of CCAAT/enhancer-binding protein-α (C/EBP-α), peroxisome proliferator-activated receptor-γ (PPAR-γ), fatty acid synthase (FAS), acetyl CoA carboxylase (ACC), and perilipin A but also the phosphorylation of signal transducer and activator of transcription-3 (STAT-3) in differentiating 3T3-L1 cells. In addition, tanshinone I increased the phosphorylation of adenosine 3',5'-cyclic monophosphate (cAMP)-activated protein kinase (AMPK) while decreased the intracellular adenosine triphosphate (ATP) content with no change in the phosphorylation and expression of liver kinase-B1 in differentiating 3T3-L1 cells. Importantly, tanshinone I also reduced the extent of lipid deposit formation in developing zebrafish. Conclusions: These findings demonstrate that tanshinone I has strong anti-adipogenic effects on 3T3-L1 cells and reduces adiposity in zebrafish, and these anti-adipogenic effect in 3T3-L1 cells are mediated through control of C/EBP-α, PPAR-γ, STAT-3, FAS, ACC, perilipin A, and AMPK.

The Tuber Extract of Pinellia ternata (Thunb.) Brei Suppresses Cancer Cell Migration by Regulating Tumor-associated Macrophages (반하 추출물의 종양연관대식세포 조절을 통한 암세포 이동능 저해 효과)

  • Park, Shin-Hyung
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.36 no.1
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    • pp.1-6
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    • 2022
  • The tuber of Pinellia ternata (Thunb.) Brei (TPT) used in traditional Oriental medicine for the treatment of cough, sputum, vomiting, and insomnia, possesses antioxidant, antibacterial, and anti-inflammatory effects. Although recent studies have reported the anticancer effects of TPT in several cancer cells, it is still unclear whether TPT regulates tumor-associated macrophage (TAM) characterized by the immunosuppressive M2 macrophage phenotype. Our results showed that the ethanol extract of TPT (ETPT) suppressed the migration of RAW264.7 mouse macrophage cells and THP-1 human monocytes differentiated into macrophages towards the conditioned media (CM) collected from lung cancer cells, suggesting that ETPT would attenuate the recruitment of macrophages into tumors. In addition, ETPT suppressed the interleukin (IL)-4 or IL-6-induced M2 macrophage polarization in RAW264.7 cells. ETPT treatment not only downregulated the mRNA expression of M2 macrophage markers including arginase-1, mannose receptor C type 1 (MRC-1), and IL-10, but also inhibited the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and STAT6, general regulators of M2 macrophage polarization. Finally, the transwell assay results showed that the CM from M2-polarized RAW264.7 cells increased the migration of mouse lewis lung carcinoma (LLC) cells, while those from RAW264.7 cells co-treated with ETPT and IL-6 significantly reduced the migration of LLC cells. Taken together, our observations clearly demonstrate that ETPT suppressed the cancer cell migration by regulating macrophage recruitment and M2 macrophage polarization.