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131.
Exercise-induced hyperketonemia was investigated using streptozotocin (STZ)-diabetic rats subjected to running exercise on a treadmill. The degrees of hyperketonemia after 50, 55 and 60% VO2max of exercises were similar in mild diabetic rats (fasting plasma glucose; FPG less than 11 mM). The degree of hyperketonemia (especially an increase in acetoacetate; AcAc) after 60% VO2max of exercise was correlated with FPG (P less than 0.01) and basal plasma ketone bodies (P less than 0.01). Prolonged training with 60% VO2max of exercise for 30 min 3 times per week for 6 wks reduced the increase in plasma ketone bodies induced by the exercise in both mild (FPG less than 11 mM) and severe (FPG greater than 22 mM) diabetic rats. The exercise-induced increase in plasma glucagon in mild diabetic rats and free fatty acids (FFA) in severe diabetic rats are also reduced by the training. These results demonstrate that exercise-induced hyper-AcAc-emia correlated with the FPG level is reduced by prolonged training in diabetic rats, and might suggest that exercise-induced hyperketonemia is reduced by long-term exercise training also in diabetic patients. 相似文献
132.
Effect of Ammonia on Cellular pH of Anabaena cylindrica Determined with 31P NMR Spectroscopy 总被引:1,自引:0,他引:1
Ohmori Masayuki; Oh-hama Tamiko; Furihata Kazuo; Miyachi Shigetoh 《Plant & cell physiology》1986,27(3):563-566
The pH changes in the blue-green alga (cyanobacterium) Anabaenacylindrica caused by addition of ammonia were investigated using31P NMR spectroscopy. A pH shift of 0.9 or more was observedwhen 30 nM NH4OH was added to the cell suspension, but no significantcellular pH change was observed with 50 mM NH4CI, a concentrationhigh enough to stimulate dark CO2 fixation of this alga. Thechange in cellular pH does not seem to cause ammonia-inducedstimulation of dark CO2 fixation. (Received June 22, 1985; Accepted January 10, 1986) 相似文献
133.
134.
We have isolated E. coli mutants which can grow at 30 degrees C but not at 42 degrees C and are able to harbor the oriC plasmid (minichromosome) at a higher copy number than the parental wild-type strain at the permissive temperature. The mutants were found to contain higher amounts of chromosomal DNA per mg protein than the wild-type, whether or not they harbor the plasmid. Experimental results suggest that the higher amount of chromosomal DNA is due to a higher copy number of chromosomes and not to a larger amount of DNA per chromosome. These properties in each of the mutants are caused by a single mutation at the rpoB or rpoC gene that code for the beta or beta' subunit of RNA polymerase, respectively. The mutations are thought to affect the regulation of replication of oriC-bearing replicons, that is, the E. coli chromosome and oriC plasmids, but not the miniF plasmid. 相似文献
135.
Phase relationships in solutions of rodlike, molecules were investigated with solutions of poly(γ-benzyl L -glutamate) having degrees of polymerization of 1500 and 3600, in N,N′-dimethylformamide–methanol and in N,N′-dimethylformamide–water at 30°C. With these systems, corresponding boundary curves for isotropic and anisotropic solution were obtained as a function of composition. Phase diagrams for these ternary systems were analysed on the basis of a theoretical treatment by Flory for a binary system consisting of a rodlike polymer and a solvent and found to be in good agreement with that predicted theoretically. For example, the polymer concentration above which the isotropic phase cannot exist and that of anisotropic conjugate phase agree with the values calculated. Furthermore, viscosities were measured as a function of polymer concentration by the falling-sphere method to confirm the boundary composition between the isotropic solution and heterogeneous region. These results were also found to coincide with those on phase equilibrium. 相似文献
136.
137.
The structure of glutaraldehyde (GA) in aqueous solutions has been the subject of much debate. Since there were fundamental problems in the experiments in the preceding studies, in this article, the structure of GA was investigated with uv absorption and light scattering to avoid those problems. It was discovered that 70% glutaraldehyde solution contains a large quantity of polymeric species with cyclic hemiacetal structure. On dilution, the polymerized glutaraldehyde slowly converted to monomers. In dilute solution, glutaraldehyde is almost monomeric at pH 3-8, the major portion taking the cyclic hemiacetal structure. The structure of GA in 20% solution is similar to that in more dilute solution. alpha, beta-Unsaturated structure does not exist in aqueous solution regardless of the concentration of glutaraldehyde. 相似文献
138.
J Miki T Matsuda H Kariya H Ohmori T Tsuchiya M Futai H Kanazawa 《Archives of biochemistry and biophysics》1992,294(2):373-381
To analyze relationships between the ternary and primary structures of the beta subunit of Escherichia coli F1 ATPase, we prepared two monoclonal antibodies beta 12 and beta 31 against the beta peptide. These antibodies bind to the beta subunit but do not bind to the F1 ATPase, resulting in no inhibition of the ATPase activities. Several different portions of the beta subunit peptide were prepared by constructing expression plasmids carrying the corresponding DNA segment of the beta subunit gene amplified by the polymerase chain reaction. Western blotting analysis using these peptides revealed that the antibodies bound to a peptide of 104 amino acid residues from the amino terminal end, which is outside the previously estimated catalytic domain between residues 140 and 350. These results indicated that the amino terminal portion of the maximal 104 residues is not exposed to the surface of the F1 ATPase. The binding spectrum of the antibodies to the subunit from various species including Vibrio alginolyticus and thermophilic bacterium PS3 indicated possible epitope sequences within the 104 residues. The ternary structure of the beta subunit, in terms of cleavage sites by endopeptidases, was analyzed using the antibodies. A 43-kDa peptide without binding ability to beta 12 and beta 31 appeared upon cleavage by lysyl endopeptidase. The results suggested that lysyl residues from around 70 to 100 from the amino terminus are exposed to the surface of the beta subunit. 相似文献
139.
Standard sulphur amino acids and various cystathionine metabolites in the urine of a patient with cystathioninuria were analysed using liquid chromatography/mass spectrometry with an atmospheric pressure ionization interface system. Very intense quasi-molecular ions ([M + H]+) of synthetic cystathionine, N-monoacetylcystathionine, perhydro-1,4-thiazepine-3,5-dicarboxylic acid, S-(3-hydroxy-3-carboxy-n-propyl)cysteine, S-(2-carboxyethyl) cysteine, S-(2-hydroxy-2-carboxyethyl)homocysteine, S-(carboxymethyl)homocysteine, N-acetyl-S-(3-hydroxy-3-carboxy-n-propyl)cysteine and N-acetyl-S-(2-carboxyethyl)cysteine were observed by this method. Quasi-molecular ions ([M + H]+) of these sulphur amino acids were observed in the urine sample of the patient with cystathioninuria, and N-acetyl-HCPC and N-acetyl-beta-CEC as N-substituted sulphur amino acids were also identified in the urine of the same patient. 相似文献
140.
S Hanazawa C Hanaizumi S Amano K Hirose Y Ohmori M Kumegawa K Yamaura S Kitano 《Journal of cellular physiology》1988,136(3):543-546
We used the mouse monocyte/macrophage-like tumor cell line P388D1 to test whether or not interleukin-1 (IL-1) stimulates differentiation of monocyte/macrophage progenitors. Incubation of these cells with recombinant human interleukin-1 (rhIL-1) alpha and beta resulted in their increased adherence, stimulation of nonspecific esterase activity, and increased Fc rosette formation. rhIL-1s inhibited cell growth and stimulated Fc rosette formation in a dose-dependent fashion. The cell growth inhibition due to rhIL-1s depended on the concentration of serum in culture medium. Synergism between rhIL-1 and calcium ionophore A23187 was found for the cell growth inhibition and Fc rosette formation. The presence of ethylene glycol bis- (beta-aminoethyl ether) N,N,N,N,-tetraacetic acid(EGTA) in the medium abolished the stimulatory effect of rhIL-1 on Fc rosette formation of the cell line. These results demonstrate that rhIL-1s are a potent inducer of the differentiation of the macrophage-like tumor cell line P388D1. 相似文献