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>

Production of d-psicose from d-fructose by whole recombinant cells with high-level expression of d-psicose 3-epimerase from Agrobacterium tumefaciens

Park, C.S.,Park, C.S.,Shin, K.C.,Oh, D.K. Society for Bioscience and Bioengineering, Japan ; 2016 Journal of bioscience and bioengineering Vol.121 No.2

<P>The specific activity of recombinant Escherichia coli cells expressing the double-site variant (133L-S213C) D-psicose 3-epimerase (DPEase) from Agrobacterium tumefaciens was highest at 24 h of cultivation time in Terrific Broth (TB) medium among the media tested. The contents of crude protein and DPEase in recombinant cells at 24 h were 37.0 and 8.6% (w/w), respectively, indicating that the enzyme was highly expressed. The reaction conditions for the production of D-psicose from D-fructose by whole recombinant cells with the highest specific activity were optimal at 60 degrees C, pH 8.5, 4 g/l cells, and 700 g/l D-fructose. Under these conditions, whole recombinant cells produced 230 g/I D-psicose after 40 min, with a conversion yield of 33% (w/w), a volumetric productivity of 345 g/l/h, and a specific productivity of 86.2 g/g/h. These are the highest conversion yield and volumetric and specific productivities of D-psicose from D-fructose by cells reported thus far. (C) 2015, The Society for Biotechnology, Japan. All rights reserved.</P>

Substrate specificity of a recombinant d-lyxose isomerase from Providencia stuartii for monosaccharides

Kwon, H.J.,Yeom, S.J.,Park, C.S.,Oh, D.K. Society for Bioscience and Bioengineering, Japan ; 2010 Journal of bioscience and bioengineering Vol.110 No.1

The specific activity and catalytic efficiency (k<SUB>cat</SUB>/K<SUB>m</SUB>) of the recombinant putative protein from Providencia stuartii was the highest for d-lyxose among the aldose substrates, indicating that it is a d-lyxose isomerase. Gel filtration analysis suggested that the native enzyme is a dimer with a molecular mass of 44 kDa. The maximal activity for d-lyxose isomerization was observed at pH 7.5 and 45 <SUP>o</SUP>C in the presence of 1 mM Mn<SUP>2+</SUP>. The enzyme exhibited high isomerization activity for aldose substrates with the C2 and C3 hydroxyl groups in the left-hand configuration, such as d-lyxose, d-mannose, l-ribose, d-talose, and l-allose (listed in decreasing order of activity). The enzyme exhibited the highest activity for d-xylulose among all pentoses and hexoses. Thus, d-lyxose was produced at 288 g/l from 500 g/l d-xylulose by d-lyxose isomerase at pH 7.5 and 45 <SUP>o</SUP>C for 2 h, with a conversion yield of 58 % and a volumetric productivity of 144 g l<SUP>-1</SUP> h<SUP>-1</SUP>. The observed k<SUB>cat</SUB>/K<SUB>m</SUB> (920 mM<SUP>-1</SUP> s<SUP>-1</SUP>) of P. stuartiid-lyxose isomerase for d-xylulose is higher than any of the k<SUB>cat</SUB>/K<SUB>m</SUB> values previously reported for sugar and sugar phosphate isomerases with monosaccharide substrates. These results suggest that the enzyme will be useful as an industrial producer of d-lyxose.

Fatigue performance of deepwater SCR under short-term VIV considering various S-N curves

Kim, D.K.,Choi, H.S.,Shin, C.S.,Liew, M.S.,Yu, S.Y.,Park, K.S. Techno-Press 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.53 No.5

In this study, a method for fatigue performance estimation of deepwater steel catenary riser (SCR) under short-term vortex-induced vibration was investigated for selected S-N curves. General tendency between S-N curve capacity and fatigue performance was analysed. SCRs are generally used to transport produced oil and gas or to export separated oil and gas, and are exposed to various environmental loads in terms of current, wave, wind and others. Current is closely related with VIV and it affects fatigue life of riser structures significantly. In this regards, the process of appropriate S-N curve selection was performed in the initial design stage based on the scale of fabrication-related initial imperfections such as welding, hot spot, crack, stress concentration factor, and others. To draw the general tendency, the effects of stress concentration factor (SCF), S-N curve type, current profile, and three different sizes of SCRs were considered, and the relationship between S-N curve capacity and short-term VIV fatigue performance of SCR was derived. In case of S-N curve selection, DNV (2012) guideline was adopted and four different current profiles of the Gulf of Mexico (normal condition and Hurricane condition) and Brazil (Amazon basin and Campos basin) were considered. The obtained results will be useful to select the S-N curve for deepwater SCRs and also to understand the relationship between S-N curve capacity and short-term VIV fatigue performance of deepwater SCRs.

적층조건별 물성 예측을 위한 DIGIMAT 활용

박수빈(S.B, Park),우영한(Y.H, Woo),허민도(M.D, Heo),문지훈(J.H, Mun) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.4

본 연구에서는 구조재로 널리 사용되는 탄소섬유강화플라스틱 복합재 적층조건별 인장, 압축 물성을 가상분석 하였다. 해석 수행에 앞서 필요한 물성 추출을 위해 0 도 인장물성, 압축물성과 45 도 전단물성, 복합재 부피분율, 밀도를 시험·측정하였으며, 해당 값을 바탕으로 가상분석을 진행하였다. 해석을 위한 시편은 Toray 3K Twill, Epoxy(금호피앤비화학, KER9610, KCA9630), 4ply 적층 후 진공백 성형으로 120 도에서 30min 간 경화를 진행하였다. 인장시험은 ASTM D3039, 압축시험은 ASTM D6641, 45 도 전단시험은 ASTM D3518, 부피분율은 ASTM D3171 규격에 따라 시험하였으며, 인장강도 600.85MPa, 인장 modulus 59.23GPa, 압축강도 368.88MPa, 압축modulus 48.56GPa, 전단강도 80.08MPa, 전단modulus 8.01GPa, 부피분율 49.7%의 값을 확인하였다. 해석 시 적층 조건으로는 Trunk Lid Outer에 사용되는 재료이기 때문에 symmetric 한 적층 패턴으로 진행하였으며, [0/45]_s, [0/0/45]_s, [45/0/45]_s, [0], [45]으로 가상분석을 진행하였다. 0 도 인장물성의 경우 시험 값이 해석 값보다 조금 더 높게 나타났으나, 이는 수지 물성 입력 시험 값이 아닌 유사한 수치를 넣어 차이가 있는 것으로 판단되며, 정확한 해석을 위해서는 해당 값을 직접 측정하여 반영해야 한다. 압축의 경우 해석 값과 유사하게 나왔는데 이는 압축의 경우 수지보다 섬유 물성에 크게 작용하기 때문인 것으로 사료되어진다. In this study, the tensile and compressive properties of carbon fiber reinforced plastic composites widely used as structural materials for each lamination condition were virtually analyzed. In order to extract the required physical properties before performing the analysis, the 0 degree tensile property, the compressive property and the 45 degree shear property, the volume fraction of the composite material, and the density were tested and measured, and a virtual analysis was conducted based on the corresponding values. The specimens for analysis were Toray 3K Twill, Epoxy (Kumho P&B Chemical, KER9610, KCA9630), 4ply laminated and then cured at 120 degrees for 30 minutes by vacuum bag forming. The tensile test was ASTM D3039, the compression test was ASTM D6641, the 45 degree shear test was ASTM D3518, the volume fraction was tested according to the ASTM D3171 standard. , Shear strength of 80.08 MPa, shear modulus of 8.01 GPa, and volume fraction of 49.7% were confirmed. In the analysis, the lamination condition was a symmetric lamination pattern because it was a material used for the trunk lid outer, and [0/45]_s, [0/0/45]_s, [45/0/45]_s, [0 ], [45] for virtual analysis. In the case of the 0 degree tensile property, the test value was slightly higher than the analysis value, but it is judged that there is a difference by putting a similar value rather than the resin property input test value. do. In the case of compression, the result was similar to the analysis value, which is believed to be because the compression has a greater effect on fiber properties than resin.

Hierarchical 3D ZnIn₂S₄/graphene nano-heterostructures: their <i>in situ</i> fabrication with dual functionality in solar hydrogen production and as anodes for lithium ion batteries

Kale, Sayali B.,Kalubarme, Ramchandra S.,Mahadadalkar, Manjiri A.,Jadhav, Harsharaj S.,Bhirud, Ashwini P.,Ambekar, Jalinder D.,Park, Chan-Jin,Kale, Bharat B. The Royal Society of Chemistry 2015 Physical Chemistry Chemical Physics Vol.17 No.47

<P>Hierarchical 3D ZnIn2S4/graphene (ZnIn2S4/Gr) nano-heterostructures were successfully synthesized using an in-situ hydrothermal method. The dual functionality of these nano-heterostructures i.e. for solar hydrogen production and lithium ion batteries has been demonstrated for the first time. The ZnIn2S4/Gr nano-heterostructures were optimized by varying the concentrations of graphene for utmost hydrogen production. An inspection of the structure shows the existence of layered hexagonal ZnIn2S4 wrapped in graphene. The reduction of graphene oxide (GO) to graphene was confirmed by Raman and XPS analyses. The morphological analysis demonstrated that ultrathin ZnIn2S4 nanopetals are dispersed on graphene sheets. The optical study reveals the extended absorption edge to the visible region due to the presence of graphene and hence is used as a photocatalyst to transform H2S into eco-friendly hydrogen using solar light. The ZnIn2S4/Gr nano-heterostructure that is comprised of graphene and ZnIn2S4 in a weight ratio of 1 : 99 exhibits enhanced photocatalytically stable hydrogen production i.e. B6365 mmole h(-1) under visible light irradiation using just 0.2 g of nano-heterostructure, which is much higher as compared to bare hierarchical 3D ZnIn2(S4). The heightened photocatalytic activity is attributed to the enhanced charge carrier separation due to graphene which acts as an excellent electron collector and transporter. Furthermore, the usage of nano-heterostructures and pristine ZnIn2S4 as anodes in lithium ion batteries confers the charge capacities of 590 and 320 mA h g(-1) after 220 cycles as compared to their initial reversible capacities of 645 and 523 mA h g(-1), respectively. These nano-heterostructures show high reversible capacity, excellent cycling stability, and high-rate capability indicating their potential as promising anode materials for LIBs. The excellent performance is due to the nanostructuring of ZnIn2S4 and the presence of a graphene layer, which works as a channel for the supply of electrons during the charge-discharge process. More significantly, their dual functionality in energy generation and storage is quite unique and commendable.</P>

Raised Source-Drain Transistors in a Cell and Support Area with Co-Silicide for 88-nm DRAM Technology and Beyond

Y.M. Choi,B.J. Park,D.H. Kim,D.I. Kim,D.S. Hwang,H. K. Hwang,H.J. Kim,H.S. Kim,I.B. Chung,J.M. Park,J.W. Lee,J.Y. Kim,Kinam Kim,M.H. Jo,정문영,N.J. Kang,S.E. Kim,Y.J. Park,Y.S. Hwang 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.44 No.1

Full integration of a 512-Mb dynamic random access memory (DRAM) using both a raised sourcedrain (S/D) in a cell and a support area with additional Co silicidation in the support area is successfully performed for the first time at an 88-nm technology node. The Co-silicided support transistors in the DRAM circuit can be made by using the silicidation-blocking-layer method which keeps the cell array from silicidation. Raised S/D transistors using Si selective epitaxial growth (SEG) demonstrate good short-channel eect (SCE) immunity and a Co-silicided S/D in the support transistors exhibits an excellent current driving capability and reduced S/D sheet resistance, even for very small dimensions.

Vitamin D deficiency impairs glucose-stimulated insulin secretion and increases insulin resistance by reducing PPAR-γ expression in nonobese Type 2 diabetic rats

Park, S.,Kim, D.S.,Kang, S. Butterworths ; Elsevier Science Ltd 2016 The Journal of nutritional biochemistry Vol.27 No.-

<P>Human studies have provided relatively strong associations of poor vitamin D status with Type 2 diabetes but do not explain the nature of the association. Here, we explored the physiological pathways that may explain how vitamin D status modulates energy, lipid and glucose metabolisms in nonobese Type 2 diabetic rats. Goto-Kakizaki (GK) rats were fed high-fat diets containing 25 (VD-low), 1000 (VD-normal) or 10,000 (VD-high) cholecalciferol-IU/kg diet for 8 weeks. Energy expenditure, insulin resistance, insulin secretory capacity and lipid metabolism were measured. Serum 25-OH-D levels, an index of vitamin D status, increased dose dependently with dietary vitamin D. VD-low resulted in less fat oxidation without a significant difference in energy expenditure and less lean body mass in the abdomen and legs comparison to the VD-normal group. In comparison to VD-low, VD-normal had lower serum triglycerides and intracellular fat accumulation in the liver and skeletal muscles which was associated with down-regulation of the mRNA expressions of sterol regulatory element binding protein-1c and fatty acid synthase and up-regulation of gene expressions of peroxisome proliferator-activated receptors (PPAR)-alpha and carnitine palmitoyltransferase-1. In euglycemic hyperinsulinemic clamp, whole-body and hepatic insulin resistance was exacerbated in the VD-low group but not in the VD-normal group, possibly through decreasing hepatic insulin signaling and PPAR-gamma expression in the adipocytes. In 3T3-L1 adipocytes 1,25-(OH)(2)-D (10 nM) increased triglyceride accumulation by elevating PPAR-gamma expression and treatment with a PPAR-gamma antagonist blocked the triglyceride deposition induced by 1,25-(OH)2-D treatment. VD-low impaired glucose-stimulated insulin secretion in hyperglycemic clamp and decreased beta-cell mass by decreasing beta-cell proliferation. In conclusion, vitamin D deficiency resulted in the dysregulation of glucose metabolism in GK rats by simultaneously increasing insulin resistance by decreasing adipose PPAR-gamma expression and deteriorating beta-cell function and mass. (C) 2015 Elsevier Inc. All rights reserved.</P>

Peroxiredoxin II promotes hepatic tumorigenesis through cooperation with Ras/Forkhead box M1 signaling pathway

Park, Y-H,Kim, S-U,Kwon, T-H,Kim, J-M,Song, I-S,Shin, H-J,Lee, B-K,Bang, D-H,Lee, S-J,Lee, D-S,Chang, K-T,Kim, B-Y,Yu, D-Y Macmillan Publishers Limited 2016 Oncogene Vol.35 No.27

<P>The current study was carried out to define the involvement of Peroxiredoxin (Prx) II in progression of hepatocellular carcinoma (HCC) and the underlying molecular mechanism(s). Expression and function of Prx II in HCC was determined using H-ras(G12V)-transformed HCC cells (H-ras(G12V)-HCC cells) and the tumor livers from H-ras(G12V)-transgenic (Tg) mice and HCC patients. Prx II was upregulated in H-ras(G12V)-HCC cells and H-ras(G12V)-Tg mouse tumor livers, the expression pattern of which highly similar to that of forkhead Box M1 (FoxM1). Moreover, either knockdown of FoxM1 or site-directed mutagenesis of FoxM1-binding site of Prx II promoter significantly reduced Prx II levels in H-ras(G12V)-HCC cells, indicating FoxM1 as a direct transcription factor of Prx II in HCC. Interestingly, the null mutation of Prx II markedly decreased the number and size of tumors in H-ras(G12V)-Tg livers. Consistent with this, knockdown of Prx II in H-ras(G12V)-HCC cells reduced the expression of cyclin D1, cell proliferation, anchorage-independent growth and tumor formation in athymic nude mice, whereas overexpression of Prx II increased or aggravated the tumor phenotypes. Importantly, the expression of Prx II was correlated with that of FoxM1 in HCC patients. The activation of extracellular signal-related kinase (ERK) pathway and the expression of FoxM1 and cyclin D1 were highly dependent on Prx II in H-ras(G12V)-HCC cells and H-ras(G12V)-Tg livers. Prx II is FoxM1-dependently- expressed antioxidant in HCC and function as an enhancer of Ras(G12V) oncogenic potential in hepatic tumorigenesis through activation of ERK/FoxM1/cyclin D1 cascade.</P>

d-pinitol regulates Th1/Th2 balance via suppressing Th2 immune response in ovalbumin-induced asthma

Lee, J.S.,Lee, C.M.,Jeong, Y.I.,Jung, I.D.,Kim, B.H.,Seong, E.Y.,Kim, J.I.,Choi, I.W.,Chung, H.Y.,Park, Y.M. North-Holland Pub ; Elsevier Science Ltd 2007 FEBS letters Vol.581 No.1

d-pinitol has been demonstrated to exert insulin-like and anti-inflammatory activities. However, its anti-allergic effect in the Th1/Th2 immune response is poorly understood. Recently, it was shown that T-bet and GATA-3 are master Th1 and Th2 regulatory transcription factors. In this study, we have attempted to determine whether d-pinitol regulates Th1/Th2 cytokine production, T-bet and GATA-3 gene expression in OVA-induced asthma model mice. We also examined to ascertain whether d-pinitol could influence eosinophil peroxidase (EPO) activity. After being sensitized and challenged with ovalbumin (OVA) showed typical asthmatic reactions. These reactions included an increase in the number of eosinophils in bronchoalveolar lavage (BAL) fluid, an increase in inflammatory cell infiltration into the lung tissue around blood vessels and airways, airway luminal narrowing, and the development of airway hyper-responsiveness (AHR). The administration of d-pinitol before the last airway OVA challenge resulted in a significant inhibition of all asthmatic reactions. Accordingly, this study may provide evidence that d-pinitol plays a critical role in the amelioration of the pathogenetic process of asthma in mice. These findings provide new insight into the immunopharmacological role of d-pinitol in terms of its effects in a murine model of asthma, and also broaden current perspectives in our understanding of the immunopharmacological functions of d-pinitol.