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>

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.

Relationship between Stress Gene Polymorphisms and Litter Size by AI in Pigs

Jin, H.J.,Kim, I.C.,Wee, M.S.,Yeon, S.H.,Kim, C.D.,Lee, S.S.,Cho, C.Y.,Cho, S.R.,Son, D.S.,Park, C.K. 韓國受精卵移植學會 2007 한국동물생명공학회지 Vol.22 No.4

This study was performed to investigate the relationship between PSS-HSP70 gene polymorphism and artificial insemination (AI) reproductivity in the pigs. The RFLP polymorphism of PSS and the SSCP polymorphisms of HSP70 K1, K3 and K4 PCR product were detected different patterns. In the experiment for AI of fresh semen, spring and fall season showed higher litter size born of 10.89 head than 10.47 head of summer season. Landrace was showed higher litter size of 9.96 head than that of Duroc and Yorkshire (p<0.05). Stress relating PSS and HSP70 polymorphism of PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showd a highest litter size born of 10.97 head and litter size born alive of 10.69 head than that of the other polymorphisms(p<0.05). In the experiment for AI of frozen semen, effects of season and pig breeds were not showed for litter size born. The stress relating polymorphism of PSS-Carrier, HSP70 K1-BB, K3-BB, K4-AB showed highest litter size born of 11.29 head and litter size born alive of 10.82 head and PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showed the lowest litter size born of 8.48 head and litter size born alive of 7.33 head than that of the other polymorphisms(p<0.05). These results suggest that AI litter size born for the stress of forzen thawed semen may be affected by PSS and HSP70 polymorphism in pigs.

Control of phonon transport by the formation of the Al2O3 interlayer in Al2O3-ZnO superlattice thin films and their in-plane thermoelectric energy generator performance

Park, N. W.,Ahn, J. Y.,Park, T. H.,Lee, J. H.,Lee, W. Y.,Cho, K.,Yoon, Y. G.,Choi, C. J.,Park, J. S.,Lee, S. K. Royal Society of Chemistry 2017 Nanoscale Vol.9 No.21

<P>Recently, significant progress has been made in increasing the figure-of-merit (ZT) of various nanostructured materials, including thin-film and quantum dot superlattice structures. Studies have focused on the size reduction and control of the surface or interface of nanostructured materials since these approaches enhance the thermopower and phonon scattering in quantum and superlattice structures. Currently, bismuth-tellurium-based semiconductor materials are widely employed for thermoelectric (TE) devices such as TE energy generators and coolers, in addition to other sensors, for use at temperatures under 400 K. However, new and promising TE materials with enhanced TE performance, including doped zinc oxide (ZnO) multilayer or superlattice thin films, are also required for designing solid-state TE power generating devices with the maximum output power density and for investigating the physics of in-plane TE generators. Herein, we report the growth of Al2O3/ZnO (AO/ZnO) superlattice thin films, which were prepared by atomic layer deposition (ALD), and the evaluation of their electrical and TE properties. All the in-plane TE properties, including the Seebeck coefficient (S), electrical conductivity (sigma), and thermal conductivity (kappa), of the AO/ZnO superlattice (with a 0.82 nm-thick AO layer) and AO/ZnO films (with a 0.13 nm-thick AO layer) were evaluated in the temperature range 40-300 K, and the measured S, s, and. were -62.4 and -17.5 mu V K-1, 113 and 847 (Omega cm)(-1), and 0.96 and 1.04 W m(-1) K-1, respectively, at 300 K. Consequently, the in-plane TE ZT factor of AO/ZnO superlattice films was found to be similar to 0.014, which is approximately two times more than that of AO/ZnO films (ZT of similar to 0.007) at 300 K. Furthermore, the electrical power generation efficiency of the TE energy generator consisting of four couples of n-AO/ZnO superlattice films and p-Bi0.5Sb1.5Te3 (p-BST) thin-film legs on the substrate was demonstrated. Surprisingly, the output power of the 100 nm-thick n-AO/ZnO superlattice film/p-BST TE energy generator was determined to be similar to 1.0 nW at a temperature difference of 80 K, corresponding to a significant improvement of similar to 130% and similar to 220% compared to the 100 nm-thick AO/ZnO film/p-BST and n-BT/p-BST film generators, respectively, owing to the enhancement of the TE properties, including the power factor of the superlattice film.</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>

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.

Paired many-to-many disjoint path covers in faulty hypercubes

Jo, S.,Park, J.H.,Chwa, K.Y. North-Holland Pub. Co ; Elsevier Science Ltd 2013 Theoretical computer science Vol.513 No.-

A paired many-to-many k-disjoint path cover (k-DPC for short) of a graph is a set of k disjoint paths joining k distinct source-sink pairs that cover all the vertices of the graph. Extending the notion of DPC, we define a paired many-to-many bipartite k-DPC of a bipartite graph G to be a set of k disjoint paths joining k distinct source-sink pairs that altogether cover the same number of vertices as the maximum number of vertices covered when the source-sink pairs are given in the complete bipartite, spanning supergraph of G. We show that every m-dimensional hypercube, Q<SUB>m</SUB>, under the condition that f or less faulty elements (vertices and/or edges) are removed, has a paired many-to-many bipartite k-DPC joining any k distinct source-sink pairs for any f and k≥1 subject to f+2k≤m. This implies that Q<SUB>m</SUB> with m-2 or less faulty elements is strongly Hamiltonian-laceable.

Induction of Cell Death in Human Macrophages by a Highly Virulent Korean Isolate of <i>Mycobacterium tuberculosis</i> and the Virulent Strain H37Rv

Sohn, H.,Lee, K.-S.,Kim, S.-Y.,Shin, D.-M.,Shin, S.-J.,Jo, E.-K.,Park, J.-K.,Kim, H.-J. Blackwell Publishing Ltd 2009 Scandinavian journal of immunology Vol.69 No.1

<P>Abstract</P><P>Recent studies have suggested that virulent strains of <I>Mycobacterium tuberculosis</I> induce apoptosis in macrophages less often than do attenuated strains. K-strain, which belongs to the Beijing family, is the most frequently isolated clinical strain of <I>M. tuberculosis</I> in Korea. In this study, we investigated the differential induction of cell death in human monocytic THP-1 cells by K-strain and H37Rv, a virulent but laboratory-adapted strain of <I>M. tuberculosis</I>. Although no significant difference in growth rate was observed between the cells exposed to K-strain and those exposed to H37Rv, the levels of protective cytokines such as tumour necrosis factor (TNF)-&agr;, interleukin (IL)-6 and IL-12p40 were lower in K-strain-infected cells than in H37Rv-infected cells. Cell viability assays showed that both K-strain and H37Rv, but not heat- or streptomycin-killed bacteria, induced THP-1 cell death in a TNF-independent manner. In contrast, double staining with fluorochrome-labelled inhibitors of caspase and propidium iodide and lactate dehydrogenase release assays revealed that K-strain induced significantly higher levels of necrotic cell death, rather than apoptosis, in THP-1 cells than did H37Rv. Anti-apoptotic <I>Bcl-2</I>, <I>Mcl-1</I>, <I>Bfl-1</I> and <I>Bcl-xL</I> in the cells were significantly upregulated following infection with K-strain compared with H37Rv, whereas <I>Bax</I> was slightly upregulated in response to infection with both H37Rv and K-strain. These results suggest that the highly virulent K-strain keeps cellular apoptosis as a host defense mechanism to a minimum and induces necrosis in macrophages.</P>

사료내 전해질 공급제의 종류가 이유자돈의 성장 , 뇨성상 및 영양소 이용율에 미치는 영향

박재환(J . H . Park),한인규(I . K . Han) 한국영양사료학회 1994 韓國營養飼料學會誌 Vol.18 No.3

The Effects of Stress Related Genes on Carcass Traits and Meat Quality in Pigs

H. J. Jin,B. Y. Park,J. C. Park,I. H. Hwang,S. S. Lee,S. H. Yeon,C. D. Kim,C. Y. Cho,Y. K. Kim,K. S. Min,S. T. Feng,Z. D. Li,C. K. Park,C. I. Kim 아세아·태평양축산학회 2006 Animal Bioscience Vol.19 No.2

The current study was conducted to investigate the relationship between stress related gene and meat quality in pigs. A total number of 212 three-way cross bred (Landrace-Yorkshire횞Duroc) and 38 Duroc were sampled from the Korean pig industry to determine genotype requency of porcine stress syndrome (PSS) and heat shock protein 70 kDa (HSP70) genes and their relationship with carcass traits and longissimus meat quality. Screen of HSP70 was performed by the single strand conformation polymorphism (SSCP) technique. Based on the analysis of restriction fragment length polymorphism (RFLP) in ryanodine receptor 1 (RYR1) gene, genetic disorder of PSS was related to a mutation at 18,168th (C to T) of exon 17. There was no significant difference in ultimate meat pH and backfat thickness between HSP70 K1-AA type and -BB type in pure Duroc breed. In Landrace-Yorkshire횞Duroc (L-YxD) cross bred pig, our results indicated that HSP70 derivate type in Duroc had a limited effect on backfat thickness, but L-YxD type had a noticeable linkage with HSP70 K1-AA and K3-AB. This tendency was also observed in hot carcass weight where HSP70 K1-AA and K3-AB resulted in heavier weight with 86.3 kg compared to HSP70 K1-AB and K3-BB of 74.3 kg. Results imply that stress related HSP70 genotype has a potential association with backfat thickness and carcass weight.