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1.
Reumatol. clín. (Barc.) ; 19(3): 168-170, Mar. 2023. ilus
Artigo em Inglês | IBECS | ID: ibc-217291

RESUMO

The chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) and autoimmune/inflammatory syndrome induced by adjuvants (ASIA) were described a decade ago. There are a limited number of reports and these diseases are still underdiagnosed.We presented a 35 years-old patient with clinical manifestations of cerebellum affection and enhancement in the MRI, with the influenza vaccine as the only triggering factor.Infectious diseases, malignancy, and additional systemic involvement were ruled out; therefore, on suspicion of CLIPPERS syndrome, the patient received corticosteroid therapy with an adequate response.The knowledge of CLIPPERS syndrome as an unusual ASIA presentation and high response to the corticosteroids may lead to a timely diagnosis, appropriate treatment, and follow up with better outcomes for patients.(AU)


La inflamación linfocítica crónica con realce perivascular pontino que responde a los esteroides (CLIPPERS) y el síndrome autoinmune/inflamatorio inducido por adyuvantes (ASIA) se describieron hace una década. Hay un número limitado de reportes y estas enfermedades aún están infra diagnosticadas.Presentamos un paciente de 35 años con cuadro clínico de afectación del cerebelo y realce en la RM, con la vacuna anti-influenza como único factor desencadenante.Se descartaron enfermedades infecciosas, malignidad y afectación sistémica, por lo tanto, ante sospecha de síndrome de CLIPPERS, recibió tratamiento con corticoesteroides con una respuesta adecuada.El conocimiento del síndrome de CLIPPERS como una presentación inusual de ASIA y su alta respuesta a los corticosteroides puede conducir a un diagnóstico oportuno, un tratamiento adecuado y un seguimiento con mejores resultados para los pacientes.(AU)


Assuntos
Humanos , Masculino , Adulto , Doenças do Sistema Nervoso , Vacinação/efeitos adversos , Vacinas contra Influenza/efeitos adversos , Corticosteroides , Cerebelo/lesões , Reumatologia , Doenças Reumáticas
2.
Sci Rep ; 12(1): 143, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34996954

RESUMO

Blast exposure can injure brain by multiple mechanisms, and injury attributable to direct effects of the blast wave itself have been difficult to distinguish from that caused by rapid head displacement and other secondary processes. To resolve this issue, we used a rat model of blast exposure in which head movement was either strictly prevented or permitted in the lateral plane. Blast was found to produce axonal injury even with strict prevention of head movement. This axonal injury was restricted to the cerebellum, with the exception of injury in visual tracts secondary to ocular trauma. The cerebellar axonal injury was increased in rats in which blast-induced head movement was permitted, but the pattern of injury was unchanged. These findings support the contentions that blast per se, independent of head movement, is sufficient to induce axonal injury, and that axons in cerebellar white matter are particularly vulnerable to direct blast-induced injury.


Assuntos
Axônios/patologia , Traumatismos por Explosões/patologia , Lesões Encefálicas Traumáticas/patologia , Cerebelo/patologia , Degeneração Neural , Substância Branca/patologia , Animais , Axônios/metabolismo , Biomarcadores/metabolismo , Traumatismos por Explosões/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Cerebelo/lesões , Cerebelo/metabolismo , Modelos Animais de Doenças , Movimentos da Cabeça , Masculino , Nervo Óptico/metabolismo , Nervo Óptico/patologia , Traumatismos do Nervo Óptico/metabolismo , Traumatismos do Nervo Óptico/patologia , Ratos Long-Evans , Vias Visuais/lesões , Vias Visuais/metabolismo , Vias Visuais/patologia , Substância Branca/lesões , Substância Branca/metabolismo
3.
J Neurosci ; 41(42): 8725-8741, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34462307

RESUMO

Galanin, one of the most inducible neuropeptides, is widely present in developing brains, and its expression is altered by pathologic events (e.g., epilepsy, ischemia, and axotomy). The roles of galanin in brain development under both normal and pathologic conditions have been hypothesized, but the question of how galanin is involved in fetal and early postnatal brain development remains largely unanswered. In this study, using granule cell migration in the cerebellum of early postnatal mice (both sexes) as a model system, we examined the role of galanin in neuronal cell migration during normal development and after brain injury. Here we show that, during normal development, endogenous galanin participates in accelerating granule cell migration via altering the Ca2+ and cAMP signaling pathways. Upon brain injury induced by the application of cold insults, galanin levels decrease at the lesion sites, but increase in the surroundings of lesion sites. Granule cells exhibit the following corresponding changes in migration: (1) slowing down migration at the lesion sites; and (2) accelerating migration in the surroundings of lesion sites. Experimental manipulations of galanin signaling reduce the lesion site-specific changes in granule cell migration, indicating that galanin plays a role in such deficits in neuronal cell migration. The present study suggests that manipulating galanin signaling may be a potential therapeutic target for acutely injured brains during development.SIGNIFICANCE STATEMENT Deficits in neuronal cell migration caused by brain injury result in abnormal development of cortical layers, but the underlying mechanisms remain to be determined. Here, we report that on brain injury, endogenous levels of galanin, a neuropeptide, are altered in a lesion site-specific manner, decreasing at the lesion sites but increasing in the surroundings of lesion sites. The changes in galanin levels positively correlate with the migration rate of immature neurons. Manipulations of galanin signaling ameliorate the effects of injury on neuronal migration and cortical layer development. These results shed a light on galanin as a potential therapeutic target for acutely injured brains during development.


Assuntos
Lesões Encefálicas/metabolismo , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Movimento Celular/fisiologia , Cerebelo/metabolismo , Galanina/metabolismo , Animais , Animais Recém-Nascidos , Lesões Encefálicas/patologia , Células Cultivadas , Cerebelo/lesões , Cerebelo/patologia , Relação Dose-Resposta a Droga , Feminino , Masculino , Camundongos
4.
J Child Neurol ; 36(6): 482-490, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33356784

RESUMO

OBJECTIVE: Acute brain injury is a frequent perinatal neurologic complication that can involve the cerebellum. Although short-term outcomes of infants with neonatal cerebellar injury are well described, neurologic sequelae in older children are underreported. Here, we describe epilepsy-related outcomes in young children who suffered from neonatal cerebellar injuries. METHODS: In-house automated software identified patients with neonatal brain injuries who were evaluated at our institution both as neonates (≤28 days) and as children (≥1 year). Neonatal hospital course, neuroimaging, and outcomes related to epilepsy were reviewed from the medical record. Patients were stratified into 2 groups based on neonatal brain injuries: those with cerebellar injury and those without cerebellar involvement. RESULTS: Of the 282 neonates followed through childhood over the decade-long study period, 33 (12%) experienced neonatal brain injury. All 33 cases involved supratentorial injury, and 5 (15%) also included cerebellar injury. The development of epilepsy was significantly less likely in the group with cerebellar involvement (40%) compared to that with cerebellar sparing (82%; P = 0.043). In some cases, children with cerebellum-sparing injuries required admission for seizure control and developed drug-resistant epilepsy as well as status epilepticus. These outcomes occurred less frequently in the group with cerebellar involvement. CONCLUSIONS: Epilepsy-related sequelae may occur less frequently when the cerebellum is involved in neonatal brain injury. Larger prospective studies are needed to clarify how cerebellocortical networks impact functional brain connectivity and epilepsy longitudinally.


Assuntos
Lesões Encefálicas/complicações , Epilepsia/complicações , Cerebelo/diagnóstico por imagem , Cerebelo/lesões , Feminino , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética/métodos , Masculino , Neuroimagem/métodos , Estudos Retrospectivos
5.
Neurosurg Rev ; 44(1): 351-361, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31758338

RESUMO

This study aimed to compare the surgical outcomes and morbidities of retrosigmoid and translabyrinthine approaches for large vestibular schwannoma (VS), with a focus on cerebellar injury and morbidities. Eighty-six consecutive patients with large VS, with a maximal extrameatal diameter > 3.0 cm, were reviewed between August 2010 and September 2018. The surgical outcomes, operating time, volume change of perioperative cerebellar edema, and inpatient rehabilitation related to cerebellar morbidities were compared between the two approaches. In total, 53 and 33 patients underwent the retrosigmoid and translabyrinthine approaches, respectively. The median follow-up time was 34.5 months. Surgical outcomes, including the extent of resection, tumor recurrence, and facial nerve preservation, showed no significant differences between the two groups. Patients who underwent the retrosigmoid approach showed a marginal trend for postoperative lower cranial nerve (LCN) dysfunction (P = 0.068). Although the approaching procedure time was longer in the translabyrinthine group, the tumor resection time was significantly longer in the retrosigmoid group (P = 0.001). The median change in the volume of the perioperative cerebellar edema was significantly larger in the retrosigmoid group (P < 0.001) and significantly related to the retrosigmoid approach, solid VS, and tumor resection time. Most cerebellar and LCN deficits were transient; however, the patients in the retrosigmoid group underwent inpatient rehabilitation more than those in the translabyrinthine group (P = 0.018). Both surgical approaches show equivalent surgical outcomes. Notably, the translabyrinthine approach for large VS has advantages in that it reduces cerebellar injury and related morbidities.


Assuntos
Cerebelo/lesões , Orelha Interna/cirurgia , Recidiva Local de Neoplasia/cirurgia , Neuroma Acústico/cirurgia , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias/etiologia , Adulto , Cerebelo/diagnóstico por imagem , Orelha Interna/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Recidiva Local de Neoplasia/diagnóstico por imagem , Neuroma Acústico/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Estudos Retrospectivos
6.
Medicine (Baltimore) ; 100(48): e28024, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-35049215

RESUMO

INTRODUCTION: The cortico-ponto-cerebellar tract (CPCT) is involved in coordination of movement; injury of the CPCT can therefore be accompanied by ataxia. In this study, using diffusion tensor tractography (DTT), we investigated injury of the CPCT in patients with mild traumatic brain injury (TBI). METHODS: We recruited 45 consecutive patients with ataxia following mild TBI and 20 normal control subjects. The score of assessment and rating of ataxia (SARA) was used to evaluate of ataxia. The patients were classified into 2 groups based on the SARA; patient group A had with post-traumatic ataxia and patient group B had without post-traumatic ataxia. The fractional anisotropy (FA) value and fiber number (FN) of the CPCT was measured. RESULTS: Significant differences were observed in the FA and FN values of the CPCT between patient group A and the control group and between patient groups A and B (P < .05). In addition, a significant difference was observed in the FA value only of the CPCT between patient group B and the control group (P < .05). However, no significant difference was observed in the FN value of the CPCT between patient group B and the control group (P > .05). CONCLUSION: By using DTT, injury of the CPCT was demonstrated in patients who showed ataxia following mild TBI. These results suggest that DTT would be useful for evaluation of the CPCT in patients with ataxia after mTBI because mTBI usually does not show any abnormalities on conventional brain MRI.


Assuntos
Ataxia/etiologia , Concussão Encefálica/complicações , Cerebelo/lesões , Adulto , Idoso , Concussão Encefálica/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
J Neurosci Res ; 99(2): 446-454, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33089563

RESUMO

Soccer, as a contact sport, exposes players to repetitive head impacts, especially through heading the ball. The question of a long-term brain cumulative effect remains. Our objective was to determine whether exposure to head impacts over one soccer season was associated with changes in functional brain connectivity at rest, using magnetic resonance imaging (MRI). In this prospective cohort study, 10 semi-professional men soccer players, aged 18-25 years, and 20 age-matched men athletes without a concussion history and who do not practice any contact sport were recruited in Bordeaux (France). Exposure to head impacts per soccer player during competitive games over one season was measured using video analysis. Resting-state functional magnetic resonance imaging data were acquired for both groups at two times, before and after the season. With a seed-based analysis, resting-state networks that have been intimately associated with aspects of cognitive functioning were investigated. The results showed a mean head impacts of 42 (±33) per soccer player over the season, mainly intentional head-to-ball impacts and no concussion. No head impact was found among the other athletes. The number of head impacts between the two MRI acquisitions before and after the season was associated with increased connectivity within the default mode network and the cortico-cerebellar network. In conclusion, our findings suggest that the brain functioning changes over one soccer season in association with exposure to repetitive head impacts.


Assuntos
Lesões Encefálicas Traumáticas/patologia , Conectoma , Rede de Modo Padrão/diagnóstico por imagem , Traumatismos Cranianos Fechados/complicações , Futebol/lesões , Adolescente , Adulto , Concussão Encefálica/diagnóstico por imagem , Concussão Encefálica/etiologia , Concussão Encefálica/patologia , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/etiologia , Cerebelo/diagnóstico por imagem , Cerebelo/lesões , Cerebelo/patologia , França , Traumatismos Cranianos Fechados/epidemiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Recidiva , Descanso , Adulto Jovem
8.
Radiología (Madr., Ed. impr.) ; 62(4): 298-305, jul.-ago. 2020. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-194247

RESUMO

OBJETIVOS: Describir los patrones normales de activación en el cerebelo de funciones específicas cerebrales (motor, lenguaje, memoria) y su relación topográfica en la corteza cerebelosa utilizando resonancia magnética funcional. MATERIALES Y MÉTODOS: Se evaluaron 25 sujetos sanos, 8 mujeres y 17 hombres de entre 16 y 64 años, 23 diestros y 2 zurdos, mediante resonancia magnética funcional basada en tareas de lenguaje, memoria, motor y visual, en equipo de resonancia de 1.5 Teslas. RESULTADOS: Se caracterizó la actividad funcional en el cerebelo asociada a los componentes motores, de lenguaje y memoria, describiendo la relación con las regiones topográficas, así como su relación funcional con áreas corticales cerebrales. CONCLUSIONES: El conocimiento sobre los patrones de normalidad de las características morfológicas y del comportamiento funcional en el cerebelo, así como su relación con el cerebro, es importante para el radiólogo y médico clínico en la evaluación del cerebelo y sus posibles condiciones patológicas


OBJECTIVES: To describe the normal patterns of cerebellar activation in specific cerebral functions (motor, language, memory) and their topographical correlations in the cerebellar cortex on functional magnetic resonance imaging. MATERIALS AND METHODS: We evaluated 25 healthy subjects (8 women and 17 men; 23 right-handed and 2 left-handed; age range, 16-64 years), who did language, memory, and motor tasks while undergoing 1.5T functional magnetic resonance imaging. RESULTS: We assessed functional activity of the cerebellum associated with motor, language, and memory components, describing their relations with topographical regions of the cerebellum and their functional relations with areas in the cerebral cortex. CONCLUSIONS: Knowledge of the normal patterns of morphological characteristics and functional behavior in the cerebellum as well as their relations with the brain is important for radiologists and clinicians evaluating the cerebellum and possible pathological conditions that affect it


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Cerebelo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Fala/fisiologia , Memória/fisiologia , Neuroimagem Funcional , Lateralidade Funcional , Cerebelo/lesões
9.
AJNR Am J Neuroradiol ; 41(8): E61, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32586961
10.
Rev. bras. neurol ; 55(3): 33-37, jul.-set. 2019. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1022916

RESUMO

Luigi Luciani (1840-1919) was an illustrious Italian citizen and physiologist whose research scope covered mainly cardiovascular subjects, the nervous system, and fasting. He published in 1891 a modern landmark of the study of cerebellar physiology - "Il cervelletto: nuovistudi di normal and pathología physiology" / "The cerebellum: new studies on normal and pathological physiology." In his experiment, a dog survived after cerebellectomy, reporting a triad of symptoms (asthenia, atonia, and astasia). In this way, the eminent neurophysiologist improved the operative technique and sterile processes to redirect the issue of cerebellar symptoms. Luciani died at age 78, a hundred years ago, and left mainly the understanding of the role of the cerebellum in regulating postural tone and muscle strength, which represented a step forward in understanding cerebellar motor physiology. In recent decades, cognitive / affective function has been added to the cerebellar motor, and there has also been a better understanding of cerebellar circuits.


Luigi Luciani (1840-1919) foi um ilustre cidadão e fisiologista italiano, cujo escopo de pesquisa abrangia principalmente assuntos cardiovasculares, sistema nervoso e jejum. Ele publicou em 1891 um marco moderno do estudo da fisiologia do cerebelo - "Il cervelletto: nuovistudi di fisiologia normale and patologica" / "O cerebelo: novos estudos sobre fisiologia normal e patológica". Em seu experimento, um cão sobreviveu após a cerebelectomia, com o relatório de uma tríade de sintomas (astenia, atonia e astasia). Dessa maneira, o eminente neurofisiologista aprimorou a técnica operatória e os processos estéreis para redirecionar a questão dos sintomas cerebelares. Luciani morreu aos 78 anos, cem anos atrás, e deixou principalmente a compreensão do papel do cerebelo na regulação do tônus postural e da força muscular, o que representou um passo adiante na compreensão da fisiologia motora cerebelar. Nas últimas décadas, a função cognitivo / afetiva foi adicionada à motora cerebelar e, também, houve uma melhor compreensão dos circuitos do cerebelo.


Assuntos
Humanos , História do Século XIX , História do Século XX , Neurociências/história , Cerebelo/fisiologia , Neurofisiologia/história , Cerebelo/lesões , Itália
11.
Dev Biol ; 455(2): 458-472, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31376393

RESUMO

The cerebellum undergoes major rapid growth during the third trimester and early neonatal stage in humans, making it vulnerable to injuries in pre-term babies. Experiments in mice have revealed a remarkable ability of the neonatal cerebellum to recover from injuries around birth. In particular, recovery following irradiation-induced ablation of granule cell precursors (GCPs) involves adaptive reprogramming of Nestin-expressing glial progenitors (NEPs). Sonic hedgehog signaling is required for the initial step in NEP reprogramming; however, the full spectrum of developmental signaling pathways that promote NEP-driven regeneration is not known. Since the growth regulatory Hippo pathway has been implicated in the repair of several tissue types, we tested whether Hippo signaling is involved in regeneration of the cerebellum. Using mouse models, we found that the Hippo pathway transcriptional co-activator YAP1 (Yes-associated protein 1) but not TAZ (transcriptional coactivator with PDZ binding motif, or WWTR1) is required in NEPs for full recovery of cerebellar growth following irradiation one day after birth. Although Yap1 plays only a minor role during normal development in differentiation of NEPs or GCPs, the size of the cerebellum, and in particular the internal granule cell layer produced by GCPs, is significantly reduced in Yap1 mutants after irradiation, and the organization of Purkinje cells and Bergmann glial fibers is disrupted. The initial proliferative response of Yap1 mutant NEPs to irradiation is normal and the cells migrate to the GCP niche, but subsequently there is increased cell death of GCPs and altered migration of granule cells, possibly due to defects in Bergmann glia. Moreover, loss of Taz along with Yap1 in NEPs does not abrogate regeneration or alter development of the cerebellum. Our study provides new insights into the molecular signaling underlying postnatal cerebellar development and regeneration.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Proteínas de Ciclo Celular/fisiologia , Cerebelo/citologia , Células-Tronco Neurais/fisiologia , Aciltransferases , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Encéfalo/efeitos da radiação , Lesões Encefálicas , Regeneração do Cérebro/fisiologia , Proteínas de Ciclo Celular/genética , Morte Celular , Movimento Celular , Cerebelo/crescimento & desenvolvimento , Cerebelo/lesões , Deleção de Genes , Camundongos , Nestina , Neuroglia/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP
12.
Nat Commun ; 10(1): 3128, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311934

RESUMO

To select actions based on sensory evidence, animals must create and manipulate representations of stimulus information in memory. Here we report that during accumulation of somatosensory evidence, optogenetic manipulation of cerebellar Purkinje cells reduces the accuracy of subsequent memory-guided decisions and causes mice to downweight prior information. Behavioral deficits are consistent with the addition of noise and leak to the evidence accumulation process. We conclude that the cerebellum can influence the accurate maintenance of working memory.


Assuntos
Cerebelo/fisiologia , Tomada de Decisões/fisiologia , Memória de Curto Prazo/fisiologia , Animais , Comportamento Animal/fisiologia , Cerebelo/citologia , Cerebelo/lesões , Craniotomia , Feminino , Masculino , Camundongos , Modelos Animais , Optogenética , Estimulação Luminosa , Células de Purkinje/fisiologia
13.
Eur J Paediatr Neurol ; 23(4): 604-608, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31147107

RESUMO

Pediatric abusive head trauma (AHT) or non accidental head trauma (NAHT) is a major cause of death from trauma in children under 2 years of age. Main etiological factor for non accidental head trauma is shaking a baby, causing brain injury by rotational head acceleration and deceleration. The consequent brain damage as shown by magnetic resonance imaging (MRI) is subdural haemorrhage and to a lesser extent parenchymal injuries of variable severity. Involvement of the cerebellum has very rarely been described. We report the clinical history and the development of cerebral magnetic resonance imaging findings in two children with serious brain injury following probable shaking who presented the typical "triad" with subdural haematoma, retinal haemorrhage and encephalopathy. We want to draw attention to cerebellar involvement characterized by cortico-subcortical signal alterations most prominent on T2w images following diffusion changes during the acute period. We discuss cerebellar involvement as a sign of higher severity of AHT which is probably underrecognized.


Assuntos
Lesões Encefálicas/patologia , Cerebelo/lesões , Cerebelo/patologia , Maus-Tratos Infantis , Traumatismos Craniocerebrais/patologia , Lesões Encefálicas/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Maus-Tratos Infantis/diagnóstico , Traumatismos Craniocerebrais/diagnóstico por imagem , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética/métodos , Masculino
14.
Neurochem Res ; 44(2): 374-387, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30460640

RESUMO

VGF nerve growth factor inducible (VGF) is a neuropeptide precursor induced by brain-derived neurotrophic factor and nerve growth factor. VGF is increased in the prefrontal cortex and cerebrospinal fluid in schizophrenia patients. In our previous study, VGF-overexpressing mice exhibited schizophrenia-like behaviors and smaller brain weights. Brain developmental abnormality is one cause of mental illness. Research on brain development is important for discovery of pathogenesis of mental disorders. In the present study, we investigated the role of VGF on cerebellar development. We performed a histological analysis with cerebellar sections of adult and postnatal day 3 mice by Nissl staining. To investigate cerebellar development, we performed immunostaining with antibodies of immature and mature granule cell markers. To understand the mechanism underlying these histological changes, we examined MAPK, Wnt, and sonic hedgehog signaling by Western blot. Finally, we performed rotarod and footprint tests using adult mice to investigate motor function. VGF-overexpressing adult mice exhibited smaller cerebellar sagittal section area. In postnatal day 3 mice, a cerebellar sagittal section area reduction of the whole cerebellum and external granule layer and a decrease in the number of mature granule cells were found in VGF-overexpressing mice. Additionally, the number of proliferative granule cell precursors was lower in VGF-overexpressing mice. Phosphorylation of Trk and Erk1 were increased in the cerebellum of postnatal day 3 VGF-overexpressing mice. Adult VGF-overexpressing mice exhibited motor disability. All together, these findings implicate VGF in the development of cerebellar granule cells via promoting MAPK signaling and motor function in the adult stage.


Assuntos
Cerebelo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/imunologia , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Células de Purkinje/metabolismo , Animais , Encéfalo/metabolismo , Proliferação de Células/fisiologia , Cerebelo/lesões , Camundongos , Fatores de Crescimento Neural
15.
Medicina (B Aires) ; 78(5): 364-367, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-30285930

RESUMO

We present two cases of lateral medullary stroke in subjects with extracranial trajectory of the postero-inferior cerebellar artery. Case 1: a 21-year-old male who presented ataxia and right dysmetria after cervical trauma in a rugby match. Case 2: 56-year-old woman, who started with vertigo and left hemiparesis after intense physical effort. In both cases, the angiographic studies showed an extracranial trajectory of the posterior inferior cerebellar artery. This vessel rarely originates below the foramen magnum, in close relationship with the first three cervical vertebrae and the atlanto-axial joint. At this level, it is exposed to mechanical damage causing dissection, such as direct trauma, abrupt cervical manipulation or prolonged cephalic extension. Therefore, this association should be considered in patients with stroke of the lateral region of the bulb and extracranial trajectory of the posterior-inferior cerebellar artery.


Assuntos
Dissecção Aórtica/complicações , Cerebelo/irrigação sanguínea , Síndrome Medular Lateral/etiologia , Artéria Cerebral Posterior/lesões , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/lesões , Cerebelo/patologia , Angiografia Cerebral/métodos , Feminino , Humanos , Síndrome Medular Lateral/diagnóstico por imagem , Síndrome Medular Lateral/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Posterior/diagnóstico por imagem , Artéria Cerebral Posterior/patologia , Adulto Jovem
16.
Sleep Med ; 52: 134-137, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30321820

RESUMO

BACKGROUND: REM sleep (REMS) is considered vital for supporting well-being and normal cognition. However, it remains unclear if and how decreases in REMS impair cognitive abilities. Rare case studies of patients with REMS abolishment due to pontine lesions remain sporadic, and formal evaluation of cognitive status is lacking. In 1984, Lavie and colleagues described the case of Y.C. - a man with a pontine lesion and near-total absence of REMS who led a normal life. Here, we set out to re-evaluate this individual's REMS status 30 years after the original report, and formally assess his cognitive abilities. METHODS: Four whole-night polysomnographic sleep recordings were conducted to evaluate sleep architecture. Sleep scoring was performed according to the American Academy of Sleep Medicine (AASM) guidelines. Cranial Computed Tomography (CT) imaging was performed, as well as formal neuropsychological testing to evaluate cognitive functions. RESULTS: Y.C. averaged 4.5% of sleep time in REMS, corresponding to the 0.055 percentile of normal values for his age. Furthermore, residual REMS episodes were short and only occurred towards the end of the night. CT imaging revealed damage and metallic fragments in pons, cerebellum, and thalamus. Neuropsychological evaluation demonstrated average to high-average cognitive skills, normal memory, and motor difficulties including speech and left hand dyspraxia. CONCLUSIONS: To our knowledge, this is the only case where REMS loss resulting from pontine lesion was re-evaluated after many years. We find a near-total absence of REMS with no signs of significant compensation throughout adult life, along with normal cognitive status. The results provide a unique perspective on the ongoing debate regarding the functional role of REMS in supporting cognition.


Assuntos
Cognição/fisiologia , Testes Neuropsicológicos/estatística & dados numéricos , Ponte/lesões , Sono REM/fisiologia , Cerebelo/lesões , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia/métodos , Tomografia Computadorizada por Raios X/métodos
17.
Medicina (B.Aires) ; 78(5): 364-367, oct. 2018. ilus
Artigo em Espanhol | LILACS | ID: biblio-976126

RESUMO

Presentamos dos casos de accidente cerebrovascular en sujetos con trayecto extracraneal de la arteria cerebeloso póstero-inferior. Caso 1: varón de 21 años, quien presentó ataxia y dismetría derecha luego de un traumatismo cervical en un partido de rugby. Caso 2: mujer de 56 años, quien inició con vértigo y hemiparesia izquierda luego de esfuerzo físico intenso. En ambos casos, los estudios angiográficos mostraron un trayecto extracraneal de la arteria cerebelosa póstero-inferior. Este vaso raramente se origina por debajo del foramen magno, en relación cercana con las primeras tres vértebras cervicales y la articulación atlanto-axial. En este nivel, está expuesta a daño mecánico causante de disección, como por ejemplo trauma directo, manipulación cervical abrupta o extensión cefálica prolongada. Por lo tanto, en pacientes con accidente cerebrovascular de región lateral de bulbo y trayecto extracraneal de la arteria cerebelosa póstero-inferior se debería considerar esta asociación.


We present two cases of lateral medullary stroke in subjects with extracranial trajectory of the postero-inferior cerebellar artery. Case 1: a 21-year-old male who presented ataxia and right dysmetria after cervical trauma in a rugby match. Case 2: 56-year-old woman, who started with vertigo and left hemiparesis after intense physical effort. In both cases, the angiographic studies showed an extracranial trajectory of the posterior inferior cerebellar artery. This vessel rarely originates below the foramen magnum, in close relationship with the first three cervical vertebrae and the atlanto-axial joint. At this level, it is exposed to mechanical damage causing dissection, such as direct trauma, abrupt cervical manipulation or prolonged cephalic extension. Therefore, this association should be considered in patients with stroke of the lateral region of the bulb and extracranial trajectory of the posterior-inferior cerebellar artery.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Síndrome Medular Lateral/etiologia , Cerebelo/irrigação sanguínea , Artéria Cerebral Posterior/lesões , Dissecção Aórtica/complicações , Síndrome Medular Lateral/patologia , Síndrome Medular Lateral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Angiografia Cerebral/métodos , Cerebelo/lesões , Cerebelo/patologia , Cerebelo/diagnóstico por imagem , Artéria Cerebral Posterior/patologia , Artéria Cerebral Posterior/diagnóstico por imagem , Dissecção Aórtica/patologia , Dissecção Aórtica/diagnóstico por imagem
18.
Elife ; 72018 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-30091706

RESUMO

Outside of the neurogenic niches of the brain, postmitotic neurons have not been found to undergo efficient regeneration. We demonstrate that mouse Purkinje cells (PCs), which are born at midgestation and are crucial for development and function of cerebellar circuits, are rapidly and fully regenerated following their ablation at birth. New PCs are produced from immature FOXP2+ Purkinje cell precursors (iPCs) that are able to enter the cell cycle and support normal cerebellum development. The number of iPCs and their regenerative capacity, however, diminish soon after birth and consequently PCs are poorly replenished when ablated at postnatal day five. Nevertheless, the PC-depleted cerebella reach a normal size by increasing cell size, but scaling of neuron types is disrupted and cerebellar function is impaired. Our findings provide a new paradigm in the field of neuron regeneration by identifying a population of immature neurons that buffers against perinatal brain injury in a stage-dependent process.


Assuntos
Proliferação de Células , Cerebelo/crescimento & desenvolvimento , Cerebelo/lesões , Células de Purkinje/fisiologia , Regeneração , Células-Tronco/fisiologia , Fatores Etários , Animais , Camundongos
19.
Brain Dev ; 40(9): 743-752, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29776704

RESUMO

PURPOSE: Cerebellar injury is well established as an important finding in preterm infants with cerebral palsy (CP). In this study, we investigated associations between injury to the cerebellar peduncles and motor impairments in preterm infants using quantitative tractography at term-equivalent age, which represents an early phase before the onset of motor impairments. METHODS: We studied 64 preterm infants who were born at <33 weeks gestational age. These infants were divided into three groups: CP, Non-CP (defined as infants with periventricular leukomalacia but having normal motor function), and a Normal group. Diffusion tensor imaging was performed at term-equivalent age and motor function was assessed no earlier than a corrected age of 2 years. Using tractography, we measured fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of the superior cerebellar peduncles (SCP) and middle cerebellar peduncles (MCP), as well as the motor/sensory tracts. RESULTS: The infants in the CP group had significantly lower FA of the SCP and sensory tract than those in the other groups. There was no significant difference in FA and ADC of the motor tract among the three groups. Severity of CP had a significant correlation with FA of the MCP, but not with the FA of other white matter tracts. CONCLUSION: Our results suggested that the infants with CP had injuries of the ascending tracts (e.g. the SCP and sensory tract), and that additional MCP injury might increase the severity of CP. Quantitative tractography assessment at term-equivalent age may be useful for screening preterm infants for prediction of future motor impairments.


Assuntos
Cerebelo/diagnóstico por imagem , Cerebelo/lesões , Recém-Nascido Prematuro , Transtornos dos Movimentos/diagnóstico por imagem , Paralisia Cerebral/diagnóstico por imagem , Imagem de Tensor de Difusão , Feminino , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Prognóstico
20.
Pediatr Res ; 83(5): 1004-1010, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29360805

RESUMO

BackgroundPreterm birth is associated with an increased risk of cerebellar injury. The aim of this study was to assess the impact of cerebellar hemorrhages (CBH) on cerebral white matter microstructural tissue organization and cerebellar volume at term-equivalent age (TEA) in extremely preterm infants. Furthermore, we aimed to evaluate the association between CBH and neurodevelopmental outcome in late infancy.MethodsA total of 24 preterm infants with punctate CBH were included and each matched to two preterm control infants. T1-, T2-weighted images and diffusion-weighted imaging were acquired on a 3T magnetic resonance imaging (MRI) system. Regions of interest were drawn on a population-specific neonatal template and automatically registered to individual fractional anisotropy (FA) maps. Brain volumes were automatically computed. Neurodevelopmental outcome was assessed using the Bayley scales of Infant and Toddler Development at 2 years of corrected age.ResultsCBHs were not significantly related to FA in the posterior limb of the internal capsule and corpus callosum or to cerebellar volume. Infants with CBH did not have poorer neurodevelopmental outcome compared with control infants.ConclusionThese findings suggest that the impact of mild CBH on early macroscale brain development may be limited. Future studies are needed to assess the effects of CBH on long-term neurodevelopment.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Cerebelo/lesões , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Anisotropia , Estudos de Casos e Controles , Pré-Escolar , Estudos de Coortes , Imagem de Difusão por Ressonância Magnética , Feminino , Idade Gestacional , Humanos , Processamento de Imagem Assistida por Computador/métodos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Imageamento por Ressonância Magnética , Masculino , Transtornos do Neurodesenvolvimento , Reconhecimento Automatizado de Padrão , Risco
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