NEU - Artigos publicados em revistas não indexadas
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- Diagnosis of stroke by the nonneurologist: a validation study.Publication . Ferro, J; Pinto, A; Falcão, I; Rodrigues, G; Ferreira, J; Falcão, F; Azevedo, E; Canhão, P; Melo, T; Rosas, MJ; Oliveira, V; Salgado, AVBACKGROUND AND PURPOSE: The first medical contact of an acute stroke victim is often a nonneurologist. Validation of stroke diagnosis made by these medical doctors is poorly known. The present study seeks to validate the stroke diagnoses made by general practitioners (GPs) and hospital emergency service physicians (ESPs). METHODS: Validation through direct interview and examination by a neurologist was performed for diagnoses of stroke made by GPs in patients under their care and doctors working at the emergency departments of 3 hospitals. RESULTS: Validation of the GP diagnosis was confirmed in 44 cases (85%); 3 patients (6%) had transient ischemic attacks and 5 (9%) suffered from noncerebrovascular disorders. Validation of the ESP diagnosis was confirmed in 169 patients (91%); 16 (9%) had a noncerebrovascular diagnosis. Overall, the most frequent conditions misdiagnosed as stroke were neurological in nature (cerebral tumor, 3; subdural hematoma, 1; seizure, 1; benign paroxysmal postural vertigo, 1; peripheral facial palsy, 2; psychiatric condition, 6; and other medical disorders, 7). CONCLUSIONS: In the majority of cases, nonneurologists (either GPs or ESPs) can make a correct diagnosis of acute stroke. Treatment of acute stroke with drugs that do not cause serious side effects can be started before evaluation by a neurologist and CT scan.
- Involuntary rhythmic leg movements time-locked with the respiratory cyclePublication . Leal, A; Calado, EInvoluntary rhythmic leg movements in childhood is an uncommon condition, the generators of which remain unknown. We report on a male 3 years of age with distinct features providing important clues concerning the location of one of these generators. At the age of 7 months, the previously healthy young male started with low frequency, rhythmic, and continuous (both during wakefulness and sleep) flexion/extension movements of the lower limbs. Movements interfered significantly with gait acquisition, and, despite normal cognitive development, he was able to walk only at age 2 years, 4 months. The neurologic examination revealed the absence of automatic stepping in the neonatal period, but was otherwise normal. A polygraphic electroencephalogram/electromyogram (EEG/EMG) recording, at the age of 2 years, 9 months, revealed rhythmic and synchronous legs with EMG activity at 0.5 Hz. A more complete polygraphic recording at the age of 3 years, 10 months, showed a lower frequency (0.35 Hz) for the movements, which were time-locked with the respiratory cycle. Magnetic resonance imaging (MRI) of the brain revealed an increased T(2) signal in the upper medulla-lower pons regions. The generator of the rhythmic legs movements is postulated to be the respiratory center, connecting with the reticulospinal projecting neurons through an aberrant pathway.
- Behavioral response to headache: a comparison between migraine and tension-type headache.Publication . Martins, I; Parreira, EOBJECTIVE: To compare patients with migraine and tension-type headache in their behavior during the attacks and the maneuvers used to relieve the pain. BACKGROUND: Patients with headache often perform nonpharmacological measures to relieve the pain, but it is not known if these behaviors vary with the diagnosis, clinical features, and pathogenesis. METHODS: One hundred consecutive patients with either migraine (n = 72 ) or tension-type headache (n = 28) were questioned (including the use of a checklist) concerning their usual behavior during the attacks and nonpharmacological maneuvers performed to relieve the pain. The results of the two types of headache were compared. RESULTS: Patients with migraine tended to perform more maneuvers than individuals with tension-type headache (mean, 6.2 versus 3). These maneuvers included pressing and applying cold stimuli to the painful site, trying to sleep, changing posture, sitting or reclining in bed (using more pillows than usual to lay down), isolating themselves, using symptomatic medication, inducing vomiting, changing diet, and becoming immobile during the attacks. The only measure predominantly reported by patients with tension-type headache was scalp massage. However, the benefit derived from these measures was not significantly different between the two groups (except for a significantly better response to isolation, local pressure, local cold stimulation, and symptomatic medication in migraineurs). CONCLUSIONS: The behavior of patients during headache attacks varies with the diagnosis. Measures that do not always result in pain relief are performed to prevent its worsening or to improve associated symptoms. These behavioral differences may be due to the different pathogenesis of the attacks or to different styles of dealing with the pain. They can also aid the differential diagnosis between headaches in doubtful cases.
- Neuronal migration defects in the Dreher (Lmx1a) mutant mouse: role of disorders of the glial limiting membranePublication . Costa, C; Harding, B; Copp, ADreher (dr(J)) is an autosomal recessive mutation in the newly identified LIM homeobox gene, Lmx1a. The homozygous mutant phenotype includes misplaced neurons (heterotopia) in the cerebral cortex, cerebellum and hippocampus, which mimic the mild end of the spectrum of neuronal migration disorders in humans. Heterotopic neurons are found mainly in the normally cell-sparse layer I within the cerebral hemispheres of dr(J) homozygotes. Neu-N immunostaining confirms the neuronal nature of these heterotopic cells, while bromodeoxyuridine-birthdating shows that the misplaced neurons are generated predominantly during the late stages of corticogenesis (E15-E17), suggesting an over-migration of neurons destined for layer II. Immunohistochemistry for laminin, and staining of reticulin fibres, reveals disruption of the glial limiting membrane specifically overlying the areas of heterotopic neurons. Factor VIII (von Willebrand factor) staining shows an abnormal vascular network in layer I, associated with the fragmented glial limiting membrane. Layer I astrocytes, recognized by immunostaining for glial fibrillary acidic protein, exhibit attachment of their end feet to the fragmented glial limiting membrane. We suggest that disruption of the glial limiting membrane is central to the pathogenesis of heterotopic neurons in dreher, perhaps via defective radial glial-guided neuronal migration.
- Interictal spike EEG source analysis in hypothalamic hamartoma epilepsyPublication . Leal, A; Passão, V; Calado, E; Vieira, J; Cunha, JObjective: The epilepsy associated with the hypothalamic hamartomas constitutes a syndrome with peculiar seizures, usually refractory to medical therapy, mild cognitive delay, behavioural problems and multifocal spike activity in the scalp electroencephalogram (EEG). The cortical origin of spikes has been widely assumed but not specifically demonstrated. Methods: We present results of a source analysis of interictal spikes from 4 patients (age 2–25 years) with epilepsy and hypothalamic hamartoma, using EEG scalp recordings (32 electrodes) and realistic boundary element models constructed from volumetric magnetic resonance imaging (MRIs). Multifocal spike activity was the most common finding, distributed mainly over the frontal and temporal lobes. A spike classification based on scalp topography was done and averaging within each class performed to improve the signal to noise ratio. Single moving dipole models were used, as well as the Rap-MUSIC algorithm. Results: All spikes with good signal to noise ratio were best explained by initial deep sources in the neighbourhood of the hamartoma, with late sources located in the cortex. Not a single patient could have his spike activity explained by a combination of cortical sources. Conclusions: Overall, the results demonstrate a consistent origin of spike activity in the subcortical region in the neighbourhood of the hamartoma, with late spread to cortical areas.
- Trinucleotide repeats in 202 families with ataxia: a small expanded (CAG)n allele at the SCA17 locus.Publication . Silveira, I; Miranda, C; Guimarães, L; Moreira, MC; Alonso, I; Mendonça, P; Ferro, A; Pinto-Basto, J; Coelho, J; Ferreirinha, F; Poirier, J; Parreira, E, et al.BACKGROUND: Ten neurodegenerative disorders characterized by spinocerebellar ataxia (SCA) are known to be caused by trinucleotide repeat (TNR) expansions. However, in some instances the molecular diagnosis is considered indeterminate because of the overlap between normal and affected allele ranges. In addition, the mechanism that generates expanded alleles is not completely understood. OBJECTIVE: To examine the clinical and molecular characteristics of a large group of Portuguese and Brazilian families with ataxia to improve knowledge of the molecular diagnosis of SCA. PATIENTS AND METHODS: We have (1) assessed repeat sizes at all known TNR loci implicated in SCA; (2) determined frequency distributions of normal alleles and expansions; and (3) looked at genotype-phenotype correlations in 202 unrelated Portuguese and Brazilian patients with SCA. Molecular analysis of TNR expansions was performed using polymerase chain reaction amplification. RESULTS: Patients from 110 unrelated families with SCA showed TNR expansions at 1 of the loci studied. Dominantly transmitted cases had (CAG)(n) expansions at the Machado-Joseph disease gene (MJD1) (63%), at SCA2 (3%), the gene for dentatorubropallidoluysian atrophy (DRPLA) (2%), SCA6 (1%), or SCA7 (1%) loci, or (CTG)(n) expansions at the SCA8 (2%) gene, whereas (GAA)(n) expansions in the Freidreich ataxia gene (FRDA) were found in 64% of families with recessive ataxia. Isolated patients also had TNR expansions at the MJD1 (6%), SCA8 (6%), or FRDA (8%) genes; in addition, an expanded allele at the TATA-binding protein gene (TBP), with 43 CAGs, was present in a patient with ataxia and mental deterioration. Associations between frequencies of SCA2 and SCA6 and a frequency of large normal alleles were found in Portuguese and Brazilian individuals, respectively. Interestingly, no association between the frequencies of DRPLA and large normal alleles was found in the Portuguese group. CONCLUSIONS: Our results show that (1) a significant number of isolated cases of ataxia are due to TNR expansions; (2) expanded DRPLA alleles in Portuguese families may have evolved from an ancestral haplotype; and (3) small (CAG)(n) expansions at the TBP gene may cause SCA17.
- Acquired immunodeficiency syndrome and the risk of strokePublication . Cole, J; Pinto, A; Hebel, J; Buchholz, D; Earley, C; Johnson, C; Macko, R; Price, T; Sloan, M; Stern, B; Wityk, R; Wozniak, M; Kittner, SBACKGROUND AND PURPOSE: Although acquired immunodeficiency syndrome (AIDS) is thought to increase the risk of stroke, few data exist to quantify this risk. This is the first population-based study to quantify the AIDS-associated risk of stroke. METHODS: We identified all incident ischemic stroke (IS) and intracerebral hemorrhage (ICH) cases among young adults 15 to 44 years of age in central Maryland and Washington, DC, who were discharged from any of the 46 hospitals in the study area in 1988 and 1991. Using data from the medical records, 2 neurologists reviewed each case to confirm the diagnosis. Cases of AIDS among these patients with stroke were defined using Centers for Disease Control and Prevention criteria (1987). The number of cases of AIDS in the central Maryland and Washington population during 1988 and 1991 was determined from regional health departments working with the Centers for Disease Control and Prevention. Poisson regression was used to estimate the age-, race-, and sex-adjusted relative risk of stroke associated with AIDS. RESULTS: There were 385 IS cases (6 with AIDS) and 171 ICH cases (6 with AIDS). The incidences of IS and ICH among persons with AIDS were both 0.2% per year. AIDS conferred an adjusted relative risk of 13.7 (95% confidence interval [CI], 6.1 to 30.8) for IS and 25.5 (95% CI, 11.2 to 58.0) for ICH. After exclusion of 5 cases of stroke in AIDS patients in whom other potential causes were identified, AIDS patients continued to have an increased risk of stroke with an adjusted relative risk of 9.1 (95% CI, 3.4 to 24.6) for IS and 12.7 (95% CI, 4.0 to 40.0) for ICH. CONCLUSIONS: This population-based study found that AIDS is strongly associated with both IS and ICH.
- Nonsense mutation in TITF1 in a Portuguese family with benign hereditary choreaPublication . Costa, MC; Costa, C; Silva, A; Evangelista, P; Santos, L; Ferro, A; Sequeiros, J; Maciel, PBenign hereditary chorea (BHC) is an autosomaldominant disorder of early onset characterized by a slowly progressing or nonprogressing chorea, without cognitive decline or other progressive neurologic dysfunction, but also by the existence of heterogeneity of the clinical presentation within and among families. The genetic cause of BHC is the presence of either point mutations or deletions in the thyroid transcription factor 1 gene (TITF1). We studied a Portuguese BHC family composed of two probands: a mother and her only son. The patients were identified in a neurology out-patient clinic showing mainly involuntary choreiform movements since childhood, myoclonic jerks, falls, and dysarthria. We performed magnetic resonance imaging (MRI), electroencephalogram (EEG), nerve conduction studies, thyroid ultrasound scan, biochemical thyroid tests, and electrocardiogram (ECG). We excluded Huntington disease by appropriate genetic testing and sequenced the entire TITF1 gene for both patients. The patients showed MRI alterations: (1) in the mother, abnormal hyperintense pallida and cortical cerebral/cerebellar atrophy; and (2) in the son, small hyperintense foci in the cerebellum and subtle enlargement of the fourth ventricle. Sequence analysis of the TITF1 gene in these patients revealed the presence of a heterozygous C > T substitution at nucleotide 745, leading to the replacement of a glutamine at position 249 for a premature stop codon. A previously undescribed nonsense mutation in the TITF1 gene was identified as being the genetic cause of BHC in this family.