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Shinpei Yoshimura Yasumasa Okamoto Atsuo Yoshino Makoto Kobayakawa Akihiko Machino Shigeto Yamawaki 《PloS one》2014,9(7)
Reappraisal is a well-known emotion regulation strategy. Recent neuroimaging studies suggest that reappraisal recruits both medial and lateral prefrontal brain regions. However, few studies have investigated neural representation of reappraisals associated with anticipatory anxiety, and the specific nature of the brain activity underlying this process remains unclear. We used functional magnetic resonance imaging (fMRI) to investigate neural activity associated with reappraisals of transient anticipatory anxiety. Although transient anxiety activated mainly subcortical regions, reappraisals targeting the anxiety were associated with increased activity in the medial and lateral prefrontal regions (including the orbitofrontal and anterior cingulate cortices). Reappraisal decreased fear circuit activity (including the amygdala and thalamus). Correlational analysis demonstrated that reductions in subjective anxiety associated with reappraisal were correlated with orbitofrontal and anterior cingulate cortex activation. Reappraisal recruits medial and lateral prefrontal regions; particularly the orbitofrontal and anterior cingulate cortices are associated with successful use of this emotion regulation strategy. 相似文献
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Tsukamoto Takashi; Nakanishi Hiromi; Uchida Hiroshi; Watanabe Satoshi; Matsuhashi Shinpei; Mori Satoshi; Nishizawa Naoko K. 《Plant & cell physiology》2009,50(1):48-57
The real-time translocation of iron (Fe) in barley (Hordeumvulgare L. cv. Ehimehadaka no. 1) was visualized using the positron-emittingtracer 52Fe and a positron-emitting tracer imaging system (PETIS).PETIS allowed us to monitor Fe translocation in barley non-destructivelyunder various conditions. In all cases, 52Fe first accumulatedat the basal part of the shoot, suggesting that this regionmay play an important role in Fe distribution in graminaceousplants. Fe-deficient barley showed greater translocation of52Fe from roots to shoots than did Fe-sufficient barley, demonstratingthat Fe deficiency causes enhanced 52Fe uptake and translocationto shoots. In the dark, translocation of 52Fe to the youngestleaf was equivalent to or higher than that under the light condition,while the translocation of 52Fe to the older leaves was decreased,in both Fe-deficient and Fe-sufficient barley. This suggeststhe possibility that the mechanism and/or pathway of Fe translocationto the youngest leaf may be different from that to the olderleaves. When phloem transport in the leaf was blocked by steamtreatment, 52Fe translocation from the roots to older leaveswas not affected, while 52Fe translocation to the youngest leafwas reduced, indicating that Fe is translocated to the youngestleaf via phloem in addition to xylem. We propose a novel modelin which root-absorbed Fe is translocated from the basal partof the shoots and/or roots to the youngest leaf via phloem ingraminaceous plants. 相似文献
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Using a microelectrophoresis instrument employing the Lazer-Zee system, the electrophoretic mobility of synaptic vesicles isolated from Guinea-pig brain cortex was measured under several conditions. The mobility was found to depend on both pH and ionic concentration of the solution. The surface of the synaptic vesicle was shown to be negatively charged under physiological conditions. The isoelectric point was observed at pH 4.0 in 0.01 M NaCl solution. Effects of divalent cations were examined and reversal of surface charge was observed in 0.1 M CaCl2 solution. Interaction of vesicles was also considered on the basis of the DLVO theory of colloid stability by using calculated values of surface charge density and surface potential of the synaptic vesicle. 相似文献
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Small unilamellar phosphatidylserine/phosphatidylcholine liposomes incubated on one side of planar phosphatidylserine bilayer membranes induced fluctuations and a sharp increase in the membrane conductance when the Ca2+ concentration was increased to a threshold of 3–5 mM in 100 mM NaCl, pH 7.4. Under the same ionic conditions, these liposomes fused with large (0.2 μm diameter) single-bilayer phosphatidylserine vesicles, as shown by a fluorescence assay for the mixing of internal aqueous contents of the two vesicle populations. The conductance behavior of the planar membranes was interpreted to be a consequence of the structural rearrangement of phospholipids during individual fusion events and the incorporation of domains of phosphatidylcholine into the Ca2+-complexed phosphatidylserine membrane. The small vesicles did not aggregate or fuse with one another at these Ca2+ concentrations, but fused preferentially with the phosphatidylserine membrane, analogous to simple exocytosis in biological membranes. Phosphatidylserine vesicles containing gramicidin A as a probe interacted with the planar membranes upon raising the Ca2+ concentration from 0.9 to 1.2 mM, as detected by an abrupt increase in the membrane conductance. In parallel experiments, these vesicles were shown to fuse with the large phosphatidylserine liposomes at the same Ca2+ concentration. 相似文献
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Al-Ghaithi F El-Ridi MR Adeghate E Amiri MH 《Molecular and cellular biochemistry》2004,261(1-2):143-149
Diabetes mellitus is one of the most common endocrine diseases. In UAE many traditional plants such as the Citrullus colocynthis (Handal) are used as antidiabetic remedies. The aim of this study was to examine the effect of the aqueous extract of the seed of C. colocynthis on the biochemical parameters of normal and streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced by a single intraperitoneal (60 mg/kg body wt1) injection of STZ. Normal and diabetic rats were fed with the plant extract daily by oral intubation for 2 weeks. Blood sample were collected at the beginning and end of the experiment for the measurement of biochemical parameters. The plasma level of alanine aminotranferase (ALT), alkaline phosphatase (ALP), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), lactic dehydrogenase (LDH) increased significantly after the onset of diabetes. Oral administration of the plant extract reduced the plasma level of AST and LDH significantly. However, the plant extract failed to reduce the increased blood level of GGT and ALP in diabetic rats. Blood urea nitrogen (BUN) increased significantly after the onset of diabetes. No significant difference was observed in the blood creatinine, K+, Na+, Ca2+ and P levels of normal and diabetic rats. The plant extract did not have any effect on BUN level, however, it caused an increase in the level of K+, Na+ in diabetic rats. In conclusion, oral administration of the aqueous extract of the C. colocynthis can ameliorate some of the toxic effects of streptozotocin. 相似文献