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101.
This study determined the physical fitness component that contributes to improving and maintaining health status for each age group as well as quantifying the degree of the relationship between health status and physical fitness in middle-aged and elderly females. The participants were 2,371 females aged 30 to 69 years. Ten physical fitness tests and medical checkups were performed. The participants were divided into a healthy group and an unhealthy group according to health status. Multiple discriminant analysis was applied to the multivariate data. Correct discriminant probabilities of the multiple discriminant function to discriminate the healthy and unhealthy groups for females ranged from 63.0% to 77.5%. These results suggest that there is a relatively high relationship between health status and physical fitness level for middle-aged and elderly females. With each individual's discriminant score calculated by the obtained multiple discriminant function as the index of the degree of health, the Pearson's correlation coefficient of the discriminant score and the performance in each physical fitness test were calculated. The aging change from 30 to 69 years old was classified into four patterns according to the contribution. The result of this study is considered to be useful as objective data to prepare an exercise program considering the contribution of the physical fitness component of health status. 相似文献
102.
K Kimura S Kataoka A Nakamura T Takano S Kobayashi K Yamane 《Biochemical and biophysical research communications》1989,161(3):1273-1279
Cyclodextrin glucanotransferase (beta-CGTase) of alkalophilic Bacillus sp. #1011 degrades starch to mainly beta-cyclodextrin (beta-CD). This enzyme is considered to contain an extra-polypeptide in its COOH-terminal region in addition to its NH2-terminal domain which exhibits the starch-degrading activity. To analyze the functions of this extra-polypeptide in the beta-CGTase, two mutated enzymes, in which DNA regions encoding 10 or 13 amino acids from the COOH-terminus were deleted, were obtained. The mutated enzymes degraded starch to glucose, maltooligosaccharides and alpha-CD, in addition to beta-CD. Furthermore, the pH stability of the mutated enzymes in the alkaline pH range (pH 9-11) was reduced. 相似文献
103.
The distribution of mitochondria during conjugation of the ciliated protozoan Tetrahymena thermophila was surveyed using a mitochondrial stain and fluorescence in situ hybridization (FISH). When the mitochondria-specific stain, Mito-Tracker, was used, the majority of mitochondria were detected in the cortex; their distribution was not changed during conjugation. On the other hand, FISH using mitochondrial large subunit (LSU) rRNA as a probe showed an unusual distribution of signals during conjugation. Unexpectedly, the signals were detected throughout the cytoplasm of conjugating cells. These signals were not observed in pre-mating cells and in exconjugants. The cytosolic localization of mitochondrial rRNA was supported by northern blot analysis using post-mitochondrial RNA fraction at the later stages of conjugation. These observations suggest selective mitochondrial breakdown or transport of LSU rRNA into cytosol. The biological significance of the conjugation-specific appearance of the cytosolic mitochondrial rRNA is discussed. 相似文献
104.
105.
Mizukami Y Okamura T Miura T Kimura M Mogami K Todoroki-Ikeda N Kobayashi S Matsuzaki M 《Biochimica et biophysica acta》2001,1540(3):213-220
Cytokines and various cellular stresses are known to activate c-Jun N-terminal kinase-1 (JNK1), which is involved in physiological function. Here, we investigate the activation of JNK1 by oxidative stress in H9c2 cells derived from rat cardiomyocytes. H(2)O(2) (100 microM) significantly induces the tyrosine phosphorylation of JNK1 with a peak 25 min after the stimulation. The amount of JNK1 protein remains almost constant during stimulation. Immunocytochemical observation shows that JNK1 staining in the nucleus is enhanced after H(2)O(2) stimulation. To clarify the physiological role of JNK1 activation under these conditions, we transfected antisense JNK1 DNA into H9c2 cells. The antisense DNA (2 microM) inhibits JNK1 expression by 80% as compared with expression in the presence of the sense DNA, and significantly blocks H(2)O(2)-induced cell death. Consistent with the decrease in cell number, we detected condensation of the nuclei, a hallmark of apoptosis, 3 h after H(2)O(2) stimulation in the presence of the sense DNA for JNK1. The antisense DNA of JNK1 inhibits the condensation of nuclei by H(2)O(2). Under these conditions, the H(2)O(2)-induced phosphorylation of proteins with molecular masses of 55, 72, and 78 kDa is blocked by treatment with the antisense DNA for JNK1 as compared with the sense DNA for JNK1. These findings suggest that JNK1 induces apoptotic cell death in response to H(2)O(2), and that the cell death may be involved in the phosphorylations of 55, 72, and 78 kDa proteins induced by JNK1 activation. 相似文献
106.
Tadao Arinami Takeki Hirano Kimiko Kobayashi Yasuko Yamanouchi Hideo Hamaguchi 《Human genetics》1990,85(1):39-40
Summary The XmnI genotype at the apolipoprotein A-I locus was heterozygous in a boy with partial deletion of the long arm of chromosome 11, del(11)(q23.3qter). The apolipoprotein A-I gene, previously assigned to chromosome region 11q23q24, has been more specifically localized to 11q23 by excluding the region 11q24qter. 相似文献
107.
108.
Purification and properties of thiosulfate reductase from Desulfovibrio vulgaris, Miyazaki F 总被引:1,自引:0,他引:1
Thiosulfate reductase was purified to an almost homogeneous state from Desulfovibrio vulgaris, strain Miyazaki F, by ammonium sulfate precipitation, chromatography on DEAE-Toyopearl, Ultrogel AcA 34, and hydroxylapatite, and disc electrophoresis. The specific activity was increased 580-fold over the crude extract. The molecular weight was determined by gel filtration to be 85,000-89,000, differing from those reported for thiosulfate reductases from other Desulfovibrio strains. The enzyme had no subunit structure. When coupled with hydrogenase and methyl viologen, it stoichiometrically reduced thiosulfate to sulfite and sulfide with consumption of hydrogen. It did not reduce sulfite or trithionate. Cytochrome c3 was active as an electron donor. More than 0.75 mM thiosulfate inhibited the enzyme activity. o-Phenanthroline and 2,2'-bipyridine inhibited the enzyme and ferrous ion stimulated the reaction. 相似文献
109.
Tetsurou Muroi Takaaki Kokuzawa Yoshihiko Kihara Ryuichi Kobayashi Nobutaka Hirano Hideo Takahashi Mitsuru Haruki 《Applied microbiology and biotechnology》2013,97(9):4039-4048
Serine-type phage integrases catalyze unidirectional site-specific recombination between the attachment sites, attP and attB, in the phage and host bacterial genomes, respectively; these integrases and DNA target sites function efficiently when transferred into heterologous cells. We previously developed an in vivo site-specific genomic integration system based on actinophage TG1 integrase that introduces ~2-kbp DNA into an att site inserted into a heterologous Escherichia coli genome. Here, we analyzed the TG1 integrase-mediated integrations of att site-containing ~10-kbp DNA into the corresponding att site pre-inserted into various genomic locations; moreover, we developed a system that introduces ~10-kbp DNA into the genome with an efficiency of ~104 transformants/μg DNA. Integrations of attB-containing DNA into an attP-containing genome were more efficient than integrations of attP-containing DNA into an attB-containing genome, and integrations targeting attP inserted near the replication origin, oriC, and the E. coli “centromere” analogue, migS, were more efficient than those targeting attP within other regions of the genome. Because the genomic region proximal to the oriC and migS sites is located at the extreme poles of the cell during chromosomal segregation, the oriC–migS region may be more exposed to the cytosol than are other regions of the E. coli chromosome. Thus, accessibility of pre-inserted attP to attB-containing incoming DNA may be crucial for the integration efficiency by serine-type integrases in heterologous cells. These results may be beneficial to the development of serine-type integrases-based genomic integration systems for various bacterial species. 相似文献
110.
Induced penetration resistance is triggered by failed penetration attempts of nonpathogenic fungi. The resistance mechanism is an important nonhost reaction in plants that can block the invasion of filamentous pathogens such as fungi and oomycetes. However, it remains unclear whether the mechanical stimuli accompanying fungal penetration play a role in induced penetration resistance, whereas the perforation of the cell wall may provide significant stimuli to plant cells. Here, we used microneedles or biolistic bombardment to mimic fungal penetration pegs and a micromanipulation transfer technique of the bio-probe, a germling of Blumeria graminis hordei, to the wounded cells to demonstrate that microwounds derived from fungal penetration attempts may trigger induced penetration resistance in plant cells. When preinoculated with the nonpathogenic fungi Erysiphe pisi and Colletotrichum orbiculare, which were unable to penetrate a barley cell, the penetration of a bio-probe that was transferred by micromanipulation onto the same cell was completely blocked. Fungal penetration was essential to the triggering of induced penetration resistance because a penetration-peg-defective mutant of C. orbiculare completely lacked the ability to trigger resistance. The artificial microwounds significantly, but not completely, blocked the penetration of the bio-probe. Treatment with the actin polymerization inhibitor cytochalasin A or expression of the actin depolymerizing protein HvPro1 caused complete ablation of the induced penetration resistance triggered by either failed fungal penetration or artificial microwounds. These results strongly suggest that microwounding may trigger actin-dependent induced penetration resistance. Manipulation of induced penetration resistance may be a promising target to improve basic disease resistance in plants. 相似文献