Publications by authors named "Jose Miguel Bras"

Lysosomal storage disorders are a group of about 50 rare metabolic diseases that result from defects in lysosomal function. The majority is recessively inherited and caused by mutations in genes encoding lysosomal proteins as the basis for its pathobiology. The lysosome plays a pivotal role in a cell's ability to recycle and degrade unwanted material.

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Objective: To identify new genes and risk factors associated with frontotemporal dementia (FTD). Several genes and loci have been associated with different forms of FTD, but a large number of families with dementia do not harbor mutations in these genes.

Design: Whole-exome sequencing and whole-genome genotyping were performed in all patients.

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Alzheimer's disease (AD) is a genetically complex disorder for which the definite diagnosis is only accomplished postmortem. Mutations in 3 genes (APP, PSEN1, and PSEN2) are known to cause AD, but a large number of familial cases do not harbor mutations in these genes and several unidentified genes that contain disease-causing mutations are thought to exist. We performed whole exome sequencing in a Turkish patient clinically diagnosed with Alzheimer's disease from a consanguineous family with a complex history of neurological and immunological disorders and identified a mutation in NOTCH3 (p.

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It is hoped that an understanding of the genetic basis of Parkinson's disease (PD) will lead to an appreciation of the molecular pathogenesis of disease, which in turn will highlight potential points of therapeutic intervention. It is also hoped that such an understanding will allow identification of individuals at risk for disease prior to the onset of motor symptoms. A large amount of work has already been performed in the identification of genetic risk factors for PD and some of this work, particularly those efforts that focus on genes implicated in monogenic forms of PD, have been successful, although hard won.

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Mutations in three genes (PSEN1, PSEN2, and APP) have been identified in patients with early-onset (<65 years) Alzheimer's disease (AD). We performed a screening for mutations in the coding regions of presenilins, as well as exons 16 and 17 of the APP gene in a total of 231 patients from the Iberian peninsular with a clinical diagnosis of early-onset AD (mean age at onset of 52.9 years; range 31-64).

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Mutations in the progranulin (PGRN) gene were recently described as the cause of ubiquitin positive frontotemporal dementia (FTD) in many families. Different frequencies of these genetic changes have been reported in diverse populations leading us to determine if these mutations were a major cause of FTD in the Portuguese population. The entire coding sequence plus exon 0 of PGRN were sequenced in a consecutive series of 46 FTD/CBS Portuguese patients.

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Background: Several lines of evidence in the literature have shown that inflammation is involved in the pathogenesis of Alzheimer's disease (AD). However, the results from the evaluation of serum inflammatory markers in AD patients have been controversial.

Objective: To determine if any differences exist in the monocytic secretion pattern of IL-1beta, IL-6, IL-12 and TNF-alpha from mild cognitive impairment (MCI) and AD patients, when compared with healthy age-matched controls.

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LRRK2 mutations have recently been described in families with Parkinson's disease. Here we show that one of them (G2019S) is present in 6% (7 of 124) unrelated cases of disease in a clinic-based sample series from central Portugal, but not present in 126 controls from the same population. Thus, LRRK2 mutations appear to be a common cause of typical Parkinson's disease and as such will alter clinical practice.

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