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31.
Taxonomy of the little‐studied brown algal species Punctaria mageshimensis (Ectocarpales s.l.) was reexamined by molecular phylogeny and morphology. In the genetic analyses of newly collected specimens using plastid rbcL and psaA gene sequences, the specimens morphologically referable to P. mageshimensis were phylogenetically distant from Ectocarpales s.l. and were included in the clade of Spatoglossum (Dictyotales). Morphological reexamination of the type specimen and newly collected specimens confirmed its systematic position in Dictyotales: Branched thallus; cushion‐shaped rhizoidal holdfast occasionally forming secondary holdfast at the bottom of the thallus; many discoidal plastids without pyrenoid per cell; tetrasporangium‐like reproductive structures with dark, homogeneous cell content; occurrence of hair tufts. Genetically P. mageshimensis was most related to a reported sequence of Spatoglossum asperum, but P. mageshimensis was considerably different from S. asperum as well as other known Spatoglossum species in the deep habitat and in having scarcely‐branched lanceolate and considerably thickened thallus. In conclusion, we propose the transfer of P. mageshimensis to Spatoglossum as S. mageshimense comb. nov. 相似文献
32.
Abstract The objective of this study was to investigate at the molecular level the heat shock response in olive by identifying sequences coding for heat shock proteins (HSPs). Young twigs of Olea europaea trees (cv Cellina di Nardò) were subjected to different temperature treatments in order to induce the expression of heat shock genes. In order to identify genes induced by heat treatment, we used a PCR-based approach to amplify specific HS cDNAs. Search for low molecular weight HSP sequences was performed in public domain databases in order to design specific primers based upon multisequence alignments. By this approach, we isolated the first full length cDNA encoding a low-molecular weight HSP from O. europaea. This is a class I low molecular weight HSP of 18.3 kDa, which is highly expressed in young twigs subjected to heat stress. 相似文献
33.
Shutaro Ishimura Masato Furuhashi Yuki Watanabe Kyoko Hoshina Takahiro Fuseya Tomohiro Mita Yusuke Okazaki Masayuki Koyama Marenao Tanaka Hiroshi Akasaka Hirofumi Ohnishi Hideaki Yoshida Shigeyuki Saitoh Tetsuji Miura 《PloS one》2013,8(11)
Objective
Fatty acid-binding proteins (FABPs) are a family of 14-15-kDa proteins, and some FABPs have been to be used as biomarkers of tissue injury by leak from cells. However, recent studies have shown that FABPs can be secreted from cells into circulation. Here we examined determinants and roles of circulating FABPs in a general population.Methods
From the database of the Tanno-Sobetsu Study, a study with a population-based cohort design, data in 2011 for 296 subjects on no medication were retrieved, and FABP1∼5 in their serum samples were assayed.Results
Level of FABP4, but not the other isoforms, showed a gender difference, being higher in females than in males. Levels of all FABPs were negatively correlated with estimated glomerular filtration rate (eGFR), but a distinct pattern of correlation with other clinical parameters was observed for each FABP isoform; significant correlates were alanine aminotransferase (ALT), blood pressure (BP), and brain natriuretic peptide (BNP) for FABP1, none besides eGFR for FABP2, age, BP, and BNP for FABP3, age, waist circumference (WC), BP, BNP, lipid variables, high-sensitivity C-reactive protein (hsCRP), and HOMA-R for FABP4, and age, WC, BP, ALT, BNP, and HOMA-R for FABP5. FABP4 is the most strongly related to metabolic markers among FABPs. In a multivariate regression analysis, FABP4 level was an independent predictor of HOMA-R after adjustment of age, gender, WC, BP, HDL cholesterol, and hsCRP.Conclusions
Each FABP isoform level showed a distinct pattern of correlation with clinical parameters, although levels of all FABPs were negatively determined by renal function. Circulating FABP4 appears to be a useful biomarker for detecting pre-clinical stage of metabolic syndrome, especially insulin resistance, in the general population. 相似文献34.
Homma Yuri Mita Kazuei Nakamura Yuki Namiki Toshiki Noda Hiroaki Shinoda Tetsuro Togawa Toru 《Applied Entomology and Zoology》2020,55(1):45-54
Applied Entomology and Zoology - Juvenile hormone (JH) has crucial roles in insect physiology, including development, reproduction, and polyphenism. JH is synthesized in the corpora allata (CA)... 相似文献
35.
Flemming Cornelius Ryuta Kanai Chikashi Toyoshima 《The Journal of biological chemistry》2013,288(9):6602-6616
The Na,K-ATPase is specifically inhibited by cardiotonic steroids (CTSs) like digoxin and is of significant therapeutic value in the treatment of congestive heart failure and arrhythmia. Recently, new interest has arisen in developing Na,K-ATPase inhibitors as anticancer agents. In the present study, we compare the potency and rate of inhibition as well as the reactivation of enzyme activity following inhibition by various cardiac glycosides and their aglycones at different pH values using shark Na,K-ATPase stabilized in the E2MgPi or in the E2BeFx conformations. The effects of the number and nature of various sugar residues as well as changes in the positions of hydroxyl groups on the β-side of the steroid core of cardiotonic steroids were investigated by comparing various cardiac glycoside compounds like ouabain, digoxin, digitoxin, and gitoxin with their aglycones. The results confirm our previous hypothesis that CTS binds primarily to the E2-P ground state through an extracellular access channel and that binding of extracellular Na+ ions to K+ binding sites relieved the CTS inhibition. This reactivation depended on the presence or absence of the sugar moiety on the CTS, and a single sugar is enough to impede reactivation. Finally, increasing the number of hydroxyl groups of the steroid was sterically unfavorable and was found to decrease the inhibitory potency and to confer high pH sensitivity, depending on their position on the steroid β-face. The results are discussed with reference to the recent crystal structures of Na,K-ATPase in the unbound and ouabain-bound states. 相似文献
36.
Ryuta Uraki Maki Kiso Kiyoko Iwatsuki-Horimoto Satoshi Fukuyama Emi Takashita Makoto Ozawa Yoshihiro Kawaoka 《Journal of virology》2013,87(14):7874-7881
Vaccination is an effective means to protect against influenza virus. Although inactivated and live-attenuated vaccines are currently available, each vaccine has disadvantages (e.g., immunogenicity and safety issues). To overcome these problems, we previously developed a replication-incompetent PB2-knockout (PB2-KO) influenza virus that replicates only in PB2 protein-expressing cells. Here, we generated two PB2-KO viruses whose PB2-coding regions were replaced with the HA genes of either A/California/04/2009 (H1N1pdm09) or A/Vietnam/1203/2004 (H5N1). The resultant viruses comparably, or in some cases more efficiently, induced virus-specific antibodies in the serum, nasal wash, and bronchoalveolar lavage fluid of mice relative to a conventional formalin-inactivated vaccine. Furthermore, mice immunized with these PB2-KO viruses were protected from lethal challenges with not only the backbone virus strain but also strains from which their foreign HAs originated, indicating that PB2-KO viruses with antigenically different HAs could serve as bivalent influenza vaccines. 相似文献
37.
Rui Nouchi Yasuyuki Taki Hikaru Takeuchi Hiroshi Hashizume Takayuki Nozawa Toshimune Kambara Atsushi Sekiguchi Carlos Makoto Miyauchi Yuka Kotozaki Haruka Nouchi Ryuta Kawashima 《PloS one》2013,8(2)
Background
Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults.Methods
We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability).Results and Discussion
Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults.Conclusions
Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields.Trial Registration
UMIN Clinical Trial Registry 000005618. 相似文献38.
Yoritaka Akimoto Akitake Kanno Toshimune Kambara Takayuki Nozawa Motoaki Sugiura Eiichi Okumura Ryuta Kawashima 《PloS one》2013,8(3)
Although many studies have investigated the neural basis of top-down and bottom-up attention, it still requires refinement in both temporal and spatial terms. We used magnetoencephalography to investigate the spatiotemporal dynamics of high-gamma (52–100 Hz) activities during top-down and bottom-up visual attentional processes, aiming to extend the findings from functional magnetic resonance imaging and event-related potential studies. Fourteen participants performed a 3-stimulus visual oddball task, in which both infrequent non-target and target stimuli were presented. We identified high-gamma event-related synchronization in the left middle frontal gyrus, the left intraparietal sulcus, the left thalamus, and the visual areas in different time windows for the target and non-target conditions. We also found elevated imaginary coherence between the left intraparietal sulcus and the right middle frontal gyrus in the high-gamma band from 300 to 400 ms in the target condition, and between the left thalamus and the left middle frontal gyrus in theta band from 150 to 450 ms. In addition, the strength of high-gamma imaginary coherence between the left middle frontal gyrus and left intraparietal sulcus, between the left middle frontal gyrus and the right middle frontal gyrus, and the high-gamma power in the left thalamus predicted inter-subject variation in target detection response time. This source-level electrophysiological evidence enriches our understanding of bi-directional attention processes: stimulus-driven bottom-up attention orientation to a salient, but irrelevant stimulus; and top-down allocation of attentional resources to stimulus evaluation. 相似文献
39.
40.
Ronan Becheler Constance Xhaard Etienne K. Klein Katherine J. Hayden Pascal Frey Stéphane De Mita Fabien Halkett 《Ecology and evolution》2016,6(18):6625-6632
The genetic consequences of range expansions have generally been investigated at wide geographical and temporal scales, long after the colonization event. A unique ecological system enabled us to both monitor the colonization dynamics and decipher the genetic footprints of expansion over a very short time period. Each year an epidemic of the poplar rust (Melampsora larici‐populina) expands clonally and linearly along the Durance River, in the Alps. The colonization dynamics observed in 2004 showed two phases with different genetic outcomes. Upstream, fast colonization maintained high genetic diversity. Downstream, the colonization wave progressively faltered, diversity eroded, and differentiation increased, as expected under recurrent founder events. In line with the high dispersal abilities of rust pathogens, we provide evidence for leapfrog dispersal of clones. Our results thus emphasize the importance of colonization dynamics in shaping spatial genetic structure in the face of high gene flow. 相似文献