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81.
Kaori Yamanaka Hiroi Tomioka Shingo Kawasaki Yumiko Noda Bun Yamagata Akira Iwanami Masaru Mimura 《PloS one》2014,9(7)
In a previous study, we succeeded in improving the spatial working memory (WM) performance in healthy young persons by applying transcranial magnetic stimulation (TMS) to the parietal cortex and simultaneously measuring the oxygenated hemoglobin (oxy-Hb) level using near-infrared spectroscopy (NIRS). Since an improvement in WM was observed when TMS was applied to the right parietal cortex, the oxy-Hb distribution seemed to support a model of hemispheric asymmetry (HA). In the present study, we used the same study design to evaluate healthy elderly persons and investigated the effect of TMS on WM performance in the elderly, comparing the results with those previously obtained from young persons. The application of TMS did not affect WM performance (both reaction time and accuracy) of 38 elderly participants (mean age = 72.5 years old). To investigate the reason for this result, we conducted a three-way ANOVA examining oxy-Hb in both young and elderly participants. For the right parietal TMS site in the elderly, TMS significantly decreased the oxy-Hb level during WM performance; this result was the opposite of that observed in young participants. An additional three-way ANOVA was conducted for each of the 52 channels, and a P value distribution map was created. The P value maps for the young participants showed a clearly localized TMS effect for both the WM and control task, whereas the P map for the elderly participants showed less significant channels and localization. Further analysis following the time course revealed that right-side parietal TMS had almost no effect on the frontal cortex in the elderly participants. This result can most likely be explained by age-related differences in HA arising from the over-recruitment of oxy-Hb, differentiation in the parietal cortex, and age-related alterations of the frontal-parietal networks. 相似文献
82.
S Shimura T Okubo S Maeda T Aoki M Tomioka Y Shindo T Takishima K Umeya 《Biorheology》1983,20(5):677-683
We studied the effects of expectorants (mucolytic agents) in vivo on the relaxation behavior of sputum viscoelasticity. Seven female and thirty-three male patients (56.8 +/- 19.3 yrs, range: 21 to 82 years old) with a chronic pulmonary disease except bronchial asthma were studied. They were randomly put into the control group or a group which would be given oral treatments with an expectorant for a week after a one week washout period. The groups were as follows: Group I (n = 8), control; Group II (n = 7), Bromhexine hydrochloride 24 mg per day; Group III (n = 10), Ambroxol 90 mg per day; Group IV (n = 9) alpha - Chymotrypsin buccle 100 ch.u. per day; Group V (n = 6), Serratiopeptidase 30 mg per day. In Groups IV & V, frequency dependence of sputum viscoelasticity at the range of omega = 10(-3) to 10(0) rad.sec-1 were clearly changed after the treatments, and the magnitude of the relaxation and its main relaxation time were significantly increased. On the other hand, in Groups I, II & III, no significant changes of the frequency dependences were observed. These findings suggest that proteolytic enzymes administered orally work on the molecular structure of sputum, and break down their linkages between subunits of the structure. 相似文献
83.
Haruaki Ninomiya Takashi Taniguchi Masakuni Kameyama Motohatsu Fujiwara 《Journal of neurochemistry》1988,51(4):1111-1117
We examined the effects of in vivo hypoxia (10% O2/90% N2) on the gamma-aminobutyric acid (GABA)/benzodiazepine receptors and on glutamic acid decarboxylase (GAD) activity in the rat brain. Male Wistar rats were exposed to a mixture of 10% O2 and 90% N2 in a chamber for various periods (3, 6, 12, and 24 h). The control rats were exposed to room air. The brain regions examined were the cerebral cortex, striatum, hippocampus, and cerebellum. GABA and benzodiazepine receptors were assessed using [3H]muscimol and [3H]flunitrazepam, respectively. Compared with control values, GAD activity was decreased significantly following a 6-h exposure to hypoxia in all four regions studied. On the other hand, the numbers of both [3H]muscimol and [3H]flunitrazepam binding sites were increased significantly. The increase in receptor number tended to return to control values after 24 h. Treatment of the membrane preparations with 0.05% Triton X-100 eliminated the increase in the binding capacity. These results may represent an up-regulation of postsynaptically located GABA/benzodiazepine receptors corresponding to the impaired presynaptic activity under hypoxia. 相似文献
84.
T Yamada K Tomioka M Horie Y Sakurai H Nagaoka T Mase 《Biochemical and biophysical research communications》1991,176(2):781-785
We investigated the effects of YM264, WEB2086, methylprednisolone and ticlopidine on puromycin-induced nephropathy in the rat. Puromycin produces marked proteinuria, hypercholesterolemia, and hypoalbuminemia. The structurally differing PAF antagonists YM264 and WEB2086 inhibited proteinuria and improved hypercholesterolemia and hypoalbuminemia. Methylprednisolone also exhibited a beneficial effect on these variables. However, ticlopidine, a platelet inhibitor, showed no inhibitory effect on nephropathy. These results indicate that PAF may play a major role in puromycin-induced nephropathy in the rat, and that PAF antagonists may prove of therapeutic value in the treatment of nephropathy in humans. 相似文献
85.
Relationship between the susceptibility of various bacteria to active oxygen species and to intracellular killing by macrophages 总被引:8,自引:0,他引:8
The susceptibilities of six micro-organisms to active oxygen species generated in the xanthine oxidase-mediated bactericidal system were as follows: Escherichia coli 81 greater than or equal to Listeria monocytogenes EGD greater than or equal to Salmonella typhimurium HKB-1 greater than or equal to Staphylococcus aureus Smith much greater than Mycobacterium tuberculosis H37Rv approximately equal to Candida albicans NIH A207 (the last two organisms were essentially resistant to this system). The H2O2-Fe-mediated halogenation system exhibited a higher microbicidal activity. When the micro-organisms were compared for their sensitivity to bactericidal activity of resident mouse peritoneal macrophages (M phi s), C. albicans, Staph. aureus and E. coli were killed rapidly, whereas M. tuberculosis, L. monocytogenes and S. typhimurium were more resistant. In tests for the ability to trigger an oxidative burst in mouse peritoneal M phi s (as measured by chemiluminescence), Staph. aureus showed the highest activity followed by the other organisms in the following order: C. albicans greater than E. coli greater than L. monocytogenes congruent to M. tuberculosis. S. typhimurium exhibited no triggering activity. The high susceptibility of Staph. aureus and E. coli to M phi bactericidal activity, and the partial resistance of L. monocytogenes and M. tuberculosis, correlated with their susceptibility to active oxygen and the H2O2-Fe-mediated halogenation reaction. 相似文献
86.
The complete nucleotide sequence of a 16S ribosomal RNA gene from a blue-green alga, Anacystis nidulans 总被引:34,自引:0,他引:34
The complete nucleotide sequence of a 16S ribosomal RNA gene from a blue-green alga, Anacystis nidulans, has been determined. Its coding region is estimated to be 1,487 base pairs long, which is nearly identical to those reported for chloroplast 16S rRNA genes and is about 4% shorter than that of the Escherichia coli gene. The 16S rRNA sequence of A. nidulans has 83% homology with that of tobacco chloroplast and 74% homology with that of E. coli. Possible stem and loop structures of A. nidulans 16S rRNA sequences resemble more closely those of chloroplast 16S rRNAs than those of E. coli 16S rRNA. These observations support the endosymbiotic theory of chloroplast origin. 相似文献
87.
Haruo Ohnishi Hiroshi Kosuzume Yutaka Kitamura Kazuo Yamaguchi Masahiro Nobuhara Yasuo Suzuki Shoji Yoshida Hisao Tomioka Akira Kumagai 《Prostaglandins & other lipid mediators》1980,20(4):655-666
To elucidate the chemical structure of slow-reacting substance of anaphylaxis from rat (SRS-Arat), SRS-Arat were purified by the method of Orange with modification using DEAE-Sephadex A-25 chromatography. Ultraviolet absorption spectrum of purified SRS-Arat indicated the presence of conjugated triene. Arylsulfatase B degradation products and HCl degradation products were subjected to analysis by a gas chromatography and mass spectrometry and a thin layer chromatography. Products obtained by arylsulfatase B catalysis contained 5,6-dihydroxy-7,9,11,14-eicosatetraenoic acid. HCl degradation products showed the presence of glycine, glutamic acid and cysteic acid. Furthermore, the analysis of anhydrous hydrazine degradation products of SRS-Arat and of HCl hydrolyzed products of dinitrophenylated SRS-Arat revealed the presence of glycine at C-terminal and glutamic acid at N-terminal. The study of the substrate specificity of arylsulfatase B against various materials including SRS-Arat suggested the presence of sulfone in SRS-Arat. The molecular ion peak of SRS-Arat sodium salt was observed at m/e 680 in field desorption mass spectrum of SRS-Arat.On the basis of these data, we identified the structure of SRS-Arat as [γ-glutamyl-4(5-hydroxy-7,9,11,14-eicosatetraenoic acid-6-yl)-4,4-dioxocysteinyl] glycine. 相似文献
88.
J Nakagawa S Tamaki S Tomioka M Matsuhashi 《The Journal of biological chemistry》1984,259(22):13937-13946
Dual enzyme activities for the biosynthesis of peptidoglycan of the cell wall are located in major higher molecular weight penicillin-binding proteins (PBP) of Escherichia coli. Each of these proteins catalyzes the two successive final reactions in the synthesis of cross-linked peptidoglycan from the precursor N-acetylglucosaminyl-N-acetylmuramyl peptide linked to undecaprenol diphosphate; namely, the transglycosylation that extends the glycan chain and the penicillin-sensitive DD-transpeptidation that cross-links the glycan chains through two peptide side chains. Both transglycosylation and transpeptidation catalyzed by PBP-1Bs represent de novo synthesis of cross-linked peptidoglycan. Under appropriate conditions, about 25% cross-linkage was observed during the reaction, the main reaction product supposedly being a regularly cross-linked network of peptidoglycan. The two domains for the transglycosylase and transpeptidase activities were found to be located on a 50-kDa portion of the PBP-1Bs, which are about 90 kDa. Gene recombination experiments indicated that the transglycosylase domain is located upstream, i.e. on the N-terminal side of the transpeptidase domain, suggesting that the gene for these bifunctional peptides may have been formed by fusion of the genes for transglycosylase and transpeptidase that were previously located separately on the chromosome in this order. 相似文献
89.
90.
PSK, a protein-bound polysaccharide isolated from the basidiomycete Coriolus vesicolor (Fr.) Quél. was examined with regard to its effects of macrophage (M phi) oxygen metabolism in mice, a function important for the expression of M phi antimicrobial activity. The O2(-)-producing ability and chemiluminescence (CL) of host peritoneal M phi s in response to phorbol myristate acetate were markedly elevated by preinjection of PSK (1 or 5 mg per mouse intraperitoneally) around 4-7d before M phi-harvest. The enhanced O2(-)-producing ability due to PSK injection persisted much longer than the enhanced CL, indicating a discrepancy in regulation of generation of active oxygen species such as O2-, H2O2, OH, and 1O2. Daily injections of PSK (1 mg per injection) from 10 to 4d before M phi harvest did not increase the efficacy of PSK over that given by a single 1 mg injection. When PSK (5 mg) was given intraperitoneally to mice in a single injection 10, 7 or 4d before the intravenous Listeria monocytogenes inoculation, a similar increase in the host resistance to the bacteria was noted regardless of the timing of the injection. Multiple PSK injections fron 10 to 4d before the infection also enhanced the host resistance, to the same degree. Therefore, PSK is thought to augment the host resistance to certain intracellular parasites including L. monocytogenes at least to some extent by enhancing oxygen metabolism of the host M phi. 相似文献