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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
3.
4.
Ono Mayumi Kuwano Michihiko Mizushima Shoji 《Molecular genetics and genomics : MGG》1979,170(1):11-23
Molecular Genetics and Genomics - Ribosomal protein S1 from a newly isolated Escherichia coli mutant has a molecular weight of about 54,000 which is smaller than the wild type S1 (M.W. 65,000). The... 相似文献
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A Kuroiwa K Matsubara T Nagase N Nomura J K Seong A Ishikawa R V Anunciado K Tanaka T Yamagata J S Masangkay V B Dang T Namikawa Y Matsuda 《The Journal of heredity》2001,92(3):282-287
The direct R-banding fluorescence in situ hybridization (FISH) method was used to map 18S-28S ribosomal RNA genes and 10 human cDNA clones on the chromosomes of the musk shrew (Suncus murinus). The chromosomal locations of 18S-28S ribosomal RNA genes were examined in the five laboratory lines and wild animals captured in the Philippines and Vietnam, and the genes were found on chromosomes 5, 6, 9, and 13 with geographic variation. The comparative mapping of 10 cDNA clones of human chromosome 1 demonstrated that human chromosome 1 consisted of at least three segments homologous to Suncus chromosomes (chromosomes 7, 10, and 14). This approach with the direct R-banding FISH method is useful for constructing comparative maps between human and insectivore species and for explicating the process of chromosomal rearrangements during the evolution of mammals. 相似文献
7.
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
8.
Degradation of type IX collagen by matrix metalloproteinase 3 (stromelysin) from human rheumatoid synovial cells 总被引:5,自引:0,他引:5
The degradation of type IX collagen, a minor collagen in cartilage, was examined by treatment with three different types of matrix metalloproteinases (MMPs) purified from the culture medium of rheumatoid synovial cells. Neither MMP-1 (collagenase) nor MMP-2 (so-called 'gelatinase') could digest type IX collagen, but MMP-3 (stromelysin) readily degraded it into smaller fragments. This suggests that MMP-3 may be responsible for the pathological degradation and/or normal turnover of type IX collagen. 相似文献
9.
Requirement of protein co-factor for the DNA-binding function of the human ski proto-oncogene product. 总被引:7,自引:3,他引:4
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We identified the human c-ski gene product (c-Ski) as a protein with the apparent molecular weight of 100,000, p100c-ski, by using a c-Ski-specific polyclonal antibody. p100c-ski was a nuclear protein and p100c-ski in nuclear extracts of Molt4 cells bound to calf thymus DNA cellulose, but the bacterially synthesized c-Ski did not, suggesting that Ski was associated with another protein(s) and that the Ski complex had DNA-binding activity. This hypothesis was supported by the finding that the bacterially synthesized Ski bounds to DNA cellulose after being mixed with a nuclear extract of Molt4 cells. By use of a series of deletion mutants of Ski synthesized in an in vitro translation system, two portions in Ski were found to be necessary for the DNA binding of the Ski complex: the N-proximal portion containing a cystein/histidine-rich domain and the C-terminal portion including a region rich in basic amino acids. 相似文献