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1.
N Kato I Nakashima M Ohta F Nagase T Yokochi S Naito 《Microbiology and immunology》1980,24(11):1043-1051
The time course of development and decline of the ability of BCG-infected mice to produce interferon in the serum in response to the intravenous infection of purified protein derivative of tuberculin (PPD) was very similar to that of their systemic hypersensitivity to PPD. A cytotoxic factor (cytotoxin) was produced in parallel with interferon in the serum of BCG-infected mice after stimulation with PPD. The duration of the period in which cytotoxin-production responsiveness to PPD was definitely detectable was much shorter than that for interferon-production responsiveness although the periods for the maximum production of interferon and cytotoxin coincided. The kinetics of release of interferon in the serum of BCG-infected mice after stimulation with PPD did not parallel that of release of cytotoxin. The four kinds of activities, interferons and cytotoxins induced by PPD and lipopolysaccharide (LPS) in the serum of BCG-infected mice, were compared for their stability to heating at 56 C and to treatment at pH 2. The kinetics of inactivation of these four activities differed significantly, when the serum was either heated at 56 C or treated at pH 2. Interferon produced in response to LPS could be neutralized by anti-L cell(NDV) interferon rabbit serum as easily as L cell (NDV) interferon, 16 times as much antiserum was required to neutralize the same amount of interferon in response to PPD, but cytotoxins induced by PPD and LPS were not neutralized at all by the antiserum. From these findings it is thought likely that interferons and cytotoxins induced by PPD and LPS in the serum of BCG-infected mice are different substances, although the antigenic relationship between cytotoxins induced by PPD and LPS remains unknown. 相似文献
2.
Keisuke Hanaki Tomonori Matsuo Michihiko Nagase 《Biotechnology and bioengineering》1981,23(7):1591-1610
The inhibitory effect of long-chain fatty acids on the anaerobic digestion process was examined in batch experiments using synthetic substrates. The addition of long-chain fatty acids caused the appearance of the appearance of the lag period in the methane production from acetate and in the degradation of both long-chain fatty acids and n-butyrate. Methane production from hydrogen proceeded without lag period although its rate was lowered. Fermentation of glucose was not inhibited. Neutral fat in the whole milk was easily hydrolyzed to long-chain fatty acids, which brought about the inhibition. The addition of calcium chloride reduced the inhibitory effect of long-chain fatty but it did not do so after the culture had been exposed to long-chain fatty acids for more than several hours. The addition of calcium carbonate could not reduce the inhibition because of its insolubility. 相似文献
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4.
F Nagase K Ueda K Kawashima S M Jamshedur Rahman K Isobe T Yoshida Y Hasegawa K Ando T Iwamoto E Nagura 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(7):2359-2365
When a murine leukemia L1210-specific Lyt-2+ T cell clone, K7L, was injected i.p. into CD2F1 mice together with L1210, the normal growth of L1210 in the peritoneal cavity of the mice at the early stage (days 0 to 5) was strongly inhibited, but L1210 grew progressively at the middle-stage (days 5 to 10), and then was rejected at the late stage (days 10 to 20). The mice thus survived for long times (more than 60 days), whereas the normal control injected with L1210 alone died within 14 days. The L1210 that grew at the middle stage in mice initially inoculated with L1210 together with K7L was a K7L-insensitive (K7L-) variant. All of eight tumor clones established from L1210-K7L- by limiting dilution was insensitive to the antitumor activity of K7L, and this property of tumor clones was stable after repeated in vitro passage. The initial depression of the L1210 growth by K7L followed by growth and rejection of the variant L1210-K7L- by the host T cell activity was then found to prepare a strong, long-lasting (more than 3 mo) immunity to protect mice against the high-dose (10(7) cells per mouse) challenge of original L1210. Corresponding to this result, definite tumor (L1210)-specific cytotoxic T lymphocyte (CTL) activity against both variant and original L1210 targets was developed by antigen (L1210) restimulation in the culture of spleen cells from these mice, but was not increased to a detectable level before L1210-K7L- variant started to grow. It was suggested that the 1210-K7L- variant and the original L1210 should have the common tumor-specific antigen that was independent of the K7L-reactive antigen, and that original L1210, whose growth was retarded by K7L, primed the host with the common antigen to be enormously boosted by the subsequently growing L1210-K7L- variant. 相似文献
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6.
The effects of medicinal plants on the mutagenicity of benzo[a]pyrene were studied with Salmonella typhimurium tester strains. The chosen medicinal plants are very frequently used as Chinese herbal medicines. Each medicinal plant was extracted with hot water, which is similar to the method used in Chinese medicinal treatment. Cinnamomi cortex, Rhei rhizoma, Scutellariae radix and Rehmanniae radix were found to decrease the mutagenic activity of benzo[a]pyrene. Atractylodis rhizoma also reduced the mutagenicity of benzo[a]pyrene, but this was not certain, because it showed a killing effect on the cell survival test. Bupleuri radix and Aurantii nobilis pericarpium had an enhancing effect, but then neither of these extracts is itself mutagenic. Each medicinal plant extract showed a different effect on the mutagenicity of benzo[a]pyrene. These effects were classified into 5 types: (I) decreasing effect, (II) killing effect, (III) enhancing effect, (IV) enhancing and decreasing effect and (V) inactive. 相似文献
7.
Teruo Okasora Mitsumasa Nagase Hiroshi Kawachi Katsuyuki Matsui Michiaki Orikasa Tetsuo Morioka Ichiroh Yamazaki Takashi Oite Fujio Shimizu 《Virchows Archiv. B, Cell pathology including molecular pathology》1991,60(1):41-46
Change in the localization of the antigen recognized by the proteinuria-inducing monoclonal antibody (MA) 5-1-6 in experimental nephrosis was studied by indirect and biotin-avidin immunofluorescence, and immunoperoxidase at light and electron microscopical levels. The proteinuric state was induced by the administration of the aminonucleoside of puromycin (PAN) or adriamycin. The antigen decreased in quantity and/or its distribution changed with an increase in the amount of protein excreted in both experimental models. Recovery from the alterations observed during the development and proteinuria appeared to occur when PAN-induced proteinuria subsided. This antigenic molecule may thus be essential for maintaining the normal permselectivity of glomerular capillary walls. 相似文献
8.
Influence of human recombinant interleukin-1 (hrIL-1) on collagen metabolism was investigated with rabbit uterine cervical fibroblasts. Enzyme-linked immunosorbent assays for collagenase and tissue inhibitor of metalloproteinases (TIMP) indicated that hrIL-1 participates in both stimulation of procollagenase production and suppression of TIMP synthesis by uterine cervical cells. IL-1 did not modulate collagen synthesis. In addition, the sensitivity to IL-1 of uterine cervix from ovariectomized rabbits was augmented by estradiol-17 beta treatment. Thus it is proposed that IL-1 accelerates collagenolysis in the cervical tissue and its effect on uterine cervix is hormonally regulated. 相似文献
9.
Interaction of palytoxin and cardiac glycosides on erythrocyte membrane and (Na+ + K+) ATPase 总被引:1,自引:0,他引:1
Palytoxin (PTX), at extremely low concentrations (0.01-1 nM), caused K+ release from rabbit erythrocytes. Among the various chemical compounds tested, cardiac glycosides potently inhibited the PTX-induced K+ release. The order of inhibitory potency (IC50) was cymarin (0.42 microM) greater than convallatoxin (0.9 microM) greater than ouabain (2.3 microM) greater than digitoxin (88 microM) greater than digoxin (90 microM). Their corresponding aglycones, even at 10 microM, did not inhibit the K+ release, but competitively antagonized the inhibitory effect of the glycosides. All these cardiotonic steroids inhibited the activity of (Na+ + K+)-ATPase prepared from hog cerebral cortex in narrow concentration ranges (IC50 = 0.15-2.4 microM), suggesting that the inhibition of K+ release is not related to their inhibitory potency on the (Na+ + K+)-ATPase activity, and the sugar moiety of cardiac glycosides is involved in the inhibition. On the other hand PTX, at higher concentrations (greater than 0.1 microM), inhibited the (Na+ + K+)-ATPase activity. However, this inhibitory effect of PTX was not antagonized by ouabain. It is suggested that, compared with ouabain, PTX has additional binding site(s) on the (Na+ + K+)-ATPase. 相似文献
10.
A proteinase inhibitor which has strong anti-collagenase activity was found in chicken egg white. The inhibitor (pI = 4.9) was purified by poly(ethylene glycol) (5.5-10%) precipitation and chromatography on Ultrogel AcA 34, DEAE-cellulose, and Sephacryl S-300. The final product was homogeneous on 5% polyacrylamide gel electrophoresis. Stoichiometric inhibition was observed with the inhibitor and rabbit synovial collagenase and thermolysin (1:1 molar ratio with thermolysin). The inhibitor ran on sodium dodecyl sulfate-gel electrophoresis with reduction as a single protein band of Mr = 165,000. The molecular weight of the native inhibitor was estimated to be 780,000 by sedimentation equilibrium centrifugation. Centrifugation analysis in 6 M guanidine hydrochloride and of the reduced sample gave M omega = 380,000 and M omega = 195,000, respectively, where M omega is the weight-average molecular weight determined by equilibrium ultra-centrifugation. The results indicated that the inhibitor molecule is a tetramer of identical subunits linked in pairs by disulfide bonds. Since the molecular weight and the quaternary structure of the inhibitor were similar to those of alpha 2-macroglobulin (alpha 2M) in plasma, chicken alpha 2M was isolated and compared with the inhibitor. The inhibitor was not sensitive to methylamine, whereas chicken alpha 2M was. No immunocross-reactivity was observed between the inhibitor and chicken alpha 2M. The NH2-terminal sequence of the egg white inhibitor is Lys-Glu-Pro-Glu-Pro-Gln-Tyr-Val-Leu-Met-Val-Pro-Ala. The sequence of chicken alpha 2M is Ser-Thr-Val-Thr-Glu-Pro-Gln-Tyr-Met-Val-Leu-Leu-Pro-Phe. Considerable homology was found between the two sequences and to the NH2-terminal sequence of human alpha 2M. Monospecific antibody raised against the egg white inhibitor was employed to examine the tissue distribution of the inhibitor. The inhibitor was found only in oviduct and egg white, but not in other tissues or serum of chickens. 相似文献