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861.
Regulation of Polyphosphoinositide Metabolism in Pea Plasma Membranes by Elicitor and Suppressor from a Pea Pathogen, Mycosphaerella pinodes 总被引:1,自引:0,他引:1
Toyoda Kazuhiro; Shirashi Noriaki; Yoshioka Hirofumi; Yamada Tetsuji; Ichinose Yuki; Oku Hachiro 《Plant & cell physiology》1992,33(4):445-452
Effects of the elicitor and the suppressor from a pea pathogen,Mycosphaerella pinodes, on polyphosphoinositide metabolism inpea plasma membranes were examined in vitro. Lipid phosphorylationin the isolated pea plasma membrane was drastically stimulatedby the elicitor, but markedly inhibited by the suppressor. Asimilar inhibitory effect was observed by the treatment withorthovanadate or K-252a that blocked pisatin production inducedby the elicitor. Neomycin, an aminoglycoside antibiotic thatinteracts with the polyphosphoinositide metabolism, also affectedthe lipid phosphorylation in vitro and blocked the elicitor-inducedaccumulation of pisatin in vivo. These results suggest thatrapid changes of polyphosphoinositide metabolism in pea plasmamembranes is one of indispensable processes during the elicitationof defense responses. (Received January 22, 1992; Accepted March 23, 1992) 相似文献
862.
Background
The hypothalamic-pituitary-adrenocortical (HPA) axis and sympathetic adrenomedullary (SAM) system are the major stress-response pathways. Plasma adrenocorticotropic hormone (ACTH) represents HPA axis activity, while plasma catecholamines are used as markers of the SAM system. Salivary alpha amylase (AA), chromogranin A (CgA), and immunoglobulin A (IgA) are candidate markers of stress activation, although their role has not been established. The Uchida-Kraepelin (U-K) test is a questionnaire that requires intense concentration and effort, and has been used as a tool to induce mental stress. However, it is not clear whether or not the test is effective as a psychological/mental stressor. 相似文献863.
Ayumu Yamashita Yuki Sakai Takashi Yamada Noriaki Yahata Akira Kunimatsu Naohiro Okada Takashi Itahashi Ryuichiro Hashimoto Hiroto Mizuta Naho Ichikawa Masahiro Takamura Go Okada Hirotaka Yamagata Kenichiro Harada Koji Matsuo Saori C. Tanaka Mitsuo Kawato Kiyoto Kasai Nobumasa Kato Hidehiko Takahashi Yasumasa Okamoto Okito Yamashita Hiroshi Imamizu 《PLoS biology》2020,18(12)
Many studies have highlighted the difficulty inherent to the clinical application of fundamental neuroscience knowledge based on machine learning techniques. It is difficult to generalize machine learning brain markers to the data acquired from independent imaging sites, mainly due to large site differences in functional magnetic resonance imaging. We address the difficulty of finding a generalizable marker of major depressive disorder (MDD) that would distinguish patients from healthy controls based on resting-state functional connectivity patterns. For the discovery dataset with 713 participants from 4 imaging sites, we removed site differences using our recently developed harmonization method and developed a machine learning MDD classifier. The classifier achieved an approximately 70% generalization accuracy for an independent validation dataset with 521 participants from 5 different imaging sites. The successful generalization to a perfectly independent dataset acquired from multiple imaging sites is novel and ensures scientific reproducibility and clinical applicability.Biomarkers for psychiatric disorders based on neuroimaging data have yet to be put to practical use. This study overcomes the problems of inter-site differences in fMRI data by using a novel harmonization method, thereby successfully constructing a generalizable brain network marker of major depressive disorder across multiple imaging sites. 相似文献
864.
Isolation of a cytotoxin from L-form Salmonella typhimurium 总被引:2,自引:0,他引:2
Eiji Kita Noriaki Kamikaidou Akira Nakano Shuzo Kashiba 《FEMS microbiology letters》1993,109(2-3):179-184
Abstract A cytotoxin protein was isolated from the sodium dodecyl sulphate (SDS)-solubilized extract of the stable L forms of Salmonella typhimurium by ion-retardation chromatography, ion-exchange chromatography, isoelectric focusing and gel filtration. The purified toxin, with a molecular mass of 32 kDa and with isoelectric point of 6.4, was thermolabile and trypsin-sensitive. Against mouse macrophages, its cytolytic effect was detectable in vitro at concentrations higher than 0.7 μg/ml, with a complete lysis obtained at 5 μg/ml. In contrast, it stimulated C3H/HeJ macrophages in the dose range of 0.1–0.5 μg/ml to allow the cell to respond to endotoxin, resulting in the significant production of tumor necrosis factor α. By Northern blot analysis, this effect was detectable at a dose as low as 0.01 μg/ml. These findings suggest that the transformation of bacillary S. typhimurium into L forms in vivo may induce alterations in host resistance against murine typhoid. 相似文献
865.
Tatsuya Sakakibara Seiji Murakami Noriaki Hattori Moto-o Nakajima Kazuhiro Imai 《Analytical biochemistry》1997,250(2):157
A novel and effective treatment of biological samples with a combination of adenosine phosphate deaminase and apyrase was developed for reducing extracellular ATP, which has been a major problem encountered in improving the sensitivity of assays for intracellular ATP by the firefly luciferin–luciferase (L-L) method. Under the enzymatic reaction conditions, ATP and the related adenosine derivatives were converted to IMP, which are not active to the L-L system. In the model system (3.2 × 10−8mATP in 1% yeast extract solution) the treatment with adenosine phosphate deaminase resulted in the reduction of ATP to 1.3 × 10−11m, and the concomitant use of apyrase lowered the concentration to 3.3 × 10−13m. The treatment (0.05 U/ml of adenosine phosphate deaminase and apyrase) was applied to the detection of bacteria in broth by the L-L method, affording the detection of 42 colony-forming unit (CFU)/ml ofEscherichia coliand 10 CFU/ml ofStaphylococcus aureusin the broth. 相似文献