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51.
Masako Kitajima Yoshiko Ohkura Takayoshi Shotake Ken Nozawa 《Primates; journal of primatology》1975,16(4):399-404
Genetic variation at the locus controlling A1 band of erythrocyte esterase was found in the Japanese macaque,Macaca fuscata. Existence of four alleles,Es-A 1 1 ,Es-A 1 2 ,Es-A 1 3 , andEs-A 1 4 , controlling the mobility of the band and codominance relation between them were postulated. A majority of the troops examined were monomorphic inEs-A 1 1-1 phenotype, and the variant phenotypes were observed to occur only in Yugawara-Ihama, Arashiyama, and Koshima areas. 相似文献
52.
Takahide Noguchi Yoshiko Banno Takashi Watanabe Yoshinori Nozawa Yuki Ito 《Mycopathologia》1975,55(2):71-76
In an attempt to evaluate taxonomic character of sugar composition of dermatophytes, the purified cell walls from 13 species are analyzed on neutral sugar composition by gas liquid chromatography. The results were principally compatible with those obtained by conventional morphological examination. Neutral sugar components of dermatophytes cell walls were mannose and glucose in the ratio of 1∶2.7 for Epidermophyton and 1∶1.4 for Microsporum. There were two types in Trichophyton, in which the ratios of mannose to glucose were 1∶1.6 and 1∶3.8. The cases of Trichophyton ferrugineum and Trichophyton mentagrophytes were exceptional. The ratio of the former was 1∶1.4, which implied the relation to Microsporum group, and the ratio of the latter was 1∶2.3, which was supposed to be the intermediate of two types of Trichophyton group. Albino type cell wall of Epidermophyton floccosum was more rich in glucose than pigmented type one. 相似文献
53.
Hiroyuki Koga Haruka Fujitani Yoshiaki Morino Norio Miyamoto Jun Tsuchimoto Tomoko F. Shibata Masafumi Nozawa Shuji Shigenobu Atsushi Ogura Kazunori Tachibana Masato Kiyomoto Shonan Amemiya Hiroshi Wada 《PloS one》2016,11(2)
Over the course of evolution, the acquisition of novel structures has ultimately led to wide variation in morphology among extant multicellular organisms. Thus, the origins of genetic systems for new morphological structures are a subject of great interest in evolutionary biology. The larval skeleton is a novel structure acquired in some echinoderm lineages via the activation of the adult skeletogenic machinery. Previously, VEGF signaling was suggested to have played an important role in the acquisition of the larval skeleton. In the present study, we compared expression patterns of Alx genes among echinoderm classes to further explore the factors involved in the acquisition of a larval skeleton. We found that the alx1 gene, originally described as crucial for sea urchin skeletogenesis, may have also played an essential role in the evolution of the larval skeleton. Unlike those echinoderms that have a larval skeleton, we found that alx1 of starfish was barely expressed in early larvae that have no skeleton. When alx1 overexpression was induced via injection of alx1 mRNA into starfish eggs, the expression patterns of certain genes, including those possibly involved in skeletogenesis, were altered. This suggested that a portion of the skeletogenic program was induced solely by alx1. However, we observed no obvious external phenotype or skeleton. We concluded that alx1 was necessary but not sufficient for the acquisition of the larval skeleton, which, in fact, requires several genetic events. Based on these results, we discuss how the larval expression of alx1 contributed to the acquisition of the larval skeleton in the putative ancestral lineage of echinoderms. 相似文献
54.
55.
Elisabet Safont Teresa Vegas-vilarrúbia Valentí Rull Bruce K. Holst Otto Huber Shingo Nozawa 《分类学与生物多样性》2013,11(4):327-344
The Guayana Highlands (GH) constitute a highly diverse, but relatively poorly studied Neotropical biome, comprised of ~50 flat-topped mountain summits (called tepuis). Previous studies based on warming forecasts for the region suggested that an upward displacement of environmental conditions of 500–700 m could occur by 2100, potentially resulting in the extinction of c. 50% of its endemic flora due to total habitat loss. To assess the ecological responses of the species to climate change, and select the appropriate conservation measures, long-term monitoring of the GH plant communities will be necessary. In this study, the baseline state for future comparisons was established for the best explored tepui in terms of its flora, Roraima-tepui (2810 m), through a floristic characterization of its different vegetation types. We also identified the environmental gradients underlying the major plant communities, and assessed the effects of human activities on the chemistry of soils and water at three field camps. Our results yielded five main community types: three meadows, one shrubland, and one forest, with their corresponding diagnostic species. The herbaceous communities were mainly influenced by the presence of flat sandy soils, with varying flooding capacity. Shrublands and forests were characterized by irregular organic soils with very low pH. Finally, pH values below 3 were measured on an organic soil of a field camp, although further studies will be necessary to attribute this deviation to human activities. 相似文献
56.
Yuichi Nozawa Takeji Umemura Satoru Joshita Yoshihiko Katsuyama Soichiro Shibata Takefumi Kimura Susumu Morita Michiharu Komatsu Akihiro Matsumoto Eiji Tanaka Masao Ota 《PloS one》2013,8(12)
Natural killer cell responses play a crucial role in virus clearance by the innate immune system. Although the killer immunoglobulin-like receptor (KIR) in combination with its cognate human leukocyte antigen (HLA) ligand, especially KIR2DL3-HLA-C1, is associated with both treatment-induced and spontaneous clearance of hepatitis C virus (HCV) infection in Caucasians, these innate immunity genes have not been fully clarified in Japanese patients. We therefore investigated 16 KIR genotypes along with HLA-B and -C ligands and a genetic variant of interleukin (IL) 28B (rs8099917) in 115 chronic hepatitis C genotype 1 patients who underwent pegylated-interferon-α2b (PEG-IFN) and ribavirin therapy. HLA-Bw4 was significantly associated with a sustained virological response (SVR) to treatment (P = 0.017; odds ratio [OR] = 2.50, ), as was the centromeric A/A haplotype of KIR (P = 0.015; OR 3.37). In contrast, SVR rates were significantly decreased in patients with KIR2DL2 or KIR2DS2 (P = 0.015; OR = 0.30, and P = 0.025; OR = 0.32, respectively). Multivariate logistic regression analysis subsequently identified the IL28B TT genotype (P = 0.00009; OR = 6.87, 95% confidence interval [CI] = 2.62 - 18.01), KIR2DL2/HLA-C1 (P = 0.014; OR = 0.24, 95% CI = 0.08 - 0.75), KIR3DL1/HLA-Bw4 (P = 0.008, OR = 3.32, 95% CI = 1.37 - 8.05), and white blood cell count at baseline (P = 0.009; OR = 3.32, 95% CI = 1.35 - 8.16) as independent predictive factors of an SVR. We observed a significant association between the combination of IL28B TT genotype and KIR3DL1-HLA-Bw4 in responders (P = 0.0019), whereas IL28B TT along with KIR2DL2-HLA-C1 was related to a non-response (P = 0.0067). In conclusion, combinations of KIR3DL1/HLA-Bw4, KIR2DL2/HLA-C1, and a genetic variant of the IL28B gene are predictive of the response to PEG-IFN and ribavirin therapy in Japanese patients infected with genotype 1b HCV. 相似文献
57.
Felipe Lira Pedro S. Perez José A. Baranauskas Sérgio R. Nozawa 《Applied and environmental microbiology》2013,79(10):3156-3159
Antimicrobial resistance is a persistent problem in the public health sphere. However, recent attempts to find effective substitutes to combat infections have been directed at identifying natural antimicrobial peptides in order to circumvent resistance to commercial antibiotics. This study describes the development of synthetic peptides with antimicrobial activity, created in silico by site-directed mutation modeling using wild-type peptides as scaffolds for these mutations. Fragments of antimicrobial peptides were used for modeling with molecular modeling computational tools. To analyze these peptides, a decision tree model, which indicated the action range of peptides on the types of microorganisms on which they can exercise biological activity, was created. The decision tree model was processed using physicochemistry properties from known antimicrobial peptides available at the Antimicrobial Peptide Database (APD). The two most promising peptides were synthesized, and antimicrobial assays showed inhibitory activity against Gram-positive and Gram-negative bacteria. Colossomin C and colossomin D were the most inhibitory peptides at 5 μg/ml against Staphylococcus aureus and Escherichia coli. The methods described in this work and the results obtained are useful for the identification and development of new compounds with antimicrobial activity through the use of computational tools. 相似文献
58.
The ppGpp-signaling system functions in plant chloroplasts. In bacteria, a negative effect of ppGpp on adenylosuccinate synthetase (AdSS) has been suggested. Our biochemical analysis also revealed rice AdSS homologs are apparently sensitive to ppGpp. However, further investigation clarified that this phenomenon is cancelled by the high substrate affinity to the enzymes, leading to a limited effect of ppGpp on adenylosuccinate synthesis. 相似文献
59.
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60.
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