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71.
Japanese monkeys, Macaca fuscata, living in a cool temperate forest experienced energy crises in winter. We measured feeding times and feeding rates (mass of foods eaten per unit time of feeding) in six different-sized, age–sex classes (1.2–12.6 kg body mass) in autumn and winter. One-, 2- and 3~4-year-olds spent 34–35% and 44–46% of the day feeding in autumn and winter, respectively. Monkeys less than 0 years old spent less time feeding (16–28%) than average in winter and autumn; adult females spent less (41%) in winter; and adult males spent less (25%) in autumn. All age–sex classes ate mainly fruits in autumn and the heavier classes fed more on tree bark than buds in winter. The feeding rate for fruits (2.3–53.5 g min–1) was nine to 12 times faster than those for buds (1.0– 4.8 g min–1) and bark (0.5–4.4 g min–1), and energy content did not differ among fruits (22.1 kJ g–1 dry mass), buds (19.9 kJ g–1 dry mass) and bark (23.2 kJ g–1 dry mass). Energy base feeding rates increased with body mass where the body mass exponent for buds (0.29) was smaller than those for bark (0.64) and fruits (0.63), which might be attributable to the unit size of food items and mass dependency of masticatory apparatus. Our monkeys obtained two to five times more energy in autumn (1567–1150 kJ day–1) than in winter (604–3020 kJ day–1). Adult females obtained 60% of expected energy expenditure and other classes obtained 77–88% of that in winter. 相似文献
72.
Nishino Y Yamamoto K Kimura S Kikuchi A Shiro Y Iyanagi T 《Archives of biochemistry and biophysics》2007,465(1):254-265
The object of this study was to clarify the mechanism of electron transfer in the human endothelial nitric oxide synthase (eNOS) reductase domain using recombinant eNOS reductase domains; the FAD/NADPH domain containing FAD- and NADPH-binding sites and the FAD/FMN domain containing FAD/NADPH-, FMN-, and a calmodulin-binding sites. In the presence of molecular oxygen or menadione, the reduced FAD/NADPH domain is oxidized via the neutral (blue) semiquinone (FADH(*)), which has a characteristic absorption peak at 520 nm. The FAD/NADPH and FAD/FMN domains have high activity for ferricyanide, but the FAD/FMN domain has low activity for cytochrome c. In the presence or absence of calcium/calmodulin (Ca(2+)/CaM), reduction of the oxidized flavins (FAD-FMN) and air-stable semiquinone (FAD-FMNH(*)) with NADPH occurred in at least two phases in the absorbance change at 457nm. In the presence of Ca(2+)/CaM, the reduction rate of both phases was significantly increased. In contrast, an absorbance change at 596nm gradually increased in two phases, but the rate of the fast phase was decreased by approximately 50% of that in the presence of Ca(2+)/CaM. The air-stable semiquinone form was rapidly reduced by NADPH, but a significant absorbance change at 520 nm was not observed. These findings indicate that the conversion of FADH(2)-FMNH(*) to FADH(*)-FMNH(2) is unfavorable. Reduction of the FAD moiety is activated by CaM, but the formation rate of the active intermediate, FADH(*)-FMNH(2) is extremely low. These events could cause a lowering of enzyme activity in the catalytic cycle. 相似文献
73.
To understand how baidzharakhs (relic mounds enclosing polygonal ice blocks in permafrost) affect the zonal distribution of
vegetation, vegetation was measured in 145 plots of area 50 cm × 50 cm on a coastal terrace facing the Arctic Ocean in northern
Siberia. Cluster analysis classified five community types that were zonally distributed along the coastline. α-diversities
(species richness and diversity) were not different among vegetation types except for vegetation close to the coastline. On
and around baidzharakhs, burrows created by lemmings were frequently observed, and plant cover was low, suggesting that baidzharakhs
support habitats for rodents. Disturbances by rodent habits caused plant cover to decline but did not change α-diversity.
Two vegetation types that developed only on baidzharakhs were found at intermediate distances between the seacoast and inland
areas. Because these two vegetation types are azonally distributed, β- and γ-diversities were increased by permafrost-derived
topography, i.e., baidzharakh, and/or disturbance by rodents of which suitable nesting habitat is provided by baidzharakh. 相似文献
74.
Ganoderic acid C, a new lanostane-type triterpenoid was isolated from the fruit body of Ganoderma lucidum. The structure of ganoderic acid C was elucidated by spectroscopic data and X-ray analysis of methyl ganoderate C acetate. 相似文献
75.
Keishi Abe Yoichi Otsuka Minoru Yasujima Satoru Ciba Masahide Seino Nobuo Irokawa Kaoru Yoshinaga Fumio Hirata Shiro Ohki Nobuhiko Nakazawa Toshio Hanyu 《Prostaglandins & other lipid mediators》1976,12(5):843-848
The excretion rates of main urinary metabolite of PG F2α were measured radioimmunologically in 4 healthy persons and in 13 essential hypertensives. The resting values were 9.3±0.73 in the former and 10.4±2.17 ng/min in the latter. There was no significant differences between them. The excretion of the metabolite decresed prominently after the administration of furosemide. The percent decrease was 57% in healthy persons and 70% in essential hypertension. The percent result supports that furosemide inhibit the catabolism of PG F2α. 相似文献
76.
Downregulation of p‐COUMAROYL ESTER 3‐HYDROXYLASE in rice leads to altered cell wall structures and improves biomass saccharification 下载免费PDF全文
Yuri Takeda Yuki Tobimatsu Steven D. Karlen Taichi Koshiba Shiro Suzuki Masaomi Yamamura Shinya Murakami Mai Mukai Takefumi Hattori Keishi Osakabe John Ralph Masahiro Sakamoto Toshiaki Umezawa 《The Plant journal : for cell and molecular biology》2018,95(5):796-811
p‐Coumaroyl ester 3‐hydroxylase (C3′H) is a key enzyme involved in the biosynthesis of lignin, a phenylpropanoid polymer that is the major constituent of secondary cell walls in vascular plants. Although the crucial role of C3′H in lignification and its manipulation to upgrade lignocellulose have been investigated in eudicots, limited information is available in monocotyledonous grass species, despite their potential as biomass feedstocks. Here we address the pronounced impacts of C3′H deficiency on the structure and properties of grass cell walls. C3′H‐knockdown lines generated via RNA interference (RNAi)‐mediated gene silencing, with about 0.5% of the residual expression levels, reached maturity and set seeds. In contrast, C3′H‐knockout rice mutants generated via CRISPR/Cas9‐mediated mutagenesis were severely dwarfed and sterile. Cell wall analysis of the mature C3′H‐knockdown RNAi lines revealed that their lignins were largely enriched in p‐hydroxyphenyl (H) units while being substantially reduced in the normally dominant guaiacyl (G) and syringyl (S) units. Interestingly, however, the enrichment of H units was limited to within the non‐acylated lignin units, with grass‐specific γ‐p‐coumaroylated lignin units remaining apparently unchanged. Suppression of C3′H also resulted in relative augmentation in tricin residues in lignin as well as a substantial reduction in wall cross‐linking ferulates. Collectively, our data demonstrate that C3′H expression is an important determinant not only of lignin content and composition but also of the degree of cell wall cross‐linking. We also demonstrated that C3′H‐suppressed rice displays enhanced biomass saccharification. 相似文献
77.
Shiro Higashi Akinori Nakashima Hideki Ozaki Mikiko Abe Toshiki Uchiumi 《Journal of plant research》1993,106(1):47-54
The process of digestion of captured feeds in a pitcher, an insect-trapping organ, ofNepenthes was studied. Changes in bacterial population, pH and NH4
+ concentrations in pitcher juice were examined. Strong activities of both acid- and alkaline phosphatase, phosphoamidase,
esterase C4 and esterase C8 were found in the pitcher juice. Optimum pH of proteases in the juice and those secreted from
bacteria showed pH 3.0 and pH 8.0–9.0, respectively. Twenty six strains of bacteria were isolated from 4 pitchers: 10 strains
were gram positive, 16 strains were gram negative (10 strains had casein hydrolase activity). A proton excretion was induced
by NH4
+ released from the added solutions, and accordingly, the pH of the solutions fell. As a simulation model of the digestion
process of feeds in pitcher juice and polypeptone solution was added into the washed pitcher. A good correlation was found
among the NH4
+ concentration, pH and bacterial cell titer. 相似文献
78.
Asami Nishimori Satoru Konnai Ryoyo Ikebuchi Tomohiro Okagawa Chie Nakajima Yasuhiko Suzuki Claro N. Mingala Shiro Murata Kazuhiko Ohashi 《Microbiology and immunology》2014,58(7):388-397
Previous reports from this group have indicated that the immunoinhibitory programmed death (PD)‐1 receptor and its ligand, PD‐L1, are involved in the mechanism of immune evasion of bovine chronic infection. However, no functional analysis of bovine PD‐L2 in cattle has been reported. Thus, in this study, the molecular function of bovine PD‐L2 was analyzed in vitro. Recombinant PD‐L2 (PD‐L2‐Ig), which comprises an extracellular domain of bovine PD‐L2 fused to the Fc portion of rabbit IgG1, was prepared based on the cloned cDNA sequence for bovine PD‐L2. Bovine PD‐L2‐Ig bound to bovine PD‐1‐expressing cells and addition of soluble bovine PD‐1‐Ig clearly inhibited the binding of PD‐L2‐Ig to membrane PD‐1 in a dose‐dependent manner. Cell proliferation and IFN‐γ production were significantly enhanced in the presence of PD‐L2‐Ig in peripheral blood mononuclear cells (PBMCs) from cattle. Moreover, PD‐L2‐Ig significantly enhanced IFN‐γ production from virus envelope peptides‐stimulated PBMCs derived from bovine leukemia virus‐infected cattle. Interestingly, PD‐L2‐Ig‐induced IFN‐γ production was further enhanced by treatment with anti‐bovine PD‐1 antibody. These data suggest potential applications of bovine PD‐L2‐Ig as a therapy for bovine diseases. 相似文献
79.
Le Van Phung Yuki Han Shiro Oka Hisako Hotta Michael D. Smith Prapit Theeparakun Eiko Yabuuchi Ikuya Yano 《FEMS immunology and medical microbiology》1995,12(3-4):259-264
Abstract The serodiagnosis of melioidosis is commonly performed with tests using protein or polysaccharide as antigen. However, due to the low sensitivity, specificity and difficulty in the preparation of the antigens, more simple, precise and reproducible diagnostic tests were required. A purified glycolipid antigen (GL) which is a specific lipid component of Burkholderia pseudomallei has been used in an ELISA. With this antigen, specific immunoglobulin G (IgG) was detected in 49 out of 50 melioidosis sera. IgG was also detected in 2 out of 185 (Japanese) and 16 out of 181 (Vietnamese) control sera. Thus, the sensitivity was 98.0%, and specificity was 98.9% and 91.1% in the Japanese and Vietnamese sera, respectively. When the ELISA and indirect haemagglutination (IHA) tests were combined, a sensitivity of 100% and specificity of 97.8% were achieved. The advantages of the glycolipid antigen are ease of preparation, stability, high sensitivity and specificity. 相似文献
80.
Mizuno S Yasuo M Bogaard HJ Kraskauskas D Alhussaini A Gomez-Arroyo J Farkas D Farkas L Voelkel NF 《PloS one》2012,7(1):e30678