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71.
Disconnection of a basal ganglia circuit in juvenile songbirds attenuates the spectral differentiation of song syllables 下载免费PDF全文
Frank Johnson 《Developmental neurobiology》2014,74(6):574-590
Similar to language acquisition by human infants, juvenile male zebra finches (Taeniopygia guttata) imitate an adult (tutor) song by transitioning from repetitive production of one or two undifferentiated protosyllables to the sequential production of a larger and spectrally heterogeneous set of syllables. The primary motor region that controls learned song is driven by a confluence of input from two premotor pathways: a posterior pathway that encodes the adult song syllables and an anterior pathway that includes a basal ganglia (BG)‐thalamo‐cortical circuit. Similar to mammalian motor‐learning systems, the songbird BG circuit is thought to be necessary for shaping juvenile vocal behaviour (undifferentiated protosyllables) toward specific targets (the tutor's song syllables). Here, we tested the hypothesis that anterior pathway activity contributes to the process of protosyllable differentiation. Bilateral ablation of lateral magnocellular nucleus of the anterior nidopallium (LMAN) was used to disconnect BG circuitry at ages before protosyllable production and differentiation. Comparison to surgical controls revealed that protosyllables fail to differentiate in birds that received juvenile LMAN ablation—the adult songs of birds with >80% bilateral LMAN ablation consisted of only one or two syllables produced with the repetitive form and spectral structure that characterizes undifferentiated protosyllables in normal juveniles. Our findings support a role for BG circuitry in shaping juvenile vocal behaviour toward the acoustic structure of the tutor song and suggest that posterior pathway function remains in an immature “default” state when developmental interaction with the anterior pathway is reduced or eliminated. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 74: 574–590, 2014 相似文献
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The activities of several enzymes involved in the metabolism of aspartate and glutamate were measured in striatal (nucleus caudatus and putamen) homogenates 2-3, 6-7, and 35-40 days following frontoparietal and frontal cortical ablation. The activity of glutamine synthetase (GS) was substantially increased (46-48%) on the operated side 6-7 days following the lesion whereas smaller changes were observed at 2-3 and 35-40 days after lesion. In contrast, decreased levels of glutaminase and malate dehydrogenase (MDH) were observed by 6-7 days while no significant change was found at either 2-3 or 35-40 after the lesion. The activities of glutamate dehydrogenase (GDH) and glutamate decarboxylase (GAD) were elevated after 35-40 days whereas no changes in the levels of either GDH or aspartate aminotransferase (ASAT) were found at 2-3 or 6-7 days after the fronto-parietal decortication. When only the frontal cortex was removed quantitatively similar changes were observed in striatal GS and glutaminase activity. The content of glutamate and glutamine in the denervated striatum followed qualitatively the changes in glutaminase and GS. The results indicate that the degeneration of cortico-striatal terminals causes a profound glial reaction in the striatum, and both glutaminase and MDH are present in relatively high concentrations in the corticostriatal terminals. 相似文献
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Ryuta Mikawa Yohei Suzuki Hario Baskoro Kazuki Kanayama Kazushi Sugimoto Tadashi Sato Masataka Sugimoto 《Aging cell》2018,17(5)
Senescent cells accumulate in tissues during aging and are considered to underlie several aging‐associated phenotypes and diseases. We recently reported that the elimination of p19ARF‐expressing senescent cells from lung tissue restored tissue function and gene expression in middle‐aged (12‐month‐old) mice. The aging of lung tissue increases the risk of pulmonary diseases such as emphysema, and cellular senescence is accelerated in emphysema patients. However, there is currently no direct evidence to show that cellular senescence promotes the pathology of emphysema, and the involvement of senescence in the development of this disease has yet to be clarified. We herein demonstrated that p19ARF facilitated the development of pulmonary emphysema in mice. The elimination of p19ARF‐expressing cells prevented lung tissue from elastase‐induced lung dysfunction. These effects appeared to depend on reduced pulmonary inflammation, which is enhanced after elastase stimulation. Furthermore, the administration of a senolytic drug that selectively kills senescent cells attenuated emphysema‐associated pathologies. These results strongly suggest the potential of senescent cells as therapeutic/preventive targets for pulmonary emphysema. 相似文献
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Sana Ouali Manel Ben Halima Selim Boudiche Anissa Gharbi Khedher Nadim Kaouthar Hakim Fatma Ouarda Mohamed Sami Mourali 《Indian pacing and electrophysiology journal》2018,18(2):76-79
A 04-year-old boy was referred to our institution with severe, progressive heart failure of 4-months duration associated with a persistent wide QRS tachycardia with left bundle branch block and severe left ventricular dysfunction. Because of incessant wide QRS tachycardia refractory to antiarrhythmic drugs, he was referred for electrophysiological study. The ECG was suggestive of VT arising from the right ventricle near the His area. Electrophysiological study revealed that origin of tachycardia was septum of the right ventricle, near His bundle, however the procedure was not successful and an inadvertent complete atrioventricular conduction block occurred. The same ventricular tachycardia recurred. A second procedure was performed with a retrograd aortic approach to map the left side of the interventricular septum. The earliest endocardial site for ablation was localized in the anterobasal region of left ventricle near His bundle. In this location, one radiofrequency pulse interrupted VT and rendered it not inducible. The echocardiographic evaluation showed partial reversal of left ventricular function in the first 3 months. The diagnosis was idiopathic parahisian left ventricular tachycardia leading to a tachycardia mediated cardiomyopathy, an extremely rare clinical picture in children. 相似文献
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Antonio Scarà Luigi Sciarra Ermenegildo De Ruvo Alessio Borrelli Domenico Grieco Zefferino Palamà Paolo Golia Lucia De Luca Marco Rebecchi Leonardo Calò 《Indian pacing and electrophysiology journal》2018,18(2):61-67
Background
The Amigo® Remote Catheter System is a relatively new robotic system for catheter navigation. This study compared feasibility and safety using Amigo (RCM) versus manual catheter manipulation (MCM) to treat paroxysmal atrial fibrillation (PAF). Contact force (CF) and force-time integral (FTI) values obtained during pulmonary vein isolation (PVI) ablation were compared.Methods
Forty patients were randomly selected for either RCM (20) or MCM (20). All were studied with the Thermocool® SmartTouch® force-sensing catheter (STc). Contact Force (CF), Force Time Integral (FTI) and procedure-related data, were measured/stored in the CARTO®3.Results
All cases achieved complete PVI without major complications. Mean CF was significantly higher in the RCM group (13.3 ± 7.7 g in RCM vs. 12.04 ± 7.42 g in MCM p < 0.001), as was overall mean FTI (425.6 gs ± 199.6 gs with RCM and 407.5 gs ± 288.0 gs in MCM (p = 0.007) and was more likely to fall into the optimal FTI range (400-1000) using RCM (66.1% versus 49.1%, p < 0.001). FTI was significantly more likely to fall within the optimal range in each PV, as was CF within its optimal range in the right PVs, but trended higher in the left PVs. Freedom from atrial tachyarrhythmia was 90.0% for the RCM and 70.0% for the MCM group (p = 0,12) at 540 days follow-up.Conclusions
This pilot study suggests that use of the Amigo RCM system, with STc catheter, seems to be safe and effective for PVI ablation in paroxysmal AF patients. A not statistically significant favorable trend was observed for RCM in term of AF-free survival. 相似文献80.
Sen Matsumoto Yasuharu Matsunaga-Lee Nobutaka Masunaga Yuzuru Takano 《Indian pacing and electrophysiology journal》2018,18(4):155-158
A 69-year-old woman with palpitations was referred to our hospital for a second session of atrial fibrillation (AF) catheter ablation. She had a history of AF ablation including pulmonary vein (PV) isolation and persistent left superior vena cava (PLSVC) isolation. Electrophysiologic studies showed the veno-atrial connections that had recovered. After PV isolation was performed, AF was induced by atrial premature contraction (APC) from the PLSVC, and AF storm occurred. During PLSVC isolation, AF was not induced by APC from the PLSVC. PLSVC isolation continued during sinus rhythm. The elimination of the PLSVC potential was difficult to confirm because of the far-field potential of the left ventricle. Then, we performed right ventricular pacing. The remaining PLSVC potential was identified. After that, the PLSVC isolation was successful during right ventricular pacing. Complications were not observed. The patient had no recurrence of AF thereafter. 相似文献