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91.
Ryohei Shimoda Kohei Okabe Toshihisa Kotake Koji Matsuoka Tetsuo Koyama Theodora Tryfona 《Bioscience, biotechnology, and biochemistry》2013,77(5):818-831
We investigated the structures of L-arabino-galactooligosaccharides released from the sugar moieties of a radish arabinogalactan-protein (AGP) by the action of exo-β-(1→3)-galactanase. We detected a series of neutral β-(1→6)-linked galactooligosaccharides forming branches of one to up to at least 19 consecutive Gal groups, together with corresponding acidic derivatives terminating in 4-O-methyl-glucuronic acid (4-Me-GlcA) at the non-reducing end. Some oligosaccharide chains of degree of polymerization (dp) higher than 3 for neutral, and 4 for acidic oligomers were modified with L-Araf residues. The acidic tetrasaccharide 4-Me-β-GlcA-(1→6)[α-L-Araf-(1→3)]-β-Gal-(1→6)-Gal was detected as an abundant L-Araf-containing oligosaccharide among these neutral and acidic oligomers. A pentasaccharide containing an additional L-Araf group attached to the L-Ara in the tetrasaccharide through an α-(1→5)-linkage was also found. We observed L-arabino-galactooligosaccharides substituted with single or disaccharide L-Araf units at different Gal residues along these neutral and acidic β-(1→6)-galactooligosaccharide chains, indicating that these side chains are highly variable in length and substituted variously with L-Araf residues. 相似文献
92.
Koichi Koshimizu Hiroshi Fukui Toshiatsu Kusaki Yukiyoshi Ogawa Tetsuo Mitsui 《Bioscience, biotechnology, and biochemistry》2013,77(9):1135-1140
A new gibberellin, tentatively called Lupinus gibberellin I, was isolated from young yellow lupin seeds. It has been shown to have structure (X), and now named gibberellin A18. 相似文献
93.
A comparative study of inhibition on the substrate-incorporation in several species of tumor cells has been achieved in combination with the antibiotics having different action mechanisms. It was thus revealed that a large part of the antitumor antibiotics so far examined showed a marked inhibitory response even at a low concentration. Particularly, the antibiotics whose action mechanism were established primarily on cell membrane were markedly sensitive. An apparent difference in the sensitivity was observed in some groups of antitumor antibiotics which act on nucleic acid synthesis. A methodological survey together with an evaluation of this procedure is discussed. 相似文献
94.
Tetsuo Nakano Ei-Tora Yamamura Hiroshi Fujita Teruo Sone Kozo Asano 《Bioscience, biotechnology, and biochemistry》2013,77(11):1889-1901
ABSTRACTPolyinosinic-polycytidylic acid (PIC), a double-stranded RNA that induces innate immunity in mammals, is a candidate immunopotentiator for pharmaceuticals. The potency and adverse effects of PIC are strongly correlated with the nucleotide length, and the inability to precisely control the length in PIC production limits its practical use. Length extension during the annealing process is the major factor underlying the lack of control, but tuning the annealing conditions is insufficient to resolve this issue. In this study, we developed a novel method to produce accurate nucleotide length PIC at an industrial scale. The length extension was significantly suppressed by the assembly of multiple short polyinosinic acid molecules with one long polycytidylic acid molecule. A newly developed PIC, uPIC100-400, demonstrated a reproducible length and better storage stability than that of corresponding evenly structured PIC. Human dsRNA receptors exhibited equivalent responsiveness to uPIC100-400 and the evenly structured PIC with the same length. 相似文献
95.
Recent molecular phylogenetic studies reported high diversity of Ruppia species in the Mediterranean. Multiple taxa, including apparent endemics, are known from that region, however, they have thus far not been exposed to phylogenetic analyses aimed at studying their relationships to taxa from other parts of the world. Here we present a comprehensive phylogenetic analyses of the R. maritima complex using data sets composed of DNA sequences of the plastid genome, the multi-copy nuclear ITS region, and the low-copy nuclear phyB gene with a primary focus on the Mediterranean representatives of the complex. As a result, a new lineage, “Drepanensis”, was identified as the seventh entity of the complex. This lineage is endemic to the Mediterranean. The accessions included in the former “Tetraploid” entity were reclassified into two entities: an Asia–Australia–Europe disjunct “Tetraploid_α” with a paternal “Diploid” origin, and a European “Tetraploid_γ” originating from a maternal “Drepanensis” lineage. Another entity, “Tetraploid_β”, is likely to have been originated as a result of chloroplast capture through backcrossing hybridization between paternal “Tetraploid_α” and maternal “Tetraploid_γ”. Additional discovery of multiple tetraploidizations as well as hybridization and chloroplast capture at the tetraploid level indicated that hybridization has been a significant factor in the diversification of Ruppia. 相似文献
96.
Osami Akimitsu Kai Wada Teruki Noji Nozomi Taniwaki Milada Krejci Miyo Nakade Hitomi Takeuchi Tetsuo Harada 《Journal of physiological anthropology》2013,32(1):13
Background
This study aims to examine the relationship between tyrosine and phenylalanine intake at breakfast as precursors of dopamine, and scores on the Torsvall-Åkerstedt Diurnal Type Scale and of mental health in Japanese infants aged 2 to 5 years.Results
An integrated questionnaire was administered to parents of 1,367 infants attending one of ten nursery schools governed by Kochi City or a kindergarten affiliated with the Faculty of Education at Kochi University (775 answers for analysis: 56.7%) in May and June 2008. Questionnaires included the Torsvall-Åkerstedt Diurnal Type Scale and questions on sleep habits (onset, offset, quality, quantity, and so on), meal habits (content and regularity of timing), and mental health (depressive states). Amount of tyrosine and phenylalanine intake was calculated based on a breakfast content questionnaire and data on the components of amino acids in foods. Infants who ingested more than 800 mg of tyrosine or phenylalanine at breakfast per meal were more morning-type than those who ingested less than 800 mg (ANOVA: P= 0.005). However, this relationship disappeared in the ANCOVA analysis (with the covariance of tryptophan intake, P= 0.894). Infants who ingested more than 800 mg of the two amino acids at breakfast showed significantly higher mental health scores (lower frequency of depressive states) than those who ingested less than 800 mg (ANOVA: P = 0.004). This relationship remained significant when ANCOVA analysis was performed with the covariance of tryptophan (ANCOVA: P= 0.017).Conclusions
These results suggest that tyrosine and phenylalanine ingested at breakfast are not related with circadian phase, but are relate with mental health in infants. 相似文献97.
Yohei Takai Megumi Ohta Ryota Akagi Emika Kato Taku Wakahara Yasuo Kawakami Tetsuo Fukunaga Hiroaki Kanehisa 《Journal of physiological anthropology》2013,32(1):12
Background
The skeletal muscle mass of the lower limb plays a role in its mobility during daily life. From the perspective of physical resources, leg muscle mass dominantly decreases after the end of the fifth decade. Therefore, an accurate estimate of the muscle mass is important for the middle-aged and older population. The present study aimed to clarify the validity of ultrasound muscle thickness (MT) measurements for predicting leg skeletal muscle mass (SM) in the healthy Japanese middle-aged and older population.Findings
MTs at four sites of the lower limb and the bone-free lean tissue mass (LTM) of the right leg were determined using brightness-mode ultrasonography and dual-energy X-ray absorptiometry (DXA), respectively, in 44 women and 33 men, 52- to 78-years old. LTM was used as a representative variable of leg skeletal muscle mass. In the model-development group (30 women and 22 men), regression analysis produced an equation with R2 and standard error of the estimate (SEE) of 0.958 and 0.3 kg, respectively: LTM (kg) = 0.01464 × (MTSUM×L) (cm2) - 2.767, where MTSUM is the sum of the product of MTs at four sites, and L is length of segment where MT is determined. The estimated LTM (7.0 ± 1.7 kg) did not significantly differ from the measured LTM (7.0 ± 1.7 kg), without a significant systematic error on a Bland-Altman plot. The application of this equation for the cross-validation group (14 women and 11 men) did not yield a significant difference between the measured (7.2 ± 1.6 kg) or estimated (7.2 ± 1.6 kg) LTM and systematic error.Conclusion
The developed prediction equation may be useful for estimating the lean tissue mass of the lower extremity for the healthy Japanese middle-aged and older population. 相似文献98.
Physiological anthropology presently covers a very broad range of human knowledge and engineering technologies. This study reviews scientific inconsistencies within a variety of areas: sitting posture; negative air ions; oxygen inhalation; alpha brain waves induced by music and ultrasound; 1/f fluctuations; the evaluation of feelings using surface electroencephalography; Kansei; universal design; and anti-stress issues. We found that the inconsistencies within these areas indicate the importance of integrative thinking and the need to maintain the perspective on the biological benefit to humanity. Analytical science divides human physiological functions into discrete details, although individuals comprise a unified collection of whole-body functions. Such disparate considerations contribute to the misunderstanding of physiological functions and the misevaluation of positive and negative values for humankind. Research related to human health will, in future, depend on the concept of maintaining physiological functions based on consistent science and on sustaining human health to maintain biological welfare in future generations. 相似文献
99.
100.
Shigekazu Higuchi Sang-il Lee Tomoaki Kozaki Tetsuo Harada Ikuo Tanaka 《Chronobiology international》2016,33(4):448-452
Light is the strongest synchronizer of human circadian rhythms, and exposure to residential light at night reportedly causes a delay of circadian rhythms. The present study was conducted to investigate the association between color temperature of light at home and circadian phase of salivary melatonin in adults and children. Twenty healthy children (mean age: 9.7 year) and 17 of their parents (mean age: 41.9 years) participated in the experiment. Circadian phase assessments were made with dim light melatonin onset (DLMO). There were large individual variations in DLMO both in adults and children. The average DLMO in adults and in children were 21:50 ± 1:12 and 20:55 ± 0:44, respectively. The average illuminance and color temperature of light at eye level were 139.6 ± 82.7 lx and 3862.0 ± 965.6 K, respectively. There were significant correlations between color temperature of light and DLMO in adults (r = 0.735, p < 0.01) and children (r = 0.479, p < 0.05), although no significant correlations were found between illuminance level and DLMO. The results suggest that high color temperature light at home might be a cause of the delay of circadian phase in adults and children. 相似文献