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891.
Eri Miyamoto-Mikami Koji Sato Toshiyuki Kurihara Natsuki Hasegawa Shumpei Fujie Satoshi Fujita Kiyoshi Sanada Takafumi Hamaoka Izumi Tabata Motoyuki Iemitsu 《PloS one》2015,10(3)
To elucidate the effects of endurance training on circulating irisin levels in young and middle-aged/older adults, and to determine the association between endurance training-induced alteration of irisin and reduction in body fat. Twenty-five healthy young (age 21 ± 1 years; 16 men, 9 women) and 28 healthy middle-aged/older adults (age 67 ± 8 years; 12 men, 16 women) participated in the study. Each age cohort was divided into two groups: the endurance-training group (14 young, 14 middle-aged/older) and the control group. Subjects in the training groups completed an 8-week endurance-training program (cycling at 60-70% peak oxygen uptake [O2peak] for 45 min, 3 days/week). Before and after the intervention, we evaluated serum irisin level, O2peak, and body composition. The increase in O2peak in the young and middle-aged/older training groups after the intervention period was significantly greater than those in the young and middle-aged/older control groups (P < 0.05). Serum irisin level was significantly increased in the middle-aged/older training group after the intervention period (P < 0.01), but not in the young training group. Furthermore, in the middle-aged/older training group, the endurance training-induced reduction in visceral adipose tissue area was negatively correlated with the change in serum irisin level (r = −0.54, P < 0.05). These results suggest a possible role for secreted irisin in the exercise-induced alteration of abdominal visceral fat in middle-aged and older adults. 相似文献
892.
893.
Kohta Suzuki Miri Sato Wei Zheng Ryoji Shinohara Hiroshi Yokomichi Zentaro Yamagata 《PloS one》2015,10(2)
Pregestational weight status and maternal smoking during pregnancy are significantly associated with fetal and childhood growth. However, few studies have examined associations between childhood growth and combinations of these factors using multilevel analysis. This study aimed to describe differences in childhood growth trajectories according to these combinations, using data from a prospective cohort study in Japan. The study participants were 1,973 women and their singletons, who were born between April 1, 1991 and March 31, 2003. Children were categorized according to whether they were born to normal-weight, nonsmoking mothers (NN); normal-weight, smoking mothers (NS); underweight, nonsmoking mothers (UN); underweight, smoking mothers (US); overweight, nonsmoking mothers (ON); or overweight, smoking mothers (OS). Birth weight and anthropometric data were collected from 1,965 children at birth (99.6%), 1,655 aged 3 (83.9%), 1,527 aged 5 (77.4%), 1,497 aged 7–8 (75.9%), and 1,501 aged 9–10 (76.1%). Multilevel analysis examining both individual and age as different level variables according to sex was used to describe the trajectories of body mass index z scores for statistical analyses. Although children of the OS group were the leanest at birth, their body mass indices had increased rapidly by 3 years of age. Moreover, body mass index was also likely to increase in boys in the NS and ON groups. A different trend was observed in girls. Body mass index decreased from 5 years of age in girls in the US group. There were no remarkable differences in body mass index trajectories between children in the other groups. In conclusion, childhood growth trajectories differed according to combinations of pregestational weight status and maternal smoking during pregnancy. Further, there were sex-related differences in the associations between childhood growth and factor combinations. 相似文献
894.
Insect–plant interactions are important to understanding the evolutionary mechanisms responsible for most of the diverse plant‐feeding insects. We aggregated data on sawfly–host plant associations and other resource associations from existing sources to address the following questions: (i) Is there a general correlation between host diversity and sawfly species richness? (ii) Is the pattern of host plant use consistent across sawfly lineages? and (iii) Is there a phylogenetically significant shift in species richness among sawflies? Our analysis comprised 8567 sawfly species, including 2087 species with host plant and other records. In total, there were 2126 records of host usage for sawflies, the overwhelming majority of which were sawflies using angiosperms as resources. Rosales are used by most of the species in sawfly families or subfamilies. We found that there was a strong correlation between the number of host plant orders and the species richness of sawfly families and subfamilies. To examine the points at which sawflies have experienced significant shifts in species richness, we compared sister taxon species richness. Several positive and negative shifts in species richness among sawflies were related to their range of host plant usage and specialized niche, respectively. In general, we found that most of the sawfly families and subfamilies used several orders as host plants, but mainly core eudicots, although some families or subfamilies were specialized on pteridophytes or gymnosperms. 相似文献
895.
Kyohei Baito Satomi Imai Makoto Matsushita Miku Otani Yu Sato Hiroyuki Kimura 《Microbial biotechnology》2015,8(5):837-845
In a deep aquifer associated with an accretionary prism, significant methane (CH4) is produced by a subterranean microbial community. Here, we developed bioreactors for producing CH4 and hydrogen (H2) using anaerobic groundwater collected from the deep aquifer. To generate CH4, the anaerobic groundwater amended with organic substrates was incubated in the bioreactor. At first, H2 was detected and accumulated in the gas phase of the bioreactor. After the H2 decreased, rapid CH4 production was observed. Phylogenetic analysis targeting 16S rRNA genes revealed that the H2-producing fermentative bacterium and hydrogenotrophic methanogen were predominant in the reactor. The results suggested that syntrophic biodegradation of organic substrates by the H2-producing fermentative bacterium and the hydrogenotrophic methanogen contributed to the CH4 production. For H2 production, the anaerobic groundwater, amended with organic substrates and an inhibitor of methanogens (2-bromoethanesulfonate), was incubated in a bioreactor. After incubation for 24 h, H2 was detected from the gas phase of the bioreactor and accumulated. Bacterial 16S rRNA gene analysis suggested the dominance of the H2-producing fermentative bacterium in the reactor. Our study demonstrated a simple and rapid CH4 and H2 production utilizing anaerobic groundwater containing an active subterranean microbial community. 相似文献
896.
897.
Takenori Dairaku Kyoko Furuita Hajime Sato Yoshinori Kondo Chojiro Kojima Akira Ono 《Nucleosides, nucleotides & nucleic acids》2015,34(12):877-900
Recently, we discovered novel silver(I)-mediated cytosine–cytosine base pair (C–AgI–C) in DNA duplexes. To understand the properties of these base pairs, we searched for a DNA sequence that can be used in NMR structure determination. After extensive sequence optimizations, a non-symmetric 15-base-paired DNA duplex with a single C–AgI–C base pair flanked by 14 A–T base pairs was selected. In spite of its challenging length for NMR measurements (30 independent residues) with small sequence variation, we could assign most non-exchangeable protons (254 out of 270) and imino protons for structure determination. 相似文献
898.
Akiko Takasuga Kunio Sato Ryouichi Nakamura Yosuke Saito Shinji Sasaki Takehito Tsuji Akio Suzuki Hiroshi Kobayashi Tamako Matsuhashi Koji Setoguchi Hiroshi Okabe Toshitake Ootsubo Ichiro Tabuchi Tatsuo Fujita Naoto Watanabe Takashi Hirano Shota Nishimura Toshio Watanabe Makio Hayakawa Yoshikazu Sugimoto Takatoshi Kojima 《PLoS genetics》2015,11(8)
Recessive skeletal dysplasia, characterized by joint- and/or hip bone-enlargement, was mapped within the critical region for a major quantitative trait locus (QTL) influencing carcass weight; previously named CW-3 in Japanese Black cattle. The risk allele was on the same chromosome as the Q allele that increases carcass weight. Phenotypic characterization revealed that the risk allele causes disproportional tall stature and bone size that increases carcass weight in heterozygous individuals but causes disproportionately narrow chest width in homozygotes. A non-synonymous variant of FGD3 was identified as a positional candidate quantitative trait nucleotide (QTN) and the corresponding mutant protein showed reduced activity as a guanine nucleotide exchange factor for Cdc42. FGD3 is expressed in the growth plate cartilage of femurs from bovine and mouse. Thus, loss of FDG3 activity may lead to subsequent loss of Cdc42 function. This would be consistent with the columnar disorganization of proliferating chondrocytes in chondrocyte-specific inactivated Cdc42 mutant mice. This is the first report showing association of FGD3 with skeletal dysplasia. 相似文献
899.
900.
Root-associated fungi, including ectomycorrhizal and root-endophytic fungi, are among the most diverse and important belowground plant symbionts in dipterocarp rainforests. Our study aimed to reveal the biodiversity, host association, and community structure of ectomycorrhizal Basidiomycota and root-associated Ascomycota (including root-endophytic Ascomycota) in a lowland dipterocarp rainforest in Southeast Asia. The host plant chloroplast ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) region and fungal internal transcribed spacer 2 (ITS2) region were sequenced using tag-encoded, massively parallel 454 pyrosequencing to identify host plant and root-associated fungal taxa in root samples. In total, 1245 ascomycetous and 127 putative ectomycorrhizal basidiomycetous taxa were detected from 442 root samples. The putative ectomycorrhizal Basidiomycota were likely to be associated with closely related dipterocarp taxa to greater or lesser extents, whereas host association patterns of the root-associated Ascomycota were much less distinct. The community structure of the putative ectomycorrhizal Basidiomycota was possibly more influenced by host genetic distances than was that of the root-associated Ascomycota. This study also indicated that in dipterocarp rainforests, root-associated Ascomycota were characterized by high biodiversity and indistinct host association patterns, whereas ectomycorrhizal Basidiomycota showed less biodiversity and a strong host phylogenetic preference for dipterocarp trees. Our findings lead to the working hypothesis that root-associated Ascomycota, which might be mainly represented by root-endophytic fungi, have biodiversity hotspots in the tropics, whereas biodiversity of ectomycorrhizal Basidiomycota increases with host genetic diversity. 相似文献