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51.
Hana Dolezalova Matej Stepita-Klauco Jan Kucera Hideyuki Uchimura Makoto Hirano 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1978,146(1):67-76
Concentrations of cadaverine, monoacetylcadaverine and monopropionylcadaverine in the blood of schizophrenic and nonschizophrenic subjects were measured. Two groups, one from the U.S.A. the other from Japan, were tested. Monoacetylcadaverine and monopropionylcadaverine were found elevated in the blood of some schizophrenic patients in comparison with those in controls in each group. Their increase could be caused by a reduced monoamine oxidase activity or by an increased acylation in schizophrenic patients. 相似文献
52.
N-Formyl, N-chloroacetyl, N-glycyl, N-isobutyryl, and N-pentanoyl derivatives of chitosan have been prepared. N-Acetylchitosan was the derivative most susceptible to chitinase from Streptomyces griseus and lysozyme from chicken egg-white, but the susceptibility was not restrictive. The relative rates of hydrolysis by chitinase with respect to R in the RCONH group were CH3 > CH3CH2 > H > CH3CH2CH2 > (CH3)2CH > NH2CH2 > ClCH2. Neither enzyme hydrolysed chitosan or its N-methylene, N-benzylidene, N-benzoyl, N-nicotinyl, and N-fatty acyl (C5C18) derivatives, and lysozyme did not hydrolyse N-butyrylchitosan. N-Acetylhexanoyl-chitosans, which had d.s. ratios of ~0.7: ~0.3 and ~0.3; ~0.7, were hydrolysed at ~0.75 and ~0.04 of the rate of N-acetylchitosan (powder) by chitinase. O-Acylation of N-acylchitosans caused a decrease in the rates of hydrolysis by chitinase. N-Acetylchitosan gels were hydrolysed at 8–13 times the rate for crab-shell chitin. These results indicate that not only N- and O-substituents but also the physical form of the substrates influence the rates of hydrolysis by these enzymes. 相似文献
53.
54.
Aminoacylase was immobilized on the mycelium pellets of Aspergillus ochraceus by using albumin and glutaraldehyde. No difference in the optimum pH was observed between native aminoacylase and aminoacylase pellets. The aminoacylase pellets were stable in pH 4-8 but they were unstable in alkaline conditions. The aminoacylase pellets were more stable against heavy metal ions and inhibitors than native aminoacylase. However, the degree of the activation of aminoacylase with cobalt ion decreased with the immobilization. It was suggested that most of aminoacylase was covalently coupled to the mycelium with glutaraldehyde. 相似文献
55.
Methyl 4,6-O-benzylidene-2-deoxy-α-D-ribo-hexopyranoside (1) is converted into methyl 3,4-di-O-benzoyl-6-bromo-2,6-dideoxy-α-D-ribo-hexopyranoside (3) via the 3-O-benzoyl derivative (2) of 1 by subsequent treatment with N-bromosuccinimide. Compound 3 is the key intermediate in high-yielding, preparative syntheses of the title dideoxy sugars, which are constituents of many antibiotics. Dehydrohalogenation of 3 affords the 5,6-unsaturated glycoside 7. which undergoes stereospecific reduction by hydrogen with net inversion at C-5 to give methyl 3,4-di-O-benzoyl-2,6-dideoxy-β-L-lyxo-hexopyranoside (8), whereas reductive dehalogenation of 3 provides the corresponding D-ribo derivative 4. The unprotected glycosides 9 (L-lyxo) and 5 (D-ribo) are readily obtained by catalytic transesterification, and mild, acid hydrolysis gives the crystalline title sugars 10 (L-lyxo) and 6 (D-ribo) in 45 and 57% overall yield from 1 without the necessity of chromatographic purification at any of the steps. 相似文献
56.
T Hirano T Sudo T Teranishi K Fujimoto M Iizuka S Kobayashi K Onoue 《Microbiology and immunology》1983,27(1):87-94
Poly(A)-positive mRNA extracted from tonsillar mononuclear cells stimulated with phytohemagglutinin-M and 12-o-tetradecanoyl phorbol 13-acetate was successfully translated into biologically active interleukin 2 (IL-2) in Xenopus laevis oocytes, and secreted into the incubation medium. In control experiments, the extract of oocytes injected with either poly(A)-negative RNA or buffer did not show any IL-2 activity. By sucrose density gradient centrifugation analysis, IL-2 mRNA was found as a single peak corresponding to a sedimentation coefficient of 10-11S. 相似文献
57.
H Miyajima T Hirano S Hirose H Karasuyama K Okumura Z Ovary 《Journal of immunology (Baltimore, Md. : 1950)》1991,146(2):457-462
IgE production was obtained from B cells of BALB/c or nude mice when these cells were cultured with IL-4 plus LPS. IL-2 added to these cultures at the start (day 0), 1 or 2 days later completely suppressed the production of IgE. The production of IgG1 was also inhibited, but only if IL-2 was added on day 0. The production of other isotypes (IgM, IgG2a, IgG2b) was only slightly decreased by addition of IL-2. No suppression of IgE or IgG1 production was observed if monoclonal anti-IL-2 was added, whereas anti-IFN-gamma had no effect on the suppression of the production of these isotypes. The expression of CD23 on the third day of culture on B cells stimulated with LPS and IL-4 was markedly decreased when IL-2 was added to the cultures on day 0. Addition of monoclonal anti-IL-2 suppressed all effects produced by IL-2, whereas addition of anti-IFN-gamma had no effect. These results show that the suppression by IL-2, at least for the first signaling processes, are different from the suppression produced by IFN-gamma. 相似文献
58.
Kiyofumi Asai Takayoshi Hirano Shuji Kaneko Akihiko Moriyama Keiko Nakanishi Ichiro Isobe Yaman Z. Eksioglu Taiji Kato 《Journal of neurochemistry》1992,59(1):307-317
Neurofibroma tissue was investigated for the presence of glial growth modulators that would suppress the proliferation of glial cells. A novel endogenous polypeptide inhibitor of proliferation and DNA synthesis in glial cells, gliostatin, was purified from the extracts of neurofibroma by a procedure comprising dye and anion-exchange column chromatography, and HPLC. A monoclonal antibody raised against partially purified gliostatin showed no cross-reactivity with known cytokines, but adsorbed the growth inhibitory activity of gliostatin and immunochemically visualized the putative gliostatin bands on western blot analyses. Although the product showed an apparent M(r) of 100,000 accompanied by an inhibitory activity on gel filtration column chromatography, it migrated at a lower apparent M(r) of 50,000 under the reducing conditions on western blotting, indicating that a homodimeric structure of native gliostatin consisted of 50-kDa subcomponents. Gliostatin was a potent growth inhibitor acting at nanomolar concentrations against all glial tumor cells and glia maturation factor-stimulated astroblasts, but not neuronal cells. 相似文献
59.
Subacute sclerosing panencephalitis virus dominantly interferes with replication of wild-type measles virus in a mixed infection: implication for viral persistence. 下载免费PDF全文
A Hirano 《Journal of virology》1992,66(4):1891-1898
Interaction between the Edmonston or Nagahata strain of acute measles virus (MV) and the defective Biken strain of MV isolated from a patient with subacute sclerosing panencephalitis (SSPE) was examined by a cell fusion protocol. Biken-CV-1 cells nonproductively infected with Biken strain SSPE virus were fused with neomycin-resistant CV-1 cells. All the fused cells selected with the neomycin analog G418 expressed Biken viral proteins, as determined by an immunofluorescence assay. This procedure enabled the transfer of Biken viral genomes into cells previously infected with MV. In the fused cells coinfected by Biken strain SSPE virus and Edmonston or Nagahata strain MV, early MV gene expression was suppressed, as determined by immunoprecipitation with strain-specific antibodies. Maturation of Edmonston strain MV was also suppressed. When the coinfected fused cells were selected with G418, Biken viral proteins remained at a constant level for up to 7 weeks. Wild-type MV proteins gradually decreased to a barely detectable level after 4 weeks and became undetectable after 7 weeks. Immunofluorescence studies showed a steady decline in cells expressing wild-type MV proteins in the coinfected cultures. These results suggest that Biken strain SSPE virus dominantly interferes with the replication of wild-type MV. The possible mechanisms of dominant interference and the implication for evolution of a persistent MV infection are discussed. 相似文献
60.