T_c and J_c distribution in in situ processed MgB₂ bulk superconductors with/without C doping

Kim, C.J.,Kim, Y.J.,Lim, C.Y.,Jun, B.H.,Park, S.D.,Choo, K.N. The Korea Institute of Applied Superconductivity a 2014 한국초전도저온공학회논문지 Vol.16 No.2

Temperature dependence of magnetic moment (m-T) and the magnetization (M-H) at 5 K and 20 K of the in situ processed $MgB_2$ bulk pellets with/without carbon (C) doping were examined. The superconducting critical temperature ($T_c$), the superconducting transition width (${\delta}T$) and the critical current density ($J_c$) were estimated for ten test samples taken from the $MgB_2$ bulk pellets. The reliable m-T characteristics associated with the uniform $MgB_2$ formation were obtained for both $MgB_2$ pellets. The $T_cs$ and ${\delta}Ts$ of all test samples of the undoped $MgB_2$ were the same each other as 37.5 K and 1.5 K, respectively. The $T_cs$ and ${\delta}Ts$ of the C-doped $MgB_2$ were 36.5 K and 2.5 K, respectively. Unlike the m-T characteristics, there existed the difference among the M-H curves of the test samples, which might be caused by the microstructure variation. In spite of the slight $T_c$ decrease, the C doping was effective in enhancing the $J_c$ at 5 K.

한국인 혈액상의 정상치에 관한 연구 : 제1보 백혈구상에 관하여 1. Leukocyte Picture

김순호,이희우,정차근 부산의대 1968 부산의대잡지 - 부산대학교 의과대학 Vol.8 No.1

TmSR-C, scavenger receptor class C, plays a pivotal role in antifungal and antibacterial immunity in the coleopteran insect Tenebrio molitor

Kim, S.G.,Jo, Y.H.,Seong, J.H.,Park, K.B.,Noh, M.Y.,Cho, J.H.,Ko, H.J.,Kim, C.E.,Tindwa, H.,Patnaik, B.B.,Bang, I.S.,Lee, Y.S.,Han, Y.S. Pergamon Press ; Elsevier Science Ltd 2017 Insect biochemistry and molecular biology Vol.89 No.-

Scavenger receptors (SRs) constitute a family of membrane-bound receptors that bind to multiple ligands. The SR family of proteins is involved in removing cellular debris, oxidized low-density lipoproteins, and pathogens. Specifically, class C scavenger receptors (SR-C) have also been reported to be involved in phagocytosis of gram-positive and -negative bacteria in Drosophila and viruses in shrimp. However, reports are unavailable regarding the role of SR-C in antifungal immune mechanisms in insects. In this study, a full-length Tenebrio molitor SR-C (TmSR-C) sequence was obtained by 5'- and 3'-Rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The TmSR-C full-length cDNA comprised 1671 bp with 5'- and 3'-untranslated regions of 23- and 107-bp, respectively. TmSR-C encodes a putative protein of 556 amino acid residues that is constitutively expressed in all tissues of late instar larvae and 2-day-old adults, with the highest transcript levels observed in hemocytes of larvae and adults. TmSR-C mRNA showed a 2.5-fold and 3-fold increase at 24 and 6 h after infection with Candida albicans and β-glucan, respectively. Immunoassay with TmSR-C polyclonal antibody showed induction of the putative protein in the cytosols of hemocytes at 3 h after inoculation of C. albicans. RNA interference (RNAi)-based gene silencing and phagocytosis assays were used to understand the role of TmSR-C in antifungal immunity. Silencing of TmSR-C transcripts reduced the survivability of late instar larvae at 2 days post-inoculation of C. albicans, Escherichia coli, or Staphylococcus aureus. Furthermore, in TmSR-C-silenced larvae, there was a decline in the rate of microorganism phagocytosis. Taken together, results of this study suggest that TmSR-C plays a pivotal role in phagocytosing not only fungi but also gram-negative and -positive bacteria in T. molitor.

Regulation of cancer cell death by a novel compound, C604, in a c-Myc-overexpressing cellular environment

Jo, M.J.,Paek, A.R.,Choi, J.S.,Ok, C.Y.,Jeong, K.C.,Lim, J.H.,Kim, S.H.,You, H.J. North-Holland ; Elsevier Science Ltd 2015 european journal of pharmacology Vol.769 No.-

<P>The proto-oncogene c-Myc has been implicated in a variety of cellular processes, such as proliferation, differentiation and apoptosis. Several c-Myc targets have been studied; however, selective regulation of c-Myc is not easy in cancer cells. Herein, we attempt to identify chemical compounds that induce cell death in c-Myc-overexpressing cells (STF-cMyc and STF-Control) by conducting MTS assays on approximately 4000 chemical compounds. One compound, C604, induced cell death in STF-cMyc cells but not STF-Control cells. Apoptotic proteins, including caspase-3 and poly(ADP-ribose) polymerase (PAPP), were cleaved in C604-treated STF-cMyc cells. In addition, 5W620, HCT116 and NCI-H23 cells, which exhibit higher basal levels of c-Myc, underwent apoptotic cell death in response to C604, suggesting a role for C604 as an inducer of apoptosis in cancer cells with c-Myc amplification. C604 induced cell cycle arrest at the G2/M phase in cells, which was not affected by apoptotic inhibitors. Interestingly, C604 induced accumulation of c-Myc and Cdc25A proteins. In summary, a chemical compound was identified that may induce cell death in cancer cells with c-Myc amplification specifically through an apoptotic pathway. (C) 2015 Elsevier B.V. All rights reserved.</P>

소 c-KIT Receptor 유전자의 다형성에 관한 연구

장요순,김태헌,윤두학,박응우,이혜원,이학교,정일정 한국동물자원과학회 2002 한국축산학회지 Vol.44 No.6

소의 흰 반점 관련 후보유전자로 c-KIT receptor 유전자를 선정하여, c-KIT receptor 유전자내의 변이를 탐색하고 변이가 흰반점 표현형과 연관성이 있는지를 분석하였다. 한우, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin 및 Simmental 등 8개 품종의 DNA 시료를 사용하여 c-KIT receptor 유전자의 intron 6번 영역에서 다형성을 조사하고 분석하였다. c-KIT receptor 유전자의 intron 6번 영역에서는 4개의 염기치환이 발견되어, MspⅠ, BsrBⅠ 및 NdeⅠ 제한효소를 이용하여 PCR-RFLP 분석을 실시하였다. Intron 6번을 포함하는 영역의 PCR 산물 크기는 2,440 bp 이었다. MspⅠ다형성은 PCR-RFLP 분석 결과 3개의 대립유전자가 존재하였으며, 한우품종에서는 3개의 대립유전자 모두가 발견되었고, CC 형태이 유전자형을 제외한 5개의 유전자형 (AA, AB, AC, BC 및 BB)을 확인하였다. Angus, Brown Swiss, Hereford, Holstein 및 Simmental 품종에서는 A 대립유전자만을 갖는 것으로 조사되었고, 한우는 44%만 AA 유전자형을 나타내었다. BsrBⅠ 다형성은 2개의 대립유전자로서 3개의 유전자형이 나타나는 것을 확인하였으며, Charolais 및 Hereford 품종이 다른 소 품종에 비하여 A 대립유전자의 빈도가 높게 나타났다. NdeⅠ 다형성을 분석한 결과 Brown Swiss 품종에서는 NdeⅠ에 의해 절단되는 형태인 A 대립유전자만 관찰되었으며, Holstein 품종은 92%, Simmental 품종은 72%가 절단되는 형태를 나타내어, 모색이 흰색을 띠는 소 품종에서 절단되는 형태가 많았다. 소 c-KIT receptor 유전자의 intron 6번 영역에서 확인된 4개의 염기치환은 품종에 따라 다른 빈도를 보였으나, 이들 염기치환과 흰 반점과의 연관성에 대한 증거는 발견하지 못하였다. 그러므로 소의 흰 반점과 c-KIT receptor 유전자 내의 변이와의 관련성은 다른 영역에 대한 추가적인 분석과, 이미 보고된 다른 모색관련 유전자의 다형성과의 연관성 분석 등과 같은 연구가 필요한 것으로 판단된다. We considered KIT gene as a candidate gene for the white-spotting pattern in cattle. This study was carried out to detect genetic variation of c-KIT receptor gene and to investigate association between the mutation and the white-spotting pattern in cattle. PCR-RFLP analysis within intron 6 of c-KIT receptor gene were performed with 8 cattle breeds including Hanwoo, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin and Simmental. When PCR product of approximately 2,440 bp including intron 6 of c-KIT receptor gene was sequenced, four nucleotide substitutions were found within intron 6 of the bovine c-KIT receptor gene. In PCR-RFLP analysis, three alleles (A, B and C), two alleles (A and B) and two alleles (A and B) at each locus were identified by Msp Ⅰ, BsrBⅠ and NdeⅠ, respectively. Although frequencies of allele at each locus were different among cattle breeds, we could not get any evidence related with white or white spotting phenotypes in these mutations on intron 6 of c-KIT receptor gene. However, we can not entirely exclude the possibility that c-KIT receptor gene is responsible for white spotting phenotype in cattle. Thus, further studies need to detect other mutations in c-KIT receptor gene and to test association of those mutations and coat color phenotypes in cattle.

Measurements of surgeons’ exposure to ionizing radiation dose: comparison of conventional and mini C-arm fluoroscopy

Sung, K. H.,Min, E.,Chung, C. Y.,Jo, B. C.,Park, M. S.,Lee, K. SAGE Publications 2016 The journal of hand surgery. journal of the Britis Vol.41 No.3

<P>This study was performed to measure the equivalent scattered radiation dose delivered to susceptible organs while simulating orthopaedic surgery using conventional and mini C-arm fluoroscopy. In addition, shielding effects on the thyroid, thymus, and gonad, and the direct exposure delivered to the patient's hands were also compared. A conventional and mini C-arms were installed in an operating room, and a hand and an operator phantom were used to simulate a patient's hand and a surgeon. Photoluminescence dosimeters were used to measure the equivalent dose by scattered radiation arriving at the thyroid, thymus, and gonad on a whole-body phantom in the position of the surgeon. Equivalent scattered radiation doses were measured in four groups: (1) unshielded conventional C-arm group; (2) unshielded mini C-arm group; (3) lead-shielded conventional C-arm group; and (4) lead-shielded mini C-arm group. Equivalent scattered radiation doses to the unshielded group were significantly lower in the mini C-arm group than those in the conventional C-arm group for all organs. The gonad in the lead-shielded conventional C-arm group showed the highest equivalent dose among operator-susceptible organs, and radiation dose was reduced by approximately 96% compared with that in the unshielded group. Scattered radiation was not detected in any susceptible organ in the lead-shielded mini C-arm group. The direct radiation dose to the hand phantom measured from the mini C-arm was significantly lower than that measured from the conventional C-arm. The results show that the equivalent scattered radiation dose to the surgeon's susceptible organs and the direct radiation dose to a patient's hand can be decreased significantly by using a mini C-arm rather than a conventional C-arm. However, protective lead garments, such as a thyroid shield and apron, should be applied to minimize radiation exposure to susceptible organs, even during use of mini C-arm fluoroscopy.</P>

Urea와 K₂SO₄ 처리에 의한 복숭아 '미백도'에서 수확 시 과실의 무기성분 농도 및 과피색 변화

문병우,윤익구,문영지,남기웅,이영철,Moon, B.W.,Yoon, I.K.,Moon, Y.J.,Nam, K.W.,Lee, Y.C. 국립한국농수산대학교 교육개발센터 2013 현장농업연구지 = Journal of practical agricultural resear Vol.15 No.1

This study has been conducted to investigate the effect of Urea and K₂SO₄ treatment at stone hardening stage and 20 days before harvest on soil chemical properties, mineral nutrient concentration and quality of 'Mibaekdo' fruit peach. K concentration after Urea and K₂SO₄ treatment in soil was increased significantly by Urea 162g+K₂SO₄ 188g/tree(standard amount) treatment at stone hardening stage, K₂SO₄ 1.0% tree-spray, Urea 81g+K₂SO₄ 94g/tree(half amount), Urea 162g+K₂SO₄ 188g/tree and Urea 324g+K₂SO₄ 376g/tree(double amount) soil treatment before harvest 20 days compared to control. T-N, K and Ca concentration in leaf was increased significantly by all treatment. but Na concentration in leaf was increased by Urea 0.5% and K₂SO₄ 1.0% tree-spray treatment before harvest 20 days. T-N concentration in fruit skin was increased significantly by standard amount soil treatment, which decreased by K₂SO₄ 1.0% tree-spray and half amount soil treatment. T-N, K and Ca concentration in fruit flesh(1~10mm depth flesh from peel) were increased markedly by all treatment excepted Urea 0.5% tree-spray. The leaf weight at harvest was increased markedly by Urea 0.5% tree-spray, standard amount and double amount treatment before harvest 20 days. Fruit weight was increased significantly by standard amount compared to all treatment. Red fruit skin(Hunter a value) progress was effective by K₂SO₄ tree-spray, half amount and double amount treatment before harvest 20 days. Fruit SSC was increased significantly by Urea 0.5% and K₂SO₄ tree-spray before harvest 20 days, standard amount treatment at stone hardening stage compared to control.

Effects of neutron irradiation on superconducting critical temperatures of in situ processed MgB₂ superconductors

Kim, C.J.,Park, S.D.,Jun, B.H.,Kim, B.G.,Choo, K.N.,Ri, H.C. 한국초전도저온공학회 2014 한국초전도저온공학회논문지 Vol.16 No.1

Effects of neutron irradiation on the superconducting properties of the undoped $MgB_2$ and the carbon(C)-doped $MgB_2$ bulk superconductors, prepared by an in situ reaction process using Mg and B powder, were investigated. The prepared $MgB_2$ samples were neutron-irradiated at the neutron fluence of $10^{16}-10^{18}n/cm^2$ in a Hanaro nuclear reactor of KAERI involving both fast and thermal neutron. The magnetic moment-temperature (M-T) and magnetization-magnetic field (M-H) curves before/after irradiation were obtained using magnetic property measurement system (MPMS). The superconducting critical temperature ($T_c$) and transition width were estimated from the M-T curves and critical current density ($J_c$) was estimated from the M-H curves using a Bean's critical model. The $T_cs$ of the undoped $MgB_2$ and C-doped $MgB_2$ before irradiation were 36.9-37.0 K and 36.6-36.8 K, respectively. The $T_cs$ decreased to 33.2 K and 31.6 K, respectively after irradiation at neutron fluence of $7.16{\times}10^{17}n/cm^2$, and decreased to 22.6 K and 24.0 K, respectively, at $3.13{\times}10^{18}n/cm^2$. The $J_c$ cross-over was observed at the high magnetic field of 5.2 T for the undoped $MgB_2$ irradiated at $7.16{\times}10^{17}n/cm^2$. The $T_c$ and $J_c$ variation after the neutron irradiation at various neutron fluences were explained in terms of the defect formation in the superconducting matrix by neutron irradiation.

TMEM175 Is an Organelle K⁺ Channel Regulating Lysosomal Function

Cang, C.,Aranda, K.,Seo, Y.j.,Gasnier, B.,Ren, D. Cell Press ; MIT Press 2015 Cell Vol.162 No.5

Potassium is the most abundant ion to face both plasma and organelle membranes. Extensive research over the past seven decades has characterized how K<SUP>+</SUP> permeates the plasma membrane to control fundamental processes such as secretion, neuronal communication, and heartbeat. However, how K<SUP>+</SUP> permeates organelles such as lysosomes and endosomes is unknown. Here, we directly recorded organelle K<SUP>+</SUP> conductance and discovered a major K<SUP>+</SUP>-selective channel K<SUB>EL</SUB> on endosomes and lysosomes. K<SUB>EL</SUB> is formed by TMEM175, a protein with unknown function. Unlike any of the ~80 plasma membrane K<SUP>+</SUP> channels, TMEM175 has two repeats of 6-transmembrane-spanning segments and has no GYG K<SUP>+</SUP> channel sequence signature-containing, pore-forming P loop. Lysosomes lacking TMEM175 exhibit no K<SUP>+</SUP> conductance, have a markedly depolarized ΔΨ and little sensitivity to changes in [K<SUP>+</SUP>], and have compromised luminal pH stability and abnormal fusion with autophagosomes during autophagy. Thus, TMEM175 comprises a K<SUP>+</SUP> channel that underlies the molecular mechanism of lysosomal K<SUP>+</SUP> permeability.

ApoA-I mutants V156K and R173C promote anti-inflammatory function and antioxidant activities

Cho, K. H.,Park, S. H.,Han, J. M.,Kim, H. C.,Choi, Y. K.,Choi, I. Blackwell Publishing Ltd 2006 European journal of clinical investigation Vol.36 No.12

<P>Abstract</P><P>Background </P><P>Two mutants of apolipoprotein (apo) A-I, V156K and A158E, showed markedly different structural and functional properties in lipid-free and lipid-bound states in the authors’ earlier report. The physiological activities of these mutants were compared with the wild-type (WT) and R173C mutant using <I>in vitro</I> and <I>in vivo</I> experiments.</P><P>Materials and methods </P><P>A reconstituted high-density lipoprotein (rHDL) with palmitoyloleoyl phosphatidylcholine (POPC), combined with each of the apoA-I variants, was injected into the tail-veins of hypercholesterolaemic mice (C57BL6/J), which had been fed a high cholesterol and high fat (HCHF; 0·5% cholesterol, 15% lard, 0·1% sodium cholate) diet for 23 weeks, once at 0 h and then every 24 h, at a dosage of 30 mg apoA-I kg<SUP>−1</SUP> of body-weight.</P><P>Results </P><P>The V156K-rHDL and R173C-rHDL exhibited significantly stronger anti-oxidant activity against copper-mediated low-density lipoprotein (LDL) oxidation than did A158E in an apolipoprotein state. The mice injected with WT-rHDL or A158E-rHDL showed abrupt increases in total cholesterol concentrations (47% and 38%, respectively) as compared with the levels before injection, whereas the mice injected with V156K-rHDL and R173C-rHDL did not. Injection with V156K-rHDL improved serum lipids and anti-oxidative activities compared with the injection of WT-rHDL. Injection of WT-rHDL or A158E-rHDL increased serum interleukin-6 (IL-6) to 90–110 pg mL<SUP>−1</SUP>, whereas the injection of V156K-rHDL or R173C-rHDL increased serum IL-6 to 17–25 pg mL<SUP>−1</SUP> only.</P><P>Conclusion </P><P>The V156K-rHDL and R173C-rHDL displayed potent beneficial effects, including anti-oxidant and anti-inflammatory activity from both <I>in vitro</I> and <I>in vivo</I> evaluations, whereas the WT-rHDL and A158E-rHDL did not.</P>