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81.
Small peptides with less than 1000 in molecular weight are not considered amenable to sandwich immunoassays due to their difficulty of simultaneous recognition by two antibodies. As an alternative, we attempted noncompetitive detection of small peptides by open sandwich enzyme-linked immunosorbent assay (OS-ELISA) utilizing the antigen-induced enhancement of antibody VH/VL interaction. Taking fragments of human osteocalcin (BGP), a major non-collagen peptide produced in bone, as model peptides, OS immunoassay was performed using the cloned VH and VL cDNAs from two anti-BGP monoclonal antibodies either recognizing the N- or C-terminal fragment, respectively. When the clones were used for OS-ELISA with immobilized VL fragment and phage-displayed VH fragment, enhanced VH/VL interaction upon BGP addition was observed. Especially the clone for the C-terminal fragment showed a superior detection limit as well as a wider working range than those of competitive assay. The result was reproduced with purified VH-alkaline phosphatase and MBP-VL fusion proteins, where the latter was directly immobilized onto the microplate wells. The minimum detectable fragment was the hexamer including the C-terminus. This simple approach with a single monoclonal antibody with a short measurement time may prove a useful tool in immunodiagnostics as well as in proteomics research. 相似文献
82.
Abe K Miyoshi K Muto T Ruspita I Horiguchi T Nagata T Noma T 《Journal of Bioscience and Bioengineering》2007,103(5):479-485
Teeth are the hardest tissues covered with enamel produced by ameloblasts. The ameloblast differentiation is controlled by sequential epithelial-mesenchymal interactions during tooth morphogenesis. However, the molecular mechanism of ameloblast differentiation remains unclear. To address this question, we developed an in vitro assay system to evaluate the molecular mechanism of amelogenesis. First, we established dental epithelium-derived clones from 6-day-old rat incisors and established that cells of the clone SRE-G5 were the largest producers of amelogenin mRNA. Next, we analyzed the effects of several chemicals on the amelogenin expression in SRE-G5 cells. Only mitogen-activated protein kinase (MAPK) activators enhanced amelogenin mRNA expression. This finding corresponded to the immunohistochemical data showing the presence of phosphorylated forms of p38, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK) during ameloblast differentiation. To examine the roles of MAPK signals, we compared the effects of anisomycin and sodium salicylate on the expression of tooth-related differentiation markers. Both anisomycin and sodium salicylate induced amelogenin, Abcg2, and Bmp4 mRNA and down-regulated p75NGFR mRNA. On the other hand, ALP, ectodin, Bmp2 and Fgf8 mRNA were up-regulated only by anisomycin. These results indicate that MAPK signaling functions, at least in part, as the inducer of ameloblast differentiation. 相似文献
83.
Yasunori Mizuno Hideki Muramatsu Takamitsu Aoki Taro Sometani 《Electrical Engineering in Japan》2000,130(4):26-34
A plasma horizontal position feedback control system (PHPFCS) and a digital current drive (DCD) for controlling vertical magnetic field are made on an experimental base, and the horizontal position of a plasma in a small tokamak (HAMANA‐T) is controlled by PID operations from the initial phase of plasma generation. The DCD consists of constant‐current discharge units for multiple condensers and drives a digital current analogous as a whole to the control signal of PHPFCS in the range of ±90 A. The maximum value of the digital current increases in proportion to the number of units. This PHPFCS elongates plasma duration from 1.3 ms to 2.1 ms, smooths the waveform of plasma current, and reduces the plasma loop voltage from 25 V to 20 V. Furthermore, PHPFCS reduces the range of variation in plasma horizontal displacement from 3.5 cm to within 0.5 cm and makes it possible to set accurately the horizontal position from the initial phase in the inner region of a vacuum chamber. © 2000 Scripta Technica, Electr Eng Jpn, 130(4): 26–34, 2000 相似文献
84.
85.
The influence of tungstate on the oxidation of green rust [GR(Cl–)], which contains both Fe(II) and Fe(III), was investigated by synthesizing suspensions of GR(Cl–) containing tungstate and oxidizing them via injection of N2 gas containing O2. XRD and TEM analyses were used for characterizing the solid particles formed during synthesis and oxidation. The results showed that the formation of fine α‐FeOOH was enhanced by the addition of tungstate to the GR(Cl–) suspensions, while GR(Cl–) without tungstate was transformed primarily into γ‐FeOOH. The pH, oxidation‐reduction potential (ORP), and dissolved oxygen (DO) values of the aqueous solution were measured during oxidation of GR(Cl–) with and without tungstate. The results showed that whereas the pH value of the solution was decreased and the ORP value was increased monotonically by oxidation of GR(Cl–), the pH and ORP values during oxidation the GR(Cl–) suspension containing tungstate revealed characteristic changes with time. XAS was also used for characterizing the chemical state and local structure of tungstate in the oxidized particles. The results indicated that the local structure of WO was essentially retained in the particles precipitated from GR(Cl–) suspensions. 相似文献
86.
Ando T Matsumoto N Ohtake Y Takiguchi Y Inoue T 《Journal of the Optical Society of America. A, Optics, image science, and vision》2010,27(12):2602-2612
We investigate optical singularities in coaxial superpositions of two Laguerre-Gaussian (LG) modes with a common beam waist from the viewpoints of a general formulation of phase structure, experimental generation of various superposition beams, and evaluation of the generated beams' fidelity. By applying a holographic phase-amplitude modulation scheme using a phase-modulation-type spatial light modulator, output fidelity beyond 0.960 was observed under several typical conditions. Additionally, an elliptic-type folded singularity, which provides a different class of phase structures from familiar helical singularities, was predicted and observed in a superposition involving two LG modes of both radially and azimuthally higher orders. 相似文献
87.
Hideyo Takatsuki Kevin M. Rice Shinichi Asano B. Scott Day Mizuki Hino Kazuhiro Oiwa Ryoki Ishikawa Yuichi Hiratsuka Taro Q. P. Uyeda Kazuhiro Kohama Eric R. Blough 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(3):452-457
The utilization of motor proteins for the movement and assembly of synthetic components is currently a goal of nanoengineering research. Application of the myosin actin motor system for nanotechnological uses has been hampered due to the low flexural rigidity of individual F‐actin filaments. Here it is demonstrated how actin bundling can be used to affect the translational behavior of myosin‐propelled filaments, transport molecules across a motor‐patterned surface, and that the movement of bundled actin can be regulated photonically. These data suggest that actin bundling may significantly improve the applicability of the myosin motor for future nanotechnological applications. 相似文献
88.
The oxidation of hydrosulphate green rust (GR2(SO42−)) suspension containing different chromium ion species was investigated by X-ray diffraction, X-ray absorption spectroscopy and transmission electron microscopy. The pH, oxidation-reduction potential and amount of dissolved oxygen in aqueous solutions were measured during the reactions. The results show that the addition of Cr(III)2(SO4)3 solution suppresses the transformation of GR2(SO42−) into iron oxyhydroxides and oxides in aqueous solution, while the addition of Na2Cr(VI)O4 solution promotes the transformation of GR2(SO42−) in which Cr(VI) is reduced to Cr(III); α-FeOOH particles were refined by the addition of the chromium ions. 相似文献
89.
Naoomi Yamada Taro Hitosugi Ngoc Lam Huong Hoang Shoichiro Nakao Yasushi Hirose Toshihiro Shimada Tetsuya Hasegawa 《Thin solid films》2010,518(11):3101-3104
Transparent conducting Nb-doped anatase TiO2 (TNO) epitaxial films were sputtered from TiO2-, Ti2O3-, and Ti-based targets at various oxygen partial pressures (Po2). Using the TiO2- and Ti2O3-based targets, highly conductive films showing a resistivity (ρ) of ~ 3 × 10− 4 Ω cm could be formed without postdeposition treatment. In the case of the TNO films formed from the Ti-based target, reductive annealing had to be carried out at a temperature of 600 °C to achieve similar resistivity values. Thus, the use of oxide targets is preferable to obtain as-grown transparent conducting TNO films. In particular, the Ti2O3-based target is practically advantageous, because it offers a wide range of optimal Po2 values at which ρ values of the order of 10− 4 Ω cm are achievable. 相似文献
90.
Antihyperlipidemic effect of Acanthopanax senticosus (Rupr. et Maxim) Harms leaves in high‐fat‐diet fed mice
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