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21.
This study proposes a vision model for individual colorimetric observers. The proposed model can be beneficial in many color-critical applications such as color grading and soft proofing to assess ranges of color matches instead of a single average match. We extended the CIE 2006 physiological observer by adding eight additional physiological parameters to model individual color-normal observers. These eight parameters control lens pigment density, macular pigment density, optical densities of L-, M-, and S-cone photopigments, and λmax shifts of L-, M-, and S-cone photopigments. By identifying the variability of each physiological parameter, the model can simulate color matching functions among color-normal populations using Monte Carlo simulation. The variabilities of the eight parameters were identified through two steps. In the first step, extensive reviews of past studies were performed for each of the eight physiological parameters. In the second step, the obtained variabilities were scaled to fit a color matching dataset. The model was validated using three different datasets: traditional color matching, applied color matching, and Rayleigh matches. 相似文献
22.
Masahiro Nakajima Ryuta Yoshida Akimasa Miyanaga Koichi Abe Yuta Takahashi Naohisa Sugimoto Hiroyuki Toyoizumi Hiroyuki Nakai Motomitsu Kitaoka Hayao Taguchi 《PloS one》2016,11(2)
Despite the presence of β-1,2-glucan in nature, few β-1,2-glucan degrading enzymes have been reported to date. Recently, the Lin1839 protein from Listeria innocua was identified as a 1,2-β-oligoglucan phosphorylase. Since the adjacent lin1840 gene in the gene cluster encodes a putative glycoside hydrolase family 3 β-glucosidase, we hypothesized that Lin1840 is also involved in β-1,2-glucan dissimilation. Here we report the functional and structural analysis of Lin1840. A recombinant Lin1840 protein (Lin1840r) showed the highest hydrolytic activity toward sophorose (Glc-β-1,2-Glc) among β-1,2-glucooligosaccharides, suggesting that Lin1840 is a β-glucosidase involved in sophorose degradation. The enzyme also rapidly hydrolyzed laminaribiose (β-1,3), but not cellobiose (β-1,4) or gentiobiose (β-1,6) among β-linked gluco-disaccharides. We determined the crystal structures of Lin1840r in complexes with sophorose and laminaribiose as productive binding forms. In these structures, Arg572 forms many hydrogen bonds with sophorose and laminaribiose at subsite +1, which seems to be a key factor for substrate selectivity. The opposite side of subsite +1 from Arg572 is connected to a large empty space appearing to be subsite +2 for the binding of sophorotriose (Glc-β-1,2-Glc-β-1,2-Glc) in spite of the higher Km value for sophorotriose than that for sophorose. The conformations of sophorose and laminaribiose are almost the same on the Arg572 side but differ on the subsite +2 side that provides no interaction with a substrate. Therefore, Lin1840r is unable to distinguish between sophorose and laminaribiose as substrates. These results provide the first mechanistic insights into β-1,2-glucooligosaccharide recognition by β-glucosidase. 相似文献
23.
Yumiko Chiba Tetsuya Yamada Sohei Tsukita Kei Takahashi Yuichiro Munakata Yuta Shirai Shinjiro Kodama Yoichiro Asai Takashi Sugisawa Kenji Uno Shojiro Sawada Junta Imai Kazuhiro Nakamura Hideki Katagiri 《PloS one》2016,11(3)
Selective sodium glucose cotransporter-2 inhibitor (SGLT2i) treatment promotes urinary glucose excretion, thereby reducing blood glucose as well as body weight. However, only limited body weight reductions are achieved with SGLT2i treatment. Hyperphagia is reportedly one of the causes of this limited weight loss. However, the effects of SGLT2i treatment on systemic energy expenditure have not been fully elucidated. Herein, we investigated the acute effects of dapagliflozin, a SGLT2i, on systemic energy expenditure in mice. Eighteen hours after dapagliflozin treatment oxygen consumption and brown adipose tissue (BAT) expression of ucp1, a thermogenesis-related gene, were significantly decreased as compared to those after vehicle treatment. In addition, dapagliflozin significantly suppressed norepinephrine (NE) turnover in BAT and c-fos expression in the rostral raphe pallidus nucleus (rRPa) which contains the sympathetic premotor neurons responsible for thermogenesis. These findings indicate that the dapagliflozin-mediated acute decrease in energy expenditure involves a reduction in BAT thermogenesis via decreased sympathetic nerve activity from the rRPa. Furthermore, common hepatic branch vagotomy abolished the reductions in ucp1 expression and NE contents in BAT and c-fos expression in the rRPa. In addition, alterations in hepatic carbohydrate metabolism, such as decreases in glycogen contents and upregulation of phosphoenolpyruvate carboxykinase, manifested prior to the suppression of BAT thermogenesis, e.g. 6 hours after dapagliflozin treatment. Collectively, these results suggest that SGLT2i treatment acutely suppresses energy expenditure in BAT via regulation of an inter-organ neural network consisting of the common hepatic vagal branch and sympathetic nerves. 相似文献
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26.
Akie Kobayashi Hye‐Jeong Kim Yuta Tomita Yutaka Miyazawa Nobuharu Fujii Sachiko Yano Chiaki Yamazaki Motoshi Kamada Haruo Kasahara Sachiko Miyabayashi Toru Shimazu Yasuo Fusejima Hideyuki Takahashi 《Physiologia plantarum》2019,165(3):464-475
Plants exhibit helical growth movements known as circumnutation in growing organs. Some studies indicate that circumnutation involves the gravitropic response, but this notion is a matter of debate. Here, using the agravitropic rice mutant lazy1 and space‐grown rice seedlings, we found that circumnutation was reduced or lost during agravitropic growth in coleoptiles. Coleoptiles of wild‐type rice exhibited circumnutation in the dark, with vigorous oscillatory movements during their growth. The gravitropic responses in lazy1 coleoptiles differed depending on the growth stage, with gravitropic responses detected during early growth and agravitropism during later growth. The nutation‐like movements observed in lazy1 coleoptiles at the early stage of growth were no longer detected with the disappearance of the gravitropic response. To verify the relationship between circumnutation and gravitropic responses in rice coleoptiles, we conducted spaceflight experiments in plants under microgravity conditions on the International Space Station. Wild‐type rice seeds were germinated, and the resulting seedlings were grown under microgravity or a centrifuge‐generated 1 g environment in space. We began filming the seedlings 2 days after seed imbibition and obtained images of seedling growth every 15 min. The seed germination rate in space was 92–100% under both microgravity and 1 g conditions. LED‐synchronized flashlight photography induced an attenuation of coleoptile growth and circumnutational movement due to cumulative light exposure. Nevertheless, wild‐type rice coleoptiles still showed circumnutational oscillations under 1 g but not microgravity conditions. These results support the idea that the gravitropic response is involved in plant circumnutation. 相似文献
27.
A simple chiral analysis of amino acid esters by fluorine‐19 nuclear magnetic resonance (19F NMR) through the modified James–Bull method is described. Thus, amino acid ester acid salt was treated with 5‐fluoro‐2‐formylphenylboronic acid and (S)‐BINOL in the presence of triethylamine (TEA) and MS4A for 10 minutes. The reaction mixture was analysed by 19F NMR directly to afford good quantifications. 相似文献
28.
Tatsuo Kawarasaki Masaru Sone Mitsutoshi Yoshida Kimio Bamba 《Molecular reproduction and development》1996,43(4):548-553
This study was carried out to develop a rapid and simultaneous detection system of chromosome Y- and 1-bearing porcine spermatozoa by fluorescence in situ hybridization (FISH). Chromosome Y- and 1-specific DNA probes were produced by polymerase chain reaction with digoxigenin (Dig)- or biotin-dUTP. The hybridization probe mixture of labeled Y-chromosome and chromosome 1-specific DNA was applied to the preparation, immediately denatured at 75°C for 8 min, hybridized for 5 min at 37°C and overall FISH steps were done within a few hours. When double FISH with Dig-labeled chromosome Y-specific and biotin-labeled chromosome 1-specific probes was applied to sperm nuclei pretreated with dithiothreitol, the average of 50.9% of sperm nuclei had the Dig-signal, 99.2% of the sperm nuclei had the biotin-signal and the average of 0.3% of sperm nuclei showed no signal. The putative rate of Y-bearing spermatozoa ranged from 49.8% to 52.8% among 5 boars and the average putative rate of Y-bearing spermatozoa was 51.0%. The results indicated that a rapid and simultaneous FISH with chromosome Y- and 1-specific porcine DNA probes produced by PCR made possible more accurate assessment of Y-bearing porcine spermatozoa. © 1996 Wiley-Liss, Inc. 相似文献
29.
Kaori Tsutsumi Ayaka Chiba Yuta Tadaki Shima Minaki Takahito Ooshima Haruka Takahashi 《Current issues in molecular biology》2021,43(3):1203
Non-small cell lung cancer (NSCLC) is an aggressive lung cancer accounting for approximately 85% of all lung cancer patients. For the patients with Stages IIIA, IIIB, and IIIC, the 5-year survival is low though with the combination with radiotherapy and chemotherapy. In addition, the occurrence of tumor cells (repopulated tumors) that survive irradiation remains a challenge. In our previous report, we subcloned the radiation-surviving tumor cells (IR cells) using the human NSCLC cell line, H1299, and found that the expression of neuropilin-1 (NRP-1) was upregulated in IR cells by the microarray analysis. Here, we investigated the contribution of neuropilin-1 to changes in the characteristics of IR cells. Although there were no differences in angiogenic activity in the tube formation assay between parental and IR cells, the cell motility was increased in IR cells compared to parental cells in the cell migration assay. This enhanced cell motility was suppressed by pretreatment with anti-NRP-1 antibody. Although further studies are necessary to identify other molecules associated with NRP-1, the increase in cellular motility in IR cells might be due to the contribution of NRP-1. Inhibition of NRP-1 would help control tumor malignancy in radiation-surviving NSCLC. 相似文献
30.
The Dam1 complex, also known as DASH complex, is the outer kinetochore protein complex of yeast that plays a crucial role in attachment of kinetochore to microtubule. The Dam1 complex is formed by at least nine proteins including Dam1p, Duo1p, Dad1p, Spc19p and Spc34p. In this study, domains of Spc34p that physically interact with other subunits of the complex were mapped using a high-throughput methodology. The method is a combination of two-hybrid screening of a random truncation library of the Spc34 gene and a unique PCR-based amplification that converge the selected DNA fragments to a few short fragments. Duo1p, Dam1p, Dad1p and Spc19p binding domains of Spc34p were mapped on M1-E59, M1-D47, M1-D47 or T207-E295 and S154-Q294, respectively. Most of the boundaries were located at less conserved regions among fungal Spc34p homologs, which is consistent with the boundaries of the putative secondary structures. The accuracy of the mapped domain boundaries was verified using truncated Spc34p polypeptides. The results and methodology we demonstrated herein not only shed light on the molecular architecture of the protein complex but also pave the road to the high-throughput identification of specific interaction domains of proteins whose possible interaction partners have been identified in genome-scale analyses. 相似文献