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1.
Masatoshi Kataoka Keizoh Kawamura Tamotsu Kondoh Yoichi Wakano Hiroshi Ishida 《FEMS microbiology letters》1993,107(1):111-114
Abstract A factor showing inhibitory activity against human gingival fibrolasts was extracted from the cytosol fraction of Actinobacillus actinomycetemcomitans Y4. The activity markedly inhibited the proliferation of human gingival fibrolasts, but had no effect on cell viability or gross morphology. No such activity was found in cytosol fractions from either Porphyromonas gingivalis 381 or Escherichia coli HB101. The extract from A. actinomycetemcomitans Y4 was then purified by anion-exchange chromatography, hydroxyapatite chromatography and gel-filtration chromatography to give a single band on SDS-PAGE with an apparent molecular mass of 65 kDa. The purification ratio was 183-fold with a recovery rate of 5% compared with the crude extract (starting material) when the activity was assessed by direct cell counts. 相似文献
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Endo S Inada K Inoue Y Otsu T Kasai T Kuwata Y Hoshi S Yoshida M 《Mediators of inflammation》1992,1(1):45-48
Plasma levels of endotoxin and various cytokines were assessed in 70 patients with gastrointestinal tract perforation. Sepsis developed in 29 of them, and eight of these (27.6%) had on admission endotoxin levels higher than 9.8 pg ml(-1). The clinical outcome correlated with the level of tumour necrosis factor alpha (TNFalpha), rather than with the endotoxin level. The high interleukin 6 (IL-6) level was shown in septic patients and no correlation was observed between the IL-6 level and the clinical outcome. Plasma TNFalpha levels tended to change independently from endotoxin levels, suggesting that TNFalpha may have been locally produced in inflammatory lesions. 相似文献
5.
R Y Osamura Y Suemizu S Yoshimura S Hori K Inada K Watanabe Y Nakai H Imura 《Peptides》1991,12(3):503-507
In order to elucidate the relationship between secretory pathway and processing for precursor molecule of peptide hormones, we performed immunoelectron microscopic studies to localize POMC-derived peptides in mouse cultured L cells (fibroblasts without secretory granules) and in mouse AtT20 cells (ACTH secreting pituitary tumor cells with secretory granules) which had been transformed with human POMC gene. From the electron microscopic localization patterns, L42 cells were considered to serve as a model of constitutive pathway without processing of POMC, and A53 cells were considered to serve as a model of transgranular (regulated) pathway with processing of POMC. Immunoblotting supported these interpretations. 相似文献
6.
K Inada S Endo K Takahashi M Suzuki T Narita T Yoshida H Suda T Komuro M Yoshida 《Microbiology and immunology》1991,35(4):303-314
We established a new method of plasma treatment for the removal of interfering factors in the plasma to allow detection of endotoxin by limulus test. The limulus test used was an endotoxin-specific chromogenic test, the Endospecy test. Perchloric acid (PCA) treatment and centrifugation (PCA method) is usually used to remove interfering factors from plasma, with the precipitate being discarded and the supernatant used to detect endotoxin. As the solubilized precipitates of endotoxin-spiked plasma and some patient plasma were found to contain the Endospecy activity, we have devised a new method assaying endotoxin in both the supernatant and precipitate. This study confirmed that the solubilized precipitate of endotoxin-spiked plasma had Endospecy activity and found that the precipitate had other endotoxin activities, such as lethality in galactosamine-sensitized mice and pyrogenicity in rabbits. We also confirmed that interfering factors were completely removed from plasma samples by this new method. The endotoxin level after the new PCA method was found to be about 8 times higher than that determined after PCA treatment and the new PCA method surpasses the conventional PCA method with regard to the positive rate of endotoxin contents in clinical samples. These results indicate that the new PCA method is superior to the PCA method as a plasma pretreatment method for limulus test. 相似文献
7.
A square matrix of spots (A) was presented in rapid alternation with an uncorrelated matrix (B). If the square arrays are superimposed spatially one sees random incoherent motion. However, incoherent motion was seen only if the outer edges were exactly aligned. If the outline of matrix A is shifted horizontally by 1 degree in relation to B, then the edges are seen to oscillate to and fro. Surprisingly, all the dots in the matrix were seen to 'adhere' to the edges and to move horizontally (Ramachandran, 1981). We then aligned the edges again to produce incoherent motion and superimposed a sine-wave grating on the pattern. If the grating was moved horizontally then all the spots 'adhered' to it and moved horizontally as well. This illusion ('motion capture') was optimal (a) at a 90 degrees spatial phase shift of the grating; (b) at low spatial frequencies (less than 0.5 cycles); and (c) when the grating was alternated in step with the dot patterns. Density modulated gratings were just as effective. We conclude that the unambiguous motion signal derived from the grating is applied spontaneously to the dots as well. 相似文献
8.
A. Ajima T. Yoshimoto K. Takahashi Y. Tamaura Y. Saito Y. Inada 《Biotechnology letters》1985,7(5):303-306
Summary A hydrophobic substrate, 10-hydroxydecanoic acid having two functional groups (–OH and –COOH) in the molecule, was polymerized by ester bond formation with the polyethylene glycol-modified lipase in a transparent benzene solution. The polymer of 10-hydroxydecanoic acid was linearly elongated under a quite mild condition. 相似文献
9.
A previous study demonstrated the preparation of an antiserum having enough specificity and sensitivity for a radioimmunoassay to determine fragment D-dimer derivatives. Using the antiserum the contents of fragment D-dimer derivatives in the sera of normal subjects and patients were determined. The content in normal subjects was 0.260 +/- 0.07 micrograms/ml (mean +/- SD) an that in patients with elevated levels of FDP ranged from 0.30 to 28 micrograms/ml. The values of fragment D-dimer derivatives and FDP in sera of some patients did not necessarily change in parallel, although there seems to be generally a positive correlation between them. 相似文献
10.
Soichi Kojima Wakako Soga Hiromi Hagiwara Motoyuki Shimonaka Yuji Saito Yuji Inada 《Bioscience reports》1986,6(12):1029-1033
We have succeeded in corroborating the enhancing effect of vitamin A, vitamin C, sitosterol and fucosterol on the fibrinolytic activity of endothelial cells. The assay system consisted of anin situ dissolution of a fibrin layer coated onto a culture dish, over which endothelial cells were grown in a culture medium containing 10 % serum. The dissolution was enhanced by the addition of these vitamins and phytosterols to the culture medium.To whom correspondence should be addressed. 相似文献