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11.
Induced optical activity in poly-L-lysine-methyl orange system 总被引:1,自引:0,他引:1
The absorption and cicular dichroism spectra of the complex of poly-L -lysine (PLL) in the random coil form with methyl orange (MO) have been measured in aqueous solution. A new absorption band is observed at the shorter wavelength compared with that of the free dye. Although MO does not show a formation of dimer or aggregation with an increase in concentration, circular dichroism bands are observed at the wavelength corresponding to the wavelength of the new absorption band. These induced circular dichroism bands may arise from the dimeric MO molecules bound to PLL in the random coil form. The main contribution to the interaction between MO molecules is shown to be the electro static interaction. The observed circular dichroism spectra and the configuration of dimeric MO molecules bound to PLL can be explained by the dipole couping mechanism. 相似文献
12.
The process of sub-culture propagation among Japanese macaques 总被引:1,自引:1,他引:0
Syunzo Kawamura 《Primates; journal of primatology》1959,2(1):43-60
13.
Nariko Kawamura 《Neurochemical research》1989,14(1):9-15
The interrelation of palmitate oxidation with amino acid formation in rat brain mitochondria has been investigated in purified mitochondria of nonsynaptic origin by measuring the formation of aspartate, -ketoglutarate, and glutamate during palmitate oxidation, and also by assaying14C-products of [1-14C]palmitate oxidation. Oxidation of palmitate (or [1-14C]palmitate) resulted in the formation of aspartate (or14C-aspartate), and the oxidation was inhibited by aminooxyacetate (an inhibitor of transaminase), Palmitate oxidation also resulted in -ketoglutarate formation, which was sensitive to the effect of aminooxyacetate. Addition of NH4Cl was found to increase14C-products and formation of -ketoglutarate, whereas glutamate formation was not increased unless the rate of palmitate oxidation was reduced by 50% by aminooxyacetate or -ketoglutarate was added exogenously. Exogenous -ketoglutarate was found to decrease14C-products, but not aspartate formation. These results indicated that palmitate oxidation was closely related to aspartate formation via aspartate aminotransferase. During palmitate oxidation without aminooxyacetate or added -ketoglutarate, however, -ketoglutarate was not available for glutamate formation via glutamate dehydrogenase. We discuss the possibility that this was because (a) oxidative decarboxylation of -ketoglutarate to form succinyl-CoA was favored over glutamate formation for the competition for -ketoglutarate in the same pool, and (b) the pool of -ketoglutarate produced in the aspartate aminotransferase reaction did not serve as substrate for glutamate formation. 相似文献
14.
The release of hemoglobin from human erythrocytes hemolyzed beforehand by hydrostatic pressure, osmotic pressure, and freeze-thaw methods was examined as a function of temperature (0-45 degrees C) and pH (5.5-8.8) at atmospheric pressure. Only in the case of high pressure (2,000 bar) did the release of hemoglobin increase significantly with decreasing temperature and pH. Maleimide spin label studies showed that the temperature and pH dependences of hemoglobin release were qualitatively explicable in terms of those of the conformational changes of membrane proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of membrane proteins showed the diminution of band intensities corresponding to spectrin, ankyrin, and actin in the erythrocytes hemolyzed by high pressure. Cross-linking of cytoskeletal proteins by diamide stabilized the membrane structure against high pressure and suppressed hemoglobin release. These results indicate that the disruption of cytoskeletal apparatus by high pressure makes the membrane more leaky. 相似文献
15.
16.
Gene expression of metalloproteinase and its inhibitor in mesangial cells exposed to high glucose. 总被引:3,自引:0,他引:3
M Kitamura A Kitamura T Mitarai N Maruyama R Nagasawa T Kawamura H Yoshida T Takahashi O Sakai 《Biochemical and biophysical research communications》1992,185(3):1048-1054
To clarify the roles of metalloproteinases and their inhibitor (TIMP) in diabetic glomerulopathy, we studied the effect of a high glucose concentration on the gene expression of metalloproteinase transin and TIMP as well as collagen type IV and laminin in cultured rat mesangial cells (MCs). In the high glucose group, collagen type IV, laminin, and TIMP mRNA levels were all elevated in a concentration-dependent manner, whereas transin expression was suppressed. Osmotic control of high glucose with mannitol selectively stimulated TIMP expression. We hypothesize that high glucose decreases matrix-degrading activity as well as increases matrix productivity in MCs. 相似文献
17.
A procedure for the mass propagation of multiple shoots of Stevia rebaudiana is described. Isolated shoot primordia were used as the inoculum to obtain clusters of shoot primordia. Such clusters were grown in a 500 liter bioreactor to obtain shoots. A total of 64.6 Kg of shoots were propagated from 460 g of the inoculated shoot primordia. These shoots were easily acclimatized in soil. 相似文献
18.
Rhodopsinlike opsins constitute a distinct phylogenetic group (Yokoyama 1994, Mol. Biol. Evol. 11:32–39). This RH2 group includes the green-sensitive opsins in chicken and goldfish and the blue-sensitive opsin in a nocturnal lizard gecko. In the present study, we isolated and sequenced the genomic DNA clones for the RH2 opsin gene, rh2
Ac
, of the diurnal lizard Anolis carolinensis. This single-copy gene spans 18.3 kb from start to stop codons, making it the longest opsin gene known in vertebrates. Phylogenetic analysis strongly suggests that rh2
Ac
is more closely related to the chicken green opsin gene than to the gecko blue opsin gene. This gene tree differs from the organismal tree, where the two lizard species should be most closely related, implying that rh2
Ac
and the gecko blue-sensitive opsin genes have been derived from duplicate ancestral genes.Correspondence to: S. Yukiyama 相似文献
19.
Rika Morishita Shinsuke Saga Noriko Kawamura †Yoshio Hashizume ‡Toshiaki Inagaki Kanefusa Kato Tomiko Asano 《Journal of neurochemistry》1997,68(2):820-827
Abstract: The localization of two forms of the γ subunit of G proteins, γ3 and γ12, was examined in the mammalian brain. Concentrations of these two γ subunits increased markedly, as did those of glial fibrillary acidic protein, during postnatal development in the rat cerebral cortex. In aged human brains, by contrast, the concentration of γ3 tended to decrease with age, whereas that of γ12 in the temporal cortex increased slightly. An immunohistochemical study of human brains revealed that γ3 was abundant in the neuropil, whereas γ12 was localized in glial cells. In the hippocampal formation of aged human brains, levels of γ12-positive cells, as well as levels of glial fibrillary acidic protein- and vimentin-positive astrocytes, increased, in particular in the CA1 subfield and the prosubiculum, in which there was a decrease in the number of pyramidal cells. The appearance of γ12-positive cells associated with the loss of pyramidal cells was also observed in the hippocampus of rats that had been treated with kainic acid. These results indicate that γ12 is strongly expressed in reactive astrocytes. In a study of cultured neural cells, we found that γ12 was predominant in glioma cells, such as C6 and GA-1 cells, in contrast with the specific localization of γ3 in PC12 pheochromocytoma cells, which are neuron-like cells. Taken together, the results indicate that γ3 and γ12 are selectively expressed in neuronal and glial cells, respectively, and that concentrations of γ3 and γ12 in the brain are related to the numbers and/or extent of maturation of these cells. 相似文献
20.