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91.
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
92.
Dr. Takahito Mukai Dr. Markus Englert Dr. H. James Tripp Dr. Corwin Miller Dr. Natalia N. Ivanova Dr. Edward M. Rubin Dr. Nikos C. Kyrpides Prof. Dieter Söll 《Angewandte Chemie (International ed. in English)》2016,55(17):5337-5341
Selenocysteine (Sec or U) is encoded by UGA, a stop codon reassigned by a Sec‐specific elongation factor and a distinctive RNA structure. To discover possible code variations in extant organisms we analyzed 6.4 trillion base pairs of metagenomic sequences and 24 903 microbial genomes for tRNASec species. As expected, UGA is the predominant Sec codon in use. We also found tRNASec species that recognize the stop codons UAG and UAA, and ten sense codons. Selenoprotein synthesis programmed by UAG in Geodermatophilus and Blastococcus, and by the Cys codon UGU in Aeromonas salmonicida was confirmed by metabolic labeling with 75Se or mass spectrometry. Other tRNASec species with different anticodons enabled E. coli to synthesize active formate dehydrogenase H, a selenoenzyme. This illustrates the ease by which the genetic code may evolve new coding schemes, possibly aiding organisms to adapt to changing environments, and show the genetic code is much more flexible than previously thought. 相似文献
93.
Yoshiko Ogata 《Communications in Mathematical Physics》2016,348(3):847-895
We introduce a class of gapped Hamiltonians on quantum spin chains, which allows asymmetric edge ground states. This class is an asymmetric generalization of the class of Hamiltonians (Fannes et al. Commun Math Phys 144:443–490, 1992). It can be characterized by five qualitative physical properties of ground state structures. In this Part I, we introduce the models and investigate their properties. 相似文献
94.
High‐Density Liquid‐Crystalline Polymer Brushes Formed by Surface Segregation and Self‐Assembly
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Koji Mukai Dr. Mitsuo Hara Prof. Shusaku Nagano Prof. Takahiro Seki 《Angewandte Chemie (International ed. in English)》2016,55(45):14028-14032
High‐density polymer brushes on substrates exhibit unique properties and functions stemming from the extended conformations due to the surface constraint. To date, such chain organizations have been mostly attained by synthetic strategies of surface‐initiated living polymerization. We show herein a new method to prepare a high‐density polymer brush architecture using surface segregation and self‐assembly of diblock copolymers containing a side‐chain liquid‐crystalline polymer (SCLCP). The surface segregation is attained from a film of an amorphous base polymer (polystyrene, PS) containing a minor amount of a SCLCP‐PS diblock copolymer upon annealing above the glass‐transition temperature. The polystyrene portion of the diblock copolymer can work as a laterally mobile anchor for the favorable self‐assembly on the polystyrene base film. 相似文献
95.
Tobiishi S Sasada T Nojiri Y Yamamoto F Mukai T Ishiwata K Maeda M 《Chemical & pharmaceutical bulletin》2007,55(8):1213-1217
Methoxy and fluorine analogs substituted on the terminal carbon of the pentyl chain of N-(piperidinyl)-1-(2,4-dichlorophenyl)-4-methyl-5-(4-pentylphenyl)-1H-pyrazole-3-carboxamide (O-1302) were synthesized in a multi-step process from 5-phenyl-1-pentanol, which was based on the 1,5-diarylpyrazole core template of N-(piperidinyl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (SR141716) through condensation of the respective amine with pyrazole carboxylic acid, in order to develop tracers for medical imaging. Their potency for inhibiting the binding of the CB1 antagonist [(3)H]SR141716 was evaluated with the aim of developing positron emission tomography (PET) ligands for the cerebral cannabinoid CB1 receptor. These analogs bearing a piperidinyl carboxamide at the C(3) of the pyrazole ring exhibited affinities comparable to those of the CB1 reference antagonist SR141716, which warrants further investigation using the radiolabeled form for biological imaging studies. A morpholine ring substituted at the C(3) of the pyrazole ring resulted in a reduction of the CB1 affinity. 相似文献
96.
The simple refluxing of allenynes, having a phenylsulfonyl functionality on the allenyl group, in xylene (or mesitylene) without microwave irradiation resulted in the efficient formation of bicyclo[5.2.0]nona-1,7-dienes and bicyclo[4.2.0]octa-1,6-dienes in high yields. This method was shown to be successfully applicable to the first construction of bicyclo[6.2.0]deca-1,8-dienes. Construction of the corresponding oxa- and azabicyclo[m.2.0] frameworks could also be attained. This thermal ring-closing reaction involves the formal [2+2] cycloaddition in which the distal double bond of an allenyl moiety exclusively served as one of the pi-components regardless of the position of the phenysulfonyl functionality on the allenyl moiety. 相似文献
97.
1-(5,6-Dihydro-2H-thiopyran-2-yl)uracil derivatives, a new 4′-thio-D4-nucleoside analogue, were synthesized by reacting 5,6-dihydro-2H-thiopyran sulfoxide and persilylated uracil in a Pummerer-type thioglycosylation reaction. The reaction of 5-alkyl substituted dihydrothiopyran sulfoxide 7 only gave 1-(dihydrothiopyran-2-yl)uracil 9. On the other hand, the reaction with a 5-siloxy substituted derivative of 7 resulted in a mixture of products with the uracil moiety at either the α- or the γ-position. The use of a prolonged reaction time resulted in the exclusive formation of the 4-substituted dihydrothiopyran derivative 10. The result suggests that an equilibrium is operative in the formation of the α- and γ-adducts and that the latter should be more thermodynamically stable than the former. This conclusion was also supported by theoretical calculations. 相似文献
98.
Tanaka H Takino M Sugita-Konishi Y Tanaka T 《Rapid communications in mass spectrometry : RCM》2006,20(9):1422-1428
A liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (LC/APCI-MS) method based on time-of-flight MS (TOFMS) with a real-time reference mass correction technique was developed for the simultaneous determination of Fusarium mycotoxins (nivalenol, deoxynivalenol, fusarenon X, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, HT-2 toxin, T-2 toxin, diacetoxyscirpenol, zearalenone) and Aspergillus mycotoxins (aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2) in corn, wheat, cornflakes and biscuits. Samples were cleaned up with a MultiSep #226 column. Detection of the mycotoxins was carried out in exact mass chromatograms with a mass window of 0.03 Th. Calibration curves were linear from 2 to 200 ng x mL(-1) for trichothecenes and zearalenone, and 0.2 to 20 ng x mL(-1) for aflatoxins, by 20 microL injection. The limits of detection ranged from 0.1 to 6.1 ng x g(-1) in foodstuffs analyzed in this study. The LC/TOFMS method was found to be suitable for the screening of multiple mycotoxins in foodstuffs rapidly and with high sensitivity, and its performance was demonstrated for the confirmation for target mycotoxins. 相似文献
99.
Yoshiko Ogata 《Communications in Mathematical Physics》2010,296(1):35-68
We show the full large deviation principle for KMS-states and C*-finitely correlated states on a quantum spin chain. We cover general local observables. Our main tool is Ruelle’s transfer
operator method. 相似文献
100.
5-O-(4-[125 I]Iodobenzyl)-L-ascorbic acid: electrophilic radioiodination and biodistribution in mice
Kim J Kino T Kato H Yamamoto F Sano K Mukai T Maeda M 《Chemical & pharmaceutical bulletin》2012,60(2):235-240
As a part of our efforts to develop potential imaging agents for ascorbate bioactivity, 5-O-(4-[(125)I]iodobenzyl)-L-ascorbic acid ([(125)I]1) was prepared through a two-step sequence which involved radioiodo-destannylation of a protected tributylstannyl precursor 6, followed by hydrolysis in acidic methanol of the protecting groups in 61% overall radiochemical yield, with a radiochemical purity of over 98% and a specific activity of more than 15.4?GBq/μmol. Tissue distribution of [(125)I]1 in tumor-bearing mice showed signs of distribution profiles similar to the reported results for 6-deoxy-6-[(18)F]fluoro-L-ascorbic (6-(18)FAsA) acid and 6-deoxy-6-[(131)I]iodo-L-ascorbic acid (6-(131)IAsA) but with notable differences in the adrenal glands, in which considerably lower uptake of radioactivity and rapid clearance with time were observed. Pretreatment of mice with a known inhibitor of ascorbate transport, sulfinpyrazone, did not produce any significant change in the adrenal uptake of radioactivity after injection of [(125)I]1 compared to the control, suggesting that uptake in the adrenal glands is independent of the sodium-dependent vitamin C transporter 2 transport mechanism. Introduction of a bulky substituent at C-5 on AsA, such as an iodobenzyloxy group, may not be suitable for the design of analogs that may still be able to maintain characteristic distribution properties in vivo seen with AsA itself. 相似文献