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81.
Minoru Ameyama Toshikazu Chiyonobu Osao Adachi 《Bioscience, biotechnology, and biochemistry》2013,77(8):1535-1536
The active site of α-glucosidase from Mucor javanicus IFO 4570 was investigated by kinetic studies. Competition between maltose and soluble starch, and linearity of Lineweaver-Burk plots for the mixed substrates were observed. The dependence of the apparent maximum velocities agreed with those predicted for a single active site mechanism. These results suggest that the enzyme hydrolyzes maltose and soluble starch at a single active site. 相似文献
82.
Morimasa Yoshioka Kuniyoshi Takatsu Minoru Kawahira Kihachiro Takahashi 《Microbiology and immunology》1967,11(4):311-321
In order to confirm the data reported in the previous papers, variously prepared pertussis vaccines were employed in the present investigation. Pertussis organisms grown either on a solid or in a liquid semisynthetic medium were treated by: (1) heating at 56 C for 30 min, (2) storage in 0.1% formalin at 37 C for 5 days, (3) storage in 0.1% formalin at 25 C for 5 days, and (4) simple addition of sodium ethyl-mercuri thiosalicylate (merthiolate) as a preservative. Freeze-dried vaccines were made from these preparations four and a half months later. Mice were immunized intraperitoneally and challenged intracerebrally with a virulent strain of Bordetella pertussis 10 or 17 days later. The data were analyzed statistically assuming the probit corresponding to the percentage of survivors at any dose be a linear function of the logarithms of the dose. The 50% effective doses (ED50) and slopes of each vaccine were found to be uniform. More accurate estimates of ED50 were obtained by employing a pooled slope in each experiment. From these ED50 values, the relative potency was estimated by comparing the value of a vaccine to that of a dried merthiolate-vaccine. For vaccines derived from solid cultures, with an immunization period of 17 days, the relative potency of the vaccine heated at 56 C was 0.63 (95% fiducial limits=0.52 to 0.76); the value for the formalinized vaccine at 37 C was 0.40 (0.30 to 0.53) and one at 25 C was 0.51 (0.34 to 0.77). Vaccines derived from liquid cultures showed a relative potency of 20 to 50% less than that of corresponding vaccine derived from a solid culture. The potency obtained for the 17 day immunization period was usually higher than that for the 10 day period. Using the overall-pooled slope, an experimental design which will be appropriate for statistical analysis is discussed. 相似文献
83.
Minoru Okuma Tanihiro Yoshimoto Shozo Yamamoto 《Prostaglandins & other lipid mediators》1977,14(5):891-896
The effect of human platelet functions of 9,11-dithio analogues of prostaglandin endoperoxide was investigated. Methyl (5z,9α,11α,13e,15S)-9,11-epidithio-15-hydroxyprosta- 5,13-dienoate induced platelet aggregation, while the 9β,11β-epimer was inactive. The platelet aggregation caused by the 9α,11α-dithio analogue was associated with serotonin release from platelets, and was inhibited by methyl ester of prostaglandin I2 (prostacyclin) but not by indomethacin. 相似文献
84.
Role of salicylic acid glucosyltransferase in balancing growth and defence for optimum plant fitness
85.
da Silva Gessiane Pereira de Melo Josi Teixeira Monteiro Frederico Ozanan Barros Ferreira Ana Karolyna Pereira Carneiro Liliane Almeida Takeshita Rafaela S. C. 《International journal of primatology》2021,42(5):722-736
International Journal of Primatology - The hormone dehydroepiandrosterone (DHEA) and its sulfate ester (DHEAS) are the most abundant circulating steroids in human and some nonhuman primates, and... 相似文献
86.
87.
Chiho Nishizawa Keizo Takeshita Jun-ichi Ueda Michiko Mizuno Kazuo T. Suzuki Toshihiko Ozawa 《Free radical research》2013,47(4):385-392
Photosensitizers newly developed for photodynamic therapy of cancer need to be assessed using accurate methods of measuring reactive oxygen species (ROS). Little is known about the characteristics of the reaction of singlet oxygen (1O2) with spin traps, although this knowledge is necessary in electron spin resonance (ESR)/spin trapping. In the present study, we examined the effect of various reductants usually present in biological samples on the reaction of 1O2 with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). The ESR signal of the hydroxyl radical (?OH) adduct of DMPO (DMPO-OH) resulting from 1O2-dependent generation of ?OH strengthened remarkably in the presence of reduced glutathione (GSH), 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), ascorbic acid, NADPH, etc. A similar increase was observed in the photosensitization of uroporphyrin (UP), rose bengal (RB) or methylene blue (MB). Use of 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide (DEPMPO) as a spin trap significantly lessened the production of its ?OH adduct (DEPMPO-OH) in the presence of the reductants. The addition of DMPO to the DEPMPO-spin trapping system remarkably increased the signal intensity of DEPMPO-OH. DMPO-mediated generation of ?OH was also confirmed utilizing the hydroxylation of salicylic acid (SA). These results suggest that biological reductants enhance the ESR signal of DMPO-OH produced by DMPO-mediated generation of ?OH from 1O2, and that spin trap-mediated ?OH generation hardly occurs with DEPMPO. 相似文献
88.
George G. Glenner Minoru Harada Chaviva Isersky 《Preparative biochemistry & biotechnology》2013,43(1):39-51
Amyloid fibril concentrates have been fractionated and shown to have homogeneous fragments of the variable region of immunoglobulin proteins as their major protein constituent. Amyloid fibril protein purification was performed on ten amyloid preparations by sequential gel filtration on Sepharose 4 B and Sephadex G-100 columns equilibrated with 5 M guanidine-HCl in 1 N acetic acid. 相似文献
89.
Takumi OBARA Satoshi SHUUTO Yasuyoshi SAITO Minoru TORIYA Kiyoshi OGAWA Satoshi YAGINUMA 《Nucleosides, nucleotides & nucleic acids》2013,32(6):1157-1167
Abstract The 6′-carboxylic acid derivative of neplanocin A 3 was synthesized from NPA, and was converted to the corresponding methyl ester 4 and amides 5 and 6. These were evaluated for their anti-RNA-virus activities. Of the derivatives synthesized, only 5 was active against RNA viruses within the concentration range of 0.14-4.88 μg/mL. Compounds 3 and 5 showed a potent inhibitory effect on S-adenosylhomocysteine (AdoHcy) hydrolase from rabbit erythrocytes. Although a close correlation between the inhibitory effect of adenosine analogues on AdoHcy hydrolase and their antiviral potency has been demonstrated, 3 did not show any anti-RNA-virus activities. 相似文献
90.
Kayo Kobayashi Yasuhiro Kamei Masato Kinoshita Thomas Czerny Minoru Tanaka 《Genesis (New York, N.Y. : 2000)》2013,51(1):59-67
We established three lines of transgenic medaka, a heat‐shock element (HSE) monitor line (hse‐GFP line), heat‐inducible driver lines (hse‐cre lines), and effector lines (gapdh‐loxP[DsRed]‐GFP lines). We employed these to comprehensively analyze gene induction at different time points in various tissues. These analyses demonstrate a good response of synthetic HSEs by heat treatment during embryogenesis and the mosaic gene induction by cre/loxP‐mediated recombination, thus providing practical information regarding the feasibility of a heat‐inducible cre/loxP‐mediated system in medaka. We also activated recombination by local heat‐treatment using a metal probe and an infrared laser. Our results collectively indicate that these lines allow us to perform lineage tracing and mosaic analysis and provide the platform to investigate gene functions at later developmental stage and adult. genesis 51:59–67, 2013. © 2012 Wiley Periodicals, Inc. 相似文献