• Title/Summary/Keyword: TPO

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A Study on Reactivity of ZnO-CuO Sorbent for Hot Gas Desulfurization (고온 연료가스 정제를 위한 ZnO-CuO 혼성탈황제의 반응 특성연구)

  • Jung, Yong-Kgil;Park, No-Kuk;Jun, Jin Hyuk;Lee, Jong-Dae;Ryu, Si-Ok;Lee, Tae-Jin
    • Clean Technology
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    • v.9 no.4
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    • pp.189-196
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    • 2003
  • ZnO-CuO mixed sorbents for desulfurization in hot gas cleaning process Were prepared and investigation on their characteristics was performed in this study. The rate of sulfidation increased as the amount of copper oxide in the composite sorbent was raised. TPO experiments were carried out to investigate the characteristics of the regeneration of the sorbents with severa1 different ratios of Zno to CuO. Copper sulfate was formed at temperatures above $400^{\circ}C$, while it was decomposed by pyrolysis above $700^{\circ}C$. $SO_2$ slippage due to $CuSO_4$ was observed in the sorbent regenerated at temperatures above $600^{\circ}C$. However, it was not observed when regenerated above $700^{\circ}C$. It was confirmed in the ZnO-CuO mixed sorbent system that CuO suppressed the vaporization of ZnO on the one hand and Zno minimized the $SO_2$ slippage due to CuO on the other hand.

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Production of Thrombopoietin Gene Targeted Clones by Homologous Recombination at $\beta$-casein Locus of Primary Bovine Ear Skin Fibroblasts

  • Mira Chang;Oh, Keon-Bong;Lee, Kyung-Kwang;Han, Yong-Mahn
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 2003.10a
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    • pp.86-86
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    • 2003
  • Research has been in progress for more than a decade to production of useful proteins by genetic modification in cattle. However, the levels of protein production in transgenic cattle have been reported very low. To enhance protein production in transgenic animal, we tried homologous recombination to donor cells for production of transgenic clone cattle through nuclear transfer procedure. Thus, we constructed the two targeting vectors of human thrombopoietin (TPO) at bovine $\beta$-casein locus using homologous recombination with 13.6 kb and 9.6 kb homology. In two targeting vectors, positive selection was through the neomycin resistance gene and negative selection was by the diphtheria toxin (DT). Gene targeting was attempted in bovine embryonic fibroblasts (bEF) and bovine ear skin fibroblasts (bESF). To determine the most appropriate concentration of neomycin for bEF and bESF, G4l8 resistance was confirmed by culturing the cells in various concentrations of the drug and both of the cells were optimally selected at $900 \mu g/ml$ of neomycin. The transfected bEF and bESF by the targeting vectors were colonized efficiently at the ratio of DNA to transfection reagent such as $4 \mu g$:2 ${mu}ell$ and $1 \mu g$:$2 \mu l$. Comparing number of healthy clones from passage 4 to passage 8, bESF (17%) persist in culture for much longer than bEF (6%). The two gene-targeted bESF clones of 30 random-integrated clones with 9.6 kb homology length were confirmed, however, nothing was out of 72 random integration clones with 13.6 kb homology length, The DT also worked more efficiently in clones transfected with the vector of 9.6 kb homology length. Our data suggests that the choice of donor cell for long culture period should be considered to obtain targeted cell clone, and the gene-targeting frequency and the DT working efficiency are dependent on the length of target homology.

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Ex vivo Expansion of CD34+ Hematopoietic Cells from Cord Blood in Various Culture Environments (다양한 배양 조건에서 제대혈 유래 CD34+ 조혈 세포의 체외 증식)

  • Choi, Yong Woon;Oh, Duk Jae
    • Korean Chemical Engineering Research
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    • v.44 no.1
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    • pp.73-80
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    • 2006
  • This study compared cell expansion and colony forming ability in human cord blood stem cells cultured ex vivo with two kinds of cytokine combinations, two kinds of media, presence or absence of fetal bovine serum (FBS) and two or three dimensional (2D or 3D) culture environments. Purified $CD34^+$ cells were cultured in the IMDM (Iscove's Modified Dulbecco's Medium) and SFM (Serum Free Medium) containing a cytokine cocktail-I (coc-I) (EPO, GMCSF, SCF, and IL-3) or a cytokine cocktail-II (coc-II) (TPO, G-CSF, SCF, IL-6, and Flt3/Flk-2 ligand) with or without FBS. Generally, higher cellular and clonogenic expansion were observed in the coc-I cytokine condition, compared to coc-II cytokine condition. 3D (Methocult) and 2D (IMDM + coc-I + FBS) conditions gave the greatest cell ($2,258{\pm}456$ fold) and CFU (BFU-E: $652{\pm}19$, CFU-GM: $520{\pm}58$, CFU-GEMM: $339{\pm}100$ fold) expansions, respectively. In aspect of medium, IMDM was better than SFM, except for coc-II condition without FBS. In conclusion, 'IMDM + coc-I + FBS' and 'IMDM + coc-I' were the best CFU expansions on the occasion of all culture conditions. FBS and 2D conditions had affirmative effect on CFU expansion, generally. These data might provide a variety of notions about ex vivo expansion of hematopoietic stem cells.

CO2 Decomposition Characteristics of Zn-ferrite Powder Prepared by Hydrothermal and Solid State Reaction (수열합성법과 고상법을 이용해 제조된 Zn-ferrite 분말의 이산화탄소 분해 특성)

  • Nam, Sung Chan;Park, Sung Youl;Yoon, Yeo Il;Jeong, Soon Kwan
    • Applied Chemistry for Engineering
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    • v.22 no.5
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    • pp.555-561
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    • 2011
  • The objective of this study is the development of carbon recycle technology which converts $CO_2$ captured from flue gas to CO or carbon and reuse in industrial fields. Since $CO_2$ is very stable and difficult to decompose, metal oxide was used as an activation agent for the decomposition of $CO_2$ at low temperature. Metal oxides which convert $CO_2$ to CO or carbon at $500^{\circ}C$ were prepared using Zn-ferrite by the solid state reaction and hydrothermal synthesis. The behaviors of $CO_2$ decomposition were studied using temperature programmed reduction/oxidation (TPR/TPO) and thermogravimetric analyzer (TGA). Zn-ferrite containing 5 wt% ZnO showed the largest reduction and oxidation. Reduction by $H_2$ was 26.53 wt%, oxidation by $CO_2$ was 25.73 wt% and 96.98% of adsorbed $CO_2$ was decomposed to $CO_2$ and carbon with excellent oxidation-reduction behaviors.

Studies on the regulation of Hematopoietic enhancement of Brassica campestris var narinosa., Canavalia gladiata DC semen and their combinational prescription via Jak2/STAT5/GATA1 Pathway in Sca-1+ hematopoietic stem cells (Sca-1+골수조혈세포에서 JAK2/STAT5/GATA-1 신호전달 경로를 통한 다채, 도두 그리고 두 조합물에 의한 조혈증진 조절에 관한 연구)

  • Kim, Kunhoae;Kim, Seung-Hyung;Cho, In-Sik;Kim, Han-Young;Kim, Dong-Seon;Lee, Young-Cheol
    • The Korea Journal of Herbology
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    • v.28 no.4
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    • pp.7-16
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    • 2013
  • Objectives : Brassica campestris var narinosa (BCN), Canavalia gladiata DC semen (CGD) and their combinational prescription (BCN+CGD) have been use to demonstrate to regulate hematopoiesis. In the current study, we investigated whether Brassica campestris var narinosa, Canavalia gladiata DC semen and their combinational prescription is related to hemato-potentiating function using Sca-$1^+$ hematopoietic stem cells (Sca-$1^+HSCs$) as a testing system. Methods : Sca-$1^+HSCs$ isolated from femur in C57bl/6 mice with leukopenia and thrombocytopenia induced by cyclophosphamide (CTX). Then, Real-time PCR was performed to measure the mRNA expression, ELISA and haematopoiesis-related gene (EPO, TPO, IL-3, SCF, c-kit, GM-CSF), the phosphorylation of JAK2, GATA-1 and STAT-5a/b were observed by western blot, and the numbers of $CD117^+/Sca-1^+$ cell and the number of granulocyte erythrocyte monocyte macrophage colony-forming units (CFU-GEMM) and erythroid burst forming units (BFU-E), semisolid clonogenic assay was performed. Result : When Sca-$1^+HSCs$ were treated with Brassica campestris var narinosa, Canavalia gladiata DC semen and their combinational prescription with rIL-3/rSCF, the expression of haematopoiesis-related (EPO, TPO, IL-3, SCF, c-kit, and GM-CSF) were significantly increased at the levels of mRNA as well as production in Sca-$1^+HSCs$. Additionally, CGS enhanced phosphorylation of JAK2, GATA-1, and signal transducer and activator of transcription-5a/b (STAT-5a/b) in Sca-$1^+HSCs$. Furthermore, their combinational prescription (BCN+CGD) significantly enhanced the growth rate of granulocyte erythrocyte monocyte macrophage colony-forming units (CFU-GEMM) and erythroid burst forming units (BFU-E) in vitro. Conclusion : These result suggest that Brassica campestris var narinosa (BCN) and Canavalia gladiata DC have hematopoietic enhancement via hematopoietic cytokine-mediated JAK2/GATA-1/STAT-5a/b pathway, and their combinational prescription (BCN+CGD) has superior hematopoietic enhancement to those of individual extracts.

Synthesis, Characterization and Ammonia Decomposition Reaction Activity of Vanadium Oxynitride Obtained from the Reduction/Nitridation of Vanadium Oxide (바나디움 산화물의 환원 및 질화반응으로부터 얻어진 바나디움 산화질화물의 제조, 특성분석 및 암모니아 분해반응에서의 촉매 활성)

  • Yun, Kyung Hee;Shin, Chae-Ho
    • Korean Chemical Engineering Research
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    • v.60 no.4
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    • pp.620-629
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    • 2022
  • By varying various experimental conditions such as heating rate, molar hourly space velocity (MHSV), and nitridation reaction temperature, vanadium oxynitride was prepared through temperature programmed reduction/nitridation reaction (TPRN) of vanadium pentoxide and ammonia, and characterization were performed. In order to investigate the physico-chemical properties of the prepared catalyst, N2 adsorption-desorption analysis, X-ray diffraction analysis (XRD), hydrogen temperature programmed reduction (H2-TPR), temperature programmed oxidation (TPO), ammonia temperature programmed desorption (NH3-TPD), transmission electron microscopy (TEM) was performed. Transformation of V2O5 with 5 m2 g-1 low specific surface area by reduction at 340 ℃ to V2O3 showed a high specific surface area value of 115 m2 g-1 by micropore formation. As the nitridation temperature increased beyond that, the specific surface area continued to decrease due to sintering. The nitridation reaction variable that had the greatest influence on the specific surface area was the reaction temperature, and the x + y value of VNxOy of a single phase approached from 1.5 to 1.0 as the nitridation reaction temperature increased. At a high reaction temperature of 680 ℃, the cubic lattice constant a was VN. close to the value. At 680 ℃, the highest nitridation temperature among the experimental conditions, the ammonia conversion rate was 93%, and no deactivation was observed.

$CO_2$ reforming of $CH_4$ and growth of CNT on Ni catalyst (메탄의 이산화탄소 개질반응과 사용된 Ni 촉매 표면에서의 CNT 성장)

  • Kim, Hee-Yeon;Jeong, Nam-Ho;Song, Kwang-Sup
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.511-512
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    • 2008
  • For the $CO_2$ reforming of $CH_4$, Ni catalyst was supported on La-hexaaluminate or on $\gamma$-$Al_2O_3$. The catalytic activities of Ni/La-hexaaluminate catalysts were measured at $700^{\circ}C$ using gas chromatography (GC) for 72 h, and the reaction was maintained up to 72 hfor the investigation of catalyst deactivation. The surface of each catalyst after 72 h reaction was investigated using SEM and TEM, and the composition of the carbon deposits was investigated by using EA, TPO and TGA. Ni/La-hexaaluminate shows higher resistance to coke deposition than conventional Ni/$Al_2O_3$ which seems to be due to strong interaction between Ni and the support material. As a result of the reforming reaction, various types of carbon deposits were created on catalyst surface and the amounts of them were much smaller in the case of La-hexaaluminate than on $Al_2O_3$.

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Exposure Expressed in Dress (복식에 표현된 노출)

  • 정연자
    • Journal of the Korea Fashion and Costume Design Association
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    • v.1 no.1
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    • pp.91-107
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    • 1999
  • The primary purpose of this study is to inquire into the characteristic of exposure presented in fashion, identify the correct concept of exposure from an aesthetic perspective, and grasp the contemporary meaning of exposure presented in fashion. As a result of study, the following findings were obtained: First, the surrealist style of fashion exhibited representations such as the relocation of the partial details, the harmonization of the natural and the artificial, the emphasis or expansion of each part of the body, and the like. It used highlighted the genital region with ornamentations or used the technique of paradoxically exposing the part of the body always covered. And it exbibited the paradoxical relationship of exposure and concealment by exposing the concealed part of the human body. Second, the post-modern style showed the complicated phenomenon that the values of several meanings such as the historic, the folk, and the like appeared in its fashion. It shares in spatiotemporal eclecticism, pluralistic characteristics and the like found in the post-modern culture. Third, the deconstructive style gets rid of the distinction between the external space and the private space by translating underwears into outer garments. It destroys clothing by tearing or perforating clothing whereby it represents the poor image. Coupled with women‘s psychology of exposure and the new generation’s way of thinking indifferent to others‘ eyes, this fashion of deconstruction occupies the great current of fashion. Deconstructive fashion gets away with the rule of ‘having to wear clothing to suit TPO(Time, Place and Occasion), the traditional norm of wearing clothing.

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Gene Expression Analysis of Megakaryocytes Derived from Human Umbilical Cord $CD34^+$ Cells by Thrombopoietin

  • Kim, Jeong-Ah;Kim, Hyung-Lae
    • Genomics & Informatics
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    • v.3 no.1
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    • pp.8-14
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    • 2005
  • Although much is known about the molecular biology of platelets, the megakaryocytes' (MKs) molecular biology was not understood so well because of their rareness. By the cloning and characterization of thrombopoietin (TPO), which is the principal regulator of the growth and development of the MKs, researches on the MKs have been growing rapidly. To understand megakaryocytopoiesis, we investigated the gene expression profile of the MKs using oligonucleotide microarray where 10,108 unique genes were spotted. Comparing the fluorescence intensities of which ratio is $\ge$ ${\mid}2{\mid}$, 372 genes were up-regulated and 541 genes were down-regulated in MKs. For confirmatory expression, RNase protection assay (RPA) establishing abundant apoptotic gene expression was carried out. In MKs, many of the known genes, including several platelet related genes, GATA binding protein were highly expressed. Particularly, TGF beta, clusterin (complement lysis inhibitor), and thymosin beta 4 (actin-sequestering molecules) were expressed highly in MKs. As MKs specific expressed genes may regulate normal and pathologic platelet (and/or MK) functions, the transcript profiling using microarray was useful on molecular understanding of MKs,

Revisiting Use of Growth Factors in Myelodysplastic Syndromes

  • Newman, Kam;Maness-Harris, Lori;El-Hemaidi, Ihab;Akhtari, Mojtaba
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1081-1091
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    • 2012
  • Myelodysplastic syndromes (MDS) represent a heterogeneous group of clonal hematologic neoplasms characterized by morphologic dysplasia, aberrant hematopoiesis and peripheral blood refractory cytopenias. MDS is recognized to be associated with an increased risk of symptomatic anemia, infectious complications and bleeding diathesis, as well as a risk of progression to acute myeloid leukemia, particularly in patients with a high IPSS score. The advent of use of hematopoietic growth factors such as granulocyte colony-stimulating factor (G-CSF) and recombinant erythropoietin (EPO) has improved symptoms in MDS patients in addition to some data that suggest there might be an improvement in survival. G-CSF is an effective therapeutic option in MDS patients, and it should be considered for the management of refractory symptomatic cytopenias. G-CSF and EPO in combination can improve outcomes in appropriate MDS patients such as those with lower-risk MDS and refractory anemia with ring sideroblasts (RARS). This article reviews use of growth factors for lower-risk MDS patients, and examines the data for G-CSF, EPO and thrombopietic growth factors (TPO) that are available or being developed as therapeutic modalities for this challenging disease.