基本情報
研究キーワード
32研究分野
7経歴
10-
2022年4月 - 現在
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2016年1月 - 現在
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2013年9月 - 2015年12月
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2013年9月 - 2015年12月
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2008年6月 - 2013年8月
学歴
1-
- 1987年
委員歴
3-
2021年9月
受賞
2-
1999年
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1993年
論文
212-
Molecular neurobiology 2024年4月27日It is established that neurogenesis of dentate gyrus is increased after ischemic insult, although the regulatory mechanisms have not yet been elucidated. In this study, we focused on Ezh2 which suppresses gene expression through catalyzing trimethylation of lysine 27 of histone 3. Male gerbils were injected with adeno-associated virus (AAV) carrying shRNA targeting to Ezh2 into right dentate gyrus 2 weeks prior to forebrain ischemia. One week after ischemia, animals were injected with thymidine analogue to label proliferating cells. Three weeks after ischemia, animals were killed for histological analysis. AAV-mediated knockdown of Ezh2 significantly decreased the ischemia-induced increment of proliferating cells, and the proliferated cells after ischemia showed significantly longer migration from subgranular zone (SGZ), compared to the control group. Furthermore, the number of neural stem cells in SGZ significantly decreased after ischemia with Ezh2 knockdown group. Of note, Ezh2 knockdown did not affect the number of proliferating cells or the migration from SGZ in the non-ischemic condition. Our data showed that, specifically after ischemia, Ezh2 knockdown shifted the balance between self-renewal and differentiation toward differentiation in adult dentate gyrus.
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Cell reports 42(11) 113432-113432 2023年11月13日The action observation network (AON) has been extensively studied using short, isolated motor acts. How activity in the network is altered when these isolated acts are embedded in meaningful sequences of actions remains poorly understood. Here we utilized intracranial electrocorticography to characterize how the exchange of information across key nodes of the AON-the precentral, supramarginal, and visual cortices-is affected by such embedding and the resulting predictability. We found more top-down beta oscillation from precentral to supramarginal contacts during the observation of predictable actions in meaningful sequences compared to the same actions in randomized, and hence less predictable, order. In addition, we find that expectations enabled by the embedding lead to a suppression of bottom-up visual responses in the high-gamma range in visual areas. These results, in line with predictive coding, inform how nodes of the AON integrate information to process the actions of others.
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Brain stimulation 2023年9月28日BACKGROUND: We previously found that vagus nerve stimulation (VNS) strengthened stimulus-evoked activity in the superficial layer of the sensory cortex but not in the deep layer, suggesting that VNS altered the balance between the feedforward (FF) and feedback (FB) pathways. Band-specific oscillatory activities in the cortex could serve as an index of the FF-FB balance, but whether VNS affects cortical oscillations along sensory pathways through neuromodulators remains unclear. HYPOTHESIS: VNS modulates the FF-FB balance through the cholinergic and noradrenergic systems, which modulate stimulus gain in the cortex. METHODS: We investigated the effects of VNS using electrocorticography in the auditory cortex of 34 Wistar rats under general anesthesia while presenting click stimuli. In the time-frequency analyses, the putative modulation of the FF and FB pathways was estimated using high- and low-frequency power. We assessed, using analysis of variance, how VNS modulates auditory-evoked activities and how the modulation changes with cholinergic and noradrenergic antagonists. RESULTS: VNS increased auditory cortical evoked potentials, consistent with results of our previous work. Furthermore, VNS increased auditory-evoked gamma and beta powers and decreased theta power. Local administration of cholinergic antagonists in the auditory cortex selectively disrupted the VNS-induced increase in gamma and beta power, while noradrenergic antagonists disrupted the decrease in theta power. CONCLUSIONS: VNS might strengthen the FF pathway through the cholinergic system and attenuate the FB pathway through the noradrenergic system in the auditory cortex. Cortical gain modulation through the VNS-induced neuromodulatory system provides new mechanistic insights into the effect of VNS on auditory processing.
MISC
383-
脳循環代謝 11(1) 12-13 1999年7月propentofylline(PPF)が,虚血耐性に及ぼす影響を検討した.2分虚血により虚血耐性を誘導し,その48時間後に5分虚血を行う砂ネズミ一過性前脳虚血モデルを用いた.薬剤は,2分虚血24時間後にvehicle,PPF10mg/kg,PPF20mg/kgを腹腔内投与し,更にnon-selective adenosine receptor antagonistであるtheophyllineを同時投与した.又,PPF20mg/kgを5分単独虚血24時間前に投与して,その影響を検討した.vehicle群では,preconditioning ischemiaによる海馬CA1錘体細胞死への保護効果が認められ,PPF10mg/kgでも同様であった.しかし,PPF20mg/kg投与群ではこれら2群に対し有意にCA1錐体細胞障害が軽く,虚血耐性増強効果が確認された.更に,この増強効果はtheophyllineの同時投与によって消失した
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日本応用磁気学会学術講演概要集 = Digest of ... annual conference on magnetics in Japan 22 369-369 1998年9月1日
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Neuropathology : official journal the Japanese Society of Neuropathology 17(Suppl.) 279-279 1997年5月26日
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Neuropathology : official journal the Japanese Society of Neuropathology 17(Suppl.) 295-295 1997年5月26日
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JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM 15(2) 205-215 1995年3月Levels of mRNAs encoding the microtubule-associated proteins MAP2b and MAP2c as well as the 70-kDa stress protein [72-kDa heat shock protein (hsp72)] were evaluated in postischemic rat brain by in situ hybridization with oligonucleotide probes corresponding to the known rat sequences. Rats were subjected to 10-min cardiac arrest, produced by compression of major thoracic vessels, followed by resuscitation. The normally expressed MAP2b mRNA showed transient twofold elevations in all hippocampal neuron populations at 6-h recirculation, followed by a return to control levels by 24 h. MAP2b hybridization was progressively lost thereafter from the vulnerable CA1 and outer cortical layers, preceding both the fall in immunoreactive MAP2b and the eventual cell loss in these regions, The depletion of MAP2b mRNA coincided with an increase in the alternatively spliced MAP2c in vulnerable regions during 12-48 h of recirculation, precisely overlapping the late component of hsp72 expression that persisted in these cell populations. Previous studies have suggested that the initial induction of hsp72 provides an index of potential postischemic injury in neuron populations that may or may not be injured, while lasting hsp72 mRNA expression is associated with cell damage. In contrast, the present results demonstrate that MAP2c expression under these conditions occurs uniquely in neuron populations subject to injury. Available evidence suggests that MAP2c expression represents a plastic response in subpopulations of neurons that will survive in these regions, although it remains to be explicitly determined whether it may also be transiently expressed in dying cells. In any case, these observations demonstrate that reexpression of developmentally regulated MAP2c mRNA is a relatively late postischemic response in vulnerable cell populations, indicating that pathways regulating MAP2 splicing may be closely associated with mechanisms of neuron injury and/or recovery.
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BRAIN EDEMA VIII 51(186) 186-188 1990年
書籍等出版物
5所属学協会
5共同研究・競争的資金等の研究課題
25-
日本学術振興会 科学研究費助成事業 2023年4月 - 2026年3月
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日本学術振興会 科学研究費助成事業 2021年4月 - 2024年3月
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日本学術振興会 科学研究費助成事業 2020年4月 - 2023年3月
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日本学術振興会 科学研究費助成事業 2019年4月 - 2022年3月
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日本学術振興会 科学研究費助成事業 2016年4月 - 2020年3月