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51.
Highlights? β-catenin nuclear asymmetry after animal-vegetal-oriented cell divisions ? β-catenin nuclear asymmetry drives binary cell fate choices ? Combinatorial codes of nuclear β-catenin activation segregate ascidian germ layers ? Nuclear β-catenin ON-to-OFF activity is required for marginal mesoderm formation 相似文献
52.
Wataru Ohira Kiyoshi Honda Masahiko Nagai Anuchit Ratanasuwan 《Trees - Structure and Function》2013,27(1):141-148
The submerged tree volume and the projection area of mangroves play a significant role in damping tsunami inundation flow with a distinct root formation above ground. We modeled the stilt root morphology of the Rhizophora sp., especially to incorporate into a hydraulic drag of tsunami inundation simulation. The equivalent Manning’s roughness coefficient has been used as the hydraulic drag of mangroves for the computation of inundation flow [Yanagisawa et al. (Coast Shelf Sci 81: 27–37, 2009)], but it could not elucidate the effectiveness under different tree conditions. The field data from 18 sample trees in Ranong Province, Thailand, were measured. The total number of primary roots, the root height at trunk, and the root-spread distance, the root diameter, and the vertical root angle from trunk could be estimated with the diameter of the breast height. The quadratic equation expressed the root curve of the primary stilt root, and functions to estimate root volume and projected area were derived by the integration of the equation that will be used to calculate drag force in tsunami simulation. 相似文献
53.
Acid hydrolysis of cytosinine gave each one mole of cytosine, levulinic acid, ammonia and carbon dioxide. Reduction of cytosinine with PtO2 afforded a mixture of dihydrocytosinine, 3-amino-tetrahydropyran-2-carboxylic acid and cytosine. Ozonolysis of N,N’-diacetylcytosinine methyl ester, followed by oxidation with hydrogen peroxide and acid hydrolysis gave erythro-d-β-hydroxyaspartic acid. These data permitted the assignment of structure (I) for cytosinine. Acid hydrolysis of uracinine gave uracil instead of cytosine, therefore, the structure (II) could be assigned to uracinine. Some stereochemical features and mechanism of levulinic acid formation were discussed. 相似文献
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Tsutomu Nakayama Motohisa Kaneko Masahiko Kodama 《Bioscience, biotechnology, and biochemistry》2013,77(12):3219-3220
Thermostable purine nucleoside phosphorylases, PUN PI and PUNPII, have been purified from Bacillus stearothermophilus JTS 859. The characterization of PUNPI was reported previously. [Hori et al.9 Agric. Biol. Chem. 53, 2205 (1989)] PUNPII had a molecular weight of 113,000, consisting of 4 identical subunits (Mw 28,000). The isoelectric point was 5.3. The Michaelis constants for inosine, guanosine, and adenosine were 0.22, 0.34, and 0.075 mm, respectively. The optimal temperature of the reaction was 70°C. The enzyme was stable at 70°C. Although other reported purine nucleoside phosphorylases were SH-enzymes, PUNPII was not a SH-enzyme because the enzyme reaction was not inhibited by PCMB and iodoacetic acid, the optimal pH of the enzyme reaction was from 7.0 to 11.0, and the enzyme did not contain cysteine.PUNPII and PUNPI were different in several points. Not PUNPI but PUNPII could catalyze the phosphorolysis of adenosine. Specific activity of PUNPI and II for inosine were 405 and 50.6 μmol/min/mg protein at 60°C, respectively. PUNPI was stable at 80°C. PUNPII was stable at 70°C, but was denatured at 80°C. 相似文献
56.
Masahiko Ishida Hideo Nagayama Kensuke Shimura 《Bioscience, biotechnology, and biochemistry》2013,77(8):1881-1892
The biosynthetic pathway of vitamin B6 (abbreviated as Be) has been studied with the cell-suspension of B6-producing bacteria, Achromobacter cycloclastes A.M.S. 6201. The distribution of 14C in the Be molecule prepared with the cell-suspensions containing glycerol-1,3-14C, glycerol-2-14C or γ-aminobutyric acid-U-14C was investigated by using three novel degradation methods. The results showed that carbon skeletons of glycerol and γ-aminobutyric acid were used for the formation of the major part of B6 carbon skeleton respectively. The implication of these compounds as precursors of B6 was discussed. 相似文献
57.
Masahiko Kito Daichi Maeda Yukitsugu Kudo-Asabe Naoki Sato Ie-Ming Shih Tian-Li Wang Masamitsu Tanaka Yukihiro Terada Akiteru Goto 《PloS one》2016,11(6)
There is a growing body of evidence regarding cell competition between normal and mutant mammalian cells, which suggest that it may play a defensive role in the early phase of carcinogenesis. In vitro study in the past has shown that overexpression of vimentin in normal epithelial cells at the contact surface with transformed cells is essential for the cell competition involved in epithelial defense against cancer. In this study, we attempted to examine cell competition in human tissue in vivo by investigating surgically resected human fallopian tubes that contain p53 signatures and serous tubal intraepithelial lesions (STILs), a linear expansion of p53-immunopositive/TP53 mutant tubal epithelial cells that are considered as precursors of pelvic high grade serous carcinoma. Immunofluorescence double staining for p53 and the cell competition marker vimentin was performed in 21 sections of human fallopian tube tissue containing 17 p53 signatures and 4 STILs. The intensities of vimentin expression at the interface between p53-positive cells at the end of the p53 signature/STIL and adjacent p53-negative normal tubal epithelial cells were compared with the background tubal epithelium. As a result, the average vimentin intensity at the interfaces relative to the background intensity was 1.076 (95% CI, 0.9412 – 1.211 for p53 signature and 0.9790 (95% CI, 0.7206 – 1.237) for STIL. Thus, it can be concluded that overexpression of the cell competition marker vimentin are not observed in human tissue with TP53 alterations. 相似文献
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Background & Objectives
Expertise of registered dietitians (RDs) is important for health guidance but has been poorly evaluated. We evaluated the kind of RD expertise that would improve their skills.Design, Setting, Participants, Measurements
This study was a post-hoc analysis of our randomized controlled trial, which compared the weight change between participants using the web-based self-disclosure health support and those using the email health support. Healthy men and women aged 35–64 years with a body mass index (BMI) of > = 24.5 kg/m2 were recruited for this study. We evaluated the relationship of RD expertise indicators including the duration of working as an RD, the experience of health counseling, and membership in the Japan Dietetic Association (JDA) with the weight loss of study participants. The primary endpoint was the change in body weight. Comparison of changes in body weight by the RD expertise indicators was evaluated using analysis of covariance.Results
A total of 175 participants were eligible for analyses. Changes in body weight were significantly greater when they were supported by the RDs in the routine counseling group than when supported by the RDs in the non-routine counseling group (-1.8 kg versus -0.4 kg, fully adjusted P = 0.0089). Duration of working as an RD and JDA membership did not significantly affect changes in body weight.Conclusions
Among some indices of RD experience, the experience of providing routine experience of health counseling was associated with weight loss. 相似文献60.