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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.
Inhibition of cathepsin L-induced degradation of epidermal growth factor receptors by c-Ha-ras gene products 总被引:1,自引:0,他引:1
T Hiwasa S Sakiyama S Yokoyama J M Ha J Fujita S Noguchi Y Bando E Kominami N Katunuma 《Biochemical and biophysical research communications》1988,151(1):78-85
The inhibitory activities of c-Ha-ras gene products (p21s) toward several cysteine proteinases have been investigated. The activity of cathepsin L was inhibited by p21s most effectively while those of cathepsin B and papain were slightly inhibited by p21s. p21s did not show any inhibitory activity toward cathepsin H. In order to connect the protease-inhibitor activity of p21s with cell growth, the degradation of epidermal growth factor receptors (EGF-receptors) was investigated. EGF-receptors were preferentially cleaved by cathepsin L but not by cathepsin B or H. The cleavage of EGF-receptors by cathepsin L was inhibited by p21s dose-dependently. These results raise the possibility that p21s can suppress the degradation of growth-related proteins such as EGF-receptors and thereby affect cell growth. 相似文献
6.
K Ii K Hizawa E Kominami Y Bando N Katunuma 《The journal of histochemistry and cytochemistry》1985,33(11):1173-1175
Different localizations of cathepsin B, H, and L in normal rat liver were revealed immunohistochemically with anticathepsin Fab'-horseradish peroxidase conjugates. Staining of cathepsin B was strong in the periportal sinusoids, possibly in Kupffer cells; and weaker in panlobular hepatocytes. Staining of cathepsin H was strong in panlobular hepatocytes, especially in the periphery of the cytoplasm, possibly representing the peribiliary dense bodies; and weaker in periportal sinusoidal cells, possibly Kupffer cells. Staining of cathepsin L was strongest in centrilobular hepatocytes and weaker in periportal sinusoidal cells, possibly Kupffer cells. These findings, revealed for the first time in the present study, show that the histologic and intracellular localizations of the three cathepsins are different, suggesting that they have different roles in degradation of exogenous and endogenous proteins. 相似文献
7.
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
8.
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
9.
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
10.
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