Avaliação por ressonância magnética funcional e estimulação magnética transcraniana da intervenção única da terapia espelho em pacientes após acidente vascular cerebral isquêmico

Mirror therapy (MT) is being used as a rehabilitation tool in various diseases, including stroke. Although some studies have shown its effectiveness, little is known about neural mechanisms that underlie the rehabilitation process. Therefore, this study aimed at assessing cortical neuromodulation after a single MT intervention in ischemic stroke survivors, by means of by functional Magnetic Resonance Imaging (fMRI) and Transcranial Magnetic Stimulation (TMS). Fifteen patients participated in a single thirty minutes MT session. fMRI data was analyzed bilaterally in the following Regions of Interest (ROI): Supplementary Motor Area (SMA), Premotor cortex (PMC), Primary Motor cortex (M1), Primary Sensory cortex (S1) and Cerebellum. In each ROI, changes in the percentage of occupation and beta values were computed. Group fMRI data showed a significant decreased in the percentage of occupation in PMC and cerebellum, contralateral to the affected hand (p <0.05). Significant increase in beta values was observed in the following contralateral motor areas: SMA, Cerebellum, PMC and M1 (p<0,005). Moreover, a significant decrease was observed in the following ipsilateral motor areas: PMC and M1 (p <0,001). In S1 a bilateral significant decrease (p<0.0005) was observed.TMS consisted of the analysis of Motor Evoked Potential (MEP) of M1 hotspot. A significant increase in the amplitude of the MEP was observed after therapy in the group (p<0,0001) and individually in 4 patients (p <0.05). Altogether, our results imply that single MT intervention is already capable of promoting changes in neurobiological markers toward patterns observed in healthy subjects. Furthermore, the contralateral hemisphere motor areas changes are opposite to the ones in the ipsilateral side, suggesting an increase system homeostasis.

Efeitos da eliminação de neurônios infragranulares sobre a especificação de neurônios supragranulares do córtex cerebral

The cerebral cortex of mammals is histologically organized into different layers of excitatory neurons that have distinct patterns of connections with cortical or subcortical targets. During development, these cortical layers are established through an intricate combination of neuronal specification and migration in a radial pattern known as "insideout": deep-layer neurons are generated prior to upper-layer neurons. In the last few decades, several genes encoding transcription factors involved in the sequential specification of neurons destined to different cortical layers have been identified. However, the influence of early-generated neurons in the specification of subsequent neuronal cohorts remains unclear. To investigate this possible influence, we induced the selective death of cortical neurons from layer V and VI before the generation of layer II, III and IV neurons. Thus, we can evaluate the effects of ablation of early born neurons on the phenotype of late born neurons. Our data shows that one-day after ablation, layer VI neurons expressing the transcription factor TBR1 are newly generated while virtually no neuron expressing TBR1 was generated in the same age in control animals. This suggests that progenitors involved in the generation of neurons destined for superficial layers suffer interference from the selective death of neurons in deep layers, changing their specification. We also observed that while TBR1-positive neurons are located exclusively in deep cortical layers of control animals, many TBR1-positive neurons are misplaced in superficial layers of ablated animals, suggesting that the migration of cortical neurons could be controlled independently of neuronal phenotypes. Furthermore, we observed an increase in layer V neurons expressing CTIP2 and neurons expressing SATB2 and that these cells have changed their distributions. As a conclusion, our data indicate the existence of a mechanism of control exercised by the early-generated neurons in the cerebral cortex on the fate of the progenitors involved in the generation of the following cortical neurons. This mechanism could help to control the number of neurons in different layers and contribute to the establishment of different cortical areas

Características sociodemográficas, hábitos de sono, estado cognitivo e funcional após acidente vascular cerebral

ABSTRACT Introduction: The cerebrovascular accident (CVA) is an important cause of neurological impairment. Few data about the factors associated with morbidity of cerebrovascular accident are found in Brazil. Objectives: Evaluate sociodemographic characteristics, sleep habits, cognitive and functional status of patients with cerebrovascular accident. Methods: The patients evaluated through questionnaire Step 1 to survey the sociodemographic characteristics and Modified Rankin Scale for functional assessment. The neurological degree was evaluated by the National Institutes of Health Stroke Scale (NIHSS), the sleep Habits questionnaire for sleep and cognitive status by the Mini-Examination of the Mental State (MEMS). The data were analyzed using the chi-square test to determine differences in proportions of variables and linear regression analysis. Results: 305 patients were evaluated and the larger number of subjects was between 50 and 69 years (40%), most patients had no formal education (40.3%) and had ischemic type of cerebrovascular accident (72.5%). In the analysis of the functionality it was found that most patients had moderate impairment (55.1%). The results of the sleep habits showed that 63,6% of patients had one more person in the bedroom,12,3% complained about too much noise in the 11 room and 35% of too much light. From these patients 5,8% were smokers, 7,8% and 70,1% drank coffee drinkers, 28,6% had difficulty in initiate to sleep and woke up 37,6% in the middle of the night. Were showed complaints about nightmares (11%), feeling of suffocation (37,7%) and 35% felt very sleepy during the day. In addition, 95% were unemployed, 80,5% did not perform physical activities and 95,4% did not perform mental activities. The cognitive screening conducted a determined association of cognitive status with age and education level and neurological status. Conclusion: The study showed a high frequency of cases of cerebrovascular accident with functional dependence in a moderate degree, identified that many patients do not follow hygienic measures of sleep and found that the assessment of cognitive deficits must take into consideration the age, educational level and degree of neurological patients. We suggest the need for programs of assistance to victims of cerebrovascular accident patients, with a multidimensional approach including the rehabilitation team, the role of sleep medicine and Neuropsychology, so that patients have access to a more appropriate functional rehabilitation, develop a lifestyle that ensures a good sleep quality and are evaluated and rehabilitated with regard to cognitive impairment

Qualidade subjetiva do sono e queixa de insônia em pacientes com Acidente Vascular Cerebral

Brain injury can be associated with changes in the sleep-wake cycle. However, studies about sleep disturbances and their relationship with quality of sleep are scarce. Besides, it remains to be known how stroke affects the mechanisms of sleep. The aim of this study was to investigate quality of sleep, complaints of sleep disturbances and associated factors in stroke patients from the Physical Therapy services in Natal -RN. This was a cross-sectional descriptive study involving 70 individuals (aged 45-65 years), 40 patients (57 ± 7 years), 11 ± 9 months after injury, and 30 healthy individua ls (52 ± 6 years), evaluated with the Pittsburgh Sleep Quality Index (PSQI) and Sleep Habits Questionnaire. The data were analyzed by Chi-square test, t Student test and logistic regression. Poor quality sleep was found in 57,5% of the patients (6,3 ± 3,5) and was significantly higher than in the control population (3,9 ± 2,2) (t Student test, p=0,002). The patients showed significantly higher value of PSQI than controls: sleep latency (p=0,019), length of sleep (p=0,039) and dysfunction during the day (p=0,001). Regarding complaints of sleep disturbances (dyssomnias and parasomnias) analyzed by Chi-square test, the complaint of insomnia was the most prevalent (patients: 37,5%; healthy subjects: 6,7%; p=0,007). Regression analysis showed that sl eep latency (p=0,036) and complaint of insomnia (p=0,036) were associated with quality sleep. In addition, female gender (p=0,036) and complaint of broken sleep (p=0,003) were considered risk factors for the presence of insomnia. Our results show that stroke affects the homeostatic process of sleep. Shorter sleep latency and the absence of insomnia are considered protective factors for good sleep quality and this should be taken into consideration in the diagnostic and therapeutic strategies

Proposta de Intervenção para Auxiliar a Reabilitação Motora e Cognitiva de Pacientes com Acidente Vascular Cerebral

Stroke is the leading cause of combined motor and cognitive disability worldwide. The rehabilitation of stroke patients is mostly directed towards motor recovery through the training of the affected member under supervision of a Physical Therapist. In the present study we introduce a new approach for both cognitive and motor therapy, which relies on motor imagery of the upper limbs and working memory training. This therapy should be utilized as an adjuvant to physical therapy. Ten individuals (5 men and 5 women) were selected for the pilot study, all of them in the acute phase of the first ischemic stroke episode. The control group had 5 individuals who were submitted to physical therapy only, whilst the other 5 patients in the experimental group also performed the cognitive and motor training with a video game specially built for this study. Two patients left the experimental group before the end. Total training lasted for 9 weeks, 2 times a week, for half an hour. Patients reported they enjoyed playing the game, even though it required a lot of mental effort, according to them. Plus, they considered it had a beneficial influence in their activities of daily living. No side effects were reported. Preliminary results suggest there is a difference between groups in cognitive and upper limb motor evaluation following the intervention. It is important to notice that our conclusions are limited due the small sample number. Overall, this work is supported by other studies in literature focused in rehabilitation with motor imagery and working memory and indicate a continuity of the research, increasing total training hours