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891.
892.
Yasuhiro Sato Tetsuhiro Kawagoe Yuji Sawada Masami Yokota Hirai Hiroshi Kudoh 《Evolutionary ecology》2014,28(3):545-559
Frequency-dependent prey choice by natural enemies may influence the coexistence of multiple prey types, but little is known about whether frequency-dependent foraging choice occurs in herbivory on plants showing resistance polymorphism within a single population. Here we examined frequency-dependent foraging by a crucifer-feeding leaf beetle, Phaedon brassicae, on trichome-producing (hairy) and trichomeless (glabrous) plants coexisting within a natural population of the perennial herb Arabidopsis halleri subsp. gemmifera. Larvae of P. brassicae fed on hairy leaves showed slower growth than those fed on glabrous leaves. Although adult beetles consumed similar amounts of leaves when they were fed either hairy or glabrous leaves in no-choice conditions, our choice experiment showed that adult beetles fed at less than the proportionally expected level on hairy leaves compared to glabrous leaves when the hairy leaves were less or equally abundant. Both types of leaves were consumed at the proportionally expected levels when the hairy leaves were more abundant than the glabrous leaves. In a natural population, the leaf damage on the hairy plants was negatively correlated with the local proportion of the glabrous plants in a 1-m diameter patch across 2 years, while correlations between the leaf damage on the glabrous plants and their proportion differed between the 2 years. Additionally, we found five glucosinolates in leaves of A. halleri, but their accumulation did not differ between hairy and glabrous plants. Our experimental results indicate that hairy plants incur less herbivory by P. brassicae when glabrous plants are abundant. The field pattern provides evidence suggestive of frequency-dependent herbivory acting on hairy plants. The present study highlights one of the putative mechanisms of maintaining plant resistance polymorphism. 相似文献
893.
894.
895.
Kansuporn Sriyudthsak Michio Iwata Masami Yokota Hirai Fumihide Shiraishi 《Bulletin of mathematical biology》2014,76(6):1333-1351
The availability of large-scale datasets has led to more effort being made to understand characteristics of metabolic reaction networks. However, because the large-scale data are semi-quantitative, and may contain biological variations and/or analytical errors, it remains a challenge to construct a mathematical model with precise parameters using only these data. The present work proposes a simple method, referred to as PENDISC ( arameter stimation in a on- mensionalized -system with onstraints), to assist the complex process of parameter estimation in the construction of a mathematical model for a given metabolic reaction system. The PENDISC method was evaluated using two simple mathematical models: a linear metabolic pathway model with inhibition and a branched metabolic pathway model with inhibition and activation. The results indicate that a smaller number of data points and rate constant parameters enhances the agreement between calculated values and time-series data of metabolite concentrations, and leads to faster convergence when the same initial estimates are used for the fitting. This method is also shown to be applicable to noisy time-series data and to unmeasurable metabolite concentrations in a network, and to have a potential to handle metabolome data of a relatively large-scale metabolic reaction system. Furthermore, it was applied to aspartate-derived amino acid biosynthesis in Arabidopsis thaliana plant. The result provides confirmation that the mathematical model constructed satisfactorily agrees with the time-series datasets of seven metabolite concentrations. 相似文献
896.
Hideki Hirakawa Kenta Shirasawa Shunichi Kosugi Kosuke Tashiro Shinobu Nakayama Manabu Yamada Mistuyo Kohara Akiko Watanabe Yoshie Kishida Tsunakazu Fujishiro Hisano Tsuruoka Chiharu Minami Shigemi Sasamoto Midori Kato Keiko Nanri Akiko Komaki Tomohiro Yanagi Qin Guoxin Fumi Maeda Masami Ishikawa Satoru Kuhara Shusei Sato Satoshi Tabata Sachiko N. Isobe 《DNA research》2014,21(2):169-181
Cultivated strawberry (Fragaria x ananassa) is octoploid and shows allogamous behaviour. The present study aims at dissecting this octoploid genome through comparison with its wild relatives, F. iinumae, F. nipponica, F. nubicola, and F. orientalis by de novo whole-genome sequencing on an Illumina and Roche 454 platforms. The total length of the assembled Illumina genome sequences obtained was 698 Mb for F. x ananassa, and ∼200 Mb each for the four wild species. Subsequently, a virtual reference genome termed FANhybrid_r1.2 was constructed by integrating the sequences of the four homoeologous subgenomes of F. x ananassa, from which heterozygous regions in the Roche 454 and Illumina genome sequences were eliminated. The total length of FANhybrid_r1.2 thus created was 173.2 Mb with the N50 length of 5137 bp. The Illumina-assembled genome sequences of F. x ananassa and the four wild species were then mapped onto the reference genome, along with the previously published F. vesca genome sequence to establish the subgenomic structure of F. x ananassa. The strategy adopted in this study has turned out to be successful in dissecting the genome of octoploid F. x ananassa and appears promising when applied to the analysis of other polyploid plant species. 相似文献
897.
Yoshiaki Katsuda Takeshi Ohta Katsuhiro Miyajima Yusuke Kemmochi Tomohiko Sasase Bin Tong Masami Shinohara Takahisa Yamada 《Experimental Animals》2014,63(2):121-132
We overviewed the pathophysiological features of diabetes and its complications in obese
type 2 diabetic rat models: Otsuka Long-Evans Tokushima fatty (OLETF) rat, Wistar fatty
rat, Zucker diabetic fatty (ZDF) rat and Spontaneously diabetic Torii (SDT) fatty rat.
Pancreatic changes with progression of diabetes were classified into early changes, such
as islet hypertrophy and degranulation of β cells, and degenerative changes, such as islet
atrophy and fibrosis of islet with infiltration of inflammatory cells. Renal lesions in
tubuli and glomeruli were observed, and nodular lesions in glomeruli were notable changes
in OLETF and SDT fatty rats. Among retinal changes, folding and thickening were
interesting findings in SDT fatty rats. A decrease of motor nerve conduction velocity with
progression of diabetes was presented in obese diabetic rats. Other diabetic
complications, osteoporosis and sexual dysfunction, were also observed. Observation of
bone metabolic abnormalities, including decrease of osteogenesis and bone mineral density,
and sexual dysfunction, including hypotestosteronemia and erectile dysfunction, in obese
type 2 diabetic rats have been reported. 相似文献
898.
Moeko Noguchi-Shinohara Sohshi Yuki Chiaki Dohmoto Yoshihisa Ikeda Miharu Samuraki Kazuo Iwasa Masami Yokogawa Kimiko Asai Kiyonobu Komai Hiroyuki Nakamura Masahito Yamada 《PloS one》2014,9(5)
Our objective was to determine whether the consumption of green tea, coffee, or black tea influences the incidence of dementia and mild cognitive impairment (MCI) in older people. We conducted a population-based prospective study with Japanese residents aged >60 years from Nakajima, Japan (the Nakajima Project). Participants received an evaluation of cognitive function and blood tests. The consumption of green tea, coffee, and black tea was also evaluated at baseline. Of 723 participants with normal cognitive function at a baseline survey (2007–2008), 490 completed the follow up survey in 2011–2013. The incidence of dementia during the follow-up period (mean ± SD: 4.9±0.9 years) was 5.3%, and that of MCI was 13.1%. The multiple-adjusted odds ratio for the incidence of overall cognitive decline (dementia or MCI) was 0.32 (95% CI: 0.16–0.64) among individuals who consumed green tea every day and 0.47 (95% CI: 0.25–0.86) among those who consumed green tea 1–6 days per week compared with individuals who did not consume green tea at all. The multiple-adjusted odds ratio for the incidence of dementia was 0.26 (95% CI: 0.06–1.06) among individuals who consumed green tea every day compared with those who did not consume green tea at all. No association was found between coffee or black tea consumption and the incidence of dementia or MCI. Our results indicate that green tea consumption is significantly associated with reduced risk of cognitive decline, even after adjustment for possible confounding factors. 相似文献
899.
900.
Hiromichi Takahashi Yoshihiro Hatta Noriyoshi Iriyama Yuichiro Hasegawa Hikaru Uchida Masaru Nakagawa Makoto Makishima Jin Takeuchi Masami Takei 《PloS one》2014,9(11)
Retinoids and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) induce differentiation of myeloid leukemia cells into granulocyte and macrophage lineages, respectively. All-trans retinoic acid (ATRA), which is effective in the treatment of acute promyelocytic leukemia, can induce differentiation of other types of myeloid leukemia cells, and combined treatment with retinoid and 1,25(OH)2D3 effectively enhances the differentiation of leukemia cells into macrophage-like cells. Recent work has classified macrophages into M1 and M2 types. In this study, we investigated the effect of combined treatment with retinoid and 1,25(OH)2D3 on differentiation of myeloid leukemia THP-1 and HL60 cells. 9-cis Retinoic acid (9cRA) plus 1,25(OH)2D3 inhibited proliferation of THP-1 and HL60 cells and increased myeloid differentiation markers including nitroblue tetrazolium reducing activity and expression of CD14 and CD11b. ATRA and the synthetic retinoic acid receptor agonist Am80 exhibited similar effects in combination with 1,25(OH)2D3 but less effectively than 9cRA, while the retinoid X receptor agonist HX630 was not effective. 9cRA plus 1,25(OH)2D3 effectively increased expression of M2 macrophage marker genes, such as CD163, ARG1 and IL10, increased surface CD163 expression, and induced interleukin-10 secretion in myeloid leukemia cells, while 9cRA alone had weaker effects on these phenotypes and 1,25(OH)2D3 was not effective. Taken together, our results demonstrate selective induction of M2 macrophage markers in human myeloid leukemia cells by combined treatment with 9cRA and 1,25(OH)2D3. 相似文献