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1.
Michinari Hamaguchi Koichiro Maeno Yoshiyuki Nagai Masao Iinuma Tetsuya Yoshida Toshisada Matsumoto 《Microbiology and immunology》1980,24(1):51-63
When p-fluorophenylalanine (FPA) was added to influenza virus RI/5+-infected cells 4 hr after infection, virus-specific proteins were synthesized but infectious progeny virus was not produced. In these cells, synthesis of viral RNA was strongly inhibited and nucleoprotein (NP) antigen was found predominantly in the nucleus in contrast to untreated cells in which NP antigen was distributed throughout the whole cell. The intracellular location and migration of NP were examined by isotope labeling followed by fractionation of infected cells. In untreated cells, a large portion of the NP was present in the cytoplasm and most of it was detected in the form of ribonucleoprotein (RNP). In contrast, in FPA-treated cells little viral RNP was detectable and NP was present predominantly in the nucleus in a nonassembled, soluble form. When FPA was removed from the culture, synthesis of viral RNA was soon restored and a large amount of viral RNP appeared in the cytoplasm; this was followed by the production of infectious virus. The results of the experiments suggest that the NP synthesized in the presence of FPA is not assembled into viral RNP because of the lack of available RNA, and such NP migrates readily into the nucleus and accumulates there. 相似文献
2.
3.
In several vascular inflammatory reactions (i.e. immunity and thrombosis) inflammatory mediators lead to the activation of vascular endothelial cells (EC). To date, a number
of functional molecules induced on the surface of activated-EC have been identified. We report here that Globotetraosylceramide
(Gb4), a glycosphingolipid expressed in EC, is a novel inducible molecule on EC activated by TNF-α. The cell surface expression
of Gb4 is increased in a time-dependent manner under TNF-α stimulation, which shows distinct expression kinetics of major
proteins induced by TNF-α on EC. MALDI-TOF-MS analysis revealed that the enhanced Gb4 predominantly contains C24:0 fatty acid
in the ceramide moiety. Isolated caveolae/lipid raft-enriched detergent insoluble membrane domains in activated-EC predominantly
contain this molecular species of Gb4. Gb4 containing C16:0 fatty acid in the ceramide moiety, which is known to constitute
the major species of Gb4 in plasma, is also found as a major molecular species in EC. These observations indicate that Gb4,
especially with very long fatty acid, is enhanced in EC during its inflammatory reaction, and suggest the potential utility
of Gb4 as a biomarker for monitoring inflammation status of EC involving its related diseases. 相似文献
4.
5.
M. L. Farman S. Taura S. A. Leong S. A. Leong 《Molecular & general genetics : MGG》1996,251(6):675-681
TheMagnaporthe grisea repeat (MGR) sequence MGR586 has been widely used for population studies of the rice blast fungus, and has enabled classification of the fungal population into hundreds of genetic lineages. While studying the distribution of MGR586 sequences in strains ofM. grisea, we discovered that the plasmid probe pCB586 contains a significant amount of single-copy DNA. To define precisely the boundary of the repetitive DNA in pCB586, this plasmid and four cosmid clones containing MGR586 were sequenced. Only 740 bp of one end of the 2.6-bp insert in the pCB586 plasmid was common to all clones. DNA sequence analysis of cosmid DNA revealed that all the cosmids contained common sequences beyond the cloning site in pCB586, indicating that the repetitive DNA in the fingerprinting clone is part of a larger element. The entire repetitive element was sequenced and found to resemble an inverted repeat transposon. This putative transposon is 1.86 kb in length and has perfect terminal repeats of 42 bp, which themselves contain direct repeats of 16 bp. The internal region of the transposon possesses one open reading frame which shows similarity at the peptide level to the Pot2 transposon fromM. grisea and Fot1 fromFusarium oxysporum. Hybridization studies using the entire element as a probe revealed that some strains ofM. grisea, whose DNA hybridized to the pCB586 probe, entirely lacked MGR586 transposon sequences. 相似文献
6.
We previously demonstrated that tumor necrosis factor-α (TNF-α) induces rapid human neutrophil apoptosis. In this paper, we examined which of the TNF receptors, p55 kDa TNF receptor (55-R) or p75 kDa TNF receptor (75-R), or both are involved in this process using specific rabbit antisera. Antibodies to 55-R (anti55-R) or 75-R (anti75-R) alone did not induce neutrophil apoptosis. Further addition of cycloheximide and anti-rabbit immunoglobulin to anti55-R but not to anti75-R accelerated apoptosis, although anti75-R augmented the capacity of anti55-R to do so. These results suggest that 55-R is a prerequisite for TNF-α induced neutrophil apoptosis. 相似文献
7.
Efficiency of serum copper/zinc ratio for differential diagnosis of patients with and without lung cancer 总被引:1,自引:0,他引:1
Tsunehiro Oyama Koji Matsuno Toshihiro Kawamoto Tetsuya Mitsudomi Takayuki Shirakusa Yasushi Kodama 《Biological trace element research》1994,42(2):115-127
We examined serum copper (Cu), serum zinc (Zn), and the serum copper/zinc ratio (Cu/Zn) in 162 patients. All of them were
seen to have an abnormal shadow in the chest X-ray films, that is, 109 patients with lung cancer (LC) and 53 patients with
no lung cancer (NLC). The mean Cu and Cu/Zn in LC patients were significantly higher than those in NLC patients (p<0.05). In LC patients, Cu and Cu/Zn were higher and Zn was lower in advanced tumors than early ones. There was a significantly
clear relation between Cu or Cu/Zn and the tumor (T) stages. When the relative risk (RR) of LC was estimated, it was seen
that the higher Cu and Cu/Zn became, the higher RR became. Furthermore, we showed the sensitivity of the receiver operator
characteristic of the test (ROC) curve for Cu, Cu/Zn, and carcinoembryonic antigen (CEA) to diagnose LC, as explained in a
paragraph of methods.The determinations of Cu, Zn, and Cu/Zn are simple and inexpensive. They also appear to have a great diagnostic value in determining the local invasion of LC and as a screening test in the
high-risk patients for LC. 相似文献
8.
Tetsuya Matsumoto Mitsuo Kaku Kazuhiro Tateda Nobuhiko Furuya Yoichi Hirakata Keizo Yamaguchi 《Microbiology and immunology》1994,38(4):287-293
We evaluated antibody-coated bacteria (ACB) in expectorated sputum to discriminate contaminating or colonizing organisms from true pathogens. We examined 60 expectorated sputum samples from 51 patients with lower respiratory infections (chronic obstructive pulmonary disease 25, pneumonia 20, purulent tracheobronchitis 6). All samples were examined with quantitative culture and immunofluorescent demonstration of ACB. From the results of quantitative culture, we divided specimens into pathogen-isolated and pathogen-free samples. Among pathogen-isolated samples, in which we isolated accepted pathogenic organisms at ≥ 107 colony-forming units per ml, 16 of 23 samples were ACB-positive (69.5%). In contrast, among pathogen-free samples, in which we isolated accepted pathogens at < 107 colony forming units per ml or only upper respiratory flora, only 3 of 37 samples were ACB-positive (8.1%). The ACB-positive rate was significantly higher in pathogen-isolated than in pathogen-free samples (P < 0.001). Consequently, detecting ACB in expectorated sputum shows good potential as another criterion for distinguishing contaminating or colonizing organisms from true pathogens. 相似文献
9.
Kimura Tetsuya; Takeda Shin; Kyozuka Junko; Asahi Tadashi; Shimamoto Ko; Nakamura Kenzo 《Plant & cell physiology》1993,34(2):345-355
A precursor to the 相似文献
10.
Tetsuya Oguma Asahi Matsuyama Mamoru Kikuchi Eiichi Nakano 《Applied microbiology and biotechnology》1993,39(2):197-203
The gene for cyclomaltodextrinase (CDase; EC 3.2.1.54) from Bacillus sphaericus E-244 was cloned in the recombinant plasmid pCD629. Sequencing a portion of pCD629 revealed a unique open reading frame of 1,773 nucleotides coding for a 591-amino-acid polypeptide. The deduced polypeptide sequence showed about 50% homology with that of a neopullulanase, and was slightly homologous to those of the cyclodextrin glucanotransferases and the -amylases. The optimum pH, specific activity and K
m value for -cyclodextrin of the CDase that has been produced in Escherichia coli cells were 8.0, 16.4 units/mg protein, and 0.41 mm, respectively. These values were almost identical to those from B. sphaericus E-244.
Correspondence to: T. Oguma 相似文献