Proposed mechanism in the change of cellular composition in the outer medullary collecting duct during potassium homeostasis.

Park, E-Y,Kim, W-Y,Kim, Y-M,Lee, J-H,Han, K-H,Weiner, I D,Kim, J Gutenberg 2012 HISTOLOGY AND HISTOPATHOLOGY Vol.27 No.12

<P>Potassium depletion (K?-D) induces hypertrophy and hyperplasia of collecting duct cells, and potassium repletion (K?-R) induces regression of these changes. The purpose of this study was to examine the time courses of the changes in cellular composition, the origin of intercalated cells (ICs) and the mechanism responsible for these changes. SD rats received K?-depleted diets for 1, 7, or 14 days. After K?-D for 14 days some of the rats received normal diets for 1, 3, 5, or 7 days. In the inner stripe of the outer medulla, K?-D increased significantly the number and proportion of H?-ATPase-positive ICs, but decreased the proportion of H?-ATPase-negative principal cells (PCs). However, proliferation was limited to H?-ATPase-negative PCs. During K?-R, the cellular composition was recovered to control level. Apoptosis increased during K?-R and exclusively limited in H?-ATPase-negative PCs. Double immunolabeling with antibodies to PC and IC markers identified both cells negative or positive for all markers during both K?-D and K?-R. Electron microscopic observation showed that ultrastructure of AE1-positive some cells were similar to AE1-negative some cells during K?-R. LC3 protein expression increased significantly and autophagic vacuoles appeared particularly in PCs on days 14 of K?-D and in ICs on days 3 of K?-R. These results suggest that PCs and ICs may interconvert in response to changes in dietary K+ availability and that autophagic pathways may be involved in the interconversion.</P>

Novel effects of FTY720 on perinuclear reorganization of keratin network induced by sphingosylphosphorylcholine: Involvement of protein phosphatase 2A and G-protein-coupled receptor-12

Park, M.K.,Park, S.,Kim, H.J.,Kim, E.J.,Kim, S.Y.,Kang, G.J.,Byun, H.J.,Kim, S.H.,Lee, H.,Lee, C.H. North-Holland ; Elsevier Science Ltd 2016 european journal of pharmacology Vol.775 No.-

<P>Sphingosylphosphorylcholine (SPC) evokes perinuclear reorganization of keratin 8 (K8) filaments and regulates the viscoelasticity of metastatic cancer cells leading to enhanced migration. Few studies have addressed the compounds modulating the viscoelasticity of metastatic cancer cells. We studied the effects of sphingosine (SPH), sphingosine 1-phosphate (S1P), FTY720 and FTY720-phosphate (FTY720P) on SPC-induced K8 phosphorylation and reorganization using Western blot and confocal microscopy, and also evaluated the elasticity of PANC-1 cells by atomic force microscopy. FTY720, FTY720P, SPH, and SIP concentration-dependently inhibited SPC-evoked phosphorylation and reorganization of K8, and migration of PANC-1 cells. SPC triggered reduction and narrow distribution of elastic constant K and conversely, FTY720 blocked them. A common upstream regulator of JNK and ERK, protein phosphatase 2A (PP2A) expression was reduced by SPC, but was restored by FTY720 and FTY72P. Butyryl forskolin, a PP2A activator, suppressed SPC-induced K8 phosphorylation and okadaic acid, a PP2A inhibitor, induced K8 phosphorylation. Gene silencing of PP2A also led to K8 phosphorylation, reorganization and migration. We also investigated the involvement of GPR12, a high-affinity SPC receptor, in SPC-evoked keratin phosphorylation and reorganization. GPR12 siRNA suppressed the SPC-triggered phosphorylation and reorganization of K8. GPR12 overexpression stimulated keratin phosphorylation and reorganization even without SPC. FTY720 and FTY720P suppressed the GPR12-induced phosphorylation and reorganization of K8. The collective data indicates that FTY720 and FTY720P suppress SPC-induced phosphorylation and reorganization of K8 in PANC-1 cells by restoring the expression of PP2A via GPR12. These findings might be helpful in the development of compounds that modulate the viscoelasticity of metastatic cancer cells and various SPC actions. (C) 2016 Elsevier B.V. All rights reserved.</P>

Overview of KSTAR research progress and future plans toward ITER and K-DEMO

Park, H.K.,Choi, M.J.,Hong, S.H.,In, Y.,Jeon, Y.M.,Ko, J.S.,Ko, W.H.,Kwak, J.G.,Kwon, J.M.,Lee, J.,Lee, J.H.,Lee, W.,Nam, Y.B.,Oh, Y.K.,Park, B.H.,Park, J.K.,Park, Y.S.,Wang, S.J.,Yoo, M.,Yoon, S.W.,B IOP 2019 Nuclear fusion Vol.59 No.11

<P>A decade-long operation of the Korean Superconducting Tokamak Advanced Research (KSTAR) has contributed significantly to the operation of superconducting tokamak devices and the advancement of tokamak physics which will be beneficial for the ITER and K-DEMO programs. Even with limited heating capability, various conventional as well as new operating regimes have been explored and have achieved improved performance. As examples, a long pulse high-confinement mode operation with and without an edge-localized mode (ELM) crash was well over 70 and 30 s, respectively. The unique capabilities of KSTAR allowed it to improve the capability of controlling harmful instabilities, and they have been instrumental in uncovering much new physics. The highlights are that the L/H transition threshold power is sensitive to the resonant magnetic perturbation (RMP) and insensitive to non-resonant magnetic perturbation. Co-<I>I</I> <SUB>p</SUB> offset rotation dominated by an electron channel predicted by general neoclassical toroidal viscosity theory was confirmed. Improved heat dispersal in a divertor system using three rows of rotating RMP was demonstrated and predictive control of the ELM-crash with <I>a priori</I> modeling was successfully tested. In magnetohydrodynamic physics, validation of the full reconnection model (i.e. <I>q</I> <SUB>0</SUB>  >  1 right after the sawtooth crash) and self-consistent validation of the anisotropic distribution of turbulence amplitude and flow in the presence of the 2/1 island with theoretical models were achieved. The turbulence amplitude induced by RMP was linearly increased with the slow RMP coil current ramp-up time (i.e. the magnetic diffusion time scale). The <I>D</I> <SUB> <I>α</I> </SUB> spikes (i.e. ELM-crash amplitude) was linearly decreased with the turbulence amplitude and not correlated with the perpendicular electron flow. In the turbulence area, a non-diffusive ‘avalanche’ transport event and the role of a quiescent coherent mode in confinement were studied. To accommodate the anticipation of a higher performance of the KSTAR plasmas with the increased heating powers, a new divertor/internal interface with a full active cooling system will be implemented after a full test of the new heating (neutral beam injection II and electron cyclotron heating) and current drive (CD) (Helicon and lower hybrid CD) systems. An upgrade plan for the internal hardware, heating systems and efficient CD system may allow for a long pulse operation of higher performance plasmas at <I>β</I> <SUB>N</SUB>  >  3.0 with <I>f</I> <SUB>bs</SUB> ~ 0.5 and <I>T</I> <SUB>i</SUB>  >  10 keV.</P>

Diagnostic usefulness of a T cell-based assay for latent tuberculosis infection in kidney transplant candidates before transplantation

Kim, S.-H.,Lee, S.-O.,Park, I.-A.,Park, S.J.,Choi, S.-H.,Kim, Y.S.,Woo, J.H.,Park, S.-K.,Park, J.S.,Kim, S.C.,Han, D.J. Blackwell Publishing Inc 2010 Transplant infectious disease Vol.12 No.2

<P>S.-H. Kim, S.-O. Lee, I.-A. Park, S.J. Park, S.-H. Choi, Y.S. Kim, J.H. Woo, S.-K. Park, J.S. Park, S.C. Kim, D.J. Han. Diagnostic usefulness of a T cell-based assay for latent tuberculosis infection in kidney transplant candidates before transplantation.Transpl Infect Dis 2010: <B>12:</B> 113–119. All rights reserved</P><P>Background</P><P>The presence of latent tuberculosis (TB) infection (LTBI) should be evaluated before kidney transplantation. Although a new T cell-based assay for diagnosing LTBI gave promising results, this assay has not yet been compared with the tuberculin skin test (TST) for diagnosing LTBI in renal transplant candidates before transplantation.</P><P>Patients and methods</P><P>All adult patients admitted to a single institute for renal transplantation over a 1-year period were prospectively enrolled. A clinically predictive risk of LTBI was defined as: (i) recent close contact with a person with pulmonary TB; (ii) abnormal chest radiography; (iii) a history of untreated or inadequately treated TB; or (iv) a new infection (i.e., a recent conversion of TST).</P><P>Results</P><P>Of 209 renal recipients, 47 (22%) had a positive TST≥5 mm, 21 (10%) had a positive TST≥10 mm, 65 (30%) had a positive T-SPOT.<I>TB</I> test, and 25 (12%) had an indeterminate T-SPOT.<I>TB</I> test. The induration size of TST was significantly associated with a high positivity rate on T-SPOT.<I>TB</I> (<I>P</I><0.001). Agreement between T-SPOT.<I>TB</I> test and TST≥10 mm was fair (<I>k</I>=0.24, 95% confidence interval 0.11–0.36). However, neither univariate nor multivariate analysis showed any association between the clinical risk for LTBI and positivity on T-SPOT.<I>TB</I> or TST.</P><P>Conclusion</P><P>T-SPOT.<I>TB</I> test was more frequently positive than TST in renal transplant candidates. However, further longitudinal studies are awaited to determine whether the ability of T-SPOT.<I>TB</I> assay to detect LTBI in renal transplant recipients can better predict the development of TB than can TST after transplantation.</P>

공정육묘 온실의 표준모델 및 자동화 시스템 개발과 활용기술연구 7 : 제4장 공정묘 생산기술 개발:제3절~제4절 Chaper4 Development of Plug Seedling Production Technology

박중춘,민영봉,정병룡,설인준,이영만,윤용철,강호종,김태규,김광용,장사문,정한택,오태한,김평태,김진일,손영걸,박봉식,김시론,이형정,오상석,김명승,조정호,하종규,임동희,이은주,변정희,이정한,최우진,강환규 경상대학교 시설원예연구소 1997 施設園藝硏究 Vol.4 No.-

국내 분리 일본뇌염 바이러스 유전자에 대한 항체생성 연구(Ⅰ) : cloning of JEV viral genes

박찬,최우영,이호동,채수림,신은진,김인범,표재환,박근용,조해월 국립보건연구원 1999 국립보건원보 Vol.36 No.-

Novel signaling axis for ROS generation during K-Ras-induced cellular transformation

Park, M-T,Kim, M-J,Suh, Y,Kim, R-K,Kim, H,Lim, E-J,Yoo, K-C,Lee, G-H,Kim, Y-H,Hwang, S-G,Yi, J-M,Lee, S-J Macmillan Publishers Limited 2014 CELL DEATH AND DIFFERENTIATION Vol.21 No.8

Reactive oxygen species (ROS) are well known to be involved in oncogene-mediated cellular transformation. However, the regulatory mechanisms underlying ROS generation in oncogene-transformed cells are unclear. In the present study, we found that oncogenic K-Ras induces ROS generation through activation of NADPH oxidase 1 (NOX1), which is a critical regulator for the K-Ras-induced cellular transformation. NOX1 was activated by K-Ras-dependent translocation of p47<SUP>phox</SUP>, a subunit of NOX1 to plasma membrane. Of note, PKCδ, when it was activated by PDPK1, directly bound to the SH3-N domain of p47<SUP>phox</SUP> and catalyzed the phosphorylation on Ser348 and Ser473 residues of p47<SUP>phox</SUP> C-terminal in a K-Ras-dependent manner, finally leading to its membrane translocation. Notably, oncogenic K-Ras activated all MAPKs (JNK, ERK and p38); however, only p38 was involved in p47<SUP>phox</SUP>-NOX1-dependent ROS generation and consequent transformation. Importantly, K-Ras-induced activation of p38 led to an activation of PDPK1, which then signals through PKCδ, p47<SUP>phox</SUP> and NOX1. In agreement with the mechanism, inhibition of p38, PDPK1, PKCδ, p47<SUP>phox</SUP> or NOX1 effectively blocked K-Ras-induced ROS generation, anchorage-independent colony formation and tumor formation. Taken together, our findings demonstrated that oncogenic K-Ras activates the signaling cascade p38/PDPK1/PKCδ/p47<SUP>phox</SUP>/NOX1 for ROS generation and consequent malignant cellular transformation.

Wrinkle structures formed by formulating UV-crosslinkable liquid prepolymers

Park, S.K.,Kwark, Y.J.,Nam, S.,Park, S.,Park, B.,Yun, S.,Moon, J.,Lee, J.I.,Yu, B.,Kyung, K.U. IPC Science and Technology Press 2016 Polymer Vol.99 No.-

Artificial wrinkles have recently been in the spotlight due to their potential use in high-tech applications. A spontaneously wrinkled film can be fabricated from UV-crosslinkable liquid prepolymers. Here, we controlled the wrinkle formation by simply formulating two UV-crosslinkable liquid prepolymers, tetraethylene glycol bis(4-ethenyl-2,3,5,6-tetrafluorophenyl) ether (TEGDSt) and tetraethylene glycol diacrylate (TEGDA). The wrinkles were formed from the TEGDSt/TEGDA formulated prepolymer layers containing up to 30 wt% of TEGDA. The wrinkle formation depended upon the rate of photo-crosslinking reaction of the formulated prepolymers. The first order apparent rate constant, k<SUB>app</SUB>, was between ca. 5.7 x 10<SUP>-3</SUP> and 12.2 x 10<SUP>-3</SUP> s<SUP>-1</SUP> for the wrinkle formation. The wrinkle structures were modulated within the k<SUB>app</SUB> mainly due to variation in the extent of shrinkage of the formulated prepolymer layers with the content of TEGDA.

Enrichment of Vitamins $D_3$, K and Iron in Eggs of Laying Hens

Park, S.W.,Namkung, H.,Ahn, H.J.,Paik, I.K. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.2

An experiment was conducted to produce eggs enriched with vitamins $D_3$, K and iron in eggs. Six hundred 97-wk-old ISA Brown force molted hens were allocated to completely randomized block arrangement of six dietary treatments: T1; control (C), T2; C+4,000 IU vitamin $D_3$+2.5 mg vitamin K+100 ppm Fe, T3; C+8,000 IU vitamin $D_3$+5.0 mg vitamin K+100 ppm Fe, T4; C+12,000 IU vitamin $D_3$+7.5 mg vitamin K+100 ppm Fe, T5; C+16,000 IU vitamin $D_3$+10.0 mg vitamin K+100 ppm Fe, T6; C+20,000 IU vitamin $D_3$+12.5 mg vitamin K+100 ppm Fe. Fe was supplemented with Fe-methionine. Each treatment consisted of five replicates of ten cages with two birds per cage. Egg production and egg weight were highest in T2 and incidence of soft and broken egg was highest in T6. Haugh unit was not different among treatments although it tended to be increased as dietary vitamins $D_3$ and K increased. Eggshell strength was not different among treatment. Concentrations of vitamin $D_3$ and K in egg yolk increased and plateaued approximately 20 days after feeding supplemented diets. The level of these vitamins peaked at 12,000 IU/kg vitamin $D_3$ and 7.5 mg/kg vitamin K supplementation and then decreased at the higher than these supplementation levels. The peak concentrations of vitamin $D_3$ and vitamin K were 4.6 times and 4.8 times greater than the control, respectively. Supplementary Fe also increased Fe content in egg yolk. It is concluded that vitamin $D_3$ and K in eggs can be effectively enriched by proper supplementation time and level of these vitamins.

Efficacy test of K-16776 against two-spotted spider mite, Tetranychus urticae (Acari: Tetranichydae)

J. J. Kim,S. Y. Kim,M. S. Hong,I. Y. Choi,K. S. Kim,B. J. Jung,T. J. Kim,D. K. Lee,N. J. Park,Y. H. Choi,K. H. Jung 한국농약과학회 2007 한국농약과학회 학술발표대회 논문집 Vol.- No.-