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81.
When chicken erythrocytes (CRBC) were pretreated with non-haemolytic Sendai virions or isolated HANA spikes, they acquired a resistance to the haemolytic action of "second challenge" viruses. This resistance was dependent on the quantity of N-acetylneuraminic acid liberated from the surface of the CRBC by the initial virus, and not on the use of different viral sources. When exposed to Sendai virus, CRBC were more difficult to be lysed and easier liberated N-acetylneuraminic acid than human 0 erythrocytes. The restricted number of virions able to fuse CRBC was explained by such neuraminidase function of the HANA spike of the virion. 相似文献
82.
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84.
Khan MH Yasuda M Higashino F Haque S Kohgo T Nakamura M Shindoh M 《The American journal of pathology》2001,158(5):1785-1791
nm23-H1 is a candidate gene for the suppression of cancer metastasis. Several studies on human breast, hepatocellular, gastric, ovarian, and colon carcinomas and melanomas have shown that reduced nm23-H1 expression was closely related to metastatic progression with poor prognosis. However, the biochemical mechanism by which nm23-H1 suppresses the metastasis has yet to be elucidated. In this study, we analyzed the correlation between nm23 expression, cell motility, and the invasive abilities of six different oral squamous cell carcinoma cell lines (HSC2, HSC3, HSC4, KB, OSC19, and OSC20). Reduced mRNA/protein expression of the nm23-H1 was observed in three cell lines (HSC2, HSC3, and HSC4). These cell lines exhibited increased cell motility and an invasive character on organotypic raft culture. On the other hand, the cell lines (KB, OSC19, and OSC20) that showed a higher expression of nm23-H1 exhibited a threefold to fivefold reduced motility and also reflected fewer invasions compared to the former three cell lines. Because the HSC3 cells demonstrated the lowest nm23-H1 expression with the highest cell motility and invasive character, we established nm23-H1-transfected HSC3 cell lines to investigate whether exogenous nm23-H1 protein could inhibit cell migration and invasive activity. These transfectants showed a significant reduction in cell motility with exogenous nm23-H1 in a dose-dependent manner, and exhibited a noninvasive character. An immunofluorescence study demonstrated a distinct stress-fiber distribution at peripheral region of these transfectants. However, no significant difference of matrix metalloproteinase (MMP)-2 and MMP-9 expression was observed between mock transfectant and nm23-H1-transfected cells. These findings suggest that nm23-H1 inhibits the invasive activity of oral squamous cell carcinoma by suppression of cell motility without altering the MMP-2 and MMP-9 status. 相似文献
85.
An autopsy case of a 65-year-old male who died of hepatocellular carcinoma superimposed on liver cirrhosis complicated with systemic sarcoidosis is presented. No organ metastasis of hepatocellular carcinoma was found except for a minute tumor embolus in the left upper lobe of the lung. Involved organs by sarcoidosis were the lymph nodes, lungs, heart, liver and spleen, but its presence was not noticed before death. Its cardiac involvement coincide with his clinical symptom of exertional dyspnea and the ECG finding of A-V block. 相似文献
86.
Saruta J Tsukinoki K Sasaguri K Ishii H Yasuda M Osamura YR Watanabe Y Sato S 《Cells, tissues, organs》2005,180(4):237-244
Human saliva chromogranin A (CgA) is clinically promising as a psychological stress marker. However, expression of CgA is poorly understood in humans, although salivary gland localization of CgA in other mammals, such as rodents and horses, has been demonstrated. In the present study, we investigated the expression and localization of CgA in the human submandibular gland (HSG) using various methods. CgA was consistently localized in serous and ductal cells in HSG, as detected by immunohistochemistry and in situhybridization. Reactivity was stronger in serous cells than in ductal cells. In addition, strong immunoreactivity for CgA was observed in the saliva matrix of ductal cavities. Western blotting gave one significant immunoreactive band of 68 kDa in the adrenal gland, HSG and saliva. Finally, CgA was detected in secretory granules of serous and ductal cells by immunoelectron microscopy. In conclusion, CgA in humans is produced by HSG and secreted into saliva. 相似文献
87.
Mitsuo Masuno Jun-Ichi Asano Kanji Yasuda Tomio Kondo Tadao Orii 《American journal of medical genetics. Part A》1993,45(1):65-67
We report on a 19-month-old girl with a derivative chromosome 9 and a recombinant chromosome 12 resulting from a maternal balanced complex rearrangement involving chromosomes 8, 9, and 12. The karyotype of the phenotypically normal mother was 46,XX,t(8;12) (9;12) (8qter→8p23::12q12→12q15::9q32→9qter;9pter→9q32::12q15→12qter;12pter→12q12::8p23→8pter). The child's karyotype was 46,XX,?9,?12, +der(9) (9pter→9q32::12q15→12qter),+rec(12) (12pter→12q15::9q32→9qter) mat. The child had severe growth retardation, minor anomalies including trigonocephaly, hypertelorism, broad nasal root, apparently low-set and posteriorly angulated ears, triangular face, pectus carinatum, clinodactyly of fifth fingers, and almost normal psychomotor development. To the best of our knowledge, there have been only 3 previous reports of recombination derived from parental complex chromosome rearrangements. In the recombination products, the chromosomes were apparently balanced and the offspring had no clinical abnormalities. The present case exhibited abnormalities and may have a submicroscopic aberration of 12q arising from crossing over during maternal meiotic pairing, although her chromosomes appeared to be balanced. © 1993 Wiley-Liss, Inc. 相似文献
88.
K. Miyamoto J. Nagakawa I. Hishinuma K. Hirota M. Yasuda T. Yamanaka K. Katayama I. Yamatsu 《Inflammation research》1992,37(3-4):297-304
E3330 {(2E)-3-[5-(2,3-dimethoxy-6-methyl-1,4-benzoquinoyl)]-2-nonly-2-propenoic acid}, a novel synthesized hepatoprotective compound, has suppressive effects on tumor necrosis factor- (TNF-) generation from monocytes/macrophagesin vitro. E3330 (1–100 M) reduced lipopolysaccharide (LPS, 10 mg/ml or 1g/ml)-induced TNF- generation from rat resident andPropionibacterium acnes (P. acnes)-elicited peritoneal macrophages, rat and human monocytes, rat Kupffer cells, and splenic mononuclear cells in a concentration-dependent manner. E3330 also (1–100 M) suppressed TNF- generation stimulated with egg-albumin immune complex in ratP. acnes-elicited peritoneal macrophages. Northern blot analysis showed that LPS-induced expression of TNF- messenger RNA (mRNA) in human blood monocytes was suppressed by E3330. These findings indicate that E3330 has a suppressive effect on TNF- generation from monocytes/macrophages, regardless of origin or species, and this effect is based in part on the suppression of TNF- mRNA expression. 相似文献
89.
90.
Effects of exhaustive exercise on biochemical characteristics of sarcoplasmic reticulum from rat soleus muscle 总被引:3,自引:0,他引:3
Yasuda T Inashima S Sasaki S Kikuchi K Niihata S Wada M Katsuta S 《Acta physiologica Scandinavica》1999,165(1):45-50
This study examined the effects of acute high-intensity and moderate-intensity exercise on Ca2+-stimulated adenosine triphosphatase (ATPase) activity and the Ca2+ and ATP dependence of Ca2+-ATPase of the sarcoplasmic reticulum (SR) in the soleus muscle. The rats were run on 10% grade at 50 m min(-1) or 25 m min(-1) until fatigued (avg. time to exhaustion 2.8 and 87.7 min, respectively). The catalytic activities of SR Ca2+-ATPase were significantly depressed immediately after both types of exercise. Kinetic analyses demonstrated that the Ca2+ affinity of Ca2+-ATPase was elevated by both types of exercise adopted in the present investigation whereas the increase in the ATP affinity was brought about by only high-intensity exercise. These results suggest that exhaustive exercise may induce in slow-twitch muscle fibre the environmental changes, which adversely affect SR Ca2+-ATPase activity and can overcome the positive influence arising from the increase in the Ca2+ and/or ATP affinities of SR Ca2+-ATPase. 相似文献