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Neurodegenerative diseases are a broad heterogeneous group affecting the nervous system. They are characterized, from a pathophysiological perspective, by the selective involvement of a subpopulation of nerve cells with a consequent clinical picture of a disease. Clinical diagnoses of neurodegenerative diseases are quite challenging and often not completely accurate because of their marked heterogeneity and frequently overlapping clinical pictures. Efforts are being made to define sufficiently specific and sensitive markers for individual neurodegenerative diseases or groups of diseases in order to increase the accuracy and speed of clinical diagnosis. Thus said, this present research aimed to identify biomarkers in the cerebrospinal fluid (CSF) and serum (α-synuclein [α-syn], tau protein [t-tau], phosphorylated tau protein [p-tau], ß-amyloid [Aß], clusterin, chromogranin A [chromogrA], cystatin C [cyst C], neurofilament heavy chains [NFH], phosphorylated form of neurofilament heavy chains [pNF-H], and ratio of tau protein/amyloid beta [Ind tau/Aß]) that could help in the differential diagnosis and differentiation of the defined groups of α-synucleinopathies and four-repeat (4R-) tauopathies characterized by tau protein isoforms with four microtubule-binding domains. In this study, we analyzed a cohort of 229 patients divided into four groups: (1) Parkinson's disease (PD) + dementia with Lewy bodies (DLB) (n = 82), (2) multiple system atrophy (MSA) (n = 25), (3) progressive supranuclear palsy (PSP) + corticobasal syndrome (CBS) (n = 30), and (4) healthy controls (HC) (n = 92). We also focused on analyzing the biomarkers in relation to each other with the intention of determining whether they are useful in distinguishing among individual proteinopathies. Our results indicate that the proposed set of biomarkers, when evaluated in CSF, is likely to be useful for the differential diagnosis of MSA versus 4RT. However, these biomarkers do not seem to provide any useful diagnostic information when assessed in blood serum.
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The complex phenomenological understanding of dystonia has transcended from the clinics to genetics, imaging and neurophysiology. One way in which electrophysiology will impact into the clinics are cases wherein a dystonic clinical presentation may not be typical or a "forme fruste" of the disorder. Indeed, the physiological imprints of dystonia are present regardless of its clinical manifestation. Underpinnings in the understanding of dystonia span from the peripheral, segmental and suprasegmental levels to the cortex, and various electrophysiological tests have been applied in the course of time to elucidate the origin of dystonia pathophysiology. While loss of inhibition remains to be the key finding in this regard, intricacies and variabilities exist, thus leading to a notion that perhaps dystonia should best be gleaned as network disorder. Interestingly, the complex process has now spanned towards the understanding in terms of networks related to the cerebellar circuitry and the neuroplasticity. What is evolving towards a better and cohesive view will be neurophysiology attributes combined with structural dynamic imaging. Such a sound approach will significantly lead to better therapeutic modalities in the future.
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Distonia , Distúrbios Distônicos , Cerebelo , Córtex Cerebral , Humanos , NeurofisiologiaRESUMO
BACKGROUND AND PURPOSE: Non-myelopathic degenerative cervical spinal cord compression (NMDC) frequently occurs throughout aging and may progress to potentially irreversible degenerative cervical myelopathy (DCM). Whereas standard clinical magnetic resonance imaging (MRI) and electrophysiological measures assess compression severity and neurological dysfunction, respectively, underlying microstructural deficits still have to be established in NMDC and DCM patients. The study aims to establish tract-specific diffusion MRI markers of electrophysiological deficits to predict the progression of asymptomatic NMDC to symptomatic DCM. METHODS: High-resolution 3 T diffusion MRI was acquired for 103 NMDC and 21 DCM patients compared to 60 healthy controls to reveal diffusion alterations and relationships between tract-specific diffusion metrics and corresponding electrophysiological measures and compression severity. Relationship between the degree of DCM disability, assessed by the modified Japanese Orthopaedic Association scale, and tract-specific microstructural changes in DCM patients was also explored. RESULTS: The study identified diffusion-derived abnormalities in the gray matter, dorsal and lateral tracts congruent with trans-synaptic degeneration and demyelination in chronic degenerative spinal cord compression with more profound alterations in DCM than NMDC. Diffusion metrics were affected in the C3-6 area as well as above the compression level at C3 with more profound rostral deficits in DCM than NMDC. Alterations in lateral motor and dorsal sensory tracts correlated with motor and sensory evoked potentials, respectively, whereas electromyography outcomes corresponded with gray matter microstructure. DCM disability corresponded with microstructure alteration in lateral columns. CONCLUSIONS: Outcomes imply the necessity of high-resolution tract-specific diffusion MRI for monitoring degenerative spinal pathology in longitudinal studies.
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Compressão da Medula Espinal , Doenças da Medula Espinal , Vértebras Cervicais/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética , Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/diagnóstico por imagemRESUMO
Urban hydrology was created in order to improve methods of managing the runoff of precipitation in towns and protect them from flooding while also protecting public health and environment. The essence of a future solution consists in finding an acceptable compromise of an alternative solution for draining rainwater from a territory. The content of this work is a study focused on resolving the percolation of water from surface runoff and the confrontation between a field test, laboratory analysis, and numerical analysis. By confronting and subsequently proposing conditions for percolation, documents will be created for making urban drainage better and more efficient. The reason for the origin of the subject work follows from the insufficient information on infiltration systems in Slovak technical standards and, likewise, the lack of support for the percolation of water from surface runoff. This work points out the approaches, principles, and fundamentals of a proposal for percolation. The aim of the work is distribution of scientific knowledge in the field of research and solutions for the percolation of water from surface runoff, with emphasis placed on the retention capacity of the selected territory and the intensity of precipitation. A geological study (orientational, detailed or supplementary) must always be conducted with any decision on rainwater percolation in a certain locality. Its range is dependent on the difficulty and type of construction. The preliminary study of areal condition should be focused on detailed engineering-geological and hydrological information. After this work, it is concluded that the percolation of rainwater in urban areas with suitable hydrogeological condition is an effective rainwater management technology as well as protection to congestion of sewer systems.
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Chuva , Cidades , Hidrologia , Eliminação de Resíduos Líquidos , Movimentos da ÁguaRESUMO
Botulinum toxin type A (BoNT) is considered an effective therapeutic option in cervical dystonia (CD). The pathophysiology of CD and other focal dystonias has not yet been fully explained. Results from neurophysiological and imaging studies suggest a significant involvement of the basal ganglia and thalamus, and functional abnormalities in premotor and primary sensorimotor cortical areas are considered a crucial factor in the development of focal dystonias. Twelve BoNT-naïve patients with CD were examined with functional MRI during a skilled hand motor task; the examination was repeated 4 weeks after the first BoNT injection to the dystonic neck muscles. Twelve age- and gender-matched healthy controls were examined using the same functional MRI paradigm without BoNT injection. In BoNT-naïve patients with CD, BoNT treatment was associated with a significant increase of activation in finger movement-induced fMRI activation of several brain areas, especially in the bilateral primary and secondary somatosensory cortex, bilateral superior and inferior parietal lobule, bilateral SMA and premotor cortex, predominantly contralateral primary motor cortex, bilateral anterior cingulate cortex, ipsilateral thalamus, insula, putamen, and in the central part of cerebellum, close to the vermis. The results of the study support observations that the BoNT effect may have a correlate in the central nervous system level, and this effect may not be limited to cortical and subcortical representations of the treated muscles. The results show that abnormalities in sensorimotor activation extend beyond circuits controlling the affected body parts in CD even the first BoNT injection is associated with changes in sensorimotor activation. The differences in activation between patients with CD after treatment and healthy controls at baseline were no longer present.
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Vias Aferentes/diagnóstico por imagem , Toxinas Botulínicas Tipo A/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Fármacos Neuromusculares/uso terapêutico , Córtex Sensório-Motor/diagnóstico por imagem , Torcicolo , Adulto , Vias Aferentes/efeitos dos fármacos , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Desempenho Psicomotor/efeitos dos fármacos , Córtex Sensório-Motor/efeitos dos fármacos , Estatísticas não Paramétricas , Torcicolo/diagnóstico por imagem , Torcicolo/tratamento farmacológico , Torcicolo/fisiopatologiaRESUMO
Electroencephalography (EEG) oscillations reflect the superposition of different cortical sources with potentially different frequencies. Various blind source separation (BSS) approaches have been developed and implemented in order to decompose these oscillations, and a subset of approaches have been developed for decomposition of multi-subject data. Group independent component analysis (Group ICA) is one such approach, revealing spatiospectral maps at the group level with distinct frequency and spatial characteristics. The reproducibility of these distinct maps across subjects and paradigms is relatively unexplored domain, and the topic of the present study. To address this, we conducted separate group ICA decompositions of EEG spatiospectral patterns on data collected during three different paradigms or tasks (resting-state, semantic decision task and visual oddball task). K-means clustering analysis of back-reconstructed individual subject maps demonstrates that fourteen different independent spatiospectral maps are present across the different paradigms/tasks, i.e. they are generally stable.
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Eletroencefalografia/estatística & dados numéricos , Interpretação de Imagem Assistida por Computador/métodos , Algoritmos , Mapeamento Encefálico/métodos , Análise por Conglomerados , Tomada de Decisões/fisiologia , Eletroencefalografia/métodos , Humanos , Imageamento por Ressonância Magnética , Masculino , Análise de Componente Principal , Desempenho Psicomotor/fisiologia , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Percepção Visual/fisiologia , Adulto JovemRESUMO
BACKGROUND: Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction, potentially leading to severe disability. Abnormal cervical spine magnetic resonance imaging (MRI) and motor evoked potentials (MEPs) are independent predictors of disease progression. Abnormal MRI is accompanied by various activation changes in functional brain MRI (fMRI), whereas preoperative and postoperative fMRI adaptations associated with abnormal preoperative MEP remain unknown. METHODS: Twenty patients (9 males, average age 56.6) with evidence of spinal cord compression on MRI and clinical signs of mild CSM were included. Participants were classified according to their preoperative MEP and underwent three brain fMRI examinations: before surgery, 6, and 12 months after surgery while performing repeated extension-flexion of each wrist. RESULTS: Functional MRI activation was compared between two subsets of patients, with normal and clearly abnormal MEP (right wrist: 8 vs. 8; left wrist: 7 vs. 9). At baseline, abnormal MEPs were associated with hyperactivation in the cerebellum. At the first follow-up, further hyperactivations emerged in the contralateral sensorimotor cortices and persisted for 1 year. In normal baseline MEP, activation mostly decreased in the ipsilateral sensorimotor cortex postoperatively. The ipsilateral sensorimotor activation after 1-year follow-up correlated with baseline MEP. CONCLUSIONS: Abnormal corticospinal MEP findings in cervical spondylotic myelopathy were associated with differences in brain activation, which further increased after spinal cord decompression and did not resolve within 12-month follow-up. In summary, surgery may come too late for those patients with abnormal MEP to recover completely despite their mild clinical signs and symptoms.
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Cerebelo/fisiopatologia , Descompressão Cirúrgica/efeitos adversos , Potencial Evocado Motor , Imageamento por Ressonância Magnética , Complicações Pós-Operatórias/fisiopatologia , Compressão da Medula Espinal/cirurgia , Osteofitose Vertebral/cirurgia , Adulto , Idoso , Cerebelo/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Freezing of gait (FOG) is a common disabling symptom of (in) Parkinson's disease (PD). The mechanism of FOG is (in) not clearly understood. We investigated the clinical effect and changes of the activity of the sensorimotor system using repeated functional MRI (fMRI) before and after application of botulinum toxin in Parkinson's disease patients with FOG. METHODS: We investigated 20 patients with PD, 10 with FOG and 10 without FOG. PD patients with FOG were treated with intramuscular application of botulinum toxin type A into the tensor fasciae latae muscle bilaterally. The clinical effect of treatment was assessed using FOG questionnaire, "Time up and go" test, UPDRS, Hoehn and Yahr staging, Clinical global impression scale. Activation of the sensorimotor system was studied using BOLD fMRI of the whole brain during repetitive abduction - adduction of each leg interleaved with rest. The clinical (in the FOG group) and imaging (in both groups) examination was repeated after a four-week interval. RESULTS: In the FOG group, the FOG questionnaire has shown a decline of scores after application of botulinum toxin that suggests possible effect of botulinum toxin on freezing of gait. In fMRI results, both groups manifested reduction of the sensorimotor network activated with leg movement, however, the FOG group also showed increased activation in cerebellar vermis and nuclei, in dorsal pons and in medulla after treatment. CONCLUSION: Alleviation of the FOG in PD patients by botulinum toxin seems to be reflected in the functional participation of the cerebellum and its projections as seen by fMRI.
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Toxinas Botulínicas/uso terapêutico , Transtornos Neurológicos da Marcha/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Marcha , Transtornos Neurológicos da Marcha/etiologia , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologiaRESUMO
Fifty years ago, when the effect of antidepressants on panic disorder was described, a significant progress in understanding this anxiety disorder has been made. Theoretical mechanisms and models of fear and panic disorder were proposed and tested in animal models and humans. With growing possibilities of non-invasive neuroimaging techniques, there is an increasing amount of information on the panic disorder. Unfortunately, a number of circumstances lead to inconsistent findings and its interpretations. In our review, we focused on functional MRI in panic disorder, limitations of current studies, possible interpretations and proposals for future direction. In our opinion, the current findings support the neuroanatomical model of panic disorder at the level of group data analysis. But at the same time, the results suggest significant inter-individual differences across the patients, which may be related to each patient's individual history, woven into their neural network and affecting the individual symptoms and response to therapy.
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Neuroimagem Funcional/métodos , Imageamento por Ressonância Magnética/métodos , Neurobiologia/métodos , Transtorno de Pânico/fisiopatologia , Transtorno de Pânico/terapia , Psicoterapia/métodos , HumanosRESUMO
OBJECTIVE: Previous functional brain imaging studies have described various and contradictory activation findings in patients with panic disorder (PD). Our study focused on patients with a chronic PD, who were investigated and treated in a conventional manner, which represents the real PD patients in clinical practice. METHODS: Continuing their medication, patients were included in a six-week cognitive-behavioral therapy (CBT) program in the psychiatry department. At the onset of the study, participants underwent clinical evaluation using standard scales and were examined using fMRI while listening to verbal threat-related stimuli contrasted to neutral words. According to the therapeutic outcome, they were subsequently divided into two groups, responders, and nonresponders and the two groups were mutually compared. RESULTS: In non-responders compared to responders, we found increased pre-treatment activation in dorsolateral prefrontal cortex bilaterally, left orbitofrontal cortex, left frontal eye field, right parietal lobule and left amygdala. In addition, both groups showed negative fMRI BOLD correlation with BAI improvement and positive correlation with CGI improvement across the ROIs. We suggest that DLPFC over-activation may reveal a lack of cognitive control over emotional processing, which makes subsequent CBT less effective. CONCLUSION: Despite several limitations, we found neuroimaging predictors of poor CBT response, under the conditions of standard clinical practice, in real PD patients.
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Tonsila do Cerebelo/fisiopatologia , Terapia Cognitivo-Comportamental/métodos , Lobo Frontal/fisiopatologia , Imageamento por Ressonância Magnética , Avaliação de Resultados em Cuidados de Saúde , Transtorno de Pânico , Lobo Parietal/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Transtorno de Pânico/diagnóstico , Transtorno de Pânico/fisiopatologia , Transtorno de Pânico/terapia , PrognósticoRESUMO
OBJECTIVE: to identify predictors of good outcome in acute basilar artery occlusion (Bao). Background: acute ischemic stroke (aiS) caused by Bao is often associated with a severe and persistent neurological deficit and a high mortality rate. METHODS: the set consisted of 70 consecutive aiS patients (51 males; mean age 64.5 ± 14.5 years) with Bao. the role of the following factors was assessed: baseline characteristics, stroke risk factors, pre-event antithrombotic treatment, neurological deficit at time of treatment, estimated time to therapy procedure initiation, treatment method, recanalization rate, change in neurological deficit, post-treatment imaging findings. 30- and 90-day outcome was assessed using the modified rankin scale with a good outcome defined as a score of 0 3. RESULTS: the following statistically significant differences were found between patients with good versus poor outcomes: mean age (54.2 vs. 68.9 years; p=0.0001), presence of arterial hypertension (52.4% vs. 83.7%; p=0.015), diabetes mellitus (9.5% vs. 55.1%; p=0.0004) and severe stroke (14.3% vs. 65.3%; p=0.0002), neurological deficit at time of treatment (14.0 vs. 24.0 median of national institutes of health Stroke Scale [nihSS] points; p=0.001), successful recanalization (90.0% vs. 54.2%; p=0.005), change in neurological deficit (12.0 vs. 1.0 median difference of nihSS points; p=0.005). Stepwise binary logistic regression analysis identified age (or=0.932, 95% Ci=0.8820.984; p=0.012), presence of diabetes mellitus (or=0.105, 95% Ci=0.018-0.618; p=0.013) and severe stroke (or=0.071, 95% Ci=0.013-0.383; p=0.002) as significant independent negative predictors of good outcome. CONCLUSIONS: in the present study, higher age, presence of diabetes mellitus and severe stroke were identified as significant independent negative predictors of good outcome.
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Arteriopatias Oclusivas/diagnóstico , Arteriopatias Oclusivas/epidemiologia , Artéria Basilar/patologia , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento , Insuficiência Vertebrobasilar/diagnóstico , Insuficiência Vertebrobasilar/epidemiologiaRESUMO
Degenerative cervical myelopathy (DCM) represents the final consequence of a series of degenerative changes in the cervical spine, resulting in cervical spinal canal stenosis and mechanical stress on the cervical spinal cord. This process leads to subsequent pathophysiological processes in the spinal cord tissues. The primary mechanism of injury is degenerative compression of the cervical spinal cord, detectable by magnetic resonance imaging (MRI), serving as a hallmark for diagnosing DCM. However, the relative resilience of the cervical spinal cord to mechanical compression leads to clinical-radiological discordance, i.e., some individuals may exhibit MRI findings of DCC without the clinical signs and symptoms of myelopathy. This degenerative compression of the cervical spinal cord without clinical signs of myelopathy, potentially serving as a precursor to the development of DCM, remains a somewhat controversial topic. In this review article, we elaborate on and provide commentary on the terminology, epidemiology, natural course, diagnosis, predictive value, risks, and practical management of this condition-all of which are subjects of ongoing debate.
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In post-stroke spasticity (PSS), effective treatment with botulinum neurotoxin (BoNT) is associated with transient decrease in activation of the ipsilesional superior parietal lobule (SPL) and intraparietal sulcus (IPS). We hypothesized that this would be reflected in changes in resting-state functional connectivity (rsFC) of the SPL/IPS. Our aim was therefore to assess rsFC of the ipsilesional SPL/IPS in chronic stroke patients with hemiparesis both with and without PSS and to explore the relationship between SPL/IPS rsFC and PSS severity. To this end, fourteen chronic stroke patients with upper limb weakness and PSS (the PSS group) and 8 patients with comparable weakness but no PSS (the control group) underwent clinical evaluation and 3 fMRI examinations, at baseline (W0) and 4 and 11 weeks after BoNT (W4 and W11, respectively). Seed-based rsFC of the atlas-based SPL and IPS was evaluated using a group×time interaction analysis and a correlation analysis with PSS severity (modified Ashworth scale), integrity of the ipsilesional somatosensory afferent pathway (evoked potential N20 latency), and age. In the PSS group, transient improvement in PSS was associated with increase in rsFC between the ipsilesional IPS and the contralesional SPL at W4. The interhemispheric connectivity was negatively correlated with PSS severity at baseline and with PSS improvement at W4. We propose adaptation of the internal forward model as the putative underlying mechanism and discuss its possible association with increased limb use, diminished spastic dystonia, or improved motor performance, as well as its potential contribution to the clinical effects of BoNT.
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Toxinas Botulínicas Tipo A , Fármacos Neuromusculares , Acidente Vascular Cerebral , Humanos , Toxinas Botulínicas Tipo A/uso terapêutico , Espasticidade Muscular , Fármacos Neuromusculares/uso terapêutico , Acidente Vascular Cerebral/complicações , Lobo Parietal , Imageamento por Ressonância MagnéticaRESUMO
The term 'endemic parkinsonism' refers to diseases that manifest with a dominant parkinsonian syndrome, which can be typical or atypical, and are present only in a particular geographically defined location or population. Ten phenotypes of endemic parkinsonism are currently known: three in the Western Pacific region; two in the Asian-Oceanic region; one in the Caribbean islands of Guadeloupe and Martinique; and four in Europe. Some of these disease entities seem to be disappearing over time and therefore are probably triggered by unique environmental factors. By contrast, other types persist because they are exclusively genetically determined. Given the geographical clustering and potential overlap in biological and clinical features of these exceptionally interesting diseases, this Review provides a historical reference text and offers current perspectives on each of the 10 phenotypes of endemic parkinsonism. Knowledge obtained from the study of these disease entities supports the hypothesis that both genetic and environmental factors contribute to the development of neurodegenerative diseases, not only in endemic parkinsonism but also in general. At the same time, this understanding suggests useful directions for further research in this area.
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Transtornos Parkinsonianos , Humanos , Transtornos Parkinsonianos/epidemiologia , Transtornos Parkinsonianos/genética , Guadalupe/epidemiologia , Europa (Continente) , Fenótipo , BiologiaRESUMO
Parkinson's disease (PD) is a neurodegenerative disorder with highly heterogeneous clinical manifestations. This fact has prompted many attempts to divide PD patients into clinical subgroups. This could lead to a better recognition of pathogenesis, improving targeted treatment and the prognosis of PD patients. The aim of the present study was to obtain cerebrospinal fluid (CSF) samples in PD patients and to search for a relationship between neurodegenerative CSF markers (tau protein, beta-amyloid(1-42) and index tau protein/beta-amyloid(1-42)) and the clinical subtypes. PD patients were divided into three subgroups: early disease onset (EDO), tremor-dominant PD (TD-PD), and non-tremor dominant PD (NT-PD) according to the previously published classification. Neurodegenerative markers in the CSF were assessed in these three groups of patients suffering from PD (EDO-17, TD-15, NT-16 patients) and in a control group (CG) of 19 patients suffering from non-degenerative neurological diseases and 18 patients with Alzheimer's disease (AD). The NT-PD patients were found to have significantly higher levels of CSF tau protein and index tau/beta than the control subjects and other Parkinsonian subgroups, but no significant differences in these markers were found between AD and NT-PD patients. In the context of more rapid clinical progression and more pronounced neuropathological changes in the NT-PD patient group, our results corroborate the opinion that CSF level of tau protein may be regarded as a potential laboratory marker of the presence and severity of neurodegeneration.
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Peptídeos beta-Amiloides/líquido cefalorraquidiano , Doença de Parkinson/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Adulto , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/psicologia , FenótipoRESUMO
Converging data on focal dystonias suggest a widespread disorder of somatosensory processing. The aims of our study were, first, to assess somatosensory activation patterns in cervical dystonia (CD) beyond the representation of the affected body parts and, second, to search for task-related activation changes induced by botulinum toxin type-A (BoNT-A) therapy. Functional magnetic resonance imaging (MRI) during electrical median nerve stimulation was employed in seven CD patients and nine controls; the examination was repeated 4 weeks after BoNT-A application to dystonic neck muscles. The pretreatment activation map of patients showed activation in the contralateral primary somatosensory cortex, but missing activation in the secondary somatosensory cortex and insula, in contrast to controls and patients after treatment. Clinically significant effect of BoNT-A therapy was associated with a significant increase of BOLD response in the contralateral secondary somatosensory, insular, and inferior parietal cortices. The posttreatment somatosensory maps of patients did not significantly differ from controls. This study has brought evidence of widespread disruption of somatosensory processing in CD and its modification with BoNT-A therapy.
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Toxinas Botulínicas Tipo A/farmacologia , Fármacos Neuromusculares/farmacologia , Córtex Somatossensorial/fisiopatologia , Distúrbios Somatossensoriais/tratamento farmacológico , Distúrbios Somatossensoriais/fisiopatologia , Torcicolo/tratamento farmacológico , Torcicolo/fisiopatologia , Adulto , Toxinas Botulínicas Tipo A/uso terapêutico , Feminino , Humanos , Injeções Intramusculares/métodos , Masculino , Pessoa de Meia-Idade , Músculos do Pescoço/efeitos dos fármacos , Músculos do Pescoço/inervação , Músculos do Pescoço/fisiopatologia , Fármacos Neuromusculares/uso terapêutico , Cintilografia , Córtex Somatossensorial/diagnóstico por imagem , Distúrbios Somatossensoriais/diagnóstico por imagem , Torcicolo/diagnóstico por imagemRESUMO
The GAITFAST study (gait recovery in patients after acute ischemic stroke) aims to compare the effects of treadmill-based robot-assisted gait training (RTGT) and therapist-assisted treadmill gait training (TTGT) added to conventional physical therapy in first-ever ischemic stroke patients. GAITFAST (Clinicaltrials.gov identifier: NCT04824482) was designed as a single-blind single-center prospective randomized clinical trial with two parallel groups and a primary endpoint of gait speed recovery up to 6 months after ischemic stroke. A total of 120 eligible and enrolled participants will be randomly allocated (1:1) in TTGT or RTGT. All enrolled patients will undergo a 2-week intensive inpatient rehabilitation including TTGT or RTGT followed by four clinical assessments (at the beginning of inpatient rehabilitation 8-15 days after stroke onset, after 2 weeks, and 3 and 6 months after the first assessment). Every clinical assessment will include the assessment of gait speed and walking dependency, fMRI activation measures, neurological and sensorimotor impairments, and gait biomechanics. In a random selection (1:2) of the 120 enrolled patients, multimodal magnetic resonance imaging (MRI) data will be acquired and analyzed. This study will provide insight into the mechanisms behind poststroke gait behavioral changes resulting from intensive rehabilitation including assisted gait training (RTGT or TTGT) in early subacute IS patients.
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Degenerative spinal cord compression is a frequent pathological condition with increasing prevalence throughout aging. Initial non-myelopathic cervical spinal cord compression (NMDC) might progress over time into potentially irreversible degenerative cervical myelopathy (DCM). While quantitative MRI (qMRI) techniques demonstrated the ability to depict intrinsic tissue properties, longitudinal in-vivo biomarkers to identify NMDC patients who will eventually develop DCM are still missing. Thus, we aim to review the ability of qMRI techniques (such as diffusion MRI, diffusion tensor imaging (DTI), magnetization transfer (MT) imaging, and magnetic resonance spectroscopy (1H-MRS)) to serve as prognostic markers in NMDC. While DTI in NMDC patients consistently detected lower fractional anisotropy and higher mean diffusivity at compressed levels, caused by demyelination and axonal injury, MT and 1H-MRS, along with advanced and tract-specific diffusion MRI, recently revealed microstructural alterations, also rostrally pointing to Wallerian degeneration. Recent studies also disclosed a significant relationship between microstructural damage and functional deficits, as assessed by qMRI and electrophysiology, respectively. Thus, tract-specific qMRI, in combination with electrophysiology, critically extends our understanding of the underlying pathophysiology of degenerative spinal cord compression and may provide predictive markers of DCM development for accurate patient management. However, the prognostic value must be validated in longitudinal studies.
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BACKGROUND: In this study we evaluated the impact of location of deep brain stimulation electrode active contact in different parts of the subthalamic nucleus on improvement of non-motor symptoms in patients with Parkinson's disease. METHODS: The subthalamic nucleus was divided into two (dorsolateral/ventromedial) and three (dorsolateral, medial, ventromedial) parts. 37 deep brain stimulation electrodes were divided according to their active contact location. Correlation between change in non-motor symptoms before and one and four months after deep brain stimulation electrode implantation and the location of active contact was made. RESULTS: In dividing the subthalamic nucleus into three parts, no electrode active contact was placed ventromedially, 28 active contacts were located in the medial part and 9 contacts were placed dorsolaterally. After one and four months, no significant difference was found between medial and dorsolateral positions. In the division of the subthalamic nucleus into two parts, 13 contacts were located in the ventromedial part and 24 contacts were placed in the dorsolateral part. After one month, significantly greater improvement in the Non-motor Symptoms Scale for Parkinson's disease (P=0.045) was found on dorsolateral left-sided stimulation, but no significant differences between the ventromedial and dorsolateral positions were found on the right side. CONCLUSION: This study demonstrated the relationship between improvement of non-motor symptoms and the side (hemisphere, left/right) of the deep brain stimulation electrode active contact, rather than its precise location within specific parts of the subthalamic nucleus in patients treated for advanced Parkinson's disease.
Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Eletrodos , Humanos , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiologia , Resultado do TratamentoRESUMO
Background: Degenerative cervical spinal cord compression is becoming increasingly prevalent, yet the MRI criteria that define compression are vague, and vary between studies. This contribution addresses the detection of compression by means of the Spinal Cord Toolbox (SCT) and assesses the variability of the morphometric parameters extracted with it. Methods: Prospective cross-sectional study. Two types of MRI examination, 3 and 1.5 T, were performed on 66 healthy controls and 118 participants with cervical spinal cord compression. Morphometric parameters from 3T MRI obtained by Spinal Cord Toolbox (cross-sectional area, solidity, compressive ratio, torsion) were combined in multivariate logistic regression models with the outcome (binary dependent variable) being the presence of compression determined by two radiologists. Inter-trial (between 3 and 1.5 T) and inter-rater (three expert raters and SCT) variability of morphometric parameters were assessed in a subset of 35 controls and 30 participants with compression. Results: The logistic model combining compressive ratio, cross-sectional area, solidity, torsion and one binary indicator, whether or not the compression was set at level C6/7, demonstrated outstanding compression detection (area under curve =0.947). The single best cut-off for predicted probability calculated using a multiple regression equation was 0.451, with a sensitivity of 87.3% and a specificity of 90.2%. The inter-trial variability was better in Spinal Cord Toolbox (intraclass correlation coefficient was 0.858 for compressive ratio and 0.735 for cross-sectional area) compared to expert raters (mean coefficient for three expert raters was 0.722 for compressive ratio and 0.486 for cross-sectional area). The analysis of inter-rater variability demonstrated general agreement between SCT and three expert raters, as the correlations between SCT and raters were generally similar to those of the raters between one another. Conclusions: This study demonstrates successful semi-automated compression detection based on four parameters. The inter-trial variability of parameters established through two MRI examinations was conclusively better for Spinal Cord Toolbox compared with that of three experts' manual ratings.