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161.
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
162.
Yoshihisa Iwamoto Yusaku Suzuki Akinobu Kurita Yoko Watanabe Tadayori Shimizu Hirohisa Ohgami Yasutake Yanagihara 《Microbiology and immunology》1995,39(11):831-837
A new species, Vibrio trachuri sp. nov., was isolated from the cultured Japanese horse mackerel (Trachurus japonicus). These Vibrio were Gram negative, motile rods and formed yellow colonies on BTB teepol and TCBS plate, turned TSI medium to yellow and was sensitive to 150 μM O/129 (2,4-diamino-6,7-diisopropyl pteridine phosphate) like Listonella anguillarum which has been described as Vibrio anguillarum. However, the results of VP test and decarboxylation of lysine or dihydrolation of arginine suggested that these Vibrio are rather closely related to V. parahaemolyticus. DNA similarity determined by the microplate hybridization technique revealed that these Vibrio are genetically quite distant from Listonella anguillarum or V. parahaemolyticus and rather close to V. harveyi, although there was no Vibrio species which had more than 70% similarity value. From these results we propose to nominate Vibrio trachuri sp. nov. for this new Vibrio species. 相似文献
163.
Alternative splicing and genomic structure of the AML1 gene involved in acute myeloid leukemia. 总被引:17,自引:0,他引:17
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H Miyoshi M Ohira K Shimizu K Mitani H Hirai T Imai K Yokoyama E Soeda M Ohki 《Nucleic acids research》1995,23(14):2762-2769
164.
Phylogeny of symbiotic methanogens in the gut of the termite Reticulitermes speratus 总被引:3,自引:0,他引:3
Abstract The phylogeny of a symbiotic methanogen inhabiting the gut of a lower termite, Reticulitermes speratus , was analysed without cultivation. The small subunit ribosomal RNA gene (ssrDNA) and a 640-bp portion of the gene encoding subunit A of methyl coenzyme M reductase ( mcrA ) were amplified from a mixed-population DNA of the termite gut by polymerase chain reaction and cloned. The nucleotide sequence of the ssrDNA and the predicted amino acid sequence of the mcrA product were compared with those of the known methanogens. Both comparisons indicated that the termite symbiotic methanogen belonged to the order Methanobacteriales but was distinct from the known members of this order. 相似文献
165.
Tadamichi Shimizu Yuichi Takakuwa Hiroko Koizumi Teruo Ishibashi Akira Ohkawara 《Histochemistry and cell biology》1995,103(5):363-368
The presence and localization of immuno-analogues of human erythrocyte protein 4.1 and spectrin were examined in the epidermis of psoriasis vulgaris. Immunoblot analysis with antibodies against human erythrocyte protein 4.1 revealed that psoriatic epidermis contains a 4.1-like protein of 80 kDa, and also minor immunoreactive polypeptides, including a 45-kDa polypeptide. The 45-kDa band was not detected in non-lesional epidermis. Lesional epidermis of psoriasis contains spectrin-like proteins of 240 kDa. Analysis with immunofluorescence microscopy revealed that 4.1-like proteins were detected mainly in the cytoplasm of the suprabasal cells in lesional epidermis and in the peripheral cytoplasm of the basal cells in non-lesional epidermis. On the other hand, spectrin-like proteins were localized to the peripheral cytoplasm of basal keratinocytes in both lesional and non-lesional psoriatic epidermis. The present results indicate that proteins related to protein 4.1 and spectrin are consistently detected within epidermal cells of psoriasis, a chronic skin disease characterized by epidermal hyperplasia; the expression and distribution of protein 4.1 in lesional epidermis of psoriasis differs from that in non-lesional epidermis. These membrane skeletal proteins may be of significance in the hyperproliferative epidermis of psoriasis. 相似文献
166.
Hemoprotein catalysis of leukotriene formation 总被引:3,自引:0,他引:3
Incubation of various hemoproteins with 5-hydroperoxy-6,8,11,14-eicosatetraenoic acid or 15-hydroperoxy-5,8,11,13-eicosatetraenoic acid resulted in formation of epimeric 5(S),12-dihydroxy-6,8,10,14 -eicosatetraenoic acids and epimeric 8,15(S)-dihydroxy-5,9,11,13 -eicosatetraenoic acids, respectively. These dihydroxy acids were earlier recognized as nonenzymatic hydrolysis products of 5(S),6-oxido-7,9,11,14-eicosatetraenoic acid (leukotriene A4) and 14,15(S)-oxido-5,8,10,12-eicosatetraenoic acid (14,15-leukotriene A4). These allylic epoxides could be isolated as such from the hemoprotein incubations, and most probably they are intermediates in formation of the dihydroxy acids. 相似文献
167.
K. Kimata K. S. Brown S. Shimizu H. Murafa K. Yamada 《Histochemistry and cell biology》1984,80(6):539-545
Summary Mice homozygous for the autosomal recessive gene, cartilage matrix deficiency (cmd/cmd) are characterized by disproportionate
dwarfism and cleft palate and are suffered from genetic failure in biosynthesis of cartilagetype proteoglycans. To investigate
histochemical aspects of the defects in cartilaginous and other tissues of the mutant mice, complex carbohydrates in the tissues
have been studied by methods of light microscopy. As a result of the present investigations, the intercellular matrix of cartilaginous
tissues from the mutant was shown to exhibit weaker positive reactions for sulfated and acidic complex carbohydrates, as compared
with the corresponding tissues from the control. In certain muscular and nervous tissues from the mutant, the reactions for
sulfated complex carbohydrates tended to be weaker in intensity than those in the control. Furthermore, the dermal tissues
of the mutant showed apparent mastocytosis. All these results indicate that there exist accessory effects in non-cartilaginous
tissues in addition to the defects of cartilaginous tissues in the mutant mice. 相似文献
168.
Tadao Okazaki Masathosi Shimizu Carl E. Arbesman Elliott Middleton 《Prostaglandins & other lipid mediators》1978,15(3):423-427
Sera used in cell cultures contain significant amount of prostaglandins (PGs). In order to vaoid any effects of contaminating PGs, the present study employed a serum-free culture medium and confirmed the inhibitory effect of prostaglandin E (PGE) on the human lymphocyte activation which had been observed previously employing a serum-containing medium. PGE1 displayed a significantly stronger inhibitory effect on the cells than previously shown. Furthermore, reported enhancement of PGE synthesis by mitogen-activated lymphocytes could not be reproduced. 相似文献
169.
Yoshisada Fujiwara Toshiaki Higashikawa Mariko Tatsumi 《Journal of cellular physiology》1977,92(3):365-374
We investigated the cloning efficiency, DNA repair, and the rate of DNA replication in the skin fibroblasts from patients with Werner's syndrome (WS) of an autosomal recessive premature aging disease. Five WS strains exhibited normal levels of sensitivity toward X-ray and UV killings and repair of X-ray induced single strand breaks of DNA (rejoining) and UV damage to DNA (unscheduled DNA synthesis). The sedimentation of newly synthesizing DNA in alkaline sucrose gradients demonstrated a characteristic feature that only the elongation rate of DNA chains, estimated by the molecular weight increase, was significantly slower during early passages in WS cells than in normal Hayflick Phase II fibroblasts. In addition, plating efficiencies as well as the replicative potentials of five WS strains were more limited than those of normal cells under the identical culture conditions. It seems therefore that at least in the WS cells tested, the slow rate of DNA replication may be more related to the shortened lifespan and enhanced cell death, as manifestation of premature senescence at the cellular level, than be the DNA repair ability. 相似文献
170.
Ultraviolet action spectrum for anthocyanin formation in broom sorghum first internodes 总被引:1,自引:0,他引:1
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An action spectrum for anthocyanin formation in dark-grown broom sorghum (Sorghum bicolor Moench, cv Acme Broomcorn and cv Sekishokuzairai Fukuyama Broomcorn) seedlings was determined over the wavelength range from 260 to 735 nanometers. The action peaks were at 290, 650, 385, and 480 nanometers in descending order of height. The action of the 290-nanometer peak was not affected by subsequently given far red light, whereas those of the other three action peaks were nullified completely. The nullification of the 385-nanometer peak action by far red light was reversible. When an irradiation at these action peaks was followed by a phytochrome-saturating fluence of red light irradiation, the action of the 290-nanometer peak remained, whereas that of the 385-nanometer peak as well as those of the 650- and 480-nanometer peaks was masked by the action of the second irradiation. These findings suggested that the 290- and 385-nanometer action peaks involved different photoreceptors, the latter being phytochrome. The blue light-absorbing photoreceptor as reported to be a prerequisite for phytochrome action in milo sorghum was not found to exist in the broom sorghums.
The action spectrum deprived of the involvement of phytochrome was determined in the ultraviolet region by irradiating with far red light following monochromatic ultraviolet light. The spectrum had a single intense peak at 290 nanometers and no action at all at wavelengths longer than 350 nanometers.
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