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      • SCIESCOPUSKCI등재

        Characterization of Insertional Variation of Porcine Endogenous Retroviruses in Six Different Pig Breeds

        Jung, W.Y.,Yu, S.L.,Seo, D.W.,Jung, K.C.,Cho, I.C.,Lim, H.T.,Jin, D.I.,Lee, Jun-Heon Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.10

        Pigs may need to be exploited as xenotransplantation donors due to the shortage of human organs, tissues and cells. Porcine endogenous retroviruses (PERVs) are a significant obstacle to xenotransplantation because they can infect human cells in vitro and have the potential for transmission of unexpected pathogens to humans. In this research, 101 pigs, including four commercial breeds (23 Berkshire, 13 Duroc, 22 Landrace and 14 Yorkshire pigs), one native breed (19 Korean native pigs) and one miniature breed (10 NIH miniature pigs) were used to investigate insertional variations for 11 PERV loci (three PERV-A, six PERV-B and two PERV-C). Over 60% of the pigs harbored one PERV-A (907F8) integration and five PERV-B (B3-3G, B3-7G, 742H1, 1155D9 and 465D1) integrations. However, two PERV-A loci (A1-6C and 1347C1) and one PERV-B locus (B3-7F) were absent in Duroc pigs. Moreover, two PERV-C loci (C2-6C and C4-2G) only existed in Korean native pigs and NIH miniature pigs. The results suggest that PERV insertional variations differ among pig breeds as well as among individuals within a breed. Also, the results presented here can be used for the selection of animals that do not have specific PERV integration for xenotransplantation research.

      • SCISCIESCOPUS

        Effects of the addition of ZnO and Y<sub>2</sub>O<sub>3</sub> on the electrochemical characteristics of a Ni(OH)<sub>2</sub> electrode in nickel-metal hydride secondary batteries

        Jung, K.W.,Yang, D.C.,Park, C.N.,Park, C.J.,Choi, J. Pergamon Press ; Elsevier Science Ltd 2010 International journal of hydrogen energy Vol.35 No.23

        This study examined the effects of the addition of ZnO and Y<SUB>2</SUB>O<SUB>3</SUB> on the electrochemical characteristics of a Ni(OH)<SUB>2</SUB> electrode in nickel-metal hydride (Ni-MH) secondary batteries. The discharge capacity of the electrode was less affected by the addition of ZnO and Y<SUB>2</SUB>O<SUB>3</SUB> at a 0.2 C-rate and 25<SUP>o</SUP>C. However, the addition of Y<SUB>2</SUB>O<SUB>3</SUB> deteriorated the discharge capacity and the cycle life of the electrode by increasing the charge transfer resistance of the electrode at an increased C-rate of 1 C and 25<SUP>o</SUP>C. Under severer conditions at 1 C-rate and 60<SUP>o</SUP>C, the electrode materials were separated from the current collector and, accordingly, the discharge capacity was abruptly degraded with cycling for the electrodes comprising only 4wt% ZnO or 4wt% Y<SUB>2</SUB>O<SUB>3</SUB>. In contrast, the electrodes containing both 2wt% ZnO and 2wt% Y<SUB>2</SUB>O<SUB>3</SUB> exhibited stable discharge capacity with cycling and excellent cycle life due to the high overvoltage for oxygen evolution. The present results indicate that the addition of ZnO and Y<SUB>2</SUB>O<SUB>3</SUB> with an optimum composition suppresses oxygen evolution in the interfaces between active materials and the current collector and improves the cycle life of the electrode.

      • <i>Rhodococcus aerolatus</i> sp. nov., isolated from subarctic rainwater

        Hwang, C. Y.,Lee, I.,Cho, Y.,Lee, Y. M.,Baek, K.,Jung, Y.-J.,Yang, Y. Y.,Lee, T.,Rhee, T. S.,Lee, H. K. International Union of Microbiological Societies 2015 International journal of systematic and evolutiona Vol.65 No.2

        <P>A Gram-stain-positive, rod-shaped and non-motile strain, designated PAMC 27367<SUP>T</SUP>, was isolated from rainwater collected on the Bering Sea. Analysis of the 16S rRNA gene sequence of the strain showed an affiliation with the genus <I>Rhodococcus</I>. Phylogenetic analyses revealed that strain PAMC 27367<SUP>T</SUP> formed a robust clade with the type strains of <I>Rhodococcus rhodnii</I>, <I>Rhodococcus aetherivorans</I> and <I>Rhodococcus ruber</I> with 16S rRNA gene sequence similarities of 96.3 %, 95.8 % and 95.5 %, respectively. Cells of the strain grew optimally at 25 °C and at pH 6.5–7.0 in the presence of 0–2 % (w/v) sea salts. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and three unknown phospholipids. The major cellular fatty acids (>10 %) were iso-C<SUB>16 : 0</SUB>, C<SUB>17 : 1</SUB>ω8<I>c</I> and 10-methyl C<SUB>17 : 0</SUB>. Cell wall analysis showed that strain PAMC 27367<SUP>T</SUP> contained <I>meso</I>-diaminopimelic acid. The genomic DNA G+C content was 77.1 mol%. Based on the phylogenetic, chemotaxonomic and phenotypic data presented here, we propose a novel species with the name <I>Rhodococcus</I> <I>aerolatus</I> sp. nov., with PAMC 27367<SUP>T</SUP> ( = KCTC 29240<SUP>T</SUP> = JCM 19485<SUP>T</SUP>) as the type strain.</P>

      • The Use of Collagen Content as Determined by Spectral Domain Polarization-Sensitive Optical Coherence Tomography to Assess Colon Anastomosis Healing in a Rat Model

        Son, K.H.,Jeong, H.-W.,Jung, W.-W.,Kim, H.-S.,Lee, S.K.,Kim, K.T.,Ahn, C.B.,Park, K.Y.,Kim, B.-M.,Lee, S.H. S. Karger AG 2014 European surgical research Vol.52 No.1

        <P>Abstract</P><P><B><I>Background/Purpose:</I></B> Many studies have been undertaken to prevent anastomosis leakage of the colon, and several methods have been used to assess anastomosis healing, such as measurement of bursting pressure or hydroxyproline (a marker of collagen) content at the anastomosis site. However, these methods are inappropriate for comparing anastomosis healing at two time points in the same animals. In the present study, we measured the collagen level by spectral domain polarization-sensitive optical coherence tomography (SD-PS-OCT) to assess anastomosis healing. <B><I>Methods:</I></B> Sprague-Dawley rats were divided into groups C (saline-administered controls; study group) and M [a 5-fluorouracil (5-FU)-administered experimental group]. Immediately after end-to-end anastomosis of the colon, SD-PS-OCT images of anastomoses were taken (baseline). Animals were administered saline or 5-FU for 7 days. On the 7th postoperative day, SD-PS-OCT images were acquired, a histopathologic exam was performed, and hydroxyproline levels as well as mRNA expressions of collagen-1 and collagen-3 were measured at the anastomosis site. <B><I>Results:</I></B> Fibroblast proliferation and inflammatory cell infiltration were greater in group C than in group M. The mRNA expressions of collagen-1 and collagen-3 were substantially higher in group C. Hydroxyproline levels were higher in group M than in group C. Though collagen levels measured by SD-PS-OCT at 7 days were elevated compared with baseline in group C, no such changes were observed for group M. <B><I>Conclusion:</I></B> Collagen levels at the colon anastomosis site, measured with SD-PS-OCT, were not increased at 7 days postoperatively versus baseline when 5-FU was injected, but were increased in saline-treated controls. The measurement of collagen content by SD-PS-OCT was found to provide a good means of assessing anastomosis healing, because it allows in situ assessment of collagen contents at baseline and during the postoperative period.</P><P>© 2014 S. Karger AG, Basel</P>

      • Carbenoxolone prevents the development of fatty liver in C57BL/6-Lep <sup>ob/ob</sup> mice via the inhibition of sterol regulatory element binding protein-1c activity and apoptosis

        Dal Rhee, S.,Kim, C.H.,Seon Park, J.,Hoon Jung, W.,Bum Park, S.,Youn Kim, H.,Hwan Bae, G.,Jan Kim, T.,Young Kim, K. North-Holland ; Elsevier Science Ltd 2012 european journal of pharmacology Vol.691 No.1

        Carbenoxolone is the 3-hemisuccinate of glycyrrhetinic acid, the active principal of licorice (Glycyrrhiza glabra). It was reported that carbenoxolone improved glucose tolerance with increased insulin sensitivity in mice with high fat diet-induced obesity. In the present study, we elucidated the protective effect of carbenoxolone in fatty liver animal models of C57BL/6-Lep<SUP>ob/ob</SUP> mice through inhibition of hepatic lipogenesis and apoptosis. In addition, the potential mechanisms by which carbenoxolone could exert such protection were elucidated. Carbenoxolone was daily administrated by gavage for 28 days in C57BL/6 and C57BL/6-Lep<SUP>ob/ob</SUP> mice. Carbenoxolone prevented the plasma triglyceride and free fatty acid accumulation associated with the reduction of the expression of sterol regulatory element binding protein-1c, liver X receptor, fatty acid synthase and acethyl-CoA carboxylase in the livers of C57BL/6-Lep<SUP>ob/ob</SUP> mice. Carbenoxolone also prevented hepatic injury through anti-apoptotic action in the livers of C57BL/6-Lep<SUP>ob/ob</SUP> mice, accompanied by increased Bcl-2 expression and suppressed Bax and cytochrome c expression. As a mechanism, increased inflammatory cytokine expressions were inhibited by carbenoxolone in the fatty livers of C57BL/6-Lep<SUP>ob/ob</SUP> mice. Furthermore, carbenoxolone inhibited free fatty acid (oleate/palmitate) induced reactive oxygen species formation and reversed free fatty acid induced mitochondrial membrane depolarization in HepG2 cells. Carbenoxolone prevents the development of fatty liver by inhibiting sterol regulatory element binding protein-1c expression and activity with an anti-apoptotic mechanism via the inhibition of inflammatory cytokine and reactive oxygen species formation in the livers of C57BL/6-Lep<SUP>ob/ob</SUP> mice. It is suggested that carbenoxolone prevents the development and progression of fatty liver disease in patients with insulin resistance.

      • 돼지 卵子의 透明帶에 대한 單一클론抗體生産과 그 特性에 關한 硏究

        金鐘培,劉永春,金昌圭,權五中,鄭盛元,鄭吉生 건국대학교 동물자원연구센터 1991 動物資源硏究誌 Vol.16 No.-

        本 試驗은 單一클론抗體의 강한 特異性과 抗體性質의 不變性을 이용하여 發生學的 側面에서 哺乳動物 卵子의 透明帶의 機能과 構造를 이해하고, 또한 種特異的인 精子 受容體의 存在 및 生化學的 構造를 규명하기 위한 기초연구로서, 돼지 卵子의 透明帶를 免疫原으로 하여 BABL/c 생쥐로부터 單一클론抗體를 생산하고 그 특성을 구명하였던 바 다음과 같은 결과를 얻었다. 1) 3마리의 BABL/c 생쥐(YⅠ, YⅡ, ZI)에 돼지卵子의 透明帶를 免疫化하고, 複合抗體 生成을 확인한 후 생쥐의 脾臟細胞와 Myeloma(SP2/O-Ag14)를 polyethylene glycol를 融合을 실시한 결과 각각 25.8%, 54.5% 그리고 59.7%의 融合效率을 나타내었으며, ELISQ에 의해 陽性反應을 조사한 결과 각각 17.3%, 32.6% 그리고 6.2% 陽性反應 效率을 나타내었다. 2) YI에서 강한 陽性反應을 보인 6개의 well에 대한 cloning을 실시하고 抗體檢證을 행한 결과 20.8% ∼ 48.4%의 Cloning效率과 54.6% ∼ 82%의 陽性反應 效率을 나타내었다. 3) 강한 陽性反應을 나타낸 항체에 대해 sandwich ELISA法에 의해 isotype을 決定하였던바 2E93C(YⅠ), 3E83E7(YⅠ), 4E3(YⅡ)각각 IgG₂b, IgG₂a, IgM으로 확인되었다. 4) Isotype이 決定된 2E93C9(YⅠ), 3E84E7(YⅠ), 4E3(YⅡ)의 세포를 생쥐의 腹腔에 주사하여 얻은 腹水를 indirect ELISA法에 의해 titer를 決定한 결과 모두 1:400,000 이상의 높은 titer를 나타내었다. 5) 處理區로서 單一클론抗體의 腹水와 對照區로서 normal mouse serum이 각각 2%씩 함유된 배양액속에서 난자를 배양한 후 顯徵鏡下에서 관찰했을 때 對照區에서 배양된 난자의 표면은 정상적인 형태를 나타냈으나 處理區에서 배양된 卵子는 표면에 뚜렷한 沈澱層을 형성하였다. 6) 處理區와 對照區 卵子를 Rabbit anti-mouse IgG-FITC가 1% 함유된 배양액속에서 배양하고 洗滌한 후 螢光顯徵鏡下에서 관찰한 바 處理區의 卵子는 透明帶 주위에서 螢光이 나타났으나, 對照區에서는 나타나지 않았다. This study was carried out ot produce and characterize monoclonal antibodies against porcine zona pellucida, and undertaken as a basic study to develop immunocontraceptive vaccine and to investigate the function of zana pellucida in early fertilization process. The results obtained were summarized as follows: 1. Spleen cells of three BALB/C mice(YⅠ, YⅡ and ZI) which were immunized with porcine zona pelucida were fused with myeloma cells(SP2/O-Ag14) by polyethylene glycol. At the result of fusion, fusion efficiency was 25.8 , 54.5% and 59.7% and positive efficiency 17.3%, 32.6% and 6.2%, respectively. 2. Cloning efficiency was shown to be from 20.8% to 48.4% and positive efficiency of them were 54.6% to 82%. 3. Sub-isotypes of three strong positive antibodies, 2E93C(YⅠ), 3E83E7(YⅠ) and 4E3(YⅡ) were determined by sandwich ELISA method and shown to be as IgG2b, IgH2a and IgM, respectively. 4. The titers of three ascitic fluids containing antibodies, 2E93C9(YⅠ), 3E84E7(YⅠ) and 4E3(YⅡ) were determined by indirect ELISA and all of them showed above 1:400,000. 5. The layer of precipitate was observed on the zona incubated with medium containing 2% ascitic fluid of monoclonal antibody while the eggs treated with 2% normal mouse serum did not. 6. Porcine eggs incubated with medium containing 2% ascitic fluid of monoclonal antibody and followed by subsequent incubation with Rabbit anti-mouse IgG-FITC conjugate showed strong fluorescent light on the zona surface while the zona of normal mouse serum-treated eggs did not show fluorescence.

      • SCISCIESCOPUS

        Enhanced adipogenic differentiation and reduced collagen synthesis induced by human periodontal ligament stem cells might underlie the negative effect of recombinant human bone morphogenetic protein‐2 on periodontal regeneration

        Song, D‐,S.,Park, J‐,C.,Jung, I‐,H.,Choi, S‐,H.,Cho, K,S.,Kim, C,K.,Kim, C,S. Blackwell Publishing Ltd 2011 Journal of periodontal research Vol.46 No.2

        <P> <I>Song D‐S, Park J‐C, Jung I‐H, Choi S‐H, Cho K‐S, Kim C‐K, Kim C‐S. Enhanced adipogenic differentiation and reduced collagen synthesis induced by human periodontal ligament stem cells might underlie the negative effect of recombinant human bone morphogenetic protein‐2 on periodontal regeneration. J Periodont Res 2011; 46: 193–203. © 2010 John Wiley & Sons A/S</I> </P><P><B>Background and Objective: </B> Recombinant human bone morphogenetic protein‐2 (rhBMP‐2) is a potent inducer for the regeneration of mineralized tissue, but has a limited effect on the regeneration of cementum and periodontal ligament (PDL). The aim of the present study was to determine the effects of rhBMP‐2 on the <I>in vitro</I> and <I>in vivo</I> biologic activity of well‐characterized human PDL stem cells (hPDLSCs) and to elucidate the underlying mechanism of minimal periodontal regeneration by rhBMP‐2.</P><P><B>Material and Methods: </B> hPDLSCs were isolated and cultured, and then transplanted into an ectopic subcutaneous mouse model using a carrier treated either with or without rhBMP‐2. Comprehensive histologic, histometric and immunohistochemical analyses were performed after an 8‐wk healing period. The effects of rhBMP‐2 on the adipogenic and osteogenic/cementogenic differentiation of hPDLSCs were also evaluated. The effect of rhBMP‐2 on both soluble and insoluble collagen synthesis was analyzed, and the expression of mRNA and protein for collagen types I, II, III and V was assessed.</P><P><B>Results: </B> In the present study, rhBMP‐2 promoted both adipogenic and osteogenic/cementogenic differentiation of hPDLSCs <I>in vitro</I>, and the <I>in vivo</I> potential of hPDLSCs to form mineralized cementum and organized PDL tissue was down‐regulated following treatment with rhBMP‐2. Collagen synthesis, which plays a crucial role in the regeneration of cementum and the periodontal attachment, was significantly reduced, with associated modification of the relevant mRNA and protein expression profiles.</P><P><B>Conclusion: </B> In summary, the findings of the present study suggest that enhanced adipogenic differentiation and inhibition of collagen synthesis by hPDLSCs appear to be partly responsible for the minimal effect of rhBMP‐2 on cementum and PDL tissue regeneration by hPDLSCs.</P>

      • KCI등재후보

        PET 영상의 잡음개선을 위한 적응적 공간 필터 개발

        우상근,최용,임기천,송태용,정진호,이경한,김상은,최연성,박장춘,김병태,Woo, S. K.,Choi, Y.,Im, K. C.,Song, T. Y.,Jung, J. H.,Lee, K. H.,Kim, S. E.,Choe, Y. S.,Park, C. C.,Kim, B. T. 대한의용생체공학회 2002 의공학회지 Vol.23 No.3

        양전자방출단층촬영기(Positron emission tomography, PET) 영상 개선을 위하여 적응적 공간 필터를 개발하였으며. 개발한 필터의 성능을 시뮬레이션데이터. 모형 PET 영상과 환자 PET 영상을 이용하여 평가하였다. 경계화소로 검출된 화소와 윈도우내의 모든 화소값이 동일한 화소는 보존하고. 그 외 화소에 대하여 2:7:2 비율로 가중치를 주어 정열한 후 중앙의 9개 화소에 대한 평균값으로 대치하였다. 경계화소를 검출하기 위하여 두 개의 임계값(TH7, TH2)을 이용하였으며. 다음의 조건을 만족하면 경계화소로 판단하였다 . THl ($pix_max{\times}0.1/log_2(NPM)$, NPM :주변값중 최상위 값과 최하위 값을 제외한 주변값들의 평균) 보다 작은 ADs (중앙값과 주변값의 차에 대한 절대값) 개수는 8-k이고. TH2 ($NPM{\times}0.1$) 보다 큰 ADs 개수는 k. 여기서 k는 2, 3 ‥‥ 6의 값을 가진다 성능평가 결과 이 연구에서 제안한 필터가 가우시안 필터, 가중메디안 필터, 부분집합평균메디안 필터 등과 비교하여 우수한 성능을 제공하는 것을 관찰하였다. 본 논문에서 개발한 간단한 적응적 공간 필터는 공간 분해능 저하는 최소화하면서 균일도와 대조도를 향상시키는데 효과적 이여서 정확한 PET 영상 해석에 기여할 것으로 기대된다 A spatially adaptive falter was formulated to imrove PET image qualify and the Performance of the filter was evaluated using simulation and phantom and human PET studies. In the proposed filter. if a pixel was identified as the edge Pixel, the Pixel value was Preserved. Otherwise a Pixel was replaced by the mean of the pixel values weighted by 2:7: 2. A Pixel was identified as the edge Pixel. if it satisfies the following conditions : the number of ADs (absolute difference between center and neighborhood pixels) which is smaller than THl (($pix_max{\times}0.1/log_2(NPM)$, NPM : mean of 6 neighborhood pixels excluding minimum and maximum) is 8-k and the number of ADs which is lager than TH2 ($NPM{\times}0.1$) is k. where k : 2, 3, …, 6. The results of this study demonstrate the superior performance of the Proposed titter compared to Gaussian fitter, weight median filter and subset averaged median filter. The proposed tittering method is simple but effective in increasing uniformity and contrast with minimal degradation of spatial resolution of PET images and thus. is expected to Provide improved diagnositc quality PET images .

      • KCI등재SCIESCOPUS

        Flexible thermoelectric generator with polydimethyl siloxane in thermoelectric material and substrate

        Jung, K.K.,Jung, Y.,Choi, C.J.,Lee, J.M.,Ko, J.S. Elsevier 2016 Current Applied Physics Vol.16 No.10

        <P>In this paper, the fabrication and characterization of a flexible thermoelectric generator (TEG) is presented. Bismuth telluride powder (Bi/Te) is utilized as p- and n-type thermoelectric materials, and carbon nanotubes (CNTs) are used to enhance electrical conductivity. Both the CNTs and bismuth telluride (Bi/Te) powder are mixed with a solution of polydimethyl siloxane (PDMS) as a precursor. The same PDMS used for the hybrid thermoelectric materials is also used as the substrate, making the TEG flexible and increasing its stability. The Seebeck coefficients of the fabricated p- and n-type thermoelectric materials are 143 and -174 mu V/K, respectively. The output voltage of the fabricated device is 920 mV and the generated power is 570 mu W/cm(2) with a temperature difference of 60 degrees C. The fabricated TEG maintains its performance level during bending reliability tests on a curvature with a radius as small as 5 mm, and after more than 1000 repetitions of bending on a curvature with a radius of 20 mm. (C) 2016 Published by Elsevier B.V.</P>

      • Growth characteristics and electrical properties of SiO2 thin films prepared using plasma-enhanced atomic layer deposition and chemical vapor deposition with an aminosilane precursor

        Jung, H.,Kim, W. H.,Oh, I. K.,Lee, C. W.,Lansalot-Matras, C.,Lee, S. J.,Myoung, J. M.,Lee, H. B.,Kim, H. Springer Science + Business Media 2016 JOURNAL OF MATERIALS SCIENCE - Vol.51 No.11

        <P>The deposition of high-quality SiO2 films has been achieved through the use of both plasma-enhanced chemical vapor deposition (PE-CVD) and plasma-enhanced atomic layer deposition (PE-ALD) methods using H2Si[N(C2H5)(2)](2) as a Si precursor. We systematically investigated growth characteristics, chemical compositions, and electrical properties of PE-CVD SiO2 prepared under various deposition conditions. The SiO2 films prepared using PE-CVD showed high purity and good stoichiometry with a dielectric constant of similar to 4. In addition, the PE-ALD process of the SiO2 films exhibited well-saturated and almost linear growth characteristics of similar to 1.3 cycle(-1) without notable incubation cycles, producing pure SiO2 films. Electrical characterization of metal-oxide silicon capacitor structures prepared with each SiO2 film showed that PE-ALD SiO2 films had relatively lower leakage currents than PE-CVD SiO2 films. This might be a result of the saturated surface reaction mechanism of PE-ALD, which allows a smooth surface in comparison with PE-CVD method. In addition, the dielectric properties of both SiO2 films were further evaluated in the structures of In-Ga-Zn-O thin-film transistors, and they both showed good device performances in terms of high I (on) - I (off) ratios (> 10(8)) and low off-currents (< 10(-11) A). However, based on the negative bias stress reliability test, it was found that PE-ALD SiO2 showed better reliability against a negative V (th) shift than PE-CVD SiO2, which might also be understood from its smoother channel/insulator interface generation at the interface.</P>

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