302 research outputs found

    Attenuation of guanine oxidation via DNA-mediated electron transfer in a crowded environment using small cosolutes

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    Guanine oxidation induced by photoirradiation on a pyrene-modified oligonucleotide was investigated under molecular crowding using small cosolutes such as glycerol. The efficiency of guanine photooxidation was suppressed in accordance with the increase in the concentration of glycerol. The results of photooxidation experiments using fully matched and mismatched DNA showed that guanine decomposition was mainly caused by DNA-mediated electron transfer (ET) in glycerol mixed solutions, as well as in diluted aqueous buffer solutions. Multiple factors can contribute to the suppression of guanine oxidation in crowded environments. However, our experimental results indicated that the attenuation of the DNA-mediated ET process suppressed guanine oxidation. On the other hand, experiments using ethylene glycol showed that guanine decomposition efficiency varies depending on the surrounding solvent. These results suggested that changes in the characteristics of the surrounding medium affect the DNA fluctuation, dominating DNA-mediated ET

    Midazolam suppresses interleukin-1β-induced interleukin-6 release from rat glial cells

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    <p>Abstract</p> <p>Background</p> <p>Peripheral-type benzodiazepine receptor (PBR) expression levels are low in normal human brain, but their levels increase in inflammation, brain injury, neurodegenerative states and gliomas. It has been reported that PBR functions as an immunomodulator. The mechanisms of action of midazolam, a benzodiazepine, in the immune system in the CNS remain to be fully elucidated. We previously reported that interleukin (IL)-1β stimulates IL-6 synthesis from rat C6 glioma cells and that IL-1β induces phosphorylation of inhibitory kappa B (IκB), p38 mitogen-activated protein (MAP) kinase, stress-activated protein kinase (SAPK)/c-<it>Jun </it>N-terminal kinase (JNK), extracellular signal-regulated kinase 1/2, and signal transducer and activator of transcription (STAT)3. It has been shown that p38 MAP kinase is involved in IL-1β-induced IL-6 release from these cells. In the present study, we investigated the effect of midazolam on IL-1β-induced IL-6 release from C6 cells, and the mechanisms of this effect.</p> <p>Methods</p> <p>Cultured C6 cells were stimulated by IL-1β. IL-6 release from C6 cells was measured using an enzyme-linked immunosorbent assay, and phosphorylation of IκB, the MAP kinase superfamily, and STAT3 was analyzed by Western blotting.</p> <p>Results</p> <p>Midazolam, but not propofol, inhibited IL-1β-stimulated IL-6 release from C6 cells. The IL-1β-stimulated levels of IL-6 were suppressed by wedelolactone (an inhibitor of IκB kinase), SP600125 (an inhibitor of SAPK/JNK), and JAK inhibitor I (an inhibitor of JAK 1, 2 and 3). However, IL-6 levels were not affected by PD98059 (an inhibitor of MEK1/2). Midazolam markedly suppressed IL-1β-stimulated STAT3 phosphorylation without affecting the phosphorylation of p38 MAP kinase, SAPK/JNK or IκB.</p> <p>Conclusion</p> <p>These results strongly suggest that midazolam inhibits IL-1β-induced IL-6 release in rat C6 glioma cells via suppression of STAT3 activation. Midazolam may affect immune system function in the CNS.</p

    Characterization of Tunable Magnetic Sensor Using Bias Magnetic Field of a Hard Magnetic Film Magnetized by Pulsed-Magnetic Field

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    A tunable magnetoresistance (MR) sensor with variable sensitivity and measuring range is fabricated and characterized. The sensor has been fabricated using a combination of Ni-Fe soft magnetic film, Fe-Co-Sm hard magnetic film. The sensor is placed in a magnetizing coil for the process of magnetizing the hard magnetic film. The sensitivity and the measuring range of the sensor are tuned by bias magnetic field produced by the magnetic poles of the hard magnetic film. The sensitivity change was about 60%, and the measuring range change was about 30% in the tunable MR sensor from the experimental results. The bias magnetic field is controlled by changing amplitude of the pulsed magnetic field in the magnetizing for the hard magnetic film. The control power for one time tuning is about 18 mu Wh.ArticleIEEE TRANSACTIONS ON MAGNETICS. 49(7):3854-3857 (2013)journal articl

    近赤外線スペクトロスコピィを用いた成人期注意欠如・多動症の前頭前野における血液動態反応の低下

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    AIM: Recent developments in near-infrared spectroscopy (NIRS) have enabled non-invasive clarification of brain functions in psychiatric disorders. In pediatric attention-deficit hyperactivity disorder (ADHD), reduced prefrontal hemodynamic responses have been observed with NIRS repeatedly. However, there are few studies of adult ADHD by multi-channel NIRS. Therefore, in this study, we used multi-channel NIRS to examine the characteristics of prefrontal hemodynamic responses during the Stroop Color-Word Task (SCWT) in adult ADHD patients and in age- and sex-matched control subjects. METHODS: Twelve treatment-naïve adults with ADHD and 12 age- and sex-matched healthy control subjects participated in the present study after giving consent. We used 24-channel NIRS to measure the oxygenated hemoglobin (oxy-Hb) changes at the frontal lobes of participants during the SCWT. We compared the oxy-Hb changes between adults with ADHD and control subjects by t-tests with Bonferroni correction. RESULTS: During the SCWT, the oxy-Hb changes observed in the ADHD group were significantly smaller than those in the control group in channels 11, 16, 18, 21, 22, 23, and 24, corresponding to the prefrontal cortex. At channels 16, 21, 23, and 24 of the ADHD group, there were negative correlations between the symptomatic severity and the oxy-Hb changes. CONCLUSION: The present study suggests that adults with ADHD have reduced prefrontal hemodynamic response as measured by NIRS.博士(医学)・乙第1422号・平成30年11月30日© 2018 The Authors. Psychiatry and Clinical Neurosciences © 2018 Japanese Society of Psychiatry and NeurologyThis is the pre-peer reviewed version of the following article: [https://onlinelibrary.wiley.com/doi/full/10.1111/pcn.12643], which has been published in final form at [https://doi.org/10.1111/pcn.12643]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions

    Anode Properties of Ru-Coated Si Thick Film Electrodes Prepared by Gas-Deposition

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    Thick film electrodes consisting of Ru and Ru-coated Si particles were fabricated by a gas-deposition method and evaluated their electrochemical properties of anodes for Li rechargeable battery. The discharge capacity of the Ru electrode at 1000th cycle is approximately 400 mAh g-1. The result showed that the electrode reaction is based on the redox reaction of RuO2 which was formed on the Ru surface during the charge-discharge processes. By coating Si particles with Ru using an electroless deposition technique, we obtained an electrode with remarkable discharge capacity of 570 mAh g-1 at 1000th cycle. The reason for the improvement in the electrode performance appears to result from the fact that the Ru electrode exhibits excellent cycleability itself and the Ru coated on Si reduces the stress generated by the immense volumetric changes occurring in the Si particles

    Mg2Ge/Si Composite Electrodes Prepared by Gas-Deposition as Anodes for Lithium Rechargeable Battery

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    Mg2Ge/Si composite electrodes were prepared by a gas-deposition (GD) method and evaluated their electrochemical properties of anodes for Li rechargeable battery. The discharge capacity of the Mg2Ge/Si composite electrodes increased in comparison with that of Mg2Ge GD-film electrode. Among them, the Mg2Ge/Si composite electrode with 30 wt% Si content exhibited good cycle stability, which is 603 mAh g-1 after 200 cycles. At this composition of composite, each Si particle was surrounded with Mg2Ge layer, and the Mg2Ge layer appears to be easy to release the stress generated in the Si particle at Li insertion-extraction because Mg2Ge is more ductile than Si. Thus, we succeeded to develop the electrode which can take advantage of both high capacity of Si and good cyclability of Mg2Ge

    Anode Properties of Cu-Coated Si Thick Film Electrodes Prepared by Electroless Deposition and Gas-Deposition

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    Thick film electrodes of Cu-coated Si particles were fabricated by an electroless deposition and a successive gas-deposition, and were evaluated their electrochemical properties as an anode of Li-ion battery. The discharge capacity and its retention at the 1000th cycle were 570 mAh g-1 and 61%. The excellent cycle life performance is attributed to an enhanced electrical conductivity due to the Cu-coating and a reversible conversion reaction between Li and Cu2O which was formed on the Cu surface. The high capacity retention is caused by a high fracture toughness of the coated Cu which can effectively relax a stress induced by volume expansion of Si as a buffer matrix

    RELATIONSHIP BETWEEN THE SHEAR ELASTIC MODULUS AND PASSIVE FORCE IN POSTERIOR SHOULDER CAPSULES: A CADAVERIC STUDY

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    Although shear wave elastography (SWE) has been used to indirectly measure passive force in muscle tissues, it is unknown whether SWE can be utilized to evaluate passive force in capsule tissues. This study investigated the relationship between the shear elastic modulus and passive force in posterior shoulder capsules using SWE. Four middle and four inferior posterior shoulder capsules were dissected from four fresh-frozen cadavers. Passive force (0-400 g in 25-g increments) was applied to each capsule, and elasticity was measured simultaneously using SWE. The relationship between elasticity and passive capsule force was highly linear for all tested capsules (coefficients of determination range: 0.853-0.963). SWE is a valid and useful method of evaluating indirectly and noninvasively the passive force of the posterior shoulder capsules

    Modulation of Emotion by Cognitive Activity

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    While emotions themselves are beneficial for our survival, they are also the targets to be regulated appropriately to adapt to social environments. Previous studies have demonstrated that cognitive strategies such as cognitive reappraisal and expressive suppression can effectively enhance and attenuate emotions. Such cognitive strategies of emotion regulation are based on cortical modulation of sub-cortical emotion-related brain regions. Though in the prior studies emotion regulation was conducted in parallel with or after the emotion elicitation, a series of our studies showed that prior cognitive activities can automatically and unintentionally attenuate subsequent emotional responses. In this article, after reviewing the previous findings about emotion regulation, we introduce our empirical findings showing that cognitive activities where the neural system of emotion regulation would be recruited can unintentionally and automatically dampen psychological and physiological emotional responses. Finally, we propose possible neural mechanisms underlying modulation of emotion by cognitive activity

    Synthesis and chiral recognition ability of helical polyacetylenes bearing helicene pendants

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    International audienceNovel polyacetylenes bearing an optically active or racemic [6]helicene unit as the pendant groups directly bonded to the main-chain (poly-1s) were prepared by the polymerization of the corresponding acetylenes (1-rac, 1-P, and 1-M) with a rhodium catalyst. The optically active polyacetylenes (poly-1-P and poly-1-M) formed a preferred-handed helical conformation biased by the optically active helicene pendants, resulting in the induced circular dichroism (ICD) in their π-conjugated polymer backbone regions. The optically active helical polymers, when employed as an enantioselective adsorbent, showed a high chiral recognition ability towards racemates, such as the monomeric [6]helicene and 1,1’-binaphthyl analogues, and enantioselectively adsorbed one of the enantiomers
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