• Title/Summary/Keyword: SOX2

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Influence of $1{\alpha}$, 25-dihydroxyvitamin $D_3$ [1, $25(OH)_2D_3$] on the expression of Sox 9 and the transient receptor potential vanilloid 5/6 ion channels in equine articular chondrocytes

  • Hdud, Ismail M.;Loughna, Paul T.
    • Journal of Animal Science and Technology
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    • v.56 no.8
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    • pp.33.1-33.8
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    • 2014
  • Background: Sox 9 is a major marker of chondrocyte differentiation. When chondrocytes are cultured in vitro they progressively de-differentiate and this is associated with a decline in Sox 9 expression. The active form of vitamin D, 1, 25 $(OH)_2D_3$ has been shown to be protective of cartilage in both humans and animals. In this study equine articular chondrocytes were grown in culture and the effects of 1, 25 $(OH)_2D_3$ upon Sox 9 expression examined. The expression of the transient receptor potential vanilloid (TRPV) ion channels 5 and 6 in equine chondrocytes in vitro, we have previously shown, is inversely correlated with de-differentiation. The expression of these channels in response to 1, 25 $(OH)_2D_3$ administration was therefore also examined. Results: The active form of vitamin D (1, 25 $(OH)_2D_3$ when administered to cultured equine chondrocytes at two different concentrations significantly increased the expression of Sox 9 at both. In contrast 1, 25 $(OH)_2D_3$ had no significant effect upon the expression of either TRPV 5 or 6 at either the protein or the mRNA level. Conclusions: The increased expression of Sox 9, in equine articular chondrocytes in vitro, in response to the active form of vitamin D suggests that this compound could be utilized to inhibit the progressive de-differentiation that is normally observed in these cells. It is also supportive of previous studies indicating that $1{\alpha}$, 25-dihydroxyvitamin $D_3$ can have a protective effect upon cartilage in animals in vivo. The previously observed correlation between the degree of differentiation and the expression levels of TRPV 5/6 had suggested that these ion channels may have a direct involvement in, or be modulated by, the differentiation process in vitro. The data in the present study do not support this.

Reaction Characteristics of SOx/NOx Removal Using CuO/γ-Al2O3 Sorbent/Catalyst (CuO/γ-Al2O3 흡수제/촉매를 이용한 SOx/NOx 제거 반응특성)

  • Yoo, Kyung Seun;Kim, Sang Done
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.4
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    • pp.671-678
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    • 2000
  • Reaction characteristics of simultaneous removal of SOx and NOx have been investigated in a thermogravimetric analyzer and tubular fixed bed reactor using the $CuO/{\gamma}-Al_2O_3$ sorbent/catalyst. Sulfur removal capacity of $CuO/{\gamma}-Al_2O_3$ sorbent/catalyst is largely enhanced above both the temperature of $450^{\circ}C$ and the loading of 6wt% due to the participation of alumina support in a sulfation reaction. The NO reduction efficiency of 8wt% $CuO/{\gamma}-Al_2O_3$ sorbent/catalyst shows the maximum value at $370^{\circ}C$ and then decreases with the increase of reaction temperature due to the oxidation of $NH_3$ gas. The presence of sulfate on the surface of sorbent/catalyst enhances the optimum reaction temperature showing the maximum deNOx efficiency. In the simultaneous removal of SOx and NOx at $250^{\circ}C$. deNOx activity of $CuO/{\gamma}-Al_2O_3$ sorbent/catalyst is rapidly decreased due to the formation of ammonium salts such as $NH_4HSO_4$. In the simultaneous removal reaction of SOx and NOx, the optimum temperature showing the maximum deNOx efficiency increases to $400^{\circ}C$ due to the presence of $SO_2$ gas.

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Simultaneous Removal Characteristics of NOx, SOx from Combustion Gases using Plasma Chemical Reaction (플라즈마 화학반응에 의한 연소가스 중 NOx. SOx 동시제거 특성)

  • 박재윤;고용술;이재동;손성도;박상현;고희석
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.406-409
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    • 1999
  • Experimental Investigations were carried out to remove NOx, SOx simultaneously from simulated flue gas[NO(0.02%)-SO$_2$(0.08%)-$CO_2$-Air-$N_2$] by using a plasma chemical reaction. Ammonia gas(14.81%) balanced by argon was diluted by all and was Introduced to mall simulated flue gas duct through NH$_3$ Injection system which is in downstream of reactor. The NH$_3$ molecular ratio(MR) was determined based on (NH3) to [NO+S0$_2$]. MR is 1, 1.5, 2.5. The NOx removal rate significantly increased with increasing NaOH bubble quantity. The SO$_2$ removal rate was not significantly effected by applied voltage, however it fairly Increased with increasing NH$_3$ molecule ratio. By-product aerosol particle was observed by XRD(X-ray diffraction) after sampling, The NOx, SOx removal rates, when H2O vapour bubbled by dry all was injected to plasma reactor, were better than those of other cases. When aqueous NaOH solution(20%) bubbled by 2.5( ι /min) of $N_2$ and 0.5 ( ι /min) NH$_3$(MR=1.5) were injected to simulated flue gas, The NOx. SOx removal rate was 95 ~ 100[%]

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Expression of Cancer-Testis Genes in Brain Tumors

  • Lee, Myoung-Hee;Son, Eun-Ik;Kim, Ealmaan;Kim, In-Soo;Yim, Man-Bin;Kim, Sang-Pyo
    • Journal of Korean Neurosurgical Society
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    • v.43 no.4
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    • pp.190-193
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    • 2008
  • Objective : Cancer-testis (CT) genes are considered promising candidates for immunotherapeutic approaches. The aim of this study was to investigate which CT genes should be targeted in immunotherapy for brain tumors. Methods : We investigated the expression of 6 CT genes (MAGE-E1, SOX-6, SCP-1, SSX-2, SSX-4, and HOMTES-85) using reverse-transcription polymerase chain reaction in 26 meningiomas and 32 other various brain tumor specimens, obtained from the patients during tumor surgery from 2000 to 2005. Results : The most frequently expressed CT genes of meningiomas were MAGE-E1, which were found in 22/26 (85%) meningioma samples, followed by SOX-6 (9/26 or 35%). Glioblastomas were most frequently expressed SOX-6 (6/7 or 86%), MAGE-E1 (5/7 or 71%), followed by SSX-2 (2/7 or 29%) and SCP-1 (1/7 or 14%). However, 4 astrocytomas, 3 anaplastic astrocytomas, and 3 oligodendroglial tumors only expressed MAGE-E1 and SOX-6. Schwannomas also expressed SOX-6 (5/6 or 83%), MAGE-E1 (4/6 or 67%), and SCP-1 (2/6 or 33%). Conclusion : The data presented here suggest that MAGE-E1 and SOX-6 genes are expressed in a high percentage of human central nervous system tumors, which implies the CT genes could be the potential targets of immunotherapy for human central nervous system tumors.

BMP-2-Enhanced Chondrogenesis Involves p38 MAPK-mediated Down-Regulation of Wnt-7a Pathway

  • Jin, Eun-Jung;Lee, Sun-Young;Choi, Young-Ae;Jung, Jae-Chang;Bang, Ok-Sun;Kang, Shin-Sung
    • Molecules and Cells
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    • v.22 no.3
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    • pp.353-359
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    • 2006
  • The bone morphogenetic protein (BMP) family has been implicated in control of cartilage development. Here, we demonstrate that BMP-2 promotes chondrogenesis by activating p38 mitogen-activated protein kinase (MAPK), which in turn downregulates $Wnt-7a/{\beta}$-catenin signaling responsible for proteasomal degradation of Sox9. Exposure of mesenchymal cells to BMP-2 resulted in upregulation of Sox9 protein and a concomitant decrease in the level of ${\beta}$-catenin protein and Wnt-7a signaling. In agreement with this, the interaction of Sox9 with ${\beta}$-catenin was inhibited in the presence of BMP-2. Inhibition of the p38 MAPK pathway using a dominant negative mutant led to sustained Wnt-7a signaling and decreased Sox9 expression, with consequent inhibition of precartilage condensation and chondrogenic differentiation. Moreover, overexpression of ${\beta}$-catenin caused degradation of Sox9 via the ubiquitin/26S proteasome pathway. Our results collectively indicate that the increase in Sox9 protein resulting from downregulation of ${\beta}$-catenin/Wnt-7a signaling is mediated by p38 MAPK during BMP-2 induced chondrogenesis in chick wing bud mesenchymal cells.

SOx Sensor Using NASICON Solid Electrolyte (NASICON 고체 전해질을 사용한 SOx 가스 감지센서)

  • Choi, Soon-Don;Lee, Kwang-Beum
    • Journal of Sensor Science and Technology
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    • v.5 no.4
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    • pp.25-34
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    • 1996
  • A SOx sensor using NASICON electrolyte was developed for monitoring of air pollution. The following galvanic cell with $Na_{2}SiO_{3}(Pt)$ reference electrode was assembled : Pt | $Na_{2}SiO_{3}$ | NASICON | $Na_{2}SO_{4}$ | Pt, $SO_{2}$, air $Na_{2}SO_{4}$ was used as an indicator electrode to protect NASICON electrolytes from chemical reaction with $SO_{2}$. The EMFs were measured after injecting $SO_{2}$ in the initial concentrations range of $5{\sim}95ppm$ at $400{\sim}550^{\circ}C$. The measured and calculated potentials were in good agreement above $500^{\circ}C$. However, the cells were unstable below $500^{\circ}C$, most likely due to incomplete attainment of chemical equilibrium. Response time was within 10 min. Based on the stability and response time of this cell, the NASICON solid electrolyte with $Na_{2}SiO_{3}(Pt)$ as the reference electrode and $Na_{2}SO_{4}$ (Pt)as the indicator electrode showed the possibility of a reliable, inexpensive commercial solid-state SOx sensor.

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Development of SAW Gas Sensor for Monitoring SOx Gas (SOx 가스감지용 SAW 가스 센서 개발)

  • Lee, Chan-Woo;Roh, Yong-Rae;Chung, Jong-Shik;Baik, Sung-Gi
    • Journal of Sensor Science and Technology
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    • v.5 no.3
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    • pp.41-48
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    • 1996
  • We developed SAW gas sensor for monitoring SOx gas with high sensitivity. It was fabricated as a microsensor for detecting SOx gas by depositing sensing material on SAW device. As a detecting layer material, CdS was selected. Deposition of CdS in the form of thin films was carried out by the ultrasonic spray pyrolysis method using ultrasonic spray nozzle. Thin films with the uniform and large surface area for sensors were deposited. The stable pyrolysis environment provided by uniform and fine droplets formed by spray nozzle made it possible to obtain thin films with excellent quality. The minimum grain size of the CdS thin films was about 50 nm when deposited at $300^{\circ}C$. SAW gas sensors showed reasonable sensitivity and reproducibility. Further studies are required to investigate the interference of other gases to SOx gas detection.

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DDX53 Regulates Cancer Stem Cell-Like Properties by Binding to SOX-2

  • Kim, Youngmi;Yeon, Minjeong;Jeoung, Dooil
    • Molecules and Cells
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    • v.40 no.5
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    • pp.322-330
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    • 2017
  • This study investigated the role of cancer/testis antigen DDX53 in regulating cancer stem cell-like properties. DDX53 shows co-expression with CD133, a marker for cancer stem cells. DDX53 directly regulates the SOX-2 expression in anti-cancer drug-resistant $Malme3M^R$ cells. DDX53 and miR-200b were found to be involved in the regulation of tumor spheroid forming potential of Malme3M and $Malme3M^R$ cells. Furthermore, the self-renewal activity and the tumorigenic potential of $Malme3M^R$-CD133 (+) cells were also regulated by DDX53. A miR-200b inhibitor induced the direct regulation of SOX-2 by DDX53 We therefore, conclude that DDX53 may serve as an immunotherapeutic target for regulating cancer stem-like properties of melanomas.

Preparation of Porous Ceramic Bead using Mine Tailings and Its Applications to Catalytic Converter (광미(鑛尾)를 활용(活用)한 다공성 세라믹 비드 제조(製造) 및 촉매(觸媒) 변환기(變換機)로의 응용(應用))

  • Seo, Junhyung;Kim, Seongmin;Han, Yosep;Kim, Yodeuk;Lee, Junhan;Park, Jaikoo
    • Resources Recycling
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    • v.22 no.4
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    • pp.38-45
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    • 2013
  • The porous ceramic beads using mine tailing were prepared and applied to catalytic converter for NOx/SOx removal. Catalytic support was used synthesized mesoporous silica (SBA-15) which coated on surface. Internal structure for porous ceramic beads was composed of three-dimensional network structure and porosity was about 80%. In addition, the specific surface area for mesoporous silica(SBA-15) coated on converter was significantly increased 55 $m^2/g$ compared with 0.8 $m^2/g$ before coating. NOx/SOx removal experiment was performed using $V_2O_5$ and $V_2O_5$/CuO converter. NOx conversion ratio for $V_2O_5$/CuO converter was approximately increased 10% compared to $V_2O_5$ converter. In addition, catalytic converter of $V_2O_5$/CuO was shown to remove 95% of NOx and 90% of SOx at reaction temperature of $350^{\circ}C$, space velocity of 10000 $h^{-1}$ and $O_2$ concentrations of 5%, respectively.

Kir4.1 is coexpressed with stemness markers in activated astrocytes in the injured brain and a Kir4.1 inhibitor BaCl2 negatively regulates neurosphere formation in culture

  • Kwon, Jae-Kyung;Choi, Dong-Joo;Yang, Haijie;Ko, Dong Wan;Jou, Ilo;Park, Sang Myun;Joe, Eun-Hye
    • The Korean Journal of Physiology and Pharmacology
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    • v.25 no.6
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    • pp.565-574
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    • 2021
  • Astrocytes are activated in response to brain damage. Here, we found that expression of Kir4.1, a major potassium channel in astrocytes, is increased in activated astrocytes in the injured brain together with upregulation of the neural stem cell markers, Sox2 and Nestin. Expression of Kir4.1 was also increased together with that of Nestin and Sox2 in neurospheres formed from dissociated P7 mouse brains. Using the Kir4.1 blocker BaCl2 to determine whether Kir4.1 is involved in acquisition of stemness, we found that inhibition of Kir4.1 activity caused a concentration-dependent increase in sphere size and Sox2 levels, but had little effect on Nestin levels. Moreover, induction of differentiation of cultured neural stem cells by withdrawing epidermal growth factor and fibroblast growth factor from the culture medium caused a sharp initial increase in Kir4.1 expression followed by a decrease, whereas Sox2 and Nestin levels continuously decreased. Inhibition of Kir4.1 had no effect on expression levels of Sox2 or Nestin, or the astrocyte and neuron markers glial fibrillary acidic protein and β-tubulin III, respectively. Taken together, these results indicate that Kir4.1 may control gain of stemness but not differentiation of stem cells.