¹³¹I-labeled chitosan hydrogels for radioembolization: A preclinical study in small animals

Hwang, H.,Kim, K.I.,Kwon, J.,Kim, B.S.,Jeong, H.S.,Jang, S.J.,Oh, P.S.,Park, H.S.,Lim, S.T.,Sohn, M.H.,Jeong, H.J. Pergamon Press 2017 Nuclear medicine and biology Vol.52 No.-

<P>Advances in knowledge: Transarterial embolization is a conceivable treatment option for patients with inoperable liver cancer to mitigate the disease progression. Recently, we have developed chitosan-based hydrogel microparticles. In the present study, the hydrogel microparticles were radiolabeled with I-131 for treatment of liver cancer. Our results demonstrated that a hepatic arterial injection of I-125 -labeled Chi resulted in substantial liver accumulation, which was accompanied by virtually no extrahepatic deposition. The results of the present study also showed that administration of I-131 Chi markedly suppressed tumor growth, compared to controls and to animals receiving unlabeled Chi. I-131 -labeled chitosan hydrogel microparticles represent a new therapeutic approach for treatment of liver cancer. (C) 2017 Elsevier Inc. All rights reserved.</P>

Phentermine induces conditioned rewarding effects via activation of the PI3K/Akt signaling pathway in the nucleus accumbens

Hong, S. I.,Kim, M. J.,You, I. J.,Kwon, S. H.,Ma, S. X.,Hwang, J. Y.,Seo, J. Y.,Ko, Y. H.,Lee, B. R.,Lee, S. Y. Springer Science + Business Media 2016 Psychophamacology Vol.233 No.8

<P>Phentermine is structurally similar to methamphetamine and is widely used as an anti-obesity drug in the USA and many other countries. The potential for reward of phentermine has been noted; however, the mechanisms of phentermine dependence have not been established. Here, we investigated the rewarding and dopaminergic behavioral responses to phentermine in mice and found that phentermine produced conditioned rewarding effects through the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway in the nucleus accumbens (NAc). The impact of phentermine was assessed using conditioned place preference (CPP) test, climbing behavior test, and western blot analysis. Phentermine 1 and 3 mg/kg (i.p.) significantly increased CPP. Phentermine, a known dopamine releaser, boosted apomorphine-induced climbing behavior in mice, and methamphetamine (i.p.) also increased apomorphine-induced dopaminergic behavior. Phentermine and methamphetamine increased the level of expression of the dopamine transporter (DAT) and phospho-Akt proteins to a similar degree in the NAc of CPP mice. To determine whether the conditioned rewarding effects of phentermine were mediated through the PI3K/Akt pathway, we assessed the effects of the Akt inhibitor LY294002 on phentermine-induced place preference and climbing behavior. LY294002 (1 and 3 mu g/site, i.c.v.) reduced phentermine-induced CPP and phentermine-increased climbing behavior. However, LY294002 did not change CPP and climbing behavior itself and also did not decrease apomorphine-induced climbing behavior in mice. Further, LY294002 decreased the phentermine-increased levels of DAT protein and phosphorylation of Akt in the NAc of CPP mice. Thus, these findings suggest that phentermine induces conditioned rewarding effects via activation of the PI3K/Akt signaling pathway in the NAc.</P>

SHRIMP U-Pb dating and geochemistry of the Cretaceous plutonic rocks in the Korean Peninsula: A new tectonic model of the Cretaceous Korean Peninsula

Kim, S.W.,Kwon, S.,Park, S.I.,Lee, C.,Cho, D.L.,Lee, H.J.,Ko, K.,Kim, S.J. Universitetsforlaget ; Elsevier Science Ltd 2016 Lithos Vol.262 No.-

<P>The Cretaceous tectonomagmatism of the Korean Peninsula was examined based on geochemical and geochronological data of the Cretaceous plutonic rocks, along with distribution of volcano-sedimentary nonmarine N- to NE-trending fault bounded sedimentary basins. We conducted sensitive high-resolution ion microprobe (SHRIMP) zircon U-Pb ages and whole-rock geochemical compositions of 21 Cretaceous plutonic rocks, together with previously published data, from the central to southern Korean Peninsula. Four age groups of plutonic rocks were identified: Group I (ca. 119-106 Ma) in the northern to central area, Group II (ca. 99-87 Ma) in the central southern area, Group III (ca. 85-82 Ma) in the central to southern area, and Group IV (ca. 76-67 Ma) in the southernmost area. These results indicate a sporadic trenchward-younging trend of the Cretaceous magmatism in the Korean Peninsula. The Group I, II, and III rocks are dominated by high-K calc-alkaline I-type rocks with rift-related A-type granitoids. In contrast, the Group IV rocks are high-K calc-alkaline I-type plutonic rocks with no A-type rocks. The geochemical signatures of the entire groups indicated LREEs (light rare earth elements) enrichments and negative Nb, Ta, and Ti anomalies, indicating normal arc magmatism. A new tectonic model of the Cretaceous Korean Peninsula was proposed based on temporal and spatial distribution of the Cretaceous plutons represented by four age groups; 1) magmatic quiescence throughout the Korean Peninsula from ca. 160 to 120 Ma, 2) intrusions of the I- and A-type granitoids in the northern and central Korean Peninsula (Group I plutonic rocks from ca. 120 to 100 Ma) resulted from the partial melting of the lower continental crust due to the rollback of the Izanagi plate expressed as the conversion from flat-lying subduction to normal subduction. The Gyeongsang nonmarine sedimentary rift basin in the Korean Peninsula and adakite magmatism preserved in the present-day Japanese Islands supported the slab rollback followed by steepening of the Izanagi plate with an injection of upwelling of the hot asthenosphere into the mantle wedge. 3) Alternating shallow (from similar to 100 to 85 Ma) to steep (from similar to 85 to 65 Ma) subduction resulted in the migration of the normal arc magmatism in the southern Korean Peninsula, expressed as the intruded I- and A-type (Group III) and I-type granitoids (Group IV), respectively. The tectonomagmatism of, the Korean Peninsula showed the unique style of evolution, different from those of South China and Japanese Islands. (C) 2016 Elsevier B.V. All rights reserved.</P>

Identification of thioredoxin domain-containing protein 17 from big-belly seahorse <i>Hippocampus abdominalis</i>: Molecular insights, immune responses, and functional characterization

Liyanage, D.S.,Omeka, W.K.M.,Yang, Hyerim,Godahewa, G.I.,Kwon, Hyukjae,Nam, Bo-Hye,Lee, Jehee Elsevier 2019 Fish & shellfish immunology Vol.86 No.-

<P><B>Abstract</B></P> <P>Thioredoxin domain-containing protein 17 (TXNDC17) is a small protein (∼14 kDa) involved in maintaining cellular redox homeostasis via a thiol-disulfide reductase activity. In this study, TXNDC17 was identified and characterized from <I>Hippocampus abdominalis</I>. The open reading frame (ORF) consisted of 369 bp and 123 amino acids. Similar to the other thioredoxins, TXNDC17 contained a conserved WCXXC functional motif. The highest spatial mRNA expressions of <I>HaTXNDC17</I> were observed in the muscle, brain, and intestine. Interestingly, the mRNA expression of <I>HaTXNDC17</I> in blood showed significant upregulation at 48 h against all the pathogen associated molecular patterns (PAMPs) and bacteria. Further, <I>HaTXNDC17</I> transcripts in the trunk kidney were significantly upregulated at 24–48 h by bacterial endotoxin lipopolysaccharides (LPS), viral mimic polyinosinic: polycytidylic acid (poly I:C), and gram-negative bacteria (<I>Edwardsiella tarda</I>). The DPPH assay showed that the radical scavenging activity varies in a concentration-dependent manner. The insulin reduction assay demonstrated a significant logarithmic relationship with the concentration of rHaTXNDC17. Moreover, FHM cells treated with recombinant HaTXNDC17 significantly enhanced cellular viability under oxidative stress. Together, these results show that HaTXNDC17 function is important for maintaining cellular redox homeostasis and that it is also involved in the immune mechanism in seahorses.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Big-belly seahorse thioredoxin domain containing protein 17 maintain redox homeostasis. </LI> <LI> TXNDC17 is ubiquitously found in cytosol and extracellular space. </LI> <LI> Thiol active CXXC conserved motif consists in HaTXNDC17. </LI> <LI> Spatial and temporal mRNA expression was evaluated. </LI> <LI> Radical scavenging ability, antioxidant activity and cellular viability were measured. </LI> </UL> </P>

Bifidobacterium bifidum ATCC 11863 에 의한 우유의 발효에 관한 연구 - 발효에 의한 유성분의 변화 -

고준수(J . S . Goh),권일경(I . K . Kwon),안종건(J . K . Ahn),윤영호(Y . H . Yoon) 한국축산학회 1988 한국축산학회지 Vol.30 No.10

This research was performed to get the informations needed to manufacture fermented milk products using bifidobacteria as starter culture. The conversion of constituents in the whole milk fermented by Bifidobacterium bifidum ATCC 11863 was investigated, and the results were compared with those by several lactic acid bacteria generally used for the fermented milk products. 1. The use of lactose varied according to the kinds of bacteria, such as B. bifidum, L. acidophilus, L. casei and S. thermophilus. When the whole milk was fermented by B. bifidum, the glucose reached 480 mg per 100 ml; while galactose reached 661 mg per 100 ml when S. thermophilus was grown in whole milk. 2. B. bifidum and L. acidophilus raised the, soluble nitrogenous compounds in whole milk after 24 hours at 37℃, however, there was little change soluble nitrogenous compounds content of whole milk by L. casei and S. thermophilus. 3. The content of free amino acids was increased by B. bifidum and L. acidophilus after 24 hours at 37℃; whereas decreased when L. casei and S. thermophilus were grown. 4. The polyacrylamide gel electrophoresis evidenced no significant change of casein but distinct changes of whey protein were observed by B. bifidum, L. acidophilus, L. casei and S. thermophilus at 37℃ after 24 hours. The change of whey protein was more noticeable when whole milk was fermented by L. acidophilus and L. casei than by B. bifidum and S. thermophilus. 5. The pyruvic acid content was decreased in whole milk after 24 hours at 37℃ by B. bifidum, L. acidophilus, L. casei and S. thermophilus. Lactic and succinic acid were produced during the fermentation of whole milk by B. bifidum, L. acidophilus and L. casei but B. bifidum produced less lactic acid than other bacteria. 6. Acetic acid was increased in the whole milk by B. bifidum, L. acidophilus and L. casei after 24 hours at 37℃. It was increased more rapidly by B. bifidum than by other bacteria; however, it was decreased during the fermentation by S. thermophilus. When B. bifidum was grown in whole milk, volatile organic acids such as propionic, isobutyric, butyric, isovaleric, valeric and caproic acids were decreased.

Electron-beam-induced reduced graphene oxide as an alternative hole-transporting interfacial layer for high-performance and reliable polymer solar cells

Kwon, S.N.,Jung, C.H.,Na, S.I. Elsevier Science 2016 ORGANIC ELECTRONICS Vol.34 No.-

<P>We demonstrate an eco-friendly, simple, and cost-effective method for manufacturing reduced graphene oxide (GO) induced with electron-beam irradiation, and we investigate the feasibility of the electronbeam-induced reduced GO (ERGO) as a hole-transporting interfacial layer in polymer solar cells (PSCs). In addition, the chemical composition, conductivity, work-function, and morphology of ERGOs with various absorbed doses were systematically investigated. The analytical results revealed that the reduced GO (RGO) was successfully prepared using electron-beam irradiation, and the electrical conductivity of ERGO was increased (up to 18.3 S/cm) with increasing the amount of absorbed dose. The PSCs with the ERGO as a hole-transporting interfacial layer exhibited comparable cell performance (3.52 +/- 0.08% of power conversion efficiency) to that of the conventional PSCs with the poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS), and they had better stability than the PEDOT:PSS-based PSCs. From the results, we confirmed that electron-beam irradiation is an effective approach to prepare the RGO, and the ERGO was preferable to the PEDOT:PSS for high-performance and stable PSCs. (C) 2016 Elsevier B.V. All rights reserved.</P>

모음의 특성을 고려한 화자인식 시스템 구현

권영헌,이건상,김민수,양성일 漢陽大學校 自然科學硏究所 2000 自然科學論文集 Vol.19 No.-

5개의 우리말 모음 (/아/, /에/, /이/, /오/, /우/)에 대해 화자의 특징을 나타내는 256-level의 코드 북을 구성하였고 이를 HMM에 적용하여 화자인식 실험을 수행하였다. 인식실험에 사용된 특징벡터로는 10차의 cepstrum 계수를 이용하였다. To construct codebook of 256 level, 5 Korean vowels(/a/, /e/, /i/, /o/, /u/) is applied in vector quantization. Applying the codebook in HMM, speaker recognition expriment is made. The 10-order Cepstrum Coefficient is used as the feature vector.

I-SSR Markers Revealed Inconsistent Phylogeographic Patterns among Populations of Japanese Red Pines in Korea

Hong, Y.-P.,Kwon, H.-Y.,Kim, I.-S. J.D.Sauerlander's Verlag 2007 Silvae genetica Vol.56 No.1

<P><B>Abstract</B></P><P>To monitor the level and distribution pattern of genetic diversity in countrywide populations of Japanese red pines in Korea, 80 I-SSR variants were analyzed from 192 individuals in 11 populations. The previously reported data, obtained from the 8 populations of this species, were incorporated into the estimation of the population genetic statistics. Relatively higher level of genetic diversity was observed in 19 populations of Japanese red pines (mean of 0.453) than those in other tree species. From the results of AMOVA, majority of genetic diversity (92%) was allocated within populations, which brought about the moderate degree of population differentiation (ϕ<SUB>ST</SUB>= 0.08). Two genetic groups were observed from the dendrogram reconstructed by UPGMA. Overall correlation between genetic relationships and geographic affinity was inconsistent among the 19 populations. Some probable genetic disturbances, induced by either human interference or the natural process of regeneration for the species after devastation, might be responsible for the discrepancy between genetic relationships and geographical distribution of the populations. These results suggested that simple geographic or ecological grouping might not represent the genetic zone of the Korean populations of Japanese red pines, and that more careful approach should be made for designating in situ gene conservation of this species in Korea.</P>

Experimental Approach to Explosive Nucloeosynthesis with RI Beams

S. Kubono,Y. Yamaguchi,G. Amadio,S. Hayakawa,Y. Wakabayashi,Y. Kurihara,J. J. He,A. Saito,H. Fujikawa,Le Hong Khiem,M. Niikura,T. Teranishi,N. Iwasa,S. Kato,S. Nishimura,C. S. Lee,Y. K. Kwon,I. S. Hah 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.54 No.1

Experimental efforts to investigate stellar reactions under high-temperature and high density conditions have been made as a major program using the RI beams from the Center for Nuclear Study (CNS) low-energy in-flight RI beam separator (CRIB) at University of Tokyo in order to understand the evolution of the universe, as well as various stellar phenomena. Specically, two subjects of hydrogen burning are discussed here. One is a reaction study of the pp-chain and the second is of the explosive hydrogen burning, the rp-process. Some s-wave resonances have been identified by the thick target method in the crucial reaction processes in the hydrogen burning. The resonant scattering with the thick target method also succeeded in identifying inelastic resonant scattering, giving proton widths for the first excited state of the target nucleus. This provided very efficiently the reaction rate estimate for the process under high-temperature equilibrium conditions. Possibilities of the CRIB facility in near future are also briey discussed. Experimental efforts to investigate stellar reactions under high-temperature and high density conditions have been made as a major program using the RI beams from the Center for Nuclear Study (CNS) low-energy in-flight RI beam separator (CRIB) at University of Tokyo in order to understand the evolution of the universe, as well as various stellar phenomena. Specically, two subjects of hydrogen burning are discussed here. One is a reaction study of the pp-chain and the second is of the explosive hydrogen burning, the rp-process. Some s-wave resonances have been identified by the thick target method in the crucial reaction processes in the hydrogen burning. The resonant scattering with the thick target method also succeeded in identifying inelastic resonant scattering, giving proton widths for the first excited state of the target nucleus. This provided very efficiently the reaction rate estimate for the process under high-temperature equilibrium conditions. Possibilities of the CRIB facility in near future are also briey discussed.

두개의 수직격판을 가진 밀폐공간내에서의 자연대류 열전달

권순석,권용일 동아대학교 공과대학 부설 한국자원개발연구소 1991 硏究報告 Vol.15 No.1

A numerical investigation has been made of two dimensional natural convection heat transfer from a rectangular enclousure with two vertical partitions. Results have been obtained for dimensionless partition spacings, S/L〓0.2-0.8 and for dimenionless partition lengths, ℓ/L〓0.1-0.4 and also for partition materials of fiber, glass and stainless steel. 1. The dimensionless partition spacing that occurs the minimum heat transfer in a rectangular enclousure is S/L〓0.6 for fiber, S/L〓0.7 for glass and S/L〓0.5 for stainless steel. 2. AS partition spacings increase, the flow pattern in a rectangular enclousure is changed from muti-cellular flow to uni-cellular flow for fiber and glass. 3. Partition lengths with the minimum heat transfer in case of fiber and glass in a rectangular enclousure occurs at ℓ/L〓0.2 respectively.