1,429 research outputs found
Author response image 1.
No full textNeurotransmitter is released at synapses by fusion of synaptic vesicles with the plasma membrane. To sustain synaptic transmission, compensatory retrieval of membranes and vesicular proteins is essential. We combined capacitance measurements and pH-imaging via pH-sensitive vesicular protein marker (anti-synaptotagmin2-cypHer5E), and compared the retrieval kinetics of membranes and vesicular proteins at the calyx of Held synapse. Membrane and Syt2 were retrieved with a similar time course when slow endocytosis was elicited. When fast endocytosis was elicited, Syt2 was still retrieved together with the membrane, but endocytosed organelle re-acidification was slowed down, which provides strong evidence for two distinct endocytotic pathways. Strikingly, CaM inhibitors or the inhibition of the Ca2+-calmodulin-Munc13-1 signaling pathway only impaired the uptake of Syt2 while leaving membrane retrieval intact, indicating different recycling mechanisms for membranes and vesicle proteins. Our data identify a novel mechanism of stimulus-and Ca2+-dependent regulation of coordinated endocytosis of synaptic membranes and vesicle proteins
Replacement-free electrodeless quartz crystal microbalance biosensor using nonspecific-adsorption of streptavidin on quartz
No full textHirotsugu Ogi, Ken Okamoto, Hironao Nagai, Yuji Fukunishi, and Masahiko Hirao. Replacement-free electrodeless quartz crystal microbalance biosensor using nonspecific-adsorption of streptavidin on quartz. Analytical Chemistry, 2009, 81(10), 4015-4020. ©2009 American Chemical Society. https://doi.org/10.1021/ac9004524.This paper proposes a replacement-free and surface-modification-free quartz crystal microbalance (QCM) biosensor. With the use of significant nonspecific adsorption of streptavidin on naked quartz surfaces, target analyte is detected through biotin-tagged receptors on streptavidin. The wireless-electrodeless QCM technique is developed with a 30 μm thick AT-cut quartz plate, whose fundamental resonance frequency is 55 MHz, and the naked quartz surfaces are used for the nonspecific adsorption of streptavidin. Once it is installed in the sensor cell, it can be used semipermanently; it never needs to be replaced. The equilibrium dissociation constant of streptavidin on quartz is determined to be 1.3 × 10⁻⁷M. The flow rate affected the number of the adsorbed streptavidin on quartz as well as the binding velocity
Presynaptic cAMP-PKA-mediated potentiation induces reconfiguration of synaptic vesicle pools and channel-vesicle coupling at hippocampal mossy fiber boutons
No full textIt is widely believed that information storage in neuronal circuits involves nanoscopic structural changes at synapses, resulting in the formation of synaptic engrams. However, direct evidence for this hypothesis is lacking. To test this conjecture, we combined chemical potentiation, functional analysis by paired pre-postsynaptic recordings, and structural analysis by electron microscopy (EM) and freeze-fracture replica labeling (FRL) at the rodent hippocampal mossy fiber synapse, a key synapse in the trisynaptic circuit of the hippocampus. Biophysical analysis of synaptic transmission revealed that forskolin-induced chemical potentiation increased the readily releasable vesicle pool size and vesicular release probability by 146% and 49%, respectively. Structural analysis of mossy fiber synapses by EM and FRL demonstrated an increase in the number of vesicles close to the plasma membrane and the number of clusters of the priming protein Munc13-1, indicating an increase in the number of both docked and primed vesicles. Furthermore, FRL analysis revealed a significant reduction of the distance between Munc13-1 and Ca V 2.1 Ca 2+ channels, suggesting reconfiguration of the channel-vesicle coupling nanotopography. Our results indicate that presynaptic plasticity is associated with structural reorganization of active zones. We propose that changes in potential nanoscopic organization at synaptic vesicle release sites may be correlates of learning and memory at a plastic central synapse.European Research Council http://dx.doi.org/10.13039/501100000781Austrian Science Fund http://dx.doi.org/10.13039/501100002428Austrian Science Fund http://dx.doi.org/10.13039/501100002428Austrian Science Fund http://dx.doi.org/10.13039/501100002428Austrian Science Fund http://dx.doi.org/10.13039/50110000242
The Eagles, 1946 Seabrook Athletic Union
No full textThe Eagles were the nucleus of the club later formed and known as The Blue Devils. They were the 146 Seabrook Athletic Union "B" League Slftball Champions. Pictured Kneeline: Tomio "Chin" Kuramoto, Kaname "Smokey" Okamoto, Naru Shimoda, Minoru "Mimpo" Hirata, Jiro Mukai, Tak Kawashiri, Yuji "Gabby" Hirata Standing: Ray Ono, Shiro Kubota, Mutsuo Kuramoto, Ken Ouye, Ted Muragishi, david Nakauchi, Isamu
Estudo teorico das relações estrutura - atividade biologica sobre a inibição por cumarinas da mutagenese induzida pela 2-amino-3-metilimizado [4,5 - f] quinolina em Salmonella typhimurium TA98
No full textOrientador: Yuji TakahataDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de QuimicaMestrad
A case of ectopic ureterocele in a male adult found during examination of a traumatic injury
No full text26歳男.サッカーで左背部打撲後, 腹部痛が出現した.CTで後腹膜腔に巨大な嚢胞性腫瘤とその内部に尿管と考えられる索状物を認めた.膀胱鏡検査では左尿道管～膀胱頸部の膨隆と前立腺部尿道の膨隆下端に尿管口を認めた.RPを施行したところ, 左上半腎所属尿管による膀胱への圧排像を認め, 左上半腎所属尿管は外側に圧排偏位し, 水腎症を呈していた.カテーテルを留置し保存的に経過観察した.ドレナージにより腎機能は改善した.その後, 左上半腎所属尿管に対して経尿道的異所性尿管瘤切開術を施行した.術後1ヵ月, VURを認めるものの左水腎症は改善し, 術後7ヵ月の現在, 排尿障害, 尿路感染は認めていないWe report a case of ectopic ureterocele in a male adult found during examination of a traumatic injury. A 26-year-old man sustained a blow to his left back during a football game and was admitted to the hospital with a complaint of abdominal pain. The computed tomographic scan showed a huge cystic mass in the retroperitoneum. A cystoscope revealed a large bulge from the left ureteral orifice to the bladder neck and another ureteral orifice distal to the bulge. Retrograde pyelography revealed an ectopic ureterocele showing a complete duplication, a lateral deviation of the left ureter and a bladder deviation to the right. An ectopic ureteral orifice was opening in the posterior urethra. An ureteral catheter inserted into this orifice revealed a dilated left ureter from the upper half of the kidney. Because the function of left upper of kidney was maintained, a transurethral incision was performed. Vesicoureteral reflux remained, but the postoperative course was uneventful. We discuss 11 cases of ectopic ureterocele in male adults including this case
N=2 supersymmetric dynamics for pedestrians
No full textUnderstanding the dynamics of gauge theories is crucial, given the fact that all known interactions are based on the principle of local gauge symmetry. Beyond the perturbative regime, however, this is a notoriously difficult problem. Requiring invariance under supersymmetry turns out to be a suitable tool for analyzing supersymmetric gauge theories over a larger region of the space of parameters. Supersymmetric quantum field theories in four dimensions with extended N=2 supersymmetry are further constrained and have therefore been a fertile field of research in theoretical physics for quite some time. Moreover, there are far-reaching mathematical ramifications that have led to a successful dialogue with differential and algebraic geometry. These lecture notes aim to introduce students of modern theoretical physics to the fascinating developments in the understanding of N=2 supersymmetric gauge theories in a coherent fashion. Starting with a gentle introduction to electric-magnetic duality, the author guides readers through the key milestones in the field, which include the work of Seiberg and Witten, Nekrasov, Gaiotto and many others. As an advanced graduate level text, it assumes that readers have a working knowledge of supersymmetry including the formalism of superfields, as well as of quantum field theory techniques such as regularization, renormalization and anomalies. After his graduation from the University of Tokyo, Yuji Tachikawa worked at the Institute for Advanced Study, Princeton and the Kavli Institute for Physics and Mathematics of the Universe. Presently at the Department of Physics, University of Tokyo, Tachikawa is the author of several important papers in supersymmetric quantum field theories and string theory
Seven connection patterns between the author research areas.
No full textSeven connection patterns between the author research areas.</p
液相焼結現象の初期過程の研究
No full text京都大学0048新制・課程博士理学博士理博第46号新制||理||19(附属図書館)256京都大学大学院理学研究科化学専攻(主査)教授 可知 祐次, 教授 高木 秀夫, 教授 小寺 熊三郎学位規則第5条第1項該当Kyoto UniversityDA
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