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1.
Yuji Inaba Yoshio Tanaka Sukemitsu Ishii Tomiaki Morimoto Kunihiko Sato Tuneyoshi Omori Minoru Matumoto 《Microbiology and immunology》1970,14(5):351-360
Replication of Ibaraki virus was not inhibited by 5-iodo-2′-deoxyuridine, indicating that the virus is an RNA virus. The virus was resistant to ether, chloroform and deoxycholate, sensitive to trypsin, very labile at acidic pH but stable at pH 6.4 or higher, and was resistant to repeated freezing and thawing. The virus was readily inactivated at 56 C or higher, was fairly stable at 37 C, and very stable at 4 C, while it rapidly lost infectivity when stored frozen at —20 C. The virus was readily sedimented by centrifugation at 40 000Xg for 60 min. It readily passed through membrane filters of 200 mμ pore size, passed through 100 μfilters but only with some titer loss and did not through 50 mμ filters. In these tests, the bluetongue virus used as a control behaved in the same manner as Ibaraki virus. These findings provide additional evidence for the similarity of Ibaraki virus to bluetongue virus which had been previously demonstrated on the basis of seasonal incidence, symptomatology and pathology of the diseases caused by these viruses and the behavior of the viruses in cell cultures, embryonated eggs and laboratory animals. The present study, however, provided no evidence for any serological relation between these two viruses. More Information is needed to reach a final decision on the classification of Ibaraki virus, particularly regarding the morphology of the virion, the doublestrandedness of the viral RNA and other basic features. 相似文献
2.
3.
Hiroyuki Kozu Isao Kobayashi Mitsutoshi Nakajima Kunihiko Uemura Seigo Sato Sosaku Ichikawa 《Food biophysics》2010,5(4):330-336
This paper uses computational fluid dynamics to simulate and analyze intragastric fluid motions induced by human peristalsis.
We created a two-dimensional computational domain of the distal stomach where peristalsis occurs. The motion of the gastric
walls induced by an antral contraction wave (ACW) on the wall of the computational domain was well simulated using a function
defined in this study. Retropulsive flow caused by ACW was observed near the occluded region, reaching its highest velocity
of approximately 12 mm/s in the narrowest region. The viscosity of the model gastric contents applied in this study hardly
affected the highest velocity, but greatly affected the velocity profile in the computational domain. The shear rate due to
gastric fluid motion was calculated using the numerical output data. The shear rate reached relatively high values of approximately
20 s−1 in the most occluded region. The shear rate profile was almost independent of the fluid viscosity. We also simulated mass
transfer of a gastric digestive enzyme (pepsin) in model gastric content when peristalsis occurs on the gastric walls. The
visualized simulation results suggest that gastric peristalsis is capable of efficiently mixing pepsin secreted from the gastric
walls with an intragastric fluid. 相似文献
4.
NatB is an N-terminal acetyltransferase consisting of a catalytic Nat5 subunit and an auxiliary Mdm20 subunit. In yeast, NatB acetylates N-terminal methionines of proteins during de novo protein synthesis and also regulates actin remodeling through N-terminal acetylation of tropomyosin (Trpm), which stabilizes the actin cytoskeleton by interacting with actin. However, in mammalian cells, the biological functions of the Mdm20 and Nat5 subunits are not well understood. In the present study, we show for the first time that Mdm20-knockdown (KD), but not Nat5-KD, in HEK293 and HeLa cells suppresses not only cell growth, but also cellular motility. Although stress fibers were formed in Mdm20-KD cells, and not in control or Nat5-KD cells, the localization of Trpm did not coincide with the formation of stress fibers in Mdm20-KD cells. Notably, knockdown of Mdm20 reduced the expression of Rictor, an mTORC2 complex component, through post-translational regulation. Additionally, PKCαS657 phosphorylation, which regulates the organization of the actin cytoskeleton, was also reduced in Mdm20-KD cells. Our data also suggest that FoxO1 phosphorylation is regulated by the Mdm20-mTORC2-Akt pathway in response to serum starvation and insulin stimulation. Taken together, the present findings suggest that Mdm20 acts as a novel regulator of Rictor, thereby controlling mTORC2 activity, and leading to the activation of PKCαS657 and FoxO1. 相似文献
5.
Kato Yoji; Otsuki Tatsuya; Nakajima Tasuku; Ojima Kunihiko; Matsuda Kazuo 《Plant & cell physiology》1988,29(4):539-547
-Glucans (average mol wt, 1.3 ? 104) extracted with perchloricacid from 8-day-old suspension-cultured nonglutinous (var. Sasanishiki)and glutinous rice (var. Miyakogane) cells were compared. Theresults of hydrolysis by alpha;-, ß- and iso-amylasesand methylation analysis of the -glucans suggested that theirbasic structures are almost the same. These -glucans are highly-branchedpolysaccharides with an average chain length of about 910,with exterior and interior chain lengths of about 67and 23, respectively.
1Current address: Laboratory of Food Science, Faculty of Education,Hirosaki University, Hirosaki, Aomori 036, Japan. (Received April 27, 1987; Accepted March 2, 1988) 相似文献
6.
Mitsuyasu Hasebe Rumiko Kofuji Motomi Ito Mikio Kato Kunio Iwatsuki Kunihiko Ueda 《Journal of plant research》1992,105(4):673-679
Partial nucleotide sequences of the large subunit of ribulose-1,5-bisphosphate carboxylase (rubisco) gene (1333 base pairs:
about 90% of the gene) from several seed plants were determined. Phylogenetic trees based on amino acid sequences were inferred
by using the neighbor joining and maximum likelihood methods. The results indicate (1) monophyly of gnetum group (Ephedra, Gnetum, Welwitschia), (2) monophyly of extant gymnosperms containing gnetum group, which contradicts the results of morphological data. 相似文献
7.
Compressibility-structure relationship of globular proteins 总被引:16,自引:0,他引:16
The adiabatic compressibility, -beta s, of 11 globular proteins in water was determined by means of sound velocity measurements at 25 degrees C. All the proteins studied except for subtilisin showed positive -beta s values, indicating the large internal compressibility of the protein molecules. The intrinsic compressibility of proteins free from the hydration effect appeared to be comparable to that of normal ice. The compressibility data for 25 proteins, including 14 reported previously [Gekko, K., & Noguchi, H. (1979) J. Phys. Chem. 83, 2706-2714], were statistically analyzed to examine the correlation of the compressibility with some structural parameters and the amino acid compositions of proteins. It was found that -beta s increases with increasing partial specific volume and hydrophobicity of proteins. The helix element also seemed to be a dynamic domain to increase -beta s. Four amino acid residues (Leu, Glu, Phe, and His) greatly increased -beta s, and another four (Asn, Gly, Ser, and Thr) decreased it. Some empirical equations were derived for the estimation of the -beta s values of unknown proteins on the basis of their amino acid compositions. The volume fluctuations of proteins revealed by the compressibility data were in the range of 30-200 mL/mol, which corresponded to about 0.3% of the total protein volume. The conformational fluctuation seemed to enhance the thermal stability of proteins. 相似文献
8.
The toxic effect of aluminum (Al) on the growth of Carrot cells(SO-l) decreased to a greater degree with addition of a mediumconditioned by Al-tolerant carrot cells (TA-l) than with a mediumconditioned by SO-l cells. The toxic effect of Al was reducedgreatly by adding an acidic fraction of the conditioned media,but little or not at all by a neutral or basic fraction. Offour organic acids detected in the acidic fraction, the majorone was citric acid which was present in a much greater amountin the conditioned medium of TA-l cells than in that of SO-lcells. The toxic effect of Al was reduced by adding citric or malicacid instead of the conditioned medium, but not by succinicor fumaric acid. Chelating abilities of the organic acids wereevaluated by shifts in their titration curves, and were foundto be closely correlated with the detoxification effects. Thus,the Al tolerance of TA-l cells may in fact be due to the chelatingeffect of citric acid which is abundantly released into themedium by the Al-tolerant carrot cells. (Received July 9, 1984; Accepted November 22, 1984) 相似文献
9.
Journal of Plant Research - The vascular anatomy of seven genera of Magnoliaceae:Elmerrillia, Liriodendron, Magnolia, Manglietia, Michelia, Paramichelia andTalauma, was examined. Based on the... 相似文献
10.
Benzyladenine (BA) stimulated division but not expansion ofmesophyll cells and repressed chlorophyll accumulation in attachedyoung bean leaves. Even in the presence of fluorodeoxyuridine(FUdR) or mitomycin C which causes complete suppression of BA-inducedincrease in DNA content, BA increased RNA and protein contentsand fresh weight, but decreased chlorophyll accumulation. Moreover,BA n the presence of FUdR induced marked cell expansion. Inthe presence of a-amanitin (AM), BA did not produce any changein DNA content, fresh weight or cell size. All of the BA effectswere observed even in the presence of fluorouracil (FU) plusthymidine (TdR). AM and cycloheximide added 012 h effectively inhibitedBA-stimulated cell division but showed no effect if added at18 h. FU plus TdR added 018 h had almostno effect onthe cell number at 24 h. These results indicate that BA stimulates the mRNA synthesisnecessary for induction of cell division, and that the synthesisof cytoplasmic rRNA is not always necessary for BA-stimulatedcell division, and moreover, that BA stimulates expansion growthof cells in which DNA synthesis is suppressed. (Received August 16, 1982; Accepted March 31, 1983) 相似文献