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1.
Cell Rep ; 43(5): 114196, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38717902

RESUMO

Memory recall and guidance are essential for motor skill acquisition. Like humans learning to speak, male zebra finches learn to sing by first memorizing and then matching their vocalization to the tutor's song (TS) during specific developmental periods. Yet, the neuroanatomical substrate supporting auditory-memory-guided sensorimotor learning has remained elusive. Here, using a whole-brain connectome analysis with activity-dependent viral expression, we identified a transient projection into the motor region, HVC, from neuronal ensembles responding to TS in the auditory forebrain, the caudomedial nidopallium (NCM), in juveniles. Virally induced cell death of the juvenile, but not adult, TS-responsive NCM neurons impaired song learning. Moreover, isolation, which delays closure of the sensory, but not the motor, learning period, did not affect the decrease of projections into the HVC from the NCM TS-responsive neurons after the song learning period. Taken together, our results suggest that dynamic axonal pruning may regulate timely auditory-memory-guided vocal learning during development.


Assuntos
Tentilhões , Aprendizagem , Vocalização Animal , Animais , Vocalização Animal/fisiologia , Tentilhões/fisiologia , Aprendizagem/fisiologia , Masculino , Neurônios/fisiologia , Conectoma
2.
JA Clin Rep ; 9(1): 17, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37022659

RESUMO

BACKGROUND: Although most patients of eosinophilic granulomatosis with polyangiitis (EGPA) experience a reduction in pain within several weeks to months of the initiation of immunotherapies, some suffer from residual neuropathic symptoms for a long time. CASE PRESENTATION: A 28-year-old woman diagnosed with EGPA visited. She had been treated with steroid pulse therapy, intravenous immunoglobulin, and mepolizumab (antiinterleukin-5 agent). Her symptoms other than peripheral neuropathy improved, but posterior lower thigh pain and weakness of the lower legs worsened. At the initial visit, she used crutches and complained of numb pain in both posterior lower thighs, especially the left one. She also presented with left foot drop and reported a decreased tactile sensation on the lateral sides of both lower thighs. We performed spinal cord stimulation (SCS) at the L1 level on both sides. Her pain remarkably decreased, her tactile sensation improved, her muscle strength increased, and she was able to walk without crutches. CONCLUSIONS: We herein report the first case of lower extremity pain being successfully treated with SCS in an EGPA patient who did not respond well to drug therapy. Because the cause of pain in EGPA is neuropathy induced by vasculitis, there is ample ability for SCS to improve this pain. When pain is neuropathic, whatever the cause, SCS may be worth trying, even for pain from disorders other than EGPA.

3.
Cereb Cortex ; 33(7): 3401-3420, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35849820

RESUMO

Sensory neurons parse millisecond-variant sound streams like birdsong and speech with exquisite precision. The auditory pallial cortex of vocal learners like humans and songbirds contains an unconventional neuromodulatory system: neuronal expression of the estrogen synthesis enzyme aromatase. Local forebrain neuroestrogens fluctuate when songbirds hear a song, and subsequently modulate bursting, gain, and temporal coding properties of auditory neurons. However, the way neuroestrogens shape intrinsic and synaptic properties of sensory neurons remains unknown. Here, using a combination of whole-cell patch clamp electrophysiology and calcium imaging, we investigate estrogenic neuromodulation of auditory neurons in a region resembling mammalian auditory association cortex. We found that estradiol rapidly enhances the temporal precision of neuronal firing via a membrane-bound G-protein coupled receptor and that estradiol rapidly suppresses inhibitory synaptic currents while sparing excitation. Notably, the rapid suppression of intrinsic excitability by estradiol was predicted by membrane input resistance and was observed in both males and females. These findings were corroborated by analysis of in vivo electrophysiology recordings, in which local estrogen synthesis blockade caused acute disruption of the temporal correlation of song-evoked firing patterns. Therefore, on a modulatory timescale, neuroestrogens alter intrinsic cellular properties and inhibitory neurotransmitter release to regulate the temporal precision of higher-order sensory neurons.


Assuntos
Córtex Auditivo , Tentilhões , Humanos , Masculino , Animais , Feminino , Estrogênios/farmacologia , Tentilhões/metabolismo , Vocalização Animal/fisiologia , Estradiol , Córtex Auditivo/fisiologia , Neurônios/fisiologia , Mamíferos/metabolismo
4.
J Anesth ; 36(6): 671-687, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36069935

RESUMO

Smoking is closely associated with the development of various cancers and tobacco-related illnesses such as cardiovascular and respiratory disorders. However, data are scarce on the relationship between smoking and both acute and chronic pain. In addition to nicotine, tobacco smoke contains more than 4000 different compounds. Although nicotine is not the sole cause of smoking-induced diseases, it plays a critical role in pain-related pathophysiology. Despite the acute analgesic effects of nicotine, long-term exposure leads to tolerance and increased pain sensitivity due to nicotinic acetylcholine receptor desensitization and neuronal plastic changes. The purpose of smoking cessation interventions in smoking patients with pain is primarily not only to reduce their pain and associated limitations in activities of daily living, but also to improve the outcomes of underlying pain-causing conditions and reduce the risks of tobacco-related disorders. This statement aims to summarize the available evidence on the impact of smoking on pain and to inform medical professionals of the significance of smoking cessation in patients with pain.


Assuntos
Dor Crônica , Abandono do Hábito de Fumar , Humanos , Nicotina/farmacologia , Atividades Cotidianas , Fumar/efeitos adversos , Fumar/terapia , Dor Crônica/terapia
5.
Nat Commun ; 13(1): 4442, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35973980

RESUMO

Social interactions are essential when learning to communicate. In human speech and bird song, infants must acquire accurate vocalization patterns and learn to associate them with live tutors and not mimetic sources. However, the neural mechanism of social reality during vocal learning remains unknown. Here, we characterize a neural circuit for social authentication in support of accurate song learning in the zebra finch. We recorded neural activity in the attention/arousal state control center, the locus coeruleus (LC), of juvenile birds during song learning from a live adult tutor. LC activity increased with real, not artificial, social information during learning that enhanced the precision and robustness of the learned song. During live social song learning, LC activity regulated long-term song-selective neural responsiveness in an auditory memory region, the caudomedial nidopallium (NCM). In accord, optogenetic inhibition of LC presynaptic signaling in the NCM reduced NCM neuronal responsiveness to live tutor singing and impaired song learning. These results demonstrate that the LC-NCM neural circuit integrates sensory evidence of real social interactions, distinct from song acoustic features, to authenticate song learning. The findings suggest a general mechanism for validating social information in brain development.


Assuntos
Tentilhões , Animais , Tentilhões/fisiologia , Humanos , Lactente , Neurônios/fisiologia , Fala , Vocalização Animal/fisiologia
6.
Curr Biol ; 31(13): 2831-2843.e6, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-33989528

RESUMO

In vertebrates, advanced cognitive abilities are typically associated with the telencephalic pallium. In mammals, the pallium is a layered mixture of excitatory and inhibitory neuronal populations with distinct molecular, physiological, and network phenotypes. This cortical architecture is proposed to support efficient, high-level information processing. Comparative perspectives across vertebrates provide a lens to understand the common features of pallium that are important for advanced cognition. Studies in songbirds have established strikingly parallel features of neuronal types between mammalian and avian pallium. However, lack of genetic access to defined pallial cell types in non-mammalian vertebrates has hindered progress in resolving connections between molecular and physiological phenotypes. A definitive mapping of the physiology of pallial cells onto their molecular identities in birds is critical for understanding how synaptic and computational properties depend on underlying molecular phenotypes. Using viral tools to target excitatory versus inhibitory neurons in the zebra finch auditory association pallium (calmodulin-dependent kinase alpha [CaMKIIα] and glutamate decarboxylase 1 [GAD1] promoters, respectively), we systematically tested predictions derived from mammalian pallium. We identified two genetically distinct neuronal populations that exhibit profound physiological and computational similarities with mammalian excitatory and inhibitory pallial cells, definitively aligning putative cell types in avian caudal nidopallium with these molecular identities. Specifically, genetically identified CaMKIIα and GAD1 cell types in avian auditory association pallium exhibit distinct intrinsic physiological parameters, distinct auditory coding principles, and inhibitory-dependent pallial synchrony, gamma oscillations, and local suppression. The retention, or convergence, of these molecular and physiological features in both birds and mammals clarifies the characteristics of pallial circuits for advanced cognitive abilities.


Assuntos
Aves Canoras , Telencéfalo , Animais , Mamíferos/genética , Neurônios , Aves Canoras/genética , Vertebrados
7.
Front Neural Circuits ; 14: 570174, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132855

RESUMO

Songbirds learn to sing much as humans learn to speak. In zebra finches, one of the premier songbird models, males learn to sing for later courtship through a multistep learning process during the developmental period. They first listen to and memorize the song of a tutor (normally their father) during the sensory learning period. Then, in the subsequent sensory-motor learning phase (with large overlap), they match their vocalizations to the memorized tutor song via auditory feedback and develop their own unique songs, which they maintain throughout their lives. Previous studies have suggested that memories of tutor songs are shaped in the caudomedial nidopallium (NCM) of the brain, which is analogous to the mammalian higher auditory cortex. Isolation during development, which extends the sensory learning period in males, alters song preference in adult females, and NCM inactivation decreases song preference. However, the development of neurophysiological properties of neurons in this area and the effect of isolation on these neurons have not yet been explained. Here, we performed whole-cell patch-clamp recording on NCM neurons from juvenile zebra finches during the sensory learning period, 20, 40, or 60 days post-hatching (DPH) and examined their neurophysiological properties. In contrast to previous reports in adult NCM neurons, the majority of NCM neurons of juvenile zebra finches showed spontaneous firing with or without burst firing patterns, and the percentage of neurons that fired increased in the middle of the sensory learning period (40 DPH) and then decreased at the end (60 DPH) in both males and females. We further found that auditory isolation from tutor songs alters developmental changes in the proportions of firing neurons both in males and females, and also changes those of burst neurons differently between males that sing and females that do not. Taken together, these findings suggest that NCM neurons develop their neurophysiological properties depending on auditory experiences during the sensory song learning period, which underlies memory formation for song learning in males and song discrimination in females.


Assuntos
Potenciais de Ação/fisiologia , Córtex Auditivo/fisiopatologia , Período Crítico Psicológico , Tentilhões , Aprendizagem/fisiologia , Neurônios/fisiologia , Privação Paterna , Vocalização Animal/fisiologia , Animais , Córtex Auditivo/fisiologia , Feminino , Masculino , Preferência de Acasalamento Animal , Técnicas de Patch-Clamp
8.
Brain Res ; 1714: 52-64, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30790559

RESUMO

We previously reported that mRNA encoding secreted phosphoprotein 1 (SPP1), also known as osteopontin, is preferentially expressed in large neurons in layer V of the macaque motor cortex, most of which are presumed to be corticospinal tract neurons. As a first step to elucidating the cellular function of SPP1 in macaque neurons, we examined the localization of SPP1 in the primary motor cortex (M1) of the macaque by using immunohistochemistry. SPP1 immunoreactivity was found to be localized in the cell bodies of neurons, but not outside the cells, indicating that SPP1 was not secreted from these neurons. The results of electron microscope analysis and double-labeling analysis with marker proteins suggested that SPP1 was localized in the mitochondria of neurons. The distributions of SPP1 in the neurons corresponded to those of integrin αV, a putative receptor for SPP1. The distribution of SPP1 was also investigated in macaques whose M1 had been lesioned. We found that SPP1 was secreted by proliferated microglia in the lesioned area. Double-labeling analysis indicated that SPP1 immunoreactivity in the microglia was colocalized with CD44, another putative receptor for SPP1. Success rates in the small-object-retrieval task were positively correlated with SPP1 immunoreactivity in the neurons in the perilesional area. SPP1 has multiple roles in the macaque motor cortex, and it may be a key protein during recovery of hand movement after brain damage.


Assuntos
Córtex Motor/metabolismo , Neurônios/metabolismo , Osteopontina/metabolismo , Animais , Feminino , Receptores de Hialuronatos/imunologia , Hibridização In Situ/métodos , Macaca mulatta , Masculino , Microglia/metabolismo , Córtex Motor/patologia , Osteopontina/genética , Osteopontina/fisiologia , Tratos Piramidais/metabolismo , RNA Mensageiro/metabolismo
9.
Behav Processes ; 163: 32-36, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29656094

RESUMO

Behavioral states of animals, such as observing the behavior of a conspecific, modify signal perception and/or sensations that influence state-dependent higher cognitive behavior, such as learning. Recent studies have shown that neuronal responsiveness to sensory signals is modified when animals are engaged in social interactions with others or in locomotor activities. However, how these changes produce state-dependent differences in higher cognitive function is still largely unknown. Zebra finches, which have served as the premier songbird model, learn to sing from early auditory experiences with tutors. They also learn from playback of recorded songs however, learning can be greatly improved when song models are provided through social communication with tutors (Eales, 1989; Chen et al., 2016). Recently we found a subset of neurons in the higher-level auditory cortex of juvenile zebra finches that exhibit highly selective auditory responses to the tutor song after song learning, suggesting an auditory memory trace of the tutor song (Yanagihara and Yazaki-Sugiyama, 2016). Here we show that auditory responses of these selective neurons became greater when juveniles were paired with their tutors, while responses of non-selective neurons did not change. These results suggest that social interaction modulates cortical activity and might function in state-dependent song learning.


Assuntos
Córtex Auditivo/fisiologia , Tentilhões/fisiologia , Relações Interpessoais , Aprendizagem/fisiologia , Neurônios/fisiologia , Vocalização Animal/fisiologia , Estimulação Acústica , Animais , Percepção Auditiva/fisiologia , Masculino
10.
Neurosci Res ; 140: 53-58, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30399390

RESUMO

Neuronal circuits are intensively shaped depending on experiences received during developmental critical periods. How neuronal circuits are sculpted can even affect the later development of higher cognitive functions, such as vocal communication skills. Here, we propose songbirds that learn to sing from early auditory experiences as a model for understanding the neuronal mechanisms underlying the development of multistep vocal learning. By applying the principal concepts of neuronal mechanisms for regulating the timing of critical periods, which have been well investigated by using experience-dependent mammalian cortical plasticity, we review our current understanding of the underlying neuronal mechanism of the song-learning critical period.


Assuntos
Vias Auditivas/fisiologia , Tentilhões/fisiologia , Aprendizagem/fisiologia , Neurônios/fisiologia , Vocalização Animal/fisiologia , Estimulação Acústica , Animais , Percepção Auditiva/fisiologia , Condicionamento Clássico , Modelos Neurológicos , Plasticidade Neuronal/fisiologia
11.
J Anesth ; 32(3): 434-438, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29523994

RESUMO

We performed a multicenter observational study to assess the prevalence and risk factors of persistent pain after lung cancer surgery and total knee arthroplasty (TKA) in the Japanese population. After receiving Ethics Committee approval, a retrospective chart review was performed for patients who underwent surgery at seven university hospitals in Japan in 2013. A total of 511 patients who underwent lung cancer surgery and 298 patients who underwent TKA were included. The prevalence of chronic postsurgical pain (CPSP) at 3 and 6 months was 18 and 12% after lung surgery and 49 and 33% after TKA, respectively. The prevalence of analgesic use at 3 and 6 months was 16 and 9% after lung surgery and 34 and 22% after TKA, respectively. In both groups, preoperative analgesic use was associated with CPSP. Anesthetic methods or techniques during both types of surgery did not significantly affect the prevalence of CPSP. This is the first study in which the prevalence of CPSP after lung surgery and TKA in Japanese population was extensively evaluated in a multicenter trial. Further prospective studies are needed to confirm the prevalence of CPSP in the Japanese population and to identify risk factors and prevention methods.


Assuntos
Artroplastia do Joelho/métodos , Dor Crônica/epidemiologia , Dor Pós-Operatória/epidemiologia , Toracotomia/métodos , Idoso , Idoso de 80 Anos ou mais , Analgésicos/administração & dosagem , Analgésicos Opioides/administração & dosagem , Anestesia/efeitos adversos , Anestesia/métodos , Artroplastia do Joelho/efeitos adversos , Dor Crônica/etiologia , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pregabalina/administração & dosagem , Prevalência , Estudos Retrospectivos , Fatores de Risco
12.
J Anesth ; 31(5): 686-691, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28638973

RESUMO

BACKGROUND: Acute kidney injury (AKI) has been found to be associated with short- and long-term mortality and morbidity in various clinical settings. However, it is unknown whether AKI after endovascular repair of abdominal aortic aneurysms (EVAR) is associated with postoperative mortality. METHODS: This observational study analyzed patients who underwent EVAR. The primary outcome was all-cause mortality. The outcomes of patients with and without postoperative AKI were compared using the Kaplan-Meier method and log-rank test. Factors with P < 0.05 on the univariate analysis were entered into the multivariate Cox regression model. Predictors of AKI were also determined using Cox univariate and multivariate analysis. The identified predictors of AKI were excluded from multivariate analysis for all-cause mortality because these factors could intermediate outcome. RESULTS: There were 490 eligible patients. After a follow-up of 28.3 (16.8) months [mean (standard deviation)], 62 patients (12.7%) died. AKI occurred in 59 patients (12.0%). AKI was found by the log-rank test to be associated with a significant increase of all-cause mortality (P < 0.001). Preoperative estimated glomerular filtration rate, preoperative peripheral vascular disease, and emergency surgery were found to be independent predictors of AKI and these variables were excluded from the main analysis. Multivariate analysis showed AKI [hazard ratio (HR) = 1.19, 95% confidence interval (CI) 1.01-3.60, P = 0.045] and transfusion (HR = 1.05, 95% CI 1.01-1.09, P = 0.011) were independent predictors of mortality. CONCLUSIONS: In the present study, AKI and transfusion were associated with significant increases in all-cause mortality after EVAR.


Assuntos
Injúria Renal Aguda/epidemiologia , Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares/métodos , Injúria Renal Aguda/etiologia , Idoso , Idoso de 80 Anos ou mais , Procedimentos Endovasculares/efeitos adversos , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Análise Multivariada , Estudos Retrospectivos , Resultado do Tratamento
13.
Science ; 354(6317): 1282-1287, 2016 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-27940872

RESUMO

Juvenile songbirds learn vocal communication from adult tutors of the same species but not from adults of other species. How species-specific learning emerges from the basic features of song prosody remains unknown. In the zebra finch auditory cortex, we discovered a class of neurons that register the silent temporal gaps between song syllables and are distinct from neurons encoding syllable morphology. Behavioral learning and neuronal coding of temporal gap structure resisted song tutoring from other species: Zebra finches fostered by Bengalese finch parents learned Bengalese finch song morphology transposed onto zebra finch temporal gaps. During the vocal learning period, temporal gap neurons fired selectively to zebra finch song. The innate temporal coding of intersyllable silent gaps suggests a neuronal barcode for conspecific vocal learning and social communication in acoustically diverse environments.


Assuntos
Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Tentilhões/fisiologia , Vocalização Animal/fisiologia , Animais , Córtex Auditivo/citologia , Aprendizagem/fisiologia , Masculino , Neurônios/fisiologia , Especificidade da Espécie
14.
Nat Commun ; 7: 11946, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27327620

RESUMO

As in human speech acquisition, songbird vocal learning depends on early auditory experience. During development, juvenile songbirds listen to and form auditory memories of adult tutor songs, which they use to shape their own vocalizations in later sensorimotor learning. The higher-level auditory cortex, called the caudomedial nidopallium (NCM), is a potential storage site for tutor song memory, but no direct electrophysiological evidence of tutor song memory has been found. Here, we identify the neuronal substrate for tutor song memory by recording single-neuron activity in the NCM of behaving juvenile zebra finches. After tutor song experience, a small subset of NCM neurons exhibit highly selective auditory responses to the tutor song. Moreover, blockade of GABAergic inhibition, and sleep decrease their selectivity. Taken together, these results suggest that experience-dependent recruitment of GABA-mediated inhibition shapes auditory cortical circuits, leading to sparse representation of tutor song memory in auditory cortical neurons.


Assuntos
Potenciais de Ação/fisiologia , Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Aprendizagem/fisiologia , Células Receptoras Sensoriais/metabolismo , Vocalização Animal/fisiologia , Estimulação Acústica , Potenciais de Ação/efeitos dos fármacos , Animais , Córtex Auditivo/citologia , Córtex Auditivo/efeitos dos fármacos , Cognição/fisiologia , Feminino , Tentilhões , Antagonistas GABAérgicos/farmacologia , Masculino , Inibição Neural/efeitos dos fármacos , Inibição Neural/fisiologia , Piridazinas/farmacologia , Receptores de GABA-A/metabolismo , Células Receptoras Sensoriais/citologia , Células Receptoras Sensoriais/efeitos dos fármacos , Análise de Célula Única , Sono/fisiologia , Ácido gama-Aminobutírico/metabolismo
15.
J Cardiothorac Vasc Anesth ; 29(4): 937-41, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25836954

RESUMO

OBJECTIVE: Postoperative respiratory complications are serious and frequently observed among patients who undergo thoracoabdominal aortic aneurysm (TAAA) repair. Paravertebral block (PVB) can provide effective analgesia for relief of postoperative thoracotomy pain and may reduce respiratory complications. However, the impact of PVB on postoperative pain and respiratory function in patients who undergo TAAA repair requiring intraoperative high-dose heparin administration is unknown. This study examined the efficacy of PVB on postoperative pain and respiratory function after TAAA repairs. DESIGN: Retrospective, observational cohort study. SETTING: Single center in Japan. PARTICIPANTS: Fifty-eight consecutive patients who underwent TAAA repair from March 2013 to October 2014. INTERVENTIONS: Application of thoracic PVB. MEASUREMENT AND MAIN RESULTS: A total of 56 patients were analyzed. Two patients were excluded because 1 patient was dead within 24 hours after surgery and 1 patient was 9 years old. Patients with PVB were defined as group P (n = 17), and patients without PVB as group C (n = 39). There was no significant difference in baseline characteristics between the 2 groups. Both postoperative pain at rest and postoperative pain while coughing were assessed using a numeric rating scale (NRS); the incidence of reintubation and noninvasive positive-pressure ventilation (NPPV) also were compared between the 2 groups. The NRS score of postoperative pain at rest was significantly lower in group P (group P: Median 2, interquartile range 1 to 3; group C: Median 6, interquartile range 5 to 7; p = 0.000), and the NRS score of postoperative pain while coughing was significantly lower in group P (group P: Median 5, interquartile range 3.5 to 6.5; group C: Median 8, interquartile range 7 to 10; p = 0.000). Reintubation rate was significantly lower in group P (group P: 0%, group C: 23%, p = 0.045); the incidences of NPPV (group P: 12%, group C: 46%, p = 0.016) and postoperative pneumonia were significantly lower in group P (group P: 0%, group C: 28%, p = 0.024). CONCLUSIONS: PVB significantly reduced postoperative pain at rest and while coughing and significantly reduced the reintubation rate, the rate of NPPV use, and postoperative pneumonia without complications. PVB could be a safe and an effective analgesic method that reduces postoperative respiratory exacerbation in patients who undergo TAAA repair.


Assuntos
Aneurisma da Aorta Torácica/tratamento farmacológico , Aneurisma da Aorta Torácica/cirurgia , Heparina/administração & dosagem , Cuidados Intraoperatórios/métodos , Bloqueio Nervoso/métodos , Procedimentos Cirúrgicos Torácicos/efeitos adversos , Adulto , Idoso , Aneurisma da Aorta Torácica/diagnóstico por imagem , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/diagnóstico por imagem , Dor Pós-Operatória/prevenção & controle , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia
16.
J Neurosci ; 35(1): 84-95, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25568105

RESUMO

The question of how intensive motor training restores motor function after brain damage or stroke remains unresolved. Here we show that the ipsilesional ventral premotor cortex (PMv) and perilesional primary motor cortex (M1) of rhesus macaque monkeys are involved in the recovery of manual dexterity after a lesion of M1. A focal lesion of the hand digit area in M1 was made by means of ibotenic acid injection. This lesion initially caused flaccid paralysis in the contralateral hand but was followed by functional recovery of hand movements, including precision grip, during the course of daily postlesion motor training. Brain imaging of regional cerebral blood flow by means of H2 (15)O-positron emission tomography revealed enhanced activity of the PMv during the early postrecovery period and increased functional connectivity within M1 during the late postrecovery period. The causal role of these areas in motor recovery was confirmed by means of pharmacological inactivation by muscimol during the different recovery periods. These findings indicate that, in both the remaining primary motor and premotor cortical areas, time-dependent plastic changes in neural activity and connectivity are involved in functional recovery from the motor deficit caused by the M1 lesion. Therefore, it is likely that the PMv, an area distant from the core of the lesion, plays an important role during the early postrecovery period, whereas the perilesional M1 contributes to functional recovery especially during the late postrecovery period.


Assuntos
Força da Mão/fisiologia , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiologia , Destreza Motora/fisiologia , Plasticidade Neuronal/fisiologia , Recuperação de Função Fisiológica/fisiologia , Animais , Macaca mulatta , Masculino , Tomografia por Emissão de Pósitrons/métodos , Fatores de Tempo
17.
Eur J Neurosci ; 41(1): 97-108, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25354166

RESUMO

Genetically targeted approaches that permit acute and reversible manipulation of neuronal circuit activity have enabled an unprecedented understanding of how discrete neuronal circuits control animal behavior. Zebra finch singing behavior has emerged as an excellent model for studying neuronal circuit mechanisms underlying the generation and learning of behavioral motor sequences. We employed a newly developed, reversible, neuronal silencing system in zebra finches to test the hypothesis that ensembles of neurons in the robust nucleus of the arcopallium (RA) control the acoustic structure of specific song parts, but not the timing nor the order of song elements. Subunits of an ivermectin-gated chloride channel were expressed in a subset of RA neurons, and ligand administration consistently suppressed neuronal excitability. Suppression of activity in a group of RA neurons caused the birds to sing songs with degraded elements, although the order of song elements was unaffected. Furthermore some syllables disappeared in the middle or at the end of song motifs. Thus, our data suggest that generation of specific song parts is controlled by a subset of RA neurons, whereas elements order coordination and timing of whole songs are controlled by a higher premotor area.


Assuntos
Tentilhões/fisiologia , Córtex Motor/fisiopatologia , Neurônios/fisiologia , Vocalização Animal/fisiologia , Potenciais de Ação/fisiologia , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Dependovirus/genética , Inativação Gênica , Vetores Genéticos , Ivermectina/farmacologia , Masculino , Córtex Motor/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurotransmissores/farmacologia , Técnicas de Patch-Clamp , Espectrografia do Som , Técnicas de Cultura de Tecidos , Transfecção , Vocalização Animal/efeitos dos fármacos
18.
Neuron ; 80(1): 51-63, 2013 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-24094102

RESUMO

What causes critical periods (CPs) to open? For the best-studied case, ocular dominance plasticity in primary visual cortex in response to monocular deprivation (MD), the maturation of inhibition is necessary and sufficient. How does inhibition open the CP? We present a theory: the transition from pre-CP to CP plasticity arises because inhibition preferentially suppresses responses to spontaneous relative to visually driven input activity, switching learning cues from internal to external sources. This differs from previous proposals in (1) arguing that the CP can open without changes in plasticity mechanisms when activity patterns become more sensitive to sensory experience through circuit development, and (2) explaining not simply a transition from no plasticity to plasticity, but a change in outcome of MD-induced plasticity from pre-CP to CP. More broadly, hierarchical organization of sensory-motor pathways may develop through a cascade of CPs induced as circuit maturation progresses from "lower" to "higher" cortical areas.


Assuntos
Dominância Ocular , Plasticidade Neuronal/fisiologia , Córtex Visual/fisiologia , Animais , Período Crítico Psicológico , Aprendizagem/fisiologia , Camundongos , Inibição Neural/fisiologia , Estimulação Luminosa/métodos , Privação Sensorial/fisiologia , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Vias Visuais/fisiologia
19.
PLoS One ; 8(5): e65701, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23741508

RESUMO

We previously reported that secreted phosphoprotein 1 (SPP1) mRNA is expressed in neurons whose axons form the corticospinal tract (CST) of the rhesus macaque, but not in the corresponding neurons of the marmoset and rat. This suggests that SPP1 expression is involved in the functional or structural specialization of highly developed corticospinal systems in certain primate species. To further examine this hypothesis, we evaluated the expression of SPP1 mRNA in the motor cortex from three viewpoints: species differences, postnatal development, and functional/structural changes of the CST after a lesion of the lateral CST (l-CST) at the mid-cervical level. The density of SPP1-positive neurons in layer V of the primary motor cortex (M1) was much greater in species with highly developed corticospinal systems (i.e., rhesus macaque, capuchin monkey, and humans) than in those with less developed corticospinal systems (i.e., squirrel monkey, marmoset, and rat). SPP1-positive neurons in the macaque monkey M1 increased logarithmically in layer V during postnatal development, following a time course consistent with the increase in conduction velocity of the CST. After an l-CST lesion, SPP1-positive neurons increased in layer V of the ventral premotor cortex, in which compensatory changes in CST function/structure may occur, which positively correlated with the extent of finger dexterity recovery. These results further support the concept that the expression of SPP1 may reflect functional or structural specialization of highly developed corticospinal systems in certain primate species.


Assuntos
Regulação da Expressão Gênica , Córtex Motor/metabolismo , Osteopontina/genética , Recuperação de Função Fisiológica , Idoso , Idoso de 80 Anos ou mais , Animais , Humanos , Córtex Motor/lesões , Osteopontina/metabolismo , Primatas , Tratos Piramidais/metabolismo , Tratos Piramidais/fisiopatologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Especificidade da Espécie
20.
J Neurophysiol ; 109(12): 2853-65, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23515793

RESUMO

Dexterous hand movements can be restored with motor rehabilitative training after a lesion of the lateral corticospinal tract (l-CST) in macaque monkeys. To maximize effectiveness, the optimal time to commence such rehabilitative training must be determined. We conducted behavioral analyses and compared the recovery of dexterous hand movements between monkeys in which hand motor training was initiated immediately after the l-CST lesion (early-trained monkeys) and those in which training was initiated 1 mo after the lesion (late-trained monkeys). The performance of dexterous hand movements was evaluated by food retrieval tasks. In early-trained monkeys, performance evaluated by the success rate in a vertical slit task (retrieval of a small piece of food through a narrow vertical slit) recovered to the level of intact monkeys during the first 1-2 mo after the lesion. In late-trained monkeys, the task success rate averaged ∼30% even after 3 mo of rehabilitative training. We also evaluated hand performance with the Klüver board task, in which monkeys retrieved small spherical food pellets from cylindrical wells. Although the success rate of the Klüver board task did not differ between early- and late-trained monkeys, kinematic movement analysis showed that there was a difference between the groups: late-trained monkeys with an improved success rate frequently used alternate movement strategies that were different from those used before the lesion. These results suggest that early rehabilitative training after a spinal cord lesion positively influences subsequent functional recovery.


Assuntos
Mãos/fisiologia , Destreza Motora , Tratos Piramidais/fisiopatologia , Traumatismos da Medula Espinal/reabilitação , Animais , Fenômenos Biomecânicos , Mãos/inervação , Macaca mulatta , Fatores de Tempo
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