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201.
To electrochemically sense lymphoma cells (U937), we fabricated a multifunctional peptide probe that consists of cell-penetrating/apoptosis-inducing/electron-transfer peptides. Electron-transfer peptides derive from cysteine residue combined with the C-terminals of four tyrosine residues (Y4). A peptide whereby Y4C is bound to the C-terminals of protegrin 1 (RGGRLCYCRRRFCVCVGR-NH2) is known to be an apoptosis-inducing agent against U937 cells, and is referred to as a peptide-1 probe. An oxidation response of the peptide-1 probe has been observed due to a phenolic hydroxyl group, and this response is decreased by the uptake of the peptide probe into the cells. To improve the cell membrane permeability against U937 cells, the RGGR at the N-terminals of the peptide-1 probe was replaced by RRRR (peptide-2 probe). In contrast, RNRCKGTDVQAWY4C (peptide-3 probe), which recognizes ovalbumin, was constructed as a control. Compared with the other probes, the change in the peak current of the peptide-2 probe was the greatest at low concentrations and occurred in a short amount of time. Therefore, the cell membrane permeability of the peptide-2 probe was increased based on the arginine residues and the apoptosis-inducing peptides. The peak current was linear and ranged from 100 to 1000 cells/ml. The relative standard deviation of 600 cells/ml was 5.0% (n = 5). Furthermore, the membrane permeability of the peptide probes was confirmed using fluorescent dye. 相似文献
202.
ABSTRACTWe consider a certain family of CIFSs of the generalized complex continued fractions with a complex parameter space. We show that for each CIFS of the family, the Hausdorff measure of the limit set of the CIFS with respect to the Hausdorff dimension is zero and the packing measure of the limit set of the CIFS with respect to the Hausdorff dimension is positive (main result). This is a new phenomenon of infinite CIFSs which cannot hold in finite CIFSs. We prove the main result by showing some estimates for the unique conformal measure of each CIFS of the family and by using some geometric observations. 相似文献
203.
Hiroki Dobashi Dr. Lorenzo Catti Dr. Yuya Tanaka Prof. Dr. Munetaka Akita Prof. Dr. Michito Yoshizawa 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(29):11979-11983
To gain insight into the host functions of a nanocavity encircled by both polyaromatic panels and heteroatoms, nitrogen-doped polyaromatic capsules were successfully synthesized from metal ions and pyridine-embedded, bent anthracene-based ligands. The new capsules display unique host–guest interactions in the isolated cavities, which are distinct from those of the undoped analogues. Besides the inclusion of Ag+ ions, the large absorption change of fullerene C60 and altered emission of a BODIPY dimer are observed upon encapsulation by the present hosts. Moreover, the N-doped capsule exhibits specific binding ability toward progesterone and methyltestosterone, known as a natural female and synthetic male hormone, respectively, in water. 相似文献
204.
A biphenyl-based amino sulfonamide was designed to improve the intrinsic low catalytic activity of amine organocatalysts. The newly synthesized amino sulfonamide catalyst promoted the Mannich reaction in a highly enantioselective fashion and a remarkable catalyst turnover number was achieved. 相似文献
205.
Dr. Norifumi Kawakami Hiroki Kondo Yuki Matsuzawa Kaoru Hayasaka Erika Nasu Kenji Sasahara Dr. Ryoichi Arai Prof. Kenji Miyamoto 《Angewandte Chemie (International ed. in English)》2018,57(38):12400-12404
Protein‐based nanoparticles hold promise for a broad range of applications. Here, we report the production of a uniform anionic hollow protein nanoparticle, designated TIP60, which spontaneously assembles from a designed fusion protein subunit based on the geometric features of polyhedra. We show that TIP60 tolerates mutation and both its interior and exterior surfaces can be chemically modified. Moreover, TIP60 forms larger structures upon the addition of a cationic protein. Therefore, TIP60 can be used as a modifiable nano‐building block for further molecular assembly. 相似文献
206.
Ruthenium(0)‐Catalyzed Cycloaddition of 1,2‐Diols,Ketols, or Diones via Alcohol‐Mediated Hydrogen Transfer
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Hiroki Sato Dr. Ben W. H. Turnbull Dr. Keisuke Fukaya Prof. Michael J. Krische 《Angewandte Chemie (International ed. in English)》2018,57(12):3012-3021
Merging the characteristics of transfer hydrogenation and carbonyl addition, a broad new class of ruthenium(0)‐catalyzed cycloadditions has been developed. As discussed in this Minireview, fused or bridged bicyclic ring systems are accessible in a redox‐independent manner in C?C bond‐forming hydrogen transfer reactions of diols, α‐ketols, or 1,2‐diones with diverse unsaturated reactants. 相似文献
207.
Second generation polyphenol dendrimers (PDs) with different core molecules were synthesized, and their chemiluminescence (CL) was measured by reacting the PDs with H2O2 under alkaline conditions. All of the PDs showed a strong CL, more than 120-fold greater than that of gallic acid. Various CL intensities of the PDs were obtained using different core molecules in the PDs. The distance between each dendron in the PD structure is crucial in the PD CL intensity. 相似文献
208.
Aratono M Mori A Koga I Shigehisa M Onimaru N Tsuchiya K Takiue T Matsubara H 《The journal of physical chemistry. B》2008,112(39):12304-12311
Aggregate formation of a didodecyldimethylammonium bromide (DDAB) and didodecyldimethylammonium chloride (DDAC) mixture in aqueous solution was investigated. The concentration vs composition diagram of aggregate formation was constructed by analyzing the surface tension, turbidity, and electrical conductivity data. The cryogenic transmission electron microscopy was applied to several representative points in the diagram and provided information of the morphology of aggregates. The sequence of monomer (m) - m + small aggregate (A) - m + A + vesicle (V) - m + V was concluded with increasing total concentration of surfactants at all mixing ratios. The compositions of counterions in A and V were estimated on the basis of thermodynamic consideration and examined from the viewpoint of asymmetry of constituents and uneven distribution between outer and inner monolayers of a vesicle bilayer. Vesicle surfaces were suggested to abound in chloride ions compared to bulk solution, which is opposite to spherical micelle surfaces. 相似文献
209.
Soga S Shirai H Kobori M Hirayama N 《Journal of chemical information and modeling》2008,48(8):1679-1685
The idea that there should be a specific site on a protein for a particular functional small molecule is widespread. It is, however, usually not so easy to understand what characteristics of the site determine the binding ability of the functional small molecule. We have focused on the concurrence rate of the 20 standard amino acids at such binding sites. In order to correlate the concurrence rate and the specific binding site, we have analyzed high-quality X-ray structures of complexes between proteins and small molecules. A novel index characterizing the binding site based on the concurrency rate has been introduced. Using this index we have identified that there is a specific concavity designated as a chemocavity where a specific group of small molecules, i.e., canonical molecular group, is highly inclined to be bound. This study has demonstrated that a chemocavity is reserved for a specific canonical molecular group, and the prevalent idea has been confirmed. 相似文献
210.
Nantaporn Haskins Maria Panglao Qiuhao Qu Himani Majumdar Juan Cabrera-Luque Hiroki Morizono Mendel Tuchman Ljubica Caldovic 《BMC biochemistry》2008,9(1):24