Search tips
Search criteria

Results 1-6 (6)

Clipboard (0)

Select a Filter Below

Year of Publication
1.  Neurodegenerative Disorder Risk in Idiopathic REM Sleep Behavior Disorder: Study in 174 Patients 
PLoS ONE  2014;9(2):e89741.
To estimate the risk for developing a defined neurodegenerative syndrome in a large cohort of idiopathic REM sleep behavior disorder (IRBD) patients with long follow-up.
Using the Kaplan-Meier method, we estimated the disease-free survival rate from defined neurodegenerative syndromes in all the consecutive IRBD patients diagnosed and followed-up in our tertiary referal sleep center between November 1991 and July 2013.
The cohort comprises 174 patients with a median age at diagnosis of IRBD of 69 years and a median follow-up of four years. The risk of a defined neurodegenerative syndrome from the time of IRBD diagnosis was 33.1% at five years, 75.7% at ten years, and 90.9% at 14 years. The median conversion time was 7.5 years. Emerging diagnoses (37.4%) were dementia with Lewy bodies (DLB) in 29 subjects, Parkinson disease (PD) in 22, multiple system atrophy (MSA) in two, and mild cognitive impairment (MCI) in 12. In six cases, in whom postmortem was performed, neuropathological examination disclosed neuronal loss and widespread Lewy-type pathology in the brain in each case.
In a large IRBD cohort diagnosed in a tertiary referal sleep center, prolonged follow-up indicated that the majority of patients are eventually diagnosed with the synucleinopathies PD, DLB and less frequently MSA. IRBD represented the prodromal period of these conditions. Our findings in IRBD have important implications in clinical practice, in the investigation of the early pathological events occurring in the synucleinopathies, and for the design of interventions with potential disease-modifying agents.
PMCID: PMC3935943  PMID: 24587002
2.  Rare Variants in Calcium Homeostasis Modulator 1 (CALHM1) Found in Early Onset Alzheimer’s Disease Patients Alter Calcium Homeostasis 
PLoS ONE  2013;8(9):e74203.
Calcium signaling in the brain is fundamental to the learning and memory process and there is evidence to suggest that its dysfunction is involved in the pathological pathways underlying Alzheimer’s disease (AD). Recently, the calcium hypothesis of AD has received support with the identification of the non-selective Ca2+-permeable channel CALHM1. A genetic polymorphism (p. P86L) in CALHM1 reduces plasma membrane Ca2+ permeability and is associated with an earlier age-at-onset of AD. To investigate the role of CALHM1 variants in early-onset AD (EOAD), we sequenced all CALHM1 coding regions in three independent series comprising 284 EOAD patients and 326 controls. Two missense mutations in patients (p.G330D and p.R154H) and one (p.A213T) in a control individual were identified. Calcium imaging analyses revealed that while the mutation found in a control (p.A213T) behaved as wild-type CALHM1 (CALHM1-WT), a complete abolishment of the Ca2+ influx was associated with the mutations found in EOAD patients (p.G330D and p.R154H). Notably, the previously reported p. P86L mutation was associated with an intermediate Ca2+ influx between the CALHM1-WT and the p.G330D and p.R154H mutations. Since neither expression of wild-type nor mutant CALHM1 affected amyloid ß-peptide (Aß) production or Aß-mediated cellular toxicity, we conclude that rare genetic variants in CALHM1 lead to Ca2+ dysregulation and may contribute to the risk of EOAD through a mechanism independent from the classical Aß cascade.
PMCID: PMC3775809  PMID: 24069280
3.  Distinct patterns of APP processing in the CNS in autosomal-dominant and sporadic Alzheimer disease 
Acta Neuropathologica  2012;125(2):201-213.
Autosomal-dominant Alzheimer disease (ADAD) is a genetic disorder caused by mutations in Amyloid Precursor Protein (APP) or Presenilin (PSEN) genes. Studies from families with ADAD have been critical to support the amyloid cascade hypothesis of Alzheimer disease (AD), the basis for the current development of amyloid-based disease-modifying therapies in sporadic AD (SAD). However, whether the pathological changes in APP processing in the CNS in ADAD are similar to those observed in SAD remains unclear. In this study, we measured β-site APP-cleaving enzyme (BACE) protein levels and activity, APP and APP C-terminal fragments in brain samples from subjects with ADAD carrying APP or PSEN1 mutations (n = 18), patients with SAD (n = 27) and age-matched controls (n = 22). We also measured sAPPβ and BACE protein levels, as well as BACE activity, in CSF from individuals carrying PSEN1 mutations (10 mutation carriers and 7 non-carrier controls), patients with SAD (n = 32) and age-matched controls (n = 11). We found that in the brain, the pattern in ADAD was characterized by an increase in APP β-C-terminal fragment (β-CTF) levels despite no changes in BACE protein levels or activity. In contrast, the pattern in SAD in the brain was mainly characterized by an increase in BACE levels and activity, with less APP β-CTF accumulation than ADAD. In the CSF, no differences were found between groups in BACE activity or expression or sAPPβ levels. Taken together, these data suggest that the physiopathological events underlying the chronic Aβ production/clearance imbalance in SAD and ADAD are different. These differences should be considered in the design of intervention trials in AD.
Electronic supplementary material
The online version of this article (doi:10.1007/s00401-012-1062-9) contains supplementary material, which is available to authorized users.
PMCID: PMC3623032  PMID: 23224319
Amyloid precursor protein; Autosomal-dominant Alzheimer disease; β-Site APP-cleaving enzyme; Presenilin; β-Amyloid
4.  Atypical Creutzfeldt-Jakob Disease Evolution after Electroconvulsive Therapy for Catatonic Depression 
Case Reports in Psychiatry  2011;2011:791275.
We describe a case report of an 80-year-old woman who presented with symptomatology compatible with an episode of major depression with catatonia. After psychiatric admission, electroconvulsive therapy (ECT) was applied, but symptoms progressed with cognitive impairment, bradykinesia, widespread stiffness, postural tremor, and gait disturbance. After compatible magnetic resonance imaging (MRI), diffusion changes, and electroencephalogram (EEG) findings the case was reoriented to Creutzfeldt-Jakob disease (CJD). The genetic study found a methionine/valine heterozygosity at codon 129 of the prion protein gene PrPSc. On followup, a significant clinical recovery turned out. For this reason, EEG and MRI were repeated and confirmed the findings. The patient subsequently demonstrated progressive clinical deterioration and died 21 months later. The diagnosis was verified postmortem by neuropathology. The vCJD subtype MV2 is indeed characterized by early and prominent psychiatric symptoms and a prolonged disease duration however no frank clinical recovery has before been reported.
PMCID: PMC3420744  PMID: 22937408
Neurobiology of aging  2008;31(5):725-731.
Mutations in three genes (PSEN1, PSEN2, and APP) have been identified in patients with early-onset (<65years) 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). We found three novel mutations in PSEN1, one novel mutation in PSEN2, and a novel mutation in the APP gene. Four previously described mutations in PSEN1 were also found. The same analysis was carried in 121 elderly healthy controls from the Iberian peninsular, and a set of 130 individuals from seven African populations belonging to the Centre d’Etude du Polymorphisme Humain-Human Genome Diversity Panel (CEPH-HGDP), in order to determine the extent of normal variability in these genes. Interestingly, in the latter series, we found five new nonsynonymous changes in all three genes and a presenilin 2 variant (R62H) that has been previously related to AD. In some of these mutations, the pathologic consequence is uncertain and needs further investigation. To address this question we propose and use a systematic algorithm to classify the putative pathology of AD mutations.
PMCID: PMC2850052  PMID: 18667258
Early-onset Alzheimer’s disease; Presenilins; APP; mutations
6.  Cerebrospinal fluid biomarkers in human genetic transmissible spongiform encephalopathies 
Journal of Neurology  2009;256(10):1620-1628.
The 14-3-3 protein test has been shown to support the clinical diagnosis of sporadic Creutzfeldt-Jakob disease (CJD) when associated with an adequate clinical context, and a high differential potential for the diagnosis of sporadic CJD has been attributed to other cerebrospinal fluid (CSF) proteins such as tau protein, S100b and neuron specific enolase (NSE). So far there has been only limited information available about biochemical markers in genetic transmissible spongiform encephalopathies (gTSE), although they represent 10–15% of human TSEs. In this study, we analyzed CSF of 174 patients with gTSEs for 14-3-3 (n = 166), tau protein (n = 78), S100b (n = 46) and NSE (n = 50). Levels of brain-derived proteins in CSF varied in different forms of gTSE. Biomarkers were found positive in the majority of gCJD (81%) and insert gTSE (69%), while they were negative in most cases of fatal familial insomnia (13%) and Gerstmann-Sträussler-Scheinker syndrome (10%). Disease duration and codon 129 genotype influence the findings in a different way than in sporadic CJD.
PMCID: PMC3085782  PMID: 19444528
Creutzfeldt-Jakob disease; CSF proteins; 14-3-3 protein; Tau

Results 1-6 (6)