65 research outputs found

    Obligatory roles of dopamine D1 receptors in the dentate gyrus in antidepressant actions of a selective serotonin reuptake inhibitor, fluoxetine

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    Depression is a leading cause of disability. Current pharmacological treatment of depression is insufficient, and development of improved treatments especially for treatment-resistant depression is desired. Understanding the neurobiology of antidepressant actions may lead to development of improved therapeutic approaches. Here, we demonstrate that dopamine D1 receptors in the dentate gyrus act as a pivotal mediator of antidepressant actions in mice. Chronic administration of a selective serotonin reuptake inhibitor (SSRI), fluoxetine, increases D1 receptor expression in mature granule cells in the dentate gyrus. The increased D1 receptor signaling, in turn, contributes to the actions of chronic fluoxetine treatment, such as suppression of acute stress-evoked serotonin release, stimulation of adult neurogenesis and behavioral improvement. Importantly, under severely stressed conditions, chronic administration of a D1 receptor agonist in conjunction with fluoxetine restores the efficacy of fluoxetine actions on D1 receptor expression and behavioral responses. Thus, our results suggest that stimulation of D1 receptors in the dentate gyrus is a potential adjunctive approach to improve therapeutic efficacy of SSRI antidepressants. © 2018, The Author(s).1

    Non-Collimatorによるシンチグラムの画像復元について

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    We have conducted an experiment on restoring scintigram images obtained without the use of collimators. Uncollimated images of liver slice phantoms filled with 99mTc were taken at a phantom-camera distance of 0 cm. The sensitivity under these conditions was about one thousand times higher than that using a low-energy high-resolution collimator. Uncollimated images were restored using unsharp masking in combination with spatial filtering. The unsharp masking process involved subtracting two images taken at phantom-camera distances of 0 and 2.3 cm to produce a difference image. The mean squared errors found were 0.56 for the uncollimated images, 0.54 for the images processed with the spatial filter only, and 0.53 for the images produced using unsharp masking followed by spatial filtering. Thus, the images processed using both unsharp masking and the spatial filter bore the closest resemblance to the actual images. Also, since this method was capable of revealing the shape of the phantom, it may already be usable for imaging large lesions, such as in lung perfusion scintigraphy.「久保直樹,花田博之著:Non-Collimatorによるシンチグラムの画像復元について, 北海道大学医療技術短期大学部紀要,8, p.151-156(1995)」の英訳

    Synthesis of Mo–Si–B in situ composites by mechanical alloying

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    In this study, the synthesis of Mo-Si-B multi-phase alloys, so-called in-situ composites, was attempted with the combination of mechanical alloying (MA) and spark plasma sintering (SPS) processes. MA was conducted with mixed powders of Mo, Si and B using a planetary ball mill under various milling conditions. MAed powders were characterized by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results obtained by XRD indicated that Mo-Si-B alloyed powders were successfully produced when elemental powders were milled at a higher milling energy. Vacuum heat treatments after the MA process promoted the formation of Mo-Si-B intermetallic phase in MAed powders. On the other hand, the MAed powders were successfully consolidated by a SPS technique, and as a result, sound compacts of Mo5SiB2-based composites were synthesized

    Average-case linear-time similar substring searching by the q-gram distance

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    In this paper we consider the problem of similar substring searching in the q-gram distance. The q-gram distance d(q)(x, y) is a similarity measure between two strings x and y defined by the number of different q-grams between them. The distance can be used instead of the edit distance due to its lower computation cost, O(|x| + |Y|) vs. O(|x||Y|). and its good approximation for the edit distance. However, if this distance is applied to the problem of finding all similar strings, in a long text t, to a given pattern p, the total computation cost is sometimes not acceptable. Ukkonen already proposed two fast algorithms: one with an array and the other with a tree. When "similar" means k or less in dq, their time complexities are O(|t|k + |P|) and O(|t| log k + |p|). respectively. In this paper, we propose two algorithms of average-case complexity O(|t| + |p|). although their worst-case complexities are still O(|t|k + |P|) and O(|t| log k + |p|). respectively. The linearity of the average-case complexity is analyzed under the assumption of random sampling of t and the condition that q is larger than a threshold. The algorithms exploit the fact that similar substrings in t are often found at very close positions if the beginning positions of the substrings are close. In the second proposed algorithm, we adopted a doubly-linked list supported by an array and a search tree to search for a list element in O(log k) time. Experimental results support their theoretical average-case complexities. (C) 2014 Elsevier B.V. All rights reserved

    Data on the effect of Prussian blue feeding on the radioactive cesium content of cow’s milk

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    This is a dataset on the effect of PB feeding on the radioactive cesium content of cow’milk. All data were acquired from two experiments carried out at Livestock research centre, Fukushima agricultural technology centre. Before determination, the samples were dried. Radioactive Cs concentrations in samples were determined by gamma ray spectrometry using a high-purity germanium semiconductor detector (GEM40-76, Seiko Co. Ltd., Tokyo, Japan) in experiment 1, and gamma ray spectrometry using a high-purity germanium semiconductor detector (GEM20-70, Seiko Co. Ltd.) in experiment 2. Raw data will be available by contacting corresponding author
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