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571.
Dissociation of Ca2+ mobilization from breakdown of phosphatidylinositol 4,5-bisphosphate in activated human platelets 总被引:3,自引:0,他引:3
M Kito H Narita H Takamura H J Park T Matsuura K Tanaka 《Journal of biochemistry》1986,99(4):1277-1280
The early breakdown of phosphatidylinositol 4,5-bisphosphate in human platelets stimulated by a threshold concentration of either collagen or thrombin was inhibited by 5 mM NaF through its inhibition of phospholipase C activity. However, 5 mM NaF did not inhibit Ca2+ mobilization due to the stimuli from internal stores, but it did inhibit the influx of extracellular Ca2+ through its suppression of thromboxane A2 formation. 相似文献
572.
573.
S Suzuki N Ozaki J Yoshida S Takamura Y Takeuchi S Kudo 《Journal of steroid biochemistry》1983,19(4):1419-1433
The possible role of Mg2+-HCO3-ATPase, carbonic anhydrase and several other enzymes in rat intestinal mucosa as mediators of the action of aldosterone has been examined. The small-intestinal tract was cut into seven segments, 15 cm each in length and the mucosa was scraped off, homogenized in 50 mM D-mannitol-2 mM Tris-HCl buffer (pH 7.1), differentially fractionated and a crude brush border was obtained. The mucosa from the colon and rectum was combined and used as the large-intestinal sample. Five days after the adrenalectomy, activities of brush border Mg2+-HCO3-ATPase and supernatant carbonic anhydrase from the upper small intestine decreased to about 60 and 40% of normal values, respectively. Activities of Na+-K+-ATPase, beta-glycerophosphatase and succinate dehydrogenase were all decreased. Two and 4 h after i.p. injection of aldosterone (40 micrograms/kg) to adrenalectomized rats, all enzyme activities increased except for Na+-K+-ATPase in the upper small intestine. In contrast, Mg2+-HCO-3-ATPase and carbonic anhydrase activities were unchanged 3 h after i.p. injection of dexamethasone (200 micrograms and 1 mg/kg). The activation of both Mg2+-HCO3-ATPase and carbonic anhydrase by a single injection of aldosterone was blocked by pretreatment with cycloheximide (1 mg/kg). These results suggest that aldosterone may induce the synthesis of enzyme proteins in the intestinal mucosa. 相似文献
574.
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
575.
576.
Y Takamura H Yagi K Hase T Yoneda M Maeda Y Akagi M Sato 《Biochemical and biophysical research communications》2001,285(2):387-392
We identified a novel gene encoding a new member of the DnaJ family, JDD1 (J domain of DnaJ-like-protein 1), from the rat. The cloned JDD1 cDNA is 1689 bp in size and its deduced amino acid sequence consists of 259 amino acid residues. Immunoblot analysis revealed that JDD1 protein is approximately 30 kDa in size. JDD1 has a J domain that is unique to the DnaJ family but lacks the G/F region (a region that is rich in the amino acids glycine and phenylalanine) and the zinc finger region (also known as the cysteine-rich region)-both characteristic to the DnaJ. JDD1 mRNA is expressed heterogeneously in vivo. In the central nervous system, JDD1 mRNA expression is confined to the germinal (ventricular and subventricular) zone where, except for cells situated deepest in the ventricular zone, neurons and glias are generated and then differentiate during the embryonic period. Expression of JDD1 mRNA in the subventricular zone persists after birth. In addition to the brain, its robust expression is notable in the liver, lung, cortex of the kidney, and several other tissues in the embryo. 相似文献
577.
The amplitude of circadian oscillations: temperature dependence, latitudinal clines, and the photoperiodic time measurement. 总被引:5,自引:0,他引:5
This paper develops several propositions concerning the lability of the amplitude of Drosophila circadian pacemakers. The first is that the amplitude of the pacemaker's motion, unlike its period, is markedly temperature-dependent. The second is that latitudinal variation in pacemaker amplitude (higher in the north) is responsible for two very different sets of observations on Drosophila circadian systems at successively higher latitudes. One of these is a cline in D. auraria's phase-shifting response to light, which steadily weakens in a succession of more northerly strains. The other, concerning D. littoralis in the very far north, is a cline in the rate at which eclosion activity becomes arrhythmic (the circadian rhythm damps out) in constant darkness; damping is faster in the north. The third proposition concerns a plausible selection pressure for the cline in pacemaker amplitude that we propose underlies the two directly observed clines. Two points are emphasized: (1) The amplitude of the pacemaker's daily oscillation declines as the duration of the entraining light pulse (photoperiod) is increased; and (2) the duration of the daily photoperiods throughout the breeding season is steadily increased as one moves toward the poles. Selection for conservation of pacemaker amplitude (during the breeding season) would produce the latitudinal cline we propose. The fourth, and final proposition is that since the amplitude of the pacemaker's daily motion responds systematically to change in photoperiod, amplitude is clearly one way--and a temperature-dependent way--in which insect circadian systems may sense seasonal change. These propositions concerning the temperature and latitude dependence of pacemaker amplitude may be relevant to a wider array of circadian pacemakers than Drosophila. 相似文献