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51.
Probabilistic classification learning with corrective feedback is associated with in vivo striatal dopamine release in the ventral striatum,while learning without feedback is not 下载免费PDF全文
Yen Foung Tai Chia Shu Lin David Albert Lagnado David James Brooks Paola Piccini Marjan Jahanshahi 《Human brain mapping》2014,35(10):5106-5115
The basal ganglia (BG) mediate certain types of procedural learning, such as probabilistic classification learning on the ‘weather prediction task’ (WPT). Patients with Parkinson's disease (PD), who have BG dysfunction, are impaired at WPT‐learning, but it remains unclear what component of the WPT is important for learning to occur. We tested the hypothesis that learning through processing of corrective feedback is the essential component and is associated with release of striatal dopamine. We employed two WPT paradigms, either involving learning via processing of corrective feedback (FB) or in a paired associate manner (PA). To test the prediction that learning on the FB but not PA paradigm would be associated with dopamine release in the striatum, we used serial 11C‐raclopride (RAC) positron emission tomography (PET), to investigate striatal dopamine release during FB and PA WPT‐learning in healthy individuals. Two groups, FB, (n = 7) and PA (n = 8), underwent RAC PET twice, once while performing the WPT and once during a control task. Based on a region‐of‐interest approach, striatal RAC‐binding potentials reduced by 13–17% in the right ventral striatum when performing the FB compared to control task, indicating release of synaptic dopamine. In contrast, right ventral striatal RAC binding non‐significantly increased by 9% during the PA task. While differences between the FB and PA versions of the WPT in effort and decision‐making is also relevant, we conclude striatal dopamine is released during FB‐based WPT‐learning, implicating the striatum and its dopamine connections in mediating learning with FB. Hum Brain Mapp 35:5106–5115, 2014. © 2014 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc. 相似文献
52.
Inge Leunissen James P. Coxon Karen Caeyenberghs Karla Michiels Stefan Sunaert Stephan P. Swinnen 《Human brain mapping》2014,35(5):2459-2469
Suppressing and flexibly adapting actions are a critical part of our daily behavioral repertoire. Traumatic brain injury (TBI) patients show clear impairments in this type of action control; however, the underlying mechanisms are poorly understood. Here, we tested whether white matter integrity of cortico‐subcortical pathways could account for impairments in task switching, an important component of executive functioning. Twenty young adults with TBI and eighteen controls performed a switching task requiring attention to global versus local stimulus features. Diffusion weighted images were acquired and whole brain tract‐based spatial statistics (TBSS) were used to explore where white matter damage was associated with switching impairment. A crossing fiber model and probabilistic tractography further identified the specific fiber populations. Relative to controls, patients with a history of TBI had a higher switch cost and were less accurate. The TBI group showed a widespread decline in fractional anisotropy (FA) throughout the TBSS skeleton. FA in the superior corona radiata showed a negative relationship with switch cost. More specifically, this involved cortico‐subcortical loops with the (pre‐)supplementary motor area and superior frontal gyrus. These findings provide evidence for damage to frontal‐subcortical projections in TBI, which is associated with task switching impairments. Hum Brain Mapp 35:2459–2469, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
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Hildebrand ME Smith PL Bladen C Eduljee C Xie JY Chen L Fee-Maki M Doering CJ Mezeyova J Zhu Y Belardetti F Pajouhesh H Parker D Arneric SP Parmar M Porreca F Tringham E Zamponi GW Snutch TP 《Pain》2011,152(4):833-843
Voltage-gated ion channels are implicated in pain sensation and transmission signaling mechanisms within both peripheral nociceptors and the spinal cord. Genetic knockdown and knockout experiments have shown that specific channel isoforms, including NaV1.7 and NaV1.8 sodium channels and CaV3.2 T-type calcium channels, play distinct pronociceptive roles. We have rationally designed and synthesized a novel small organic compound (Z123212) that modulates both recombinant and native sodium and calcium channel currents by selectively stabilizing channels in their slow-inactivated state. Slow inactivation of voltage-gated channels can function as a brake during periods of neuronal hyperexcitability, and Z123212 was found to reduce the excitability of both peripheral nociceptors and lamina I/II spinal cord neurons in a state-dependent manner. In vivo experiments demonstrate that oral administration of Z123212 is efficacious in reversing thermal hyperalgesia and tactile allodynia in the rat spinal nerve ligation model of neuropathic pain and also produces acute antinociception in the hot-plate test. At therapeutically relevant concentrations, Z123212 did not cause significant motor or cardiovascular adverse effects. Taken together, the state-dependent inhibition of sodium and calcium channels in both the peripheral and central pain signaling pathways may provide a synergistic mechanism toward the development of a novel class of pain therapeutics. 相似文献
55.
Changgui Shi Sujun Qiu Scott M. Riester Vaskar Das Bingqian Zhu Atiyayein A. Wallace Andre J. van Wijnen Fackson Mwale James C. Iatridis Daisuke Sakai Gina Votta‐Velis Wen Yuan Hee‐Jeong Im 《Journal of orthopaedic research》2018,36(5):1305-1312
56.
Maria G Onesti Pasquale Fino Paolo Fioramonti Vittoria Amorosi Nicolò Scuderi 《International wound journal》2015,12(4):447-450
Malignant degeneration of wounds is rare and often misdiagnosed. Delay in diagnosis may result in a worse prognosis. The aim of this study is to determine the number of skin cancers associated with chronic skin ulcers in our facility over a period of 10 years. Between January 2002 and December 2012, a total of about 1000 patients had consulted with us for chronic wounds, especially of vascular, diabetic and traumatic origin and pressure ulcers. Thirteen skin cancers had been detected: seven squamous cell and five basal cell carcinomas and one melanoma. We highlight how important it is to be aware of the signs suggesting a malignant change and the importance of biopsy at regular intervals during the life cycle of any chronic wound. 相似文献
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58.
E. Martha Pérez Armendariz Monica Norcini Beatriz Hernández-Tellez Andrés Castell-Rodríguez Cristina Coronel-Cruz Raquel Guerrero Alquicira Alexandra Sideris Esperanza Recio-Pinto 《Acta histochemica》2018,120(3):168-178
Previous studies have shown that following peripheral nerve injury there was a downregulation of the gap junction protein connexin 36 (Cx36) in the spinal cord; however, it is not known whether Cx36 protein is expressed in the dorsal root ganglia (DRGs), nor if its levels are altered following peripheral nerve injuries. Here we address these aspects in the adult rat lumbar DRG. Cx36 mRNA was detected using qRT-PCR, and Cx36 protein was identified in DRG sections using immunohistochemistry (IHC) and immunofluorescence (IF). Double staining revealed that Cx36 co-localizes with both anti-β-III tubulin, a neuronal marker, and anti-glutamine synthetase, a satellite glial cell (SGC) marker. In neurons, Cx36 staining was mostly uniform in somata and fibers of all sizes and its intensity increased at the cell membranes. This labeling pattern was in contrast with Cx36 IF dots mainly found at junctional membranes in islet beta cells used as a control tissue. Co-staining with anti-Cx43 and anti-Cx36 showed that whereas mostly uniform staining of Cx36 was found throughout neurons and SGCs, Cx43 IF puncta were localized to SGCs. Cx36 mRNA was expressed in normal lumbar DRG, and it was significantly down-regulated in L4 DRG of rats that underwent sciatic nerve injury resulting in persistent hypersensitivity. Collectively, these findings demonstrated that neurons and SGCs express Cx36 protein in normal DRG, and suggested that perturbation of Cx36 levels may contribute to chronic neuropathic pain resulting from a peripheral nerve injury. 相似文献
59.
Serotonergic paraneurones in the female mouse urethral epithelium and their potential role in peripheral sensory information processing 下载免费PDF全文
60.
Clarification of the Innervation of the Bladder,External Urethral Sphincter and Clitoris: A Neuronal Tracing Study in Female Mongrel Hound Dogs 下载免费PDF全文
Mary F. Barbe Sandra M. Gomez‐Amaya Danielle M. Salvadeo Neil S. Lamarre Ekta Tiwari Shalonda Cook Connor P Glair Daniel H. Jang Rachel M. Ragheb Akaash Sheth Alan S. Braverman Michael R. Ruggieri 《Anatomical record (Hoboken, N.J. : 2007)》2018,301(8):1426-1441
Many studies examining the innervation of genitourinary structures focus on either afferent or efferent inputs, or on only one structure of the system. We aimed to clarify innervation of the bladder, external urethral sphincter (EUS) and clitoris. Retrograde dyes were injected into each end organ in female dogs. Spinal cord, mid‐bladder, and spinal, caudal mesenteric, sympathetic trunk and pelvic plexus ganglia were examined for retrograde dye‐labeled neurons. Neurons retrogradely labeled from the bladder were found primarily in L7‐S2 spinal ganglia, spinal cord lateral zona intermedia at S1‐S3 levels, caudal mesenteric ganglia, T11‐L2 and L6‐S2 sympathetic trunk ganglia, and pelvic plexus ganglia. The mid‐bladder wall contained many intramural ganglia neurons labeled anterogradely from the pelvic nerve, and intramural ganglia retrogradely labeled from dye labeling sites surrounding ureteral orifices. Neurons retrogradely labeled from the clitoris were found only in L7 and S1 spinal ganglia, L7‐S3 spinal cord lateral zona intermedia, and S1 sympathetic trunk ganglia, and caudal mesenteric ganglia. Neurons retrogradely labeled from the EUS were found in primarily at S1 and S2 spinal ganglia, spinal cord lamina IX at S1‐S3, caudal mesenteric ganglia, and S1‐S2 sympathetic trunk ganglia. Thus, direct inputs from the spinal cord to each end organ were identified, as well as multisynaptic circuits involving several ganglia, including intramural ganglia in the bladder wall. Knowledge of this complex circuitry of afferent and efferent inputs to genitourinary structures is necessary to understand and treat genitourinary dysfunction. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc. 相似文献