Browsing by Author "Vieira, JP"
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- 0 Impacto da lnvestigação Neurofisiológica na Referenciação para Cirurgia da Epilepsia na Esclerose TuberosaPublication . Borges, D; Calado, E; Vieira, JP; Moreira, A; Leal, A; Dias, AI
- Acroparestesias, Diarreia e Dor Abdominal Recorrente – a Importância do “Awareness” no Diagnóstico da Doença RaraPublication . Freitas, J; Ferreira, AC; Vieira, JP; Candeias, F; Brito, MJ; Ramos, M; Farela Neves, J; Oliveira, L; Antunes, D; Sequeira, SIntrodução: A doença de Anderson-Fabry é uma doença hereditária ligada ao cromossoma X causada pela deficiência da enzima lisossomal alfa-galactosidase com acumulação de globotriaosilceramida e comprometimento multissistémico progressivo. No sexo masculino, manifesta-se geralmente na infância e adolescência com acroparestesias, angioqueratomas e sintomas gastrointestinais, evoluindo na idade adulta precoce com complicações cardíacas, neurológicas e renais. Caso clínico: Jovem de 14 anos, sexo masculino, internado por infeção respiratória. Na história clínica constatou-se quadro com cinco anos de evolução de dor abdominal intermitente, diarreia crónica e episódios recorrentes de dor nas mãos e pés, tipo queimadura, agravados pela febre. O tio materno tinha um quadro clínico semelhante. Foi feita investigação reumatológica, gastrointestinal, auto-imune, neurológica e genética, mas foi o “awareness” diagnóstico para esta entidade que motivou o pedido da atividade enzimática da alfa-galactosidase A e confirmou o diagnóstico de doença de Anderson-Fabry. O estudo molecular do gene GLA revelou, em hemizigotia, a mutação c.195-1G>A. O estudo familiar confirmou a doença no tio materno e em mais um familiar do sexo masculino e três do sexo feminino Comentários: O diagnóstico da doença de Anderson-Fabry é frequentemente tardio devido à raridade da doença, inespecificidade das manifestações iniciais e ao vasto espectro de diagnósticos diferenciais. O diagnóstico precoce é importante pela intervenção na progressão da doença com terapêutica enzimática de substituição. O rastreio familiar é fundamental para a detecção de casos pré-sintomáticos e sintomáticos ainda não diagnosticados.
- Adding Evidence to the Role of NEUROG1 in Congenital Cranial Dysinnervation DisordersPublication . Dupont, J; Vieira, JP; Tavares, AL; Conceição, C; Khan, S; Bertoli-Avella, AM; Sousa, ABCongenital cranial dysinnervation disorders (CCDDs) are a heterogeneous group of neurodevelopmental phenotypes caused by a primary disturbance of innervation due to deficient, absent, or misguided cranial nerves. Although some CCDDs genes are known, several clinical phenotypes and their aetiologies remain to be elucidated. We describe a 12-year-old boy with hypotonia, developmental delay, sensorineural hearing loss, and keratoconjunctivitis due to lack of corneal reflex. He had a long expressionless face, severe oromotor dysfunction, bilateral agenesis/severe hypoplasia of the VIII nerve with marked atresia of the internal auditory canals and cochlear labyrinth malformation. Trio-exome sequencing identified a homozygous loss of function variant in the NEUROG1 gene (NM_006161.2: c.202G > T, p.Glu68*). NEUROG1 is considered a causal candidate for CCDDs based on (i) the previous report of a patient with a homozygous gene deletion and developmental delay, deafness due to absent bilateral VIII nerves, and severe oromotor dysfunction; (ii) a second patient with a homozygous NEUROG1 missense variant and corneal opacity, absent corneal reflex and intellectual disability; and (iii) the knockout mouse model phenotype which highly resembles the disorder observed in humans. Our findings support the growing compelling evidence that loss of NEUROG1 leads to a very distinctive disorder of cranial nerves development.
- Analysis of Highly Conserved Regions of the 3'UTR of MECP2 Gene in Patients with Clinical Diagnosis of Rett Syndrome and Other Disorders Associated with Mental RetardationPublication . Santos, M; Yan, J; Temudo, T; Oliveira, G; Vieira, JP; Fen, J; Sommer, S; Maciel, PIn this work we explored the role of the 3'UTR of the MECP2 gene in patients with clinical diagnosis of RTT and mental retardation; focusing on regions of the 3'UTR with almost 100% conservation at the nucleotide level among mouse and human. By mutation scanning (DOVAM-S technique) the MECP2 3'UTR of a total of 66 affected females were studied. Five3'UTR variants in the MECP2 were found (c.1461+9G>A, c.1461+98insA, c.2595G>A, c.9961C>G and c.9964delC) in our group of patients. None of the variants found is located in putative protein-binding sites nor predicted to have a pathogenic role. Our data suggest that mutations in this region do not account for a large proportion of the RTT cases without a genetic explanation.
- Analysis of the Dynamics and Origin of Epileptic Activity in Patients with Tuberous Sclerosis Evaluated for Surgery of EpilepsyPublication . Leal, A; Dias, AI; Vieira, JP; Moreira, A; Távora, L; Calado, EObjective: The epilepsies associated with the tuberous sclerosis complex (TSC) are very often refractory to medical therapy. Surgery for epilepsy is an effective alternative when the critical link between the localization of seizure onset in the scalp and a particular cortical tuber can be established. In this study we perform analysis of ictal and interictal EEG to improve such link. Methods: The ictal and interictal recordings of four patients with TSC undergoing surgery for epilepsy were submitted to independent component analysis (ICA), followed by source analysis, using the sLORETA algorithm. The localizations obtained for the ictal EEG and for the average interictal spikes were compared. Results: The ICA of ictal EEG produced consistent results in different events, and there was good agreement with the tubers that were successfully removed in three of the four patients (one patient refused surgery). In some patients there was a large discrepancy between the localization of ictal and interictal sources. The interictal activity produced more widespread source localizations. Conclusions: The use of ICA of ictal EEG followed by the use of source analysis methods in four cases of epilepsy and TSC was able to localize the epileptic generators very near the lesions successfully removed in surgery for epilepsy. Significance: The ICA of ictal EEG events may be a useful add-on to the tools used to establish the connection between epileptic scalp activity and the cortical tubers originating it, in patients with TSC considered for surgery of epilepsy.
- Analysis of the EEG Dynamics of Epileptic Activity in Gelastic Seizures Using Decomposition in Independent ComponentsPublication . Leal, A; Dias, AI; Vieira, JPObjective: Gelastic seizures are a frequent and well established manifestation of the epilepsy associated with hypothalamic hamartomas. The scalp EEG recordings very seldom demonstrate clear spike activity and the information about the ictal epilepsy dynamics is limited. In this work, we try to isolate epileptic rhythms in gelastic seizures and study their generators. Methods: We extracted rhythmic activity from EEG scalp recordings of gelastic seizures using decomposition in independent components (ICA) in three patients, two with hypothalamic hamartomas and one with no hypothalamic lesion. Time analysis of these rhythms and inverse source analysis was done to recover their foci of origin and temporal dynamics. Results: In the two patients with hypothalamic hamartomas consistent ictal delta (2–3 Hz) rhythms were present, with subcortical generators in both and a superficial one in a single patient. The latter pattern was observed in the patient with no hypothalamic hamartoma visible in MRI. The deep generators activated earlier than the superficial ones, suggesting a consistent sub-cortical origin of the rhythmical activity. Conclusions: Our data is compatible with early and brief epileptic generators in deep sub-cortical regions and more superficial ones activating later. Significance: Gelastic seizures express rhythms on scalp EEG compatible with epileptic activity originating in sub-cortical generators and secondarily involving cortical ones.
- Analysis of the Generators of Epileptic Activity in Early-Onset Childhood Benign Occipital Lobe EpilepsyPublication . Leal, A; Nunes, S; Dias, AI; Vieira, JP; Moreira, A; Calado, EObjective: The Panayiotopoulos type of idiopathic occipital epilepsy has peculiar and easily recognizable ictal symptoms, which are associated with complex and variable spike activity over the posterior scalp areas. These characteristics of spikes have prevented localization of the particular brain regions originating clinical manifestations. We studied spike activity in this epilepsy to determine their brain generators. Methods: The EEG of 5 patients (ages 7–9) was recorded, spikes were submitted to blind decomposition in independent components (ICs) and those to source analysis (sLORETA), revealing the spike generators. Coherence analysis evaluated the dynamics of the components. Results: Several ICs were recovered for posterior spikes in contrast to central spikes which originated a single one. Coherence analysis supports a model with epileptic activity originating near lateral occipital area and spreading to cortical temporal or parietal areas. Conclusions: Posterior spikes demonstrate rapid spread of epileptic activity to nearby lobes, starting in the lateral occipital area. In contrast, central spikes remain localized in the rolandic fissure. Significance: Rapid spread of posterior epileptic activity in the Panayitopoulos type of occipital lobe epilepsy is responsible for the variable and poorly localized spike EEG. The lateral occipital cortex is the primary generator of the epileptic activity.
- Anatomical and Physiological Basis of Continuous Spike-Wave of Sleep Syndrome after Early Thalamic LesionsPublication . Leal, A; Calado, E; Vieira, JP; Mendonça, C; Ferreira, JC; Ferreira, H; Carvalho, D; Furtado, F; Gomes, R; Monteiro, JPOBJECTIVE: Early neonatal thalamic lesions account for about 14% of continuous spike-wave of sleep (CSWS) syndrome, representing the most common etiology in this epileptic encephalopathy in children, and promise useful insights into the pathophysiology of the disease. METHODS: We describe nine patients with unilateral neonatal thalamic lesions which progressed to CSWS. Longitudinal whole-night and high-density electroencephalograms (EEGs) were performed, as well as detailed imaging and clinical evaluation. Visual evoked potentials were used to probe cortical excitability. RESULTS: Thalamic volume loss ranged from 19% to 94%, predominantly on medial and dorsal nuclei and sparing the ventral thalamus. Lesions produced white matter loss and ventricle enlargement on the same hemisphere, which in four patients was associated with selective loss of thalamic-cortical fibers. Cortical thickness quantification failed to reveal hemispheric asymmetries. Impact on EEG rhythms was mild, with a volume-loss-related decrease in alpha power and preservation of sleep spindles. The sleep continuous spiking was lateralized to the hemisphere with the lesion. Visual cortex stimulation in five patients with posterior cortex spiking revealed an abnormal frequency-dependent excitability at 10-20Hz on the side of the lesion. SIGNIFICANCE: Unilateral selective thalamic-cortical disconnection is a common feature in our patients and is associated with both a focal pattern of CSWS and a pathological type of frequency-dependent excitability (peak: 10-20Hz). We propose that this excitability represents an abnormal synaptic plasticity previously described as the augmenting response. This synaptic plasticity has been described as absent in the corticocortical interactions in healthy experimental animals, emerging after ablation of the thalamus and producing a frequency-dependent potentiation with a peak at 10-20Hz. Because this response is potentiated by sleep states of reduced brainstem activation and by appropriate stimulating rhythms, such as sleep spindles, the simultaneous occurrence of these two factors in nonrapid-eye-movement sleep is proposed as an explanation for CSWS in our patients.
- Aneurisma Intracraniano na CriançaPublication . Martins, L; Nunes, S; Marques, A; Vieira, JP; Gonçalves, V; Barata, DOs aneurismas cerebrais são raros na criança, embora a sua ruptura seja a principal causa de hemorragia subaracnoideia neste grupo etário. Apresenta-se o caso de uma criança de 11 anos de idade, que recorreu ao hospital por cefaleia súbita e intensa, sem história prévia de traumatismos ou infecções. O estudo clínico e imagiológico realizado foi sugestivo de hemorragia subaracnoideia. A angiografia cerebral permitiu o diagnóstico de aneurisma da bifurcação da artéria carótida interna esquerda. Foi submetida a cirurgia, com boa evolução pós-operatória. Pretende-se com este caso alertar para as dificuldades no diagnóstico diferencial de ruptura de aneurisma cerebral na criança e salientar que um diagnóstico correcto e precoce permite melhorar o prognóstico.
- Anti-N-Methyl-D-Aspartate Receptor Encephalitis with Positive Serum Antithyroid Antibodies, IgM Antibodies Against Mycoplasma Pneumoniae and Human Herpesvirus 7 PCR in the CSFPublication . Venâncio, P; Brito, MJ; Pereira, G; Vieira, JPWe report the case of a boy with an encephalopathy associated with extrapyramidal and psychiatric symptoms and anti-N-methyl-D-aspartate receptor antibodies. He had positive serum antithyroid antibodies, IgM antibodies against Mycoplasma pneumoniae and human herpesvirus 7 polymerase chain reaction in the cerebrospinal fluid. He was successfully treated with rituximab, after steroids, intravenous immunoglobulin and plasma exchange. The pathophysiology of this disorder may be post-infectious and autoimmune.