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11.
12.
Tsunehiro Aki Kazutaka Hachida Megumi Yoshinaga Yuko Katai Takashi Yamasaki Seiji Kawamoto Toshihide Kakizono Takashi Maoka Seiko Shigeta Osamu Suzuki Kazuhisa Ono 《Journal of the American Oil Chemists' Society》2003,80(8):789-794
Thraustochytrids, marine protists whose dominant genera are Thraustochytrium and Schizochytrium, belong to the kingdom Chromista and are known as an industrial source of DHA. We describe here that thraustochytrid strain
KH105, isolated as a DHA producer, also accumulates significant levels of β-carotene and xanthophylls including canthaxanthin
and astaxanthin. A4-d cultivation using a medium composed of 10% glucose and less than 0.3% of nitrogen sources in a half-concentration
of seawater gave an astaxanthin production up to 6.1 mg/L, and canthaxanthin content reached more than 10 mg/L under conditions
where a higher concentration of nitrogen sources (6%) was employed. It might be advantageous in mass production systems for
these carotenoids to be extracted readily by simply suspending the cells with organic solvents such as acetone and chloroform.
Analyses on the morphological and life history features of the KH105 strain revealed that it belongs to the genus Schizochytrium. This particular species of thraustochytrids is thus considered to be a promising source of xanthophylls as well as DHA for
use in the food industry. 相似文献
13.
Kazuko Yamasaki Kenneth J. Mackin Masanori Ohshiro Kotaro Matsushita Eiji Nunohiro 《Artificial Life and Robotics》2008,12(1-2):122-124
We studied the networks of the temperature record in the atmosphere. They are made by the strength of the synchronization,
including the delay between temperatures at locations on Earth. We consider these locations as nodes, and we consider a pair
of locations as a link if the synchronization between them is stronger than a threshold. The network is scale-free, which
is thought to contribute to the stability of the climate.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
14.
H. Takahashi L. H. Liu Y. Yashiro K. Ioku G. Bignall N. Yamasaki T. Kori 《Journal of Materials Science》2006,41(5):1585-1589
The reduction of CO2 under hydrothermal conditions has been investigated. In typical experiment, Fe-powder, Ni-powder, solvent, and CO2 have been reacted in a batch-type micro autoclave under hydrothermal conditions for several hours. Methane, formic acid,
and hydrogen were generated after treatment in water. With the rise of Ni amount, the methane yield increased while hydrogen
and formic acid decreased. It is supposed that Ni has acted as a hydrogenation catalyst. In basic solution, CO2 was converted to formic acid selectively at 300°C involved with trace of methane. Considering the reduction characteristics
of formic acid, the reaction pathway has been discussed. In experiments with the mixture of Fe and Fe3O4, trace of methanol was detected at the experiments with less amount of metallic Fe. It is inferred that the control on the
effect of reductant is indispensable for oxygenated organic compound formation. Experiment on the effect of water has been
conducted using hydrogen. Ethane yield increased with the amount of water, while there was no drastic change in the yield
of methane. From these results, it is supposed that the steam reforming reaction of methane was involved in the reduction
of CO2, and effected on the C–C bond formation. 相似文献
15.
Z. Jing N. Matsuoka F. Jin N. Yamasaki K. Suzuki T. Hashida 《Journal of Materials Science》2006,41(5):1579-1584
Solidification of Coal Fly-ash (CFA) has been carried out using a hydrothermal processing method. In the hydrothermal processing,
the CFA was first compacted in a mold at 20 - 50 MPa, and then hydrothermally cured in an autoclave. The hydrothermal curing
was performed at 150 – 250°C for 15 – 60 h. The experimental results showed that NaOH solution, Ca(OH)2 content, compaction pressure, autoclave curing temperature and time significantly affected the strength of solidified bodies.
The most important strength-producing constituent in the solidified bodies produced with CFA was tobermorite, or tobermorite-like
calcium silicate hydrate. When the CaO/SiO2 ratio of the starting material was close to 0.83, tobermorite readily formed and the formed tobermorite enhanced the strength
of solidified bodies. The tensile strength determined by the Brazilian test reached more than 10 MPa under the hydrothermal
processing. As such, the hydrothermal processing method may provide a high potential for recycling CFA on a large scale. 相似文献
16.
Tomohiro Fujii Jun Nishikawa Soichiro Fukuda Naoto Kubota Junzo Nojima Koichi Fujisawa Ryo Ogawa Atsushi Goto Koichi Hamabe Shinichi Hashimoto Aung Phyo Wai Hisashi Iizasa Hironori Yoshiyama Kohei Sakai Yutaka Suehiro Takahiro Yamasaki Taro Takami 《International journal of molecular sciences》2022,23(18)
DNA methylation of both viral and host DNA is one of the major mechanisms involved in the development of Epstein–Barr virus-associated gastric carcinoma (EBVaGC); thus, epigenetic treatment using demethylating agents would seem to be promising. We have verified the effect of , which was discovered by screening for demethylating agents. MC180295 inhibited cell growth of the EBVaGC cell lines YCCEL1 and SNU719 in a dose-dependent manner. In a cell cycle analysis, growth arrest and apoptosis were observed in both YCCEL1 and SNU719 cells treated with MC180295. MKN28 cells infected with EBV were sensitive to MC180295 and showed more significant inhibition of cell growth compared to controls without EBV infection. Serial analysis of gene expression analysis showed the expression of genes belonging to the role of BRCA1 in DNA damage response and cell cycle control chromosomal replication to be significantly reduced after MC180295 treatment. We confirmed with quantitative PCR that the expression levels of BRCA2, FANCM, RAD51, TOP2A, and CDC45 were significantly decreased by MC180295. LMP1 and BZLF1 are EBV genes with expression that is epigenetically regulated, and MC180295 could up-regulate their expression. In conclusion, MC180295 inhibited the growth of EBVaGC cells by suppressing DNA repair and the cell cycle. MC180295相似文献
17.
18.
Narisawa N Furukawa S Kawarai T Ohishi K Kanda S Kimijima K Negishi S Ogihara H Yamasaki M 《International journal of food microbiology》2008,124(1):103-107
We investigated the effects of skimmed milk and its protein fractions (casein, whey, globulin, and albumin) on the injury and inactivation of Escherichia coli K-12 by high hydrostatic pressure (HHP) treatment. The protective effect of skimmed milk on HHP-mediated inactivation and injury of E. coli increased with increases in the skimmed milk concentration. However, protein fractions derived from skimmed milk did not exhibit this protective effect. Microscopy analysis by DAPI/PI staining indicated that some cells were localized in the solid portion of skimmed milk, and some of these cells were alive. The coagulated fraction derived from the autoclaved whey fraction also showed a significant protective effect. We speculate that the solid portion in skimmed milk could provide the protective effect to bacterial cells. 相似文献
19.
Automated Synthesis of (rac)‐, (R)‐, and (S)‐[18F]Epifluorohydrin and Their Application for Developing PET Radiotracers Containing a 3‐[18F]Fluoro‐2‐hydroxypropyl Moiety 下载免费PDF全文
Dr. Tomoteru Yamasaki Yiding Zhang Wakana Mori Dr. Masayuki Hanyu Katsushi Kumata Akiko Hatori Dr. Lin Xie Nobuki Nengaki Prof. Dr. Ming‐Rong Zhang 《ChemMedChem》2018,13(16):1723-1731
To introduce the 3‐[18F]fluoro‐2‐hydroxypropyl moiety into positron emission tomography (PET) radiotracers, we performed automated synthesis of (rac)‐, (R)‐, and (S)‐[18F]epifluorohydrin ([18F] 1 ) by nucleophilic displacement of (rac)‐, (R)‐, or (S)‐glycidyl tosylate with 18F? and purification by distillation. The ring‐opening reaction of (R)‐ or (S)‐[18F] 1 with phenol precursors gave enantioenriched [18F]fluoroalkylated products without racemisation. We then synthesised (rac)‐, (R)‐, and (S)‐ 2‐{5‐[4‐(3‐[18F]fluoro‐2‐hydroxypropoxy)phenyl]‐2‐oxobenzo[d]oxazol‐3(2H)‐yl}‐N‐methyl‐N‐phenylacetamide ([18F] 6 ) as novel radiotracers for the PET imaging of translocator protein (18 kDa) and showed that (R)‐ and (S)‐[18F] 6 had different radioactivity uptake in mouse bone and liver. Thus, (rac)‐, (R)‐, and (S)‐[18F] 1 are effective radiolabelling reagents and can be used to develop PET radiotracers by examining the effects of chirality on their in vitro binding affinities and in vivo behaviour. 相似文献
20.
Sang Jun Yoon Jae Goo Lee Hideo Tajima Akihiro Yamasaki Fumio Kiyono Tetsuya Nakazato Hiroaki Tao 《Journal of Industrial and Engineering Chemistry》2010,16(3):350-354
Extractions of five kinds of lanthanide metal ions by bis(2-ethylhexyl)phosphoric acid (DEHPA) with [1-Cn-3-methylimidazolium][PF6](Cn = C2, C4) or [1-butyl-4-methylpyridinium][PF6] were carried out under various DEHPA and HNO3 concentrations from 0 to 1 M and under different temperature conditions from 298 to 333 K. These results were compared with those using the conventional organic solvent, hexane, in terms of their distribution coefficient values. Under all of the conditions in this study, the ionic liquid system shows more than three times greater extractability for lanthanide compared to when hexane was used. The distribution coefficient of lanthanide ions decreased as the length of the alkyl chain increased from the ethyl to the butyl. In addition, the imidazolium cation generally shows a higher distribution coefficient compared to the pyridinium cation in an ionic liquid. The concentration ratio of lanthanides and DEHPA resulted in an extraction affinity transition for lanthanides. Also evaluated in this study were issues related to the selectivity associated with the lanthanide mixture and the dependency of the ionic radius during lanthanide extraction. 相似文献