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.

An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements.

King, J D,Strait, E J,Boivin, R L,Taussig, D,Watkins, M G,Hanson, J M,Logan, N C,Paz-Soldan, C,Pace, D C,Shiraki, D,Lanctot, M J,La Haye, R J,Lao, L L,Battaglia, D J,Sontag, A C,Haskey, S R,Bak, J G American Institute of Physics 2014 Review of scientific instruments Vol.85 No.8

<P>The DIII-D tokamak magnetic diagnostic system [E. J. Strait, Rev. Sci. Instrum. 77, 023502 (2006)] has been upgraded to significantly expand the measurement of the plasma response to intrinsic and applied non-axisymmetric '3D' fields. The placement and design of 101 additional sensors allow resolution of toroidal mode numbers 1 n 3, and poloidal wavelengths smaller than MARS-F, IPEC, and VMEC magnetohydrodynamic model predictions. Small 3D perturbations, relative to the equilibrium field (10(-5) < δB/B0 < 10(-4)), require sub-millimeter fabrication and installation tolerances. This high precision is achieved using electrical discharge machined components, and alignment techniques employing rotary laser levels and a coordinate measurement machine. A 16-bit data acquisition system is used in conjunction with analog signal-processing to recover non-axisymmetric perturbations. Co-located radial and poloidal field measurements allow up to 14.2 cm spatial resolution of poloidal structures (plasma poloidal circumference is ~500 cm). The function of the new system is verified by comparing the rotating tearing mode structure, measured by 14 BP fluctuation sensors, with that measured by the upgraded B(R) saddle loop sensors after the mode locks to the vessel wall. The result is a nearly identical 2/1 helical eigenstructure in both cases.</P>

비타민 D3 의 경구투여 또는 자외선 조사가 브로일러 병아리의 증체 및 비타민 D3 대사에 미치는 영향

장윤환(Y . H . Chiang),황선일(S . I . Hwang),김중달(J . D . Kim),M . F . Holick(M . F . Holick) 한국영양사료학회 1995 韓國營養飼料學會誌 Vol.19 No.6

Measurement of vector boson plusD*(2010)+meson production inp¯pcollisions ats=1.96 TeV

Aaltonen, T.,Amerio, S.,Amidei, D.,Anastassov, A.,Annovi, A.,Antos, J.,Apollinari, G.,Appel, J. A.,Arisawa, T.,Artikov, A.,Asaadi, J.,Ashmanskas, W.,Auerbach, B.,Aurisano, A.,Azfar, F.,Badgett, W.,Bae American Physical Society 2016 Physical Review D Vol.93 No.5

<P>A measurement of vector boson (V) production in conjunction with a D*(2010)(+) meson is presented. Using a data sample corresponding to 9.7 fb(-1) of proton-antiproton collisions at center-of-mass energy root s = 1.96 TeV produced by the Fermilab Tevatron, we reconstruct V + D*+ samples with the CDF II detector. The D*+ is fully reconstructed in the D*(2010)(+) -> D-0 (-> K-pi(+))pi(+) decay mode. This technique is sensitive to the associated production of vector boson plus charm or bottom mesons. We measure the ratio of production cross sections sigma(W + D*) = sigma(W) = [1.75 +/- 0.13(stat) +/- 0.09(stat)]% and sigma(Z + D*)/sigma(Z) = [1.5 +/- 0.4(stat) +/- 0.2(stat)]% and perform a differential measurement of d sigma(W + D*)/dp(T)(D*). Event properties are utilized to determine the fraction of V + D*(2010)(+) events originating from different production processes. The results are in agreement with the predictions obtained with the PYTHIA program, limiting possible contribution from non-standard-model physics processes.</P>

RF 스위치 적용을 위한 박막 PZT 엑추에이터의 d<SUB>31</SUB> 구동과 d<SUB>33</SUB> 구동 특성 비교

신민재(M. J. Shin),서영호(Y. H. Seo),최두선(D-S. Choi),황경현(K-H. Hwang) 한국정밀공학회 2006 한국정밀공학회 학술발표대회 논문집 Vol.2006 No.5월

In this work, we present the comparison between d<SUB>31</SUB> and d<SUB>33</SUB> mode characterization using the PZT micro-actuator for large displacement. The PZT micro-actuator consisted of Si, PZT, and Pt layer on SOI wafer. The electrode shapes were laminated and interdigitated for d<SUB>31</SUB> and d<SUB>33</SUB> mode, respectively. In order to characterize the actuation mode, we measured the displacement using laser interferometer. The maximum displacement of d<SUB>31</SUB> mode was 12.2㎛ at 10V, the actuation characterization of d<SUB>31</SUB> was better than that of d<SUB>33</SUB> mode. We estimated that displacement of d<SUB>33</SUB> mode would be larger than that of d<SUB>31</SUB> above 30V.

Protein Profile in Corpus Luteum during Pregnancy in Korean Native Cows

Chung, H.J.,Kim, K.W.,Han, D.W.,Lee, H.C.,Yang, B.C.,Chung, H.K.,Shim, M.R.,Choi, M.S.,Jo, E.B.,Jo, Y.M.,Oh, M.Y.,Jo, S.J.,Hong, S.K.,Park, J.K.,Chang, W.K. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.11

Steroidogenesis requires coordination of the anabolic and catabolic pathways of lipid metabolism, but the profile of proteins associated with progesterone synthesis in cyclic and pregnant corpus luteum (CL) is not well-known in cattle. In Experiment 1, plasma progesterone level was monitored in cyclic cows (n = 5) and pregnant cows (n = 6; until d-90). A significant decline in the plasma progesterone level occurred at d-19 of cyclic cows. Progesterone level in abbatoir-derived luteal tissues was also determined at d 1 to 5, 6 to 13 and 14 to 20 of cyclic cows, and d-60 and -90 of pregnant cows (n = 5 each). Progesterone level in d-60 CL was not different from those in d 6 to 13 CL and d-90 CL, although the difference between d 6 to 13 and d-90 was significant. In Experiment 2, protein expression pattern in CL at d-90 (n = 4) was compared with that in CL of cyclic cows at d 6 to 13 (n = 5). Significant changes in the level of protein expression were detected in 32 protein spots by two-dimensional polyacrylamide gel electrophoresis (2-DE), and 23 of them were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Six proteins were found only in pregnant CL, while the other 17 proteins were found only in cyclic CL. Among the above 6 proteins, vimentin which is involved in the regulation of post-implantation development was included. Thus, the protein expression pattern in CL was disorientated from cyclic luteal phase to mid pregnancy, and alterations in specific CL protein expression may contribute to the maintenance of pregnancy in Korean native cows.

Exendin-4 induction of cyclin D1 expression in INS-1 beta-cells: involvement of cAMP-responsive element.

Kim, M-J,Kang, J-H,Park, Y G,Ryu, G R,Ko, S H,Jeong, I-K,Koh, K-H,Rhie, D-J,Yoon, S H,Hahn, S J,Kim, M-S,Jo, Y-H Journal of Endocrinology, Ltd. [etc.] 2006 The Journal of endocrinology Vol.188 No.3

<P>Glucagon-like peptide-1 (GLP-1) and its analog exendin-4 (EX) have been considered as a growth factor implicated in pancreatic islet mass increase and beta-cell proliferation. This study aimed to investigate the effect of EX on cyclin D1 expression, a key regulator of the cell cycle, in the pancreatic beta-cell line INS-1. We demonstrated that EX significantly increased cyclin D1 mRNA and subsequently its protein levels. Although EX induced phosphorylation of Raf-1 and extracellular-signal-regulated kinase (ERK), both PD98059 and exogenous ERK1 had no effect on the cyclin D1 induction by EX. Instead, the cAMP-elevating agent forskolin induced cyclin D1 expression remarkably and this response was inhibited by pretreatment with H-89, a protein kinase A (PKA) inhibitor. Promoter analyses revealed that the cAMP-responsive element (CRE) site (at position -48; 5'-TAACGTCA-3') of cyclin D1 gene was required for both basal and EX-induced activation of the cyclin D1 promoter, which was confirmed by site-directed mutagenesis study. For EX to activate the cyclin D1 promoter effectively, CRE-binding protein (CREB) should be phosphorylated and bound to the putative CRE site, according to the results of electrophoretic mobility shift and chromatin immunoprecipitation assays. Lastly, a transfection assay employing constitutively active or dominant-negative CREB expression plasmids clearly demonstrated that CREB was largely involved in both basal and EX-induced cyclin D1 promoter activities. Taken together, EX-induced cyclin D1 expression is largely dependent on the cAMP/PKA signaling pathway, and EX increases the level of phosphorylated CREB and more potently trans-activates cyclin D1 gene through binding of the CREB to the putative CRE site, implicating a potential mechanism underlying beta-cell proliferation by EX.</P>

Potential roles of D-serine and serine racemase in experimental temporal lobe epilepsy

Ryu, H.J.,Kim, J.-E.,Yeo, S.-I.,Kim, D.-S.,Kwon, O.-S.,Choi, S.Y.,Kang, T.-C. Wiley Subscription Services, Inc., A Wiley Company 2010 Journal of neuroscience research Vol.88 No.11

<P>To confirm the roles of D-serinergic gliotransmission in epilepsy, we investigated the relationship between spatiotemporally specific glial responses and the D-serine/serine racemase system in mesial temporal structures following status epilepticus (SE). In control animals, D-serine and serine racemase immunoreactivities were detected mainly in astrocytes. After SE, D-serine and serine racemase immunoreactivities were increased in astrocytes. Double-immunofluorescence study revealed that up-regulation of serine racemase immunoreactivity was relevant not to D-serine immunoreactivity but to nestin or vimentin immunoreactivity. Neither D-serine nor serine racemase was found in naïve or reactive microglia. In addition, phosphorylated N-methyl-D-aspartate (NMDA) receptor subunit 1 (pNR1-Ser896) immunoreactivity in the hippocampus was increased compared with controls. Increased D-serine immunoreactivity showed direct correlation with the phosphorylation of Ser896 of NR1. Given the findings of our previous study, these findings suggest that D-serine and serine racemase in astrocytes may play roles in neuronal hyperexcitability via a cooperative activation of NMDA receptors. Furthermore, serine racemase may be involved in migration and differentiation of immature astrocytes, which is relevant to reactive astrogliosis. © 2010 Wiley-Liss, Inc.</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.

J-PLUS: Identification of low-metallicity stars with artificial neural networks using SPHINX

Whitten, D. D.,Placco, V. M.,Beers, T. C.,Chies-Santos, A. L.,Bonatto, C.,Varela, J.,Cristó,bal-Hornillos, D.,Ederoclite, A.,Masseron, T.,Lee, Y. S.,Akras, S.,Borges Fernandes, M.,Caballero, J. Springer-Verlag 2019 Astronomy and astrophysics Vol.622 No.-

<P><I>Context.</I> We present a new methodology for the estimation of stellar atmospheric parameters from narrow- and intermediate-band photometry of the Javalambre Photometric Local Universe Survey (J-PLUS), and propose a method for target pre-selection of low-metallicity stars for follow-up spectroscopic studies. Photometric metallicity estimates for stars in the globular cluster M15 are determined using this method.</P><P><I>Aims.</I> By development of a neural-network-based photometry pipeline, we aim to produce estimates of effective temperature, <I>T</I>eff, and metallicity, [Fe/H], for a large subset of stars in the J-PLUS footprint.</P><P><I>Methods.</I> The Stellar Photometric Index Network Explorer, SPHINX, was developed to produce estimates of <I>T</I>eff and [Fe/H], after training on a combination of J-PLUS photometric inputs and synthetic magnitudes computed for medium-resolution (<I>R</I> ~ 2000) spectra of the Sloan Digital Sky Survey. This methodology was applied to J-PLUS photometry of the globular cluster M15.</P><P><I>Results.</I> Effective temperature estimates made with J-PLUS Early Data Release photometry exhibit low scatter, σ(<I>T</I>eff) = 91 K, over the temperature range 4500 < <I>T</I>eff (K) < 8500. For stars from the J-PLUS First Data Release with 4500 < <I>T</I>eff (K) < 6200, 85 ± 3% of stars known to have [Fe/H] < −2.0 are recovered by SPHINX. A mean metallicity of [Fe/H] = − 2.32 ± 0.01, with a residual spread of 0.3 dex, is determined for M15 using J-PLUS photometry of 664 likely cluster members.</P><P><I>Conclusions.</I> We confirm the performance of SPHINX within the ranges specified, and verify its utility as a stand-alone tool for photometric estimation of effective temperature and metallicity, and for pre-selection of metal-poor spectroscopic targets.</P>