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121.
Daisuke Asai Tadashi Fukuda Kazunori Morokuma Daiki Funamoto Yuko Yamaguchi Takeshi Mori Yoshiki Katayama Keigo Shibayama Hideki Nakashima 《Macromolecular bioscience》2019,19(10)
Vaccines typically contain an antigen, delivery system (vehicle), and adjuvant, all of which contribute to inducing a potent immune response. Consequently, design of new vaccines is difficult, because the contributions and interactions of these components are difficult to distinguish. Here, it is aimed to develop an easy‐to‐use, non‐immunogenic, injectable depot system for sustained antigen release that will be suitable for assessing the efficacy of prolonged antigen exposure per se for inducing an immune response. This should mimic real‐life infections. Recombinant elastin‐like polypeptides with periodic cysteine residues (cELPs) are selected, which reportedly show little or no immunogenicity, as carriers and tetanus toxoid (Ttd) as an antigen. After subcutaneous injection of the mixture, cELP rapidly forms a disulfide cross‐linked hydrogel in situ, within which Ttd is physically incorporated, affording a biodegradable antigen depot. A series of Ttd‐containing hydrogels is examined. A single injection induces high levels of tetanus antibody with high avidity for at least 20 weeks in mice. The chain length of cELP proves critical, whereas differences in hydrophobicity has little effect, although hydrophilic cELPs are more rapidly biodegraded. This system's ability to distinguish the contribution of sustained antigen release to antibody induction should be helpful for rational design of next‐generation vaccines. 相似文献
122.
Low temperature growth of silicon epitaxial layers has been performed by two methods: by molecular beam epitaxy and by solid-phase crystallization of amorphous films deposited onto crystalline substrates under ultra-high vacuum. 相似文献
123.
Noboru Tohge Atsunori Matsuda Tsutomu Minami Yoshihiro Matsuno Shinya Katayama Yoshirou Ikeda 《Journal of Non》1988,100(1-3):501-505
A novel process has been developed to form fine patterns on glass substrates. The process consists of the following steps: (1) coating of gel film on a substrate, (2) patterning on the gel film, and (3) heat-treatment. The key point in this process is the control of hardening of the gel films by the addition of organic polymers such as polyethylene glycol (PEG). The addition of PEG increased the viscosity of the coating solutions and delayed the gelation time, but had little effect on the optical properties of the resultant heat-treated glass films. The newly developed process is expected to be applicable to the formation of the optical devices such as diffraction gratings and pre-groovesof optical memory disks. 相似文献
124.
The picolinoxy group was found to be an extremely powerful leaving group for allylic substitution with aryl nucleophiles derived from ArMgBr and CuBr*Me2S. The substitution proceeds with anti SN2' pathway and with high chirality transfer. The electron-withdrawing effect of the pyridyl group and chelation to MgBr2 are likely the origin of success. Results suggesting these effects were obtained. 相似文献
125.
Kang JH Kuramoto M Tsuchiya A Toita R Asai D Sato YT Mori T Niidome T Katayama Y 《European journal of mass spectrometry (Chichester, England)》2008,14(4):261-265
To identify the correlation between the phosphorylation ratios by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-ToF MS) analysis and enzyme kinetics (K(m), V(max), and V(max)/K(m)) is important to understand whether MALDI-TOF MS can be applied for monitoring the properties of peptides that are substrates of protein kinases. The correlation between phosphorylation ratios and enzyme kinetics was examined using peptides for protein kinase C (PKC) and for 60 kDa phosphoprotein, encoded by the cellular sarcoma gene (c-Src). Phosphorylation ratios, analyzed by MALDI-ToF MS, showed higher correlation coefficient (r = > +0.7) for V(max)/K(m) compared with that (r = < -/+0.6) for K(m) or V(max). For ion modes, a higher correlation coefficient between phosphorylation ratios and V(max)/K(m) was identified in the positive mode (r = > +0.7) compared to that in the negative mode (r = < +0.5). These results suggest that MALDI-ToF MS is a useful tool to evaluate V(max)/K(m) of peptides for protein kinases. 相似文献
126.
Azido-protected Fmoc-Lys-OH (Fmoc-Lys(N3)-OH) was synthesized from Fmoc-Lys-OH by the copper(II)-catalyzed diazo transfer method, and introduced to a peptide by the ordinary Fmoc-based solid-phase peptide synthesis. This azido peptide could be condensed with a peptide thioester by the Ag+-free thioester method without any significant side reactions. The azido group was easily reduced to an amino group by Zn powder after peptide condensation. 相似文献
127.
The recently developed near-field heterodyne transient grating method was utilized in the analysis of photochemical reaction dynamics. It was applied to the dynamics measurement of the dimerization reaction of anthracene in the temporal range from nanoseconds to milliseconds. By means of wide dynamic range measurements, the relaxation processes of excited states such as the excimer and triplet, and the diffusion process of the photodimer product, could be directly observed. Relative photodimerization efficiency obtained experimentally was compared with the simulation results of the reaction kinetics on the basis of two different reaction schemesreaction by way of the singlet or triplet excited statesand it was confirmed that this reaction occurs through the singlet excited state. 相似文献
128.
Kang JH Asai D Kim JH Mori T Toita R Tomiyama T Asami Y Oishi J Sato YT Niidome T Jun B Nakashima H Katayama Y 《Journal of the American Chemical Society》2008,130(45):14906-14907
We succeeded in cancer cell specific gene expression by using a polyplex responsive to protein kinase Calpha, which is activated in various types of cancer cells. 相似文献
129.
Ishizaka T Okada S Tokuyama E Mukai J Uchida T 《Chemical & pharmaceutical bulletin》2008,56(10):1389-1394
The objective of the study was to evaluate the bitterness, grittiness and uniformity of drug loading as measures of the quality of 12 formulations of clarithromycin dry syrup (CAMDS), comprising one branded and 11 generic products. Some of the generic CAMDS formulations were more bitter than the branded product while others had similar bitterness when tested as aqueous suspensions. Only one generic product was less bitter than the branded product when tested as a suspension in acidic sports drink. The usual dissolution test described in JP XV could not be used to evaluate the bitterness of the products. A brief dissolution test using only 12.5 ml of water was used to evaluate the bitterness of the products in aqueous suspensions. There were considerable variances in the grittiness of the various products, which were independent of particle size. Changes in grittiness level seemed to be correlated with changes in the intensity of bitterness due to the disintegration of the formulation. Finally, there was less variation in the uniformity of drug loading for the branded product than for the generic products. These data may be useful when selecting which CAMDS formulation to prescribe. 相似文献
130.
Ion‐Free and Ion‐Pairing Assemblies of Anion‐Responsive π‐Electronic Systems Possessing Directly Linked Alkyl Chains 下载免费PDF全文
Dr. Yohei Haketa Daisuke Katayama Shinya Fukunaga Dr. Yuya Bando Dr. Tsuneaki Sakurai Dr. Wakana Matsuda Prof. Shu Seki Prof. Hiromitsu Maeda 《化学:亚洲杂志》2016,11(14):2025-2029
Alkyl‐substituted pyrrole‐based anion‐responsive π‐electronic systems formed supramolecular gels and liquid crystals through effective π–π stacking and van der Waals interactions. The addition of chloride as a planar cation salt afforded ion‐pairing assemblies as soft materials comprising planar receptor‐Cl? complexes and the cation. 相似文献