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1.
Hum Brain Mapp ; 45(8): e26723, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38864296

RESUMO

This study aims to investigate the structural reorganization in the sensorimotor area of the brain in patients with gliomas, distinguishing between those with impaired and unimpaired strength. Using voxel-based morphometry (VBM) and region of interest (ROI) analysis, gray matter volumes (GMV) were compared in the contralesional primary motor gyrus, primary sensory gyrus, premotor area, bilateral supplementary motor area, and medial Brodmann area 8 (BA8). The results revealed that in patients with right hemisphere gliomas, the right medial BA8 volume was significantly larger in the impaired group than in the unimpaired group, with both groups exceeding the volume in 16 healthy controls (HCs). In patients with left hemisphere gliomas, the right supplementary motor area (SMA) was more pronounced in the impaired group compared to the unimpaired group, and both groups were greater than HCs. Additionally, the volumes of the right medial BA8 in both the impaired group were greater than HCs. Contralateral expansions in the gray matter of hand- and trunk-related cortices of the premotor area, precentral gyrus, and postcentral gyrus were observed compared to HCs. Furthermore, a negative correlation was found between hand Medical Research Council (MRC) score and volumes of the contralateral SMA and bilateral medial BA8. Notably, our findings reveal consistent results across both analytical approaches in identifying significant structural reorganizations within the sensorimotor cortex. These consistent findings underscore the adaptive neuroplastic responses to glioma presence, highlighting potential areas of interest for further neurosurgical planning and rehabilitation strategies.


Assuntos
Neoplasias Encefálicas , Lateralidade Funcional , Glioma , Imageamento por Ressonância Magnética , Córtex Sensório-Motor , Humanos , Masculino , Glioma/diagnóstico por imagem , Glioma/patologia , Glioma/fisiopatologia , Feminino , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Adulto , Pessoa de Meia-Idade , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/patologia , Córtex Sensório-Motor/fisiopatologia , Lateralidade Funcional/fisiologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Córtex Motor/diagnóstico por imagem , Córtex Motor/patologia , Córtex Motor/fisiopatologia , Mapeamento Encefálico , Adulto Jovem
2.
Exp Brain Res ; 240(12): 3183-3192, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36260096

RESUMO

Body representation disorders are complex, varied, striking, and very disabling in most cases. Deficits of body representation have been described after lesions to multimodal and sensorimotor cortical areas. A few studies have reported the effects of tumors on the representation of the body, but little is known about the changes after tumor resection. Moreover, the impact of brain lesions on the hand size representation has been investigated in few clinical cases. Hands are of special importance, as no other body part has the ability for movement and interaction with the environment that the hands have, and we use them for a multitude of daily activities. Studies with clinical population can add further knowledge into the way hands are represented. Here, we report a single case study of a patient (AM) who was an expert bodybuilder and underwent a surgery to remove a glioblastoma in the left posterior prefrontal and precentral cortex at the level of the hand's motor region. Pre- (20 days) and post- (4 months) surgery assessment did not show any motor or cognitive impairments. A hand localization task was used, before and after surgery (12 months), to measure possible changes of the metric representation of his right hand. Results showed a post-surgery modulation of the typically distorted hand representation, with an overall accuracy improvement, especially on width dimension. These findings support the direct involvement of sensorimotor areas in the implicit representation of the body size and its relevance on defining specific size representation dimensions.


Assuntos
Imagem Corporal , Neoplasias Encefálicas , Glioblastoma , Mãos , Procedimentos Neurocirúrgicos , Córtex Sensório-Motor , Humanos , Imagem Corporal/psicologia , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/psicologia , Neoplasias Encefálicas/cirurgia , Mãos/fisiopatologia , Movimento/fisiologia , Córtex Sensório-Motor/fisiopatologia , Glioblastoma/fisiopatologia , Glioblastoma/psicologia , Glioblastoma/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/psicologia , Tamanho Corporal
3.
J Neurosci ; 41(47): 9844-9858, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34702744

RESUMO

Tremor, a common and often primary symptom of Parkinson's disease, has been modeled with distinct onset and maintenance dynamics. To identify the neurophysiologic correlates of each state, we acquired intraoperative cortical and subthalamic nucleus recordings from 10 patients (9 male, 1 female) performing a naturalistic visual-motor task. From this task, we isolated short epochs of tremor onset and sustained tremor. Comparing these epochs, we found that the subthalamic nucleus was central to tremor onset, as it drove both motor cortical activity and tremor output. Once tremor became sustained, control of tremor shifted to cortex. At the same time, changes in directed functional connectivity across sensorimotor cortex further distinguished the sustained tremor state.SIGNIFICANCE STATEMENT Tremor is a common symptom of Parkinson's disease (PD). While tremor pathophysiology is thought to involve both basal ganglia and cerebello-thalamic-cortical circuits, it is unknown how these structures functionally interact to produce tremor. In this article, we analyzed intracranial recordings from the subthalamic nucleus and sensorimotor cortex in patients with PD undergoing deep brain stimulation surgery. Using an intraoperative task, we examined tremor in two separate dynamic contexts: when tremor first emerged, and when tremor was sustained. We believe that these findings reconcile several models of Parkinson's tremor, while describing the short-timescale dynamics of subcortical-cortical interactions during tremor for the first time. These findings may describe a framework for developing proactive and responsive neurostimulation models for specifically treating tremor.


Assuntos
Vias Neurais/fisiopatologia , Doença de Parkinson/fisiopatologia , Córtex Sensório-Motor/fisiopatologia , Núcleo Subtalâmico/fisiopatologia , Tremor/fisiopatologia , Idoso , Eletrocorticografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Tremor/etiologia
4.
Neurosci Lett ; 761: 136120, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34280504

RESUMO

Exposure to nicotine during adolescence may cause neurophysiological changes and increase the risks of developing nicotine dependence; it can even lead to lifelong smoking. The intake of nicotine may also lead to abnormal patterns of oscillatory brain activity and inhibition control deficits. However, little is known about the specific relationship between oscillatory brain activity during the resting state and inhibition control capacity in young smokers. In the present study, we acquired resting-state electroencephalography (EEG) data from thirty-four young smokers and 39 age-matched non-smoking controls. Inhibition control performance was measured by a Go/NoGo task. Compared with non-smoking controls, we detected reduced low-frequency delta band activity in the frontal, central and posterior cortices of young smokers. Furthermore, young smokers committed more errors in response to infrequent NoGo trials. Notably, we demonstrated that delta absolute power in the frontal region was negatively correlated with NoGo errors and that alpha power in the central region was positively correlated with NoGo errors in non-smoking controls but not in young smokers. These findings may suggest that these inhibitory control processes were associated with alterations in oscillatory brain activity during the resting state. Our findings suggest that alterations of power spectra in delta bands may act as a useful biomarker of inhibitory control performance and provide a scientific basis for the diagnosis and treatment of nicotine addiction in adolescents.


Assuntos
Ondas Encefálicas , Inibição Neural , Fumar Tabaco/fisiopatologia , Humanos , Masculino , Córtex Sensório-Motor/fisiopatologia , Adulto Jovem
5.
Neurorehabil Neural Repair ; 35(6): 501-512, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33825570

RESUMO

BACKGROUND: Very early exercise has been reported to exacerbate motor dysfunction; however, its mechanism is largely unknown. OBJECTIVE: This study examined the effect of very early exercise on motor recovery and associated brain damage following intracerebral hemorrhage (ICH) in rats. METHODS: Collagenase solution was injected into the left striatum to induce ICH. Rats were randomly assigned to receive placebo surgery without exercise (SHAM) or ICH without (ICH) or with very early exercise within 24 hours of surgery (ICH+VET). We observed sensorimotor behaviors before surgery, and after surgery preexercise and postexercise. Postexercise brain tissue was collected 27 hours after surgery to investigate the hematoma area, brain edema, and Il1b, Tgfb1, and Igf1 mRNA levels in the striatum and sensorimotor cortex using real-time reverse transcription polymerase chain reaction. NeuN, PSD95, and GFAP protein expression was analyzed by Western blotting. RESULTS: We observed significantly increased skillful sensorimotor impairment in the horizontal ladder test and significantly higher Il1b mRNA levels in the striatum of the ICH+VET group compared with the ICH group. NeuN protein expression was significantly reduced in both brain regions of the ICH+VET group compared with the SHAM group. CONCLUSION: Our results suggest that very early exercise may be associated with an exacerbation of motor dysfunction because of increased neuronal death and region-specific changes in inflammatory factors. These results indicate that implementing exercise within 24 hours after ICH should be performed with caution.


Assuntos
Hemorragia Cerebral , Terapia por Exercício/efeitos adversos , Atividade Motora/fisiologia , Doenças Neuroinflamatórias , Reabilitação Neurológica , Condicionamento Físico Animal/fisiologia , Animais , Comportamento Animal/fisiologia , Hemorragia Cerebral/imunologia , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/reabilitação , Corpo Estriado/imunologia , Corpo Estriado/metabolismo , Corpo Estriado/fisiopatologia , Modelos Animais de Doenças , Masculino , Doenças Neuroinflamatórias/etiologia , Doenças Neuroinflamatórias/imunologia , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/fisiopatologia , Distribuição Aleatória , Ratos , Ratos Wistar , Córtex Sensório-Motor/imunologia , Córtex Sensório-Motor/metabolismo , Córtex Sensório-Motor/fisiopatologia
6.
Medicine (Baltimore) ; 100(3): e24302, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33546056

RESUMO

RATIONALE: Cortical deafness is a rare auditory dysfunction caused by damage to brain auditory networks. The aim was to report alterations of functional connectivity in intrinsic auditory, motor, and sensory networks in a cortical deafness patient. PATIENT CONCERNS: A 41-year-old woman suffered a right putaminal hemorrhage. Eight years earlier, she had suffered a left putaminal hemorrhage and had minimal sequelae. She had quadriparesis, imbalance, hypoesthesia, and complete hearing loss. DIAGNOSES: She was diagnosed with cortical deafness. After 6 months, resting-state functional magnetic resonance imaging (rs-fMRI) and diffuse tensor imaging (DTI) were performed. DTI revealed that the acoustic radiation was disrupted while the corticospinal tract and somatosensory track were intact using deterministic tracking methods. Furthermore, the patient showed decreased functional connectivity between auditory and sensorimotor networks. INTERVENTIONS: The patient underwent in-patient stroke rehabilitation therapy for 2 months. OUTCOMES: Gait function and ability for activities of daily living were improved. However, complete hearing impairment persisted in 6 months after bilateral putaminal hemorrhagic stroke. LESSONS: Our case report seems to suggest that functional alterations of spontaneous neuronal activity in auditory and sensorimotor networks are related to motor and sensory impairments in a patient with cortical deafness.


Assuntos
Córtex Auditivo/anormalidades , Perda Auditiva Central/etiologia , Rede Nervosa/anormalidades , Córtex Sensório-Motor/anormalidades , Adulto , Córtex Auditivo/fisiopatologia , Feminino , Perda Auditiva Central/fisiopatologia , Acidente Vascular Cerebral Hemorrágico/complicações , Acidente Vascular Cerebral Hemorrágico/fisiopatologia , Humanos , Testes de Estado Mental e Demência , Rede Nervosa/fisiopatologia , Hemorragia Putaminal/complicações , Hemorragia Putaminal/fisiopatologia , Córtex Sensório-Motor/fisiopatologia
7.
Behav Brain Res ; 405: 113197, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33621609

RESUMO

BACKGROUND: Conditional deletion of Pten in corticospinal neurons promotes axon sprouting and regeneration after spinal cord injury (SCI). However, regeneration studies targeted on PTEN inhibition seldom show motor function recovery. The promotion of functional recovery can be improved by rehabilitative training under a use-dependent plasticity mechanism. PURPOSE: To investigate the combined effects of PTEN inhibition and rehabilitative training on axon regeneration and subsequent motor functional improvement after cervical spinal cord injury. METHODS: Lentiviral particles (Lenti-PTEN-RNAi or Lenti-Scrambled-EGFP) were injected into the right sensorimotor mouse cortex in four experimental groups (PTEN RNAi + Training, PTEN RNAi, Control + Training, Control). Two weeks after injection, all mouse groups received a left C5 crush injury. We performed task-based rehabilitative training for 4 weeks on the PTEN RNAi + Training and Control + Training groups. Biotinylated dextran amine (BDA) was used for anterograde tracing of the dorsal corticospinal tract (dCST). We analysed axonal regeneration through immunohistochemical methods. A battery of behavioral tests was employed to assess functional recovery at Day3 and every other week after injury. RESULTS: Combining rehabilitative training with PTEN inhibition induced more axon regeneration and synapse reformation in the spinal cord caudal to the lesion site. Rostral to the lesion, the transected dCST axons sprouted into gray matter upon contact. Furthermore, forelimb function was found to be improved after combination therapy during behavioral testing. CONCLUSION: Combining task-based rehabilitative training with PTEN inhibition further promotes axon regeneration, synaptic plasticity and reorganization of the neural network, with significant improvement in forelimb skilled motor function after cervical spinal cord injury. Our study provides new therapeutic insights for spinal cord injury management in the future.


Assuntos
Axônios/fisiologia , Medula Cervical/lesões , Destreza Motora/fisiologia , Regeneração Nervosa/fisiologia , Reabilitação Neurológica , PTEN Fosfo-Hidrolase , Terapêutica com RNAi , Recuperação de Função Fisiológica/fisiologia , Córtex Sensório-Motor/fisiopatologia , Traumatismos da Medula Espinal/terapia , Extremidade Superior/fisiopatologia , Animais , Comportamento Animal/fisiologia , Terapia Combinada , Modelos Animais de Doenças , Feminino , Lentivirus , Camundongos , Camundongos Endogâmicos C57BL , PTEN Fosfo-Hidrolase/genética , Traumatismos da Medula Espinal/reabilitação
8.
Neuroimage ; 224: 117403, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979521

RESUMO

Lifestyle dietary interventions are an essential practice in treating obesity, hence neural factors that may assist in predicting individual treatment success are of great significance. Here, in a prospective, open-label, three arms study, we examined the correlation between brain resting-state functional connectivity measured at baseline and weight loss following 6 months of lifestyle intervention in 92 overweight participants. We report a robust subnetwork composed mainly of sensory and motor cortical regions, whose edges correlated with future weight loss. This effect was found regardless of intervention group. Importantly, this main finding was further corroborated using a stringent connectivity-based prediction model assessed with cross-validation thus attesting to its robustness. The engagement of senso-motor regions in this subnetwork is consistent with the over-sensitivity to food cues theory of weight regulation. Finally, we tested an additional hypothesis regarding the role of brain-gastric interaction in this subnetwork, considering recent findings of a cortical network synchronized with gastric activity. Accordingly, we found a significant spatial overlap with the subnetwork reported in the present study. Moreover, power in the gastric basal electric frequency within our reported subnetwork negatively correlated with future weight loss. This finding was specific to the weight loss related subnetwork and to the gastric basal frequency. These findings should be further corroborated by combining direct recordings of gastric activity in future studies. Taken together, these intriguing results may have important implications for our understanding of the etiology of obesity and the mechanism of response to dietary intervention.


Assuntos
Encéfalo/diagnóstico por imagem , Dieta Mediterrânea , Obesidade/dietoterapia , Córtex Sensório-Motor/diagnóstico por imagem , Redução de Peso , Adulto , Encéfalo/fisiopatologia , Regras de Decisão Clínica , Conectoma , Exercício Físico , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Obesidade/fisiopatologia , Sobrepeso/dietoterapia , Sobrepeso/fisiopatologia , Polifenóis , Córtex Sensório-Motor/fisiopatologia , Estômago/fisiopatologia , Resultado do Tratamento
9.
Acta Neuropathol Commun ; 8(1): 193, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33183353

RESUMO

Frequently reported neurotoxic sequelae of cancer treatment include cognitive deficits and sensorimotor abnormalities that have long-lasting negative effects on the quality of life of an increasing number of cancer survivors. The underlying mechanisms are not fully understood and there is no effective treatment. We show here that cisplatin treatment of mice not only caused cognitive dysfunction but also impaired sensorimotor function. These functional deficits are associated with reduced myelin density and complexity in the cingulate and sensorimotor cortex. At the ultrastructural level, myelin abnormalities were characterized by decompaction. We used this model to examine the effect of bexarotene, an agonist of the RXR-family of nuclear receptors. Administration of only five daily doses of bexarotene after completion of cisplatin treatment was sufficient to normalize myelin density and fiber coherency and to restore myelin compaction in cingulate and sensorimotor cortex. Functionally, bexarotene normalized performance of cisplatin-treated mice in tests for cognitive and sensorimotor function. RNAseq analysis identified the TR/RXR pathway as one of the top canonical pathways activated by administration of bexarotene to cisplatin-treated mice. Bexarotene also activated neuregulin and netrin pathways that are implicated in myelin formation/maintenance, synaptic function and axonal guidance. In conclusion, short term treatment with bexarotene is sufficient to reverse the adverse effects of cisplatin on white matter structure, cognitive function, and sensorimotor performance. These encouraging findings warrant further studies into potential clinical translation and the underlying mechanisms of bexarotene for chemobrain.


Assuntos
Antineoplásicos/farmacologia , Bexaroteno/farmacologia , Cisplatino/toxicidade , Cognição/efeitos dos fármacos , Giro do Cíngulo/efeitos dos fármacos , Bainha de Mielina/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Córtex Sensório-Motor/efeitos dos fármacos , Animais , Antineoplásicos/toxicidade , Comprometimento Cognitivo Relacionado à Quimioterapia/metabolismo , Comprometimento Cognitivo Relacionado à Quimioterapia/patologia , Comprometimento Cognitivo Relacionado à Quimioterapia/fisiopatologia , Marcha/efeitos dos fármacos , Perfilação da Expressão Gênica , Giro do Cíngulo/metabolismo , Giro do Cíngulo/patologia , Giro do Cíngulo/fisiopatologia , Camundongos , Bainha de Mielina/metabolismo , Bainha de Mielina/patologia , Bainha de Mielina/ultraestrutura , Netrinas/efeitos dos fármacos , Netrinas/genética , Netrinas/metabolismo , Neurregulinas/efeitos dos fármacos , Neurregulinas/genética , Neurregulinas/metabolismo , Teste de Campo Aberto , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/fisiopatologia , RNA-Seq , Receptores X de Retinoides/efeitos dos fármacos , Receptores X de Retinoides/genética , Receptores X de Retinoides/metabolismo , Córtex Sensório-Motor/metabolismo , Córtex Sensório-Motor/patologia , Córtex Sensório-Motor/fisiopatologia , Substância Branca/efeitos dos fármacos , Substância Branca/metabolismo , Substância Branca/patologia
10.
Clin Neurophysiol ; 131(8): 1691-1701, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32504928

RESUMO

OBJECTIVE: We evaluated stereo-EEG electrical stimulation mapping (ESM) for localization of anatomic sensorimotor parcels in pediatric patients with drug-resistant epilepsy. We also analyzed sensorimotor and after-discharge thresholds, and the somatotopy of sensorimotor responses. METHODS: ESM was performed with 50 Hz, biphasic, 2-3 s trains, using 1-9 mA current. Pre- and post-implant neuroimaging was co-registered and intersected with Neurosynth reference, to classify each electrode contact as lying within/outside an anatomic sensorimotor parcel. Indices of diagnostic performance were computed. Sensorimotor and after-discharge thresholds were analyzed using multivariable linear mixed models. RESULTS: In 15 patients (6 females), aged 5.5-21.2 years, ESM showed high accuracy (0.80), high specificity (0.86), and diagnostic odds ratio (11.4, p < 0.0001) for localization of sensorimotor parcels. Mean sensorimotor threshold (3.4 mA) was below mean after-discharge threshold (4.2 mA, p = 0.0004). Sensorimotor and after-discharge thresholds showed a significant decrease with increasing intelligence quotient. Somatotopy of sensorimotor responses was mapped to standardized brain parcels. CONCLUSIONS: We provide evidence for diagnostic validity and safety of stereo-EEG sensorimotor ESM. SIGNIFICANCE: The somatotopy of sensorimotor responses elicited with electrical stimulation provide new insights into mechanisms of motor control and sensory perception.


Assuntos
Mapeamento Encefálico/métodos , Epilepsia Resistente a Medicamentos/fisiopatologia , Eletroencefalografia/métodos , Córtex Sensório-Motor/fisiopatologia , Adolescente , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Estimulação Elétrica , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Sensibilidade e Especificidade , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/cirurgia , Adulto Jovem
11.
Neuroimaging Clin N Am ; 30(2): 159-174, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32336404

RESUMO

Noninvasive functional brain imaging with magnetoencephalography (MEG) is regularly used to map the eloquent cortex associated with somatosensory, motor, auditory, visual, and language processing before a surgical resection to determine if the functional areas have been reorganized. Most tasks can also be performed in the pediatric population. To acquire an optimal MEG study for any of these modalities, the patient needs to be well rested and attending to the stimulation.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/fisiopatologia , Magnetoencefalografia , Mapeamento Encefálico , Neoplasias Encefálicas/cirurgia , Humanos , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/fisiopatologia
12.
Transl Stroke Res ; 11(1): 93-107, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-30747366

RESUMO

Stroke is one of the leading causes of long-term disability. Cell transplantation is a promising strategy to treat stroke. We explored the efficacy of directly reprogrammed human neural precursor cell (drNPC) transplants to promote functional recovery in a model of focal ischemic stroke in the mouse sensorimotor cortex. We show that drNPCs express neural precursor cell markers and are neurally committed at the time of transplantation. Mice that received drNPC transplants recovered motor function, irrespective of transplant vehicle or recipient sex, and with no correlation to lesion volume or glial scarring. The majority of drNPCs found in vivo, at the time of functional recovery, remained undifferentiated. Notably, no correlation between functional recovery and long-term xenograft survival was observed, indicating that drNPCs provide therapeutic benefits beyond their survival. Furthermore, increased synaptophysin expression in transplanted brains suggests that drNPCs promote neuroplasticity through enhanced synaptogenesis. Our findings provide insight into the mechanistic underpinnings of drNPC-mediated recovery for stroke and support the notion that drNPCs may have clinical applications for stroke therapy.


Assuntos
Isquemia Encefálica/fisiopatologia , AVC Isquêmico/fisiopatologia , Células-Tronco Neurais/fisiologia , Células-Tronco Neurais/transplante , Córtex Sensório-Motor/fisiopatologia , Sinapses/fisiologia , Animais , Feminino , Humanos , Masculino , Camundongos , Recuperação de Função Fisiológica
13.
Neurology ; 93(2): e116-e124, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31197032

RESUMO

OBJECTIVE: To assess with magnetoencephalography the developmental vs progressive character of the impairment of spinocortical proprioceptive pathways in Friedreich ataxia (FRDA). METHODS: Neuromagnetic signals were recorded from 16 right-handed patients with FRDA (9 female patients, mean age 27 years, mean Scale for the Assessment and Rating Of ataxia [SARA] score 22.25) and matched healthy controls while they performed right finger movements either actively or passively. The coupling between movement kinematics (i.e., acceleration) and neuromagnetic signals was assessed by the use of coherence at sensor and source levels. Such coupling, that is, the corticokinematic coherence (CKC), specifically indexes proprioceptive afferent inputs to the contralateral primary sensorimotor (cSM1) cortex. Nonparametric permutations and Spearman rank correlation test were used for statistics. RESULTS: In both groups of participants and movement conditions, significant coupling peaked at the cSM1 cortex. Coherence levels were 70% to 75% lower in patients with FRDA than in healthy controls in both movement conditions. In patients with FRDA, coherence levels correlated with genotype alteration (i.e., the size of GAA1 triplet expansion) and the age at symptom onset but not with disease duration or SARA score. CONCLUSION: This study provides electrophysiologic evidence demonstrating that proprioceptive impairment in FRDA is mostly genetically determined and scarcely progressive after symptom onset. It also positions CKC as a reliable, robust, specific marker of proprioceptive impairment in FRDA.


Assuntos
Vias Aferentes/fisiopatologia , Ataxia de Friedreich/fisiopatologia , Propriocepção , Córtex Sensório-Motor/fisiopatologia , Adolescente , Adulto , Idade de Início , Estudos de Casos e Controles , Criança , Feminino , Dedos , Ataxia de Friedreich/genética , Genótipo , Humanos , Proteínas de Ligação ao Ferro/genética , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiopatologia , Índice de Gravidade de Doença , Fatores de Tempo , Expansão das Repetições de Trinucleotídeos , Adulto Jovem , Frataxina
14.
Neuroimage Clin ; 23: 101819, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31009885

RESUMO

Cigarette smokers have shown hypersensitivity to reward and hyposensitivity to punishment, along with impairments in learning from errors. The underlying neural mechanism for this failure to adapt performance following an error, particularly when receiving negative feedback, are unclear. Smokers were hypothesized to have poorer error-learning following monetary punishment, associated with hypoactivation in the insula, dorsal anterior cingulate, and hippocampal cortical regions. Twenty-three smokers (8 females, mean age = 25.48, SD = 4.46) and twenty-three healthy controls (13 females, mean age = 24.83, SD = 5.99) were administered an associative learning task, providing monetary reward and punishment for recall performance, during fMRI data collection. Compared with controls, smokers had a lower error-correction rate and were less sensitive to punishment magnitude. Hyperactivity during recall was independent of future error correction, but smokers' successful re-encoding appeared related to higher dorsolateral prefrontal cortex activity while controls had equivalent activation for corrected and repeated errors. While controls showed higher deactivation of the sensorimotor cortex during high punishment, smokers showed higher deactivation during low punishment. The present results support smokers having poorer learning from errors and decreased attentional control associated with hyperactivity in the dorsolateral prefrontal cortex. Additionally, smokers exhibited decreased punishment sensitivity that appeared to limit their ability to adapt learning in the face of repeated negative feedback.


Assuntos
Aprendizagem por Associação/fisiologia , Córtex Pré-Frontal/fisiopatologia , Punição , Córtex Sensório-Motor/fisiopatologia , Fumantes/psicologia , Fumar/fisiopatologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Recompensa , Adulto Jovem
15.
Bull Exp Biol Med ; 166(3): 364-368, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30627904

RESUMO

Post-weaning social isolation of male Wistar rats for 10 weeks led to an increase of their aggressiveness, sensorimotor reactivity, and cognitive deficiency, manifesting in training disorders evaluated by the acoustic startle response (amplitude of the response decreasing). Expression of gene encoding serine protease prolyl endopeptidase (EC 3.4.21.26) in the frontal cortex was higher than in control rats kept in groups, while the level of mRNA of the gene encoding dipeptidyl peptidase IV (EC 3.4.14.5) did not differ from the control in any of the brain structures. The levels of serotonin transporter gene mRNA in the striatum and hypothalamus were higher than in the control. No appreciable changes in the expression of genes encoding tryptophan hydroxylase-2 and monoaminoxidase A and B in the frontal cortex, striatum, amygdala, hypothalamus, and hippocampus were detected. The data indicated the involvement of genes associated with the serotoninergic system in the mechanisms of mental disorders induced by post-weaning social isolation and suggest the gene encoding prolyl endopeptidase as a candidate gene involved in the pathogenesis of these disorders.


Assuntos
Disfunção Cognitiva/genética , Serina Endopeptidases/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Isolamento Social/psicologia , Estresse Psicológico/genética , Desmame , Agressão/psicologia , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/fisiopatologia , Animais , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Corpo Estriado/metabolismo , Corpo Estriado/fisiopatologia , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Lobo Frontal/metabolismo , Lobo Frontal/fisiopatologia , Regulação da Expressão Gênica , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Hipotálamo/metabolismo , Hipotálamo/fisiopatologia , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Monoaminoxidase/genética , Monoaminoxidase/metabolismo , Atividade Motora/fisiologia , Prolil Oligopeptidases , Ratos , Ratos Wistar , Reflexo de Sobressalto , Córtex Sensório-Motor/metabolismo , Córtex Sensório-Motor/fisiopatologia , Serina Endopeptidases/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , Triptofano Hidroxilase/genética , Triptofano Hidroxilase/metabolismo
16.
Eur J Pain ; 23(3): 483-494, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30288850

RESUMO

BACKGROUND: Sensorimotor conflicts are well known to induce sensory disturbances. However, explanations as to why patients with chronic pain are more sensitive to sensorimotor conflicts remain elusive. The main objectives of this study were (a) to assess and compare the sensory disturbances induced by sensorimotor conflict in complex regional pain syndrome (n = 38), fibromyalgia (n = 36), arthritis (n = 34) as well as in healthy volunteers (HV) (n = 32); (b) to assess whether these disturbances were related to the intensity and duration of pain, or to other clinical variables assessed using questionnaires (abnormalities in sensory perception, depression and anxiety); and (c) to categorize different subgroups of conflict-induced sensory disturbances. METHODS: One hundred and forty participants performed in phase or anti-phase movements with their arms while viewing a reflection of one arm in a mirror (and the other arm obscured). They were asked to report changes in sensory disturbances using a questionnaire. RESULTS: First, results showed that patients with complex regional pain syndrome and fibromyalgia were more prone to report sensory disturbances than arthritis patients and HV in response to conflicts (small effect size). Second, conflict-induced sensory disturbances were correlated with pain intensity (large effect size) and abnormalities in sensory perception (only in the CRPS group) but were not related to the duration of the disease or psychological factors. Finally, we identified two distinct subgroups of conflict-induced sensory disturbances. CONCLUSIONS: Our results suggest that pain lowers the threshold for the detection of sensorimotor conflicts, a phenomenon that could contribute to the maintenance of pain in clinical populations. SIGNIFICANCE: Individuals with complex regional pain syndrome and fibromyalgia were more sensitive to sensorimotor conflicts than arthritis patients and controls. Moreover, conflict-induced sensory disturbances were specific to higher pain intensity and higher sensory abnormalities in all groups, suggesting that pain lowers the threshold for the detection of sensorimotor conflicts.


Assuntos
Artrite/complicações , Síndromes da Dor Regional Complexa/complicações , Fibromialgia/complicações , Dor/etiologia , Sensação/fisiologia , Córtex Sensório-Motor/fisiopatologia , Adulto , Artrite/fisiopatologia , Estudos de Casos e Controles , Síndromes da Dor Regional Complexa/diagnóstico , Síndromes da Dor Regional Complexa/fisiopatologia , Feminino , Fibromialgia/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Dor/fisiopatologia , Dor/psicologia , Inquéritos e Questionários
17.
PLoS One ; 13(11): e0205658, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30439952

RESUMO

The sensorimotor system helps to maintain functional joint stability during movement. After anterior cruciate ligament (ACL) injury and reconstruction, several sensorimotor deficits may arise, including altered proprioception and changes in neuromuscular control. It is still unknown whether the type of autograft used in the reconstruction may influence knee sensorimotor impairments. The aim of this study was to comparatively assess the effects of the hamstring tendon (HT) and bone-patellar tendon-bone (BPTB) ACL reconstruction techniques on knee sensorimotor control 6-12 months post-operation. A total of 83 male subjects participated in this study: 27 healthy participants, 30 BPTB-operated patients and 26 HT-operated patients. Active joint position sense in 3 ranges of motion (90-60°, 60-30°, and 30-0° of knee flexion), isometric steadiness, and onset of muscle activation were used to compare sensorimotor system function between groups. Both operated groups had a small (< 5°) but significant joint position sense error in the 30-0° range when compared to the healthy group. No significant differences were found between the operated and the control groups for isometric steadiness or onset of muscle activation. The results of this study suggest that operated patients present knee proprioceptive deficits independently of surgical technique. Nevertheless, the clinical implications of this impairment are still unknown. It seems that selected surgical approach for ACL reconstruction do not affect functioning of the sensorimotor system to a large degree.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Ligamento Cruzado Anterior/cirurgia , Procedimentos de Cirurgia Plástica , Tendões/cirurgia , Adulto , Ligamento Cruzado Anterior/fisiopatologia , Lesões do Ligamento Cruzado Anterior/fisiopatologia , Reconstrução do Ligamento Cruzado Anterior , Feminino , Humanos , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular/fisiologia , Córtex Sensório-Motor/fisiopatologia , Tendões/fisiopatologia , Adulto Jovem
18.
Proc Natl Acad Sci U S A ; 115(30): 7801-7806, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29997174

RESUMO

What forces direct brain organization and its plasticity? When brain regions are deprived of their input, which regions reorganize based on compensation for the disability and experience, and which regions show topographically constrained plasticity? People born without hands activate their primary sensorimotor hand region while moving body parts used to compensate for this disability (e.g., their feet). This was taken to suggest a neural organization based on functions, such as performing manual-like dexterous actions, rather than on body parts, in primary sensorimotor cortex. We tested the selectivity for the compensatory body parts in the primary and association sensorimotor cortex of people born without hands (dysplasic individuals). Despite clear compensatory foot use, the primary sensorimotor hand area in the dysplasic subjects showed preference for adjacent body parts that are not compensatorily used as effectors. This suggests that function-based organization, proposed for congenital blindness and deafness, does not apply to the primary sensorimotor cortex deprivation in dysplasia. These findings stress the roles of neuroanatomical constraints like topographical proximity and connectivity in determining the functional development of primary cortex even in extreme, congenital deprivation. In contrast, increased and selective foot movement preference was found in dysplasics' association cortex in the inferior parietal lobule. This suggests that the typical motor selectivity of this region for manual actions may correspond to high-level action representations that are effector-invariant. These findings reveal limitations to compensatory plasticity and experience in modifying brain organization of early topographical cortex compared with association cortices driven by function-based organization.


Assuntos
Plasticidade Neuronal , Córtex Sensório-Motor/fisiopatologia , Deformidades Congênitas das Extremidades Superiores/fisiopatologia , Feminino , Humanos , Masculino
19.
J Cancer Res Clin Oncol ; 144(9): 1785-1792, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29943097

RESUMO

INTRODUCTION: Breast cancer is the most common cancer disease of women in industrialized countries. Neurotoxic chemotherapy drugs are known to harm peripheral nerves and cause a chemotherapy-induced peripheral neuropathy (CIPN). CIPN is one of the most common adverse events associated with Paclitaxel chemotherapy and may remain present long after the termination of chemotherapy. Thus, it reduces the patients' quality of life (QoL) both during chemotherapy and onwards, and can impose a danger on breast cancer survivors due to an increased risk of falling and fall-related injuries. METHODS: The aim of this randomized-controlled trial (RCT) (n = 36) (IG: intervention group, n = 17) (CG: control group, n = 19) was to determine whether sensorimotor exercises have a positive effect on physical and psychological parameters in breast cancer patients undergoing neurotoxic chemotherapy (Paclitaxel). RESULTS: As a result, we were able to show significant improvements in postural stability in monopedal stance [left leg 16.17 ± 3.67 vs. 21.55 ± 5.33 (p < 0.001) and right leg 15.14 ± 2.30 vs. 20.85 ± 5.05 (p < 0.001)] and in bipedal stance [T1 vs. T0, - 0.49 (IG) vs. + 1.14 (CG) p = 0.039]. DISCUSSION: These results in posturography correlate with the clinical presentation with intervention group patients scoring significantly better on the Fullerton Advanced Balance Scale [37.71 ± 2.73 vs. 34.47 ± 3.98 (p = 0.004)]. Moderate strength training successfully prevented a strength loss in the IG that was remarkable in the CG (- 1.60 vs. 0.60, p = 0.029). Concerning the psychological parameters assessed via EORTC- and MFI-questionnaires, no significant improvements were found. CONCLUSION: Future studies should focus on the correlation of clinical and posturometry findings and subjective QOL such as the long-term-development of CIPN.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/fisiopatologia , Neoplasias da Mama/psicologia , Exercício Físico/fisiologia , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/fisiopatologia , Córtex Sensório-Motor/fisiopatologia , Adulto , Idoso , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Paclitaxel/uso terapêutico , Doenças do Sistema Nervoso Periférico/psicologia , Qualidade de Vida , Sobreviventes , Adulto Jovem
20.
Biol Trace Elem Res ; 186(2): 441-448, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29574671

RESUMO

In most communities, there is a constant exposure to environmental pollutants with probable negative impact on the development of the nervous system. Among these pollutants are the sodium fluoride (NaF) and aluminum chloride (AlCl3) which may represent a real threat to the proper functioning of the brain. This study comprises two fundamentally different strategies; in the first one, pregnant rats were administered a daily dose of NaF (0.15 g /L) or AlCl3 (500 mg/L) in the drinking water either separately or in combination with each other from day 6 of gestation until just after weaning. In the second approach, the male rats born to mothers exposed to the pollutants were divided into two groups. In the first, rats were continued to be treated with the same pollutants administered to them in the drinking water at the same dose level until the age of 70 days. The rats of the second group were supplied with drinking water without either one of the pollutants for a similar period of time. The rats exposed to NaF separately or in combination with AlCl3 during the prenatal life and subsequently through the postnatal stages exhibited disturbance in the locomotor activities. This was concomitant with alterations in plasma, PTH, ACTH, and estradiol levels. Additionally, the serum levels of LH and testosterone were altered in the two groups treated with sodium fluoride during the prenatal and up to the weaning periods or in the group which continued to have the NaF until day 70 after birth.


Assuntos
Cloreto de Alumínio/toxicidade , Hormônios/sangue , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Córtex Sensório-Motor/efeitos dos fármacos , Fluoreto de Sódio/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Estradiol/sangue , Feminino , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Ratos Wistar , Córtex Sensório-Motor/fisiologia , Córtex Sensório-Motor/fisiopatologia , Testosterona , Desmame
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