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61.
Yusuke Kawashima Mamoru Satoh Tatsuya Saito Takashi Matsui Fumio Nomura Hiroyuki Matsumoto Yoshio Kodera 《Biomedical chromatography : BMC》2013,27(6):691-694
We report a cyclic sample pooling technique devised in two‐dimensional liquid chromatography–electrospray ionization mass spectrometry (LC‐ESI‐MS) shotgun proteomics that renders deeper proteome coverage; we combined low pH reversed‐phase (RP) LC in trifluoroacetic acid in the first dimension, followed by cyclic sample pooling of the eluate and low‐pH RP‐LC in formic acid in the second dimension. The new protocol has a significantly higher resolving power suitable for LC‐ESI‐MS/MS shotgun proteomics. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
62.
63.
Dr. Yusaku Nomura Dr. Frédéric Thuaud Dr. Daisuke Sekine Prof. Dr. Akihiro Ito Satoko Maeda Dr. Hiroyuki Koshino Dr. Daisuke Hashizume Dr. Atsuya Muranaka Dr. Thomas Cruchter Prof. Dr. Masanobu Uchiyama Prof. Dr. Satoshi Ichikawa Prof. Dr. Akira Matsuda Prof. Dr. Minoru Yoshida Prof. Dr. Go Hirai Prof. Dr. Mikiko Sodeoka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(35):8387-8392
A synthetic methodology to access all possible stereoisomers of spectomycin A1 (SMA1) and A2 (SMA2) has been established through late-stage diversification. The key reaction for the construction of all four diastereomers is an intramolecular cyclization based on the umpolung of π-allyl palladium species with bis(pinacolato)diborane (B2(pin)2). Silyl group assisted direct benzylic oxidation of each isomer enabled construction of the fragile β-hydroxytetralone skeleton to provide the SMAs. The relative and absolute stereochemistry of SMA2 was also determined, and the absolute stereochemistry of SMA1 was extrapolated based on the optical rotation of SMA2. The axial chirality of SMAs is discussed based on circular dichroism spectra and DFT calculations, and it is concluded that the M isomer is predominant in solution. Biochemical assessment of all isomers in vitro revealed that the C9 hydroxyl group and dimeric structure were both important for protein SUMOylation-inhibitory activity. 相似文献
64.
Optical Review - Increasing efficiency and productivity in the field of agriculture is important to provide sufficient food to the world’s increasing population. It is important to monitor... 相似文献
65.
Abstract Some dicarhoxyphenylphosphonic acids (DCPPA) were prepared by new process. We succeeded in introducing two carhoxyl groups into the phenyl group of phenylphosphonic acid. The dialkyl iso- and tere-phthalate (DACB) were conveniently hrominated with NBS /H2SO4 system to provide the corresponding hromidcs (DACBB) in good yields and good selectivities. 相似文献
66.
Novel aryl-β-C-glucosidation method using glucal boronate was developed. This protocol can offer several advantages including use of non-toxic, easily handling glucal boronate as a crystalline solid and storable at room temperature for several months. Tri-O-methylnorbergenin (8,10-di-O-methylbergenin), an anti-HIV active bergenin derivative, was concisely synthesized by application of the aryl-β-C-glucosidation method. 相似文献
67.
Hiroshi Nomura 《Optical Review》2010,17(5):499-506
A lithographic test pattern, the phase shift grating (PSG) z monitor, is introduced. Through the use of phase shift techniques, position errors of images in the z-direction translate into lateral shifts in the printed pattern. The lateral shifts are easily measurable using an overlay
metrology tool. Each z monitor pattern in a test mask can be directly read for the sign and magnitude of the z error. When the experimental conditions, namely, the period of a PSG and a coherent factor of the lithography tool simultaneously
satisfies a criterion of the asymmetric two-beam interference between the zeroth-order ray and either of the two first-order
rays of diffraction, the linearity of a z-vs-overlay curve is always complete and the slope of the curve is constant everywhere in the image field. Using state-of-the-art
overlay metrology tools, we realized subnanometer-order accuracy in the z measurement. 相似文献
68.
The wave-splitting phase-shifting digital holography using a pixelated microretarder array is proposed. By using four intensity
images recorded by the pixelated microretarder array, Stokes parameters of the incident wave can be calculated. The fully
complex amplitude distribution of the object wave can be obtained by using Stokes parameters, if the polarization states of
the object and reference waves are linear and orthogonal. Two sets of experimental results are provided to verify the feasibility
of the proposed method. One is the result for a movie recording using a CW laser and the other is the result for instant recording
using a single pulsed laser. 相似文献
69.
K. Hirose M. Ejima T. Fujibayashi Y. Fujii K. Futatsukawa O. Hashimoto T. Ishikawa S. Kameoka H. Kanda F. Kato S. Kinoshita T. Kinoshita T. Kon O. Konno K. Maeda A. Matsumura Y. Miura F. Miyahara H. Miyase T. Nakabayashi S.N. Nakamura H. Nomura K. Nonaka A. Ohtani Y. Okayasu M. Oyamada A. Sasaki H. Shimizu T. Takahashi T. Tamae H. Tamura T. Terasawa H. Tsubota K. Tsukada D. Uchida M. Ukai M. Wakamatsu T. Watanabe H. Yamauchi H. Yamazaki K. Yawata 《Physics letters. [Part B]》2009
70.
We developed an ultra-sensitive method of amino acid analysis (AAA) for the absolute quantification of less than 100 ng of proteins, in solution or on polyvinylidene difluoride (PVDF) membranes using an oxygen-free chamber for protein hydrolysis. We used a pre-label method with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate for fluorescence detection, ion-pair chromatography with a reversed-phase column, and an ultra-high-pressure high-performance liquid chromatography. We optimized both handling- and instrument-dependent factors for accurate quantification and showed that the least amount of proteins to quantify was determined by handling accuracy rather than instrumental limit for quantification which was 0.6 fmol/amino acid. As a new evaluation method for the handling accuracy, we adopted the protein identification by the obtained amino acid compositions by AAA and the Swiss-Prot database search without the restriction of species. As a result, the least amount of starting material for AAA was 16 ng (0.24 pmol) for a solution of bovine serum albumin (BSA), 33 ng (0.50 pmol) for BSA on a PVDF membrane, and 44 ng (0.15 pmol) for thyroglobulin on a PVDF membrane. These results demonstrate that the ultra-sensitive AAA developed in this study is feasible for absolute quantification of biological significant protein. Figure
Specification of ultra-sensitive amino acid analysis 相似文献