[Show abstract][Hide abstract] ABSTRACT: AimsTo assess the sensitivity of the FTDC revised criteria of behavioral variant frontotemporal dementia (bvFTD) in a pathological cohort and to determine their predictive values in a clinical context suggestive of bvFTD. To assess the influence of the age at onset and underlying pathology in the clinico-pathological correlations.Methods
Retrospective, blinded review of the clinical and neuropathological data from the Neurological Tissue Bank (NTB) of the Biobank-Hospital Clinic-IDIBAPS, Barcelona (Spain) assessing the fulfillment of the diagnostic criteria on a case-by-case basis. Two separate nonexclusive cohorts were selected: Cohort 1 (n=58) subjects with pathological diagnosis of frontotemporal lobar degeneration (FTLD) and Cohort 2 (n=66) subjects with the premortem diagnosis of bvFTD.ResultsThe FTDC criteria reached a sensitivity of 93% for possible and 80% for probable bvFTD. Early-onset cases displayed significantly more disinhibition, loss of empathy and compulsive behavior with respect to late-onset bvFTD leading to a slightly higher sensitivity of the diagnostic criteria (97% vs 91%). There were no differences in the diagnostic performance between tau-positive and tau-negative cases. In subjects clinically diagnosed as bvFTD, a “possible bvFTD” diagnosis reached a positive predictive value for FTLD pathology of 90%, irrespective of underlying proteinopathy. False-positive clinical diagnoses were mainly Alzheimer's disease. These cases were significantly older, had less family history of dementia and had a predominantly apathetic clinical picture.Conclusions
The revised bvFTD criteria present good sensitivity and positive predictive value in both early and late-onset cases and regardless of the underlying FTLD pathology.
Neuropathology and Applied Neurobiology 11/2014; · 4.84 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The BrainNet Europe consortium assessed the reproducibility in the assignment of the type of frontotemporal lobar degeneration (FTLD) with TAR DNA-binding protein (TDP) 43 following current recommendations. The agreement rates were influenced by the immunohistochemical (IHC) method and by the classification strategy followed. p62-IHC staining yielded good uniform quality of stains, but the most reliable results were obtained implementing specific Abs directed against the hallmark protein TDP43. Both assessment of the type and the extent of lesions were influenced by the Abs and by the quality of stain. Assessment of the extent of the lesions yielded poor results repeatedly; thus, the extent of pathology should not be used in diagnostic consensus criteria. Whilst 31 neuropathologists typed 30 FTLD-TDP cases, inter-rater agreement ranged from 19 to 100 per cent, being highest when applying phosphorylated TDP43/IHC. The agreement was highest when designating Type C or Type A/B. In contrast, there was a poor agreement when attempting to separate Type A or Type B FTLD-TDP. In conclusion, we can expect that neuropathologist, independent of his/her familiarity with FTLD-TDP pathology, can identify a TDP43-positive FTLD case. The goal should be to state a Type (A, B, C, D) or a mixture of Types (A/B, A/C or B/C). Neuropathologists, other clinicians and researchers should be aware of the pitfalls whilst doing so. Agreement can be reached in an inter-laboratory setting regarding Type C cases with thick and long neurites, whereas the differentiation between Types A and B may be more troublesome.
Journal of Neural Transmission 09/2014; · 2.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: AimsCreutzfeldt-Jakob disease (CJD) is a rapid progressive neurological disease leading to dementia and death. Prion biomarkers are altered in the cerebrospinal fluid (CSF) of CJD patients, but the pathogenic mechanisms underlying these alterations are still unknown. The present study examined prion biomarker levels in the brain and CSF of sporadic CJD (sCJD) cases and their correlation with neuropathological lesion profiles.Methods
The expression levels of 14-3-3, Tau, phospho-Tau and α-synuclein were measured in the CSF and brain of sCJD cases in a subtype- and region-specific manner. In addition, the activity of prion biomarker kinases, the expression levels of CJD hallmarks and the most frequent neuropathological sCJD findings were analysed.ResultsPrion biomarkers levels were increased in the CSF of sCJD patients; however, correlations between mRNA, total protein and their phosphorylated forms in brain were different. The observed downregulation of the main Tau kinase, GSK3, in sCJD brain samples may help to explain the differential phospho-Tau/Tau ratios between sCJD and other dementias in the CSF. Importantly, CSF biomarkers levels do not necessarily correlate with sCJD neuropathological findings.InterpretationPresent findings indicate that prion biomarkers levels in sCJD tissues and their release into the CSF are differentially regulated following specific modulated responses, and suggest a functional role for these proteins in sCJD pathogenesis.
Neuropathology and Applied Neurobiology 08/2014; · 4.84 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Mutations in the gene coding for Sequestosome 1 (SQSTM1) have been genetically associated with amyotrophic lateral sclerosis (ALS) and Paget disease of bone. In the present study, we analyzed the SQSTM1 coding sequence for mutations in an extended cohort of 1,808 patients with frontotemporal lobar degeneration (FTLD), ascertained within the European Early-Onset Dementia consortium. As control dataset, we sequenced 1,625 European control individuals and analyzed whole-exome sequence data of 2,274 German individuals (total n = 3,899). Association of rare SQSTM1 mutations was calculated in a meta-analysis of 4,332 FTLD and 10,240 control alleles. We identified 25 coding variants in FTLD patients of which 10 have not been described. Fifteen mutations were absent in the control individuals (carrier frequency <0.00026) whilst the others were rare in both patients and control individuals. When pooling all variants with a minor allele frequency <0.01, an overall frequency of 3.2 % was calculated in patients. Rare variant association analysis between patients and controls showed no difference over the whole protein, but suggested that rare mutations clustering in the UBA domain of SQSTM1 may influence disease susceptibility by doubling the risk for FTLD (RR = 2.18 [95 % CI 1.24-3.85]; corrected p value = 0.042). Detailed histopathology demonstrated that mutations in SQSTM1 associate with widespread neuronal and glial phospho-TDP-43 pathology. With this study, we provide further evidence for a putative role of rare mutations in SQSTM1 in the genetic etiology of FTLD and showed that, comparable to other FTLD/ALS genes, SQSTM1 mutations are associated with TDP-43 pathology.
[Show abstract][Hide abstract] ABSTRACT: We report a 54-year-old man who was admitted to the hospital because of acute neurological symptoms due to a cerebral haemorrhage. Postmortem brain examination revealed a lobar haemorrhage and advanced AD neuropathologic changes associated with severe cerebral amyloid angiopathy. Genetic study evidenced the presence of a large APP locus duplication (APPdup) in the patient and a PSEN1 p.E318G polymorphism in him and his older asymptomatic sibling. The APPdup spanned 14.5 Mb and blocks of segmental duplications were detected in the breakpoints. We propose the replication-based mechanism of Fork Stalling Template Switching (FoSTeS) to explain this APPdup rearrangement.
[Show abstract][Hide abstract] ABSTRACT: Autoimmunity might be associated with or implicated in sleep and neurodegenerative disorders. We aimed to describe the features of a novel neurological syndrome associated with prominent sleep dysfunction and antibodies to a neuronal antigen.
In this observational study, we used clinical and video polysomnography to identify a novel sleep disorder in three patients referred to the Sleep Unit of Hospital Clinic, University of Barcelona, Spain, for abnormal sleep behaviours and obstructive sleep apnoea. These patients had antibodies against a neuronal surface antigen, which were also present in five additional patients referred to our laboratory for antibody studies. These five patients had been assessed with polysomnography, which was done in our sleep unit in one patient and the recording reviewed in a second patient. Two patients underwent post-mortem brain examination. Immunoprecipitation and mass spectrometry were used to characterise the antigen and develop an assay for antibody testing. Serum or CSF from 298 patients with neurodegenerative, sleep, or autoimmune disorders served as control samples.
All eight patients (five women; median age at disease onset 59 years [range 52-76]) had abnormal sleep movements and behaviours and obstructive sleep apnoea, as confirmed by polysomnography. Six patients had chronic progression with a median duration from symptom onset to death or last visit of 5 years (range 2-12); in four the sleep disorder was the initial and most prominent feature, and in two it was preceded by gait instability followed by dysarthria, dysphagia, ataxia, or chorea. Two patients had a rapid progression with disequilibrium, dysarthria, dysphagia, and central hypoventilation, and died 2 months and 6 months, respectively, after symptom onset. In five of five patients, video polysomnography showed features of obstructive sleep apnoea, stridor, and abnormal sleep architecture (undifferentiated non-rapid-eye-movement [non-REM] sleep or poorly structured stage N2, simple movements and finalistic behaviours, normalisation of non-REM sleep by the end of the night, and, in the four patients with REM sleep recorded, REM sleep behaviour disorder). Four of four patients had HLA-DRB1*1001 and HLA-DQB1*0501 alleles. All patients had antibodies (mainly IgG4) against IgLON5, a neuronal cell adhesion molecule. Only one of the 298 controls, who had progressive supranuclear palsy, had IgLON5 antibodies. Neuropathology showed neuronal loss and extensive deposits of hyperphosphorylated tau mainly involving the tegmentum of the brainstem and hypothalamus in the two patients studied.
IgLON5 antibodies identify a unique non-REM and REM parasomnia with sleep breathing dysfunction and pathological features suggesting a tauopathy.
Fondo de Investigaciones Sanitarias, Centros de Investigación Biomédica en Red de enfermedades neurodegenerativas (CIBERNED) and Respiratorias (CIBERES), Ministerio de Economía y Competitividad, Fundació la Marató TV3, and the National Institutes of Health.
The Lancet Neurology 04/2014; · 21.82 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: 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.
PLoS ONE 02/2014; 9(2):e89741. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Hexanucleotide repeat expansions in chromosome 9 open reading frame 72 (C9orf72) have recently been linked to frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis, and may be the most common genetic cause of both neurodegenerative diseases. Genetic variants at TMEM106B influence risk for the most common neuropathological subtype of FTLD, characterized by inclusions of TAR DNA-binding protein of 43 kDa (FTLD-TDP). Previous reports have shown that TMEM106B is a genetic modifier of FTLD-TDP caused by progranulin (GRN) mutations, with the major (risk) allele of rs1990622 associating with earlier age at onset of disease. Here, we report that rs1990622 genotype affects age at death in a single-site discovery cohort of FTLD patients with C9orf72 expansions (n = 14), with the major allele correlated with later age at death (p = 0.024). We replicate this modifier effect in a 30-site international neuropathological cohort of FTLD-TDP patients with C9orf72 expansions (n = 75), again finding that the major allele associates with later age at death (p = 0.016), as well as later age at onset (p = 0.019). In contrast, TMEM106B genotype does not affect age at onset or death in 241 FTLD-TDP cases negative for GRN mutations or C9orf72 expansions. Thus, TMEM106B is a genetic modifier of FTLD with C9orf72 expansions. Intriguingly, the genotype that confers increased risk for developing FTLD-TDP (major, or T, allele of rs1990622) is associated with later age at onset and death in C9orf72 expansion carriers, providing an example of sign epistasis in human neurodegenerative disease.
[Show abstract][Hide abstract] ABSTRACT: We have compared the protein profiles in plaques and tangles in the hippocampus of post-mortem Alzheimer brains and in opaque and clear regions in the deep cortex of eye lenses of the same donors. From the 7 Alzheimer donors studied, 1 had pronounced bilateral cortical lens opacities, 1 moderate and 5 only minor or no cortical opacities. We focused on beta-sheet levels, a hallmarking property of amyloid-beta, the major protein of plaques and tau protein, the major protein of tangles in Alzheimer brains. Confocal Raman microspectroscopy and imaging was used in combination with hierarchical cluster analysis. Plaques and tangles show high levels of beta-sheets with a beta-sheet to protein ratio of 1.67. This ratio is 1.12 in unaffected brain tissue surrounding the plaques and tangles. In the lenses this ratio is 1.17 independently of the presence or absence of opacities. This major difference in beta-sheet conformation between hippocampus and lens is supported by Congo red and immunostaining of amyloid-beta and tau which were positive for plaques and tangles in the hippocampus but fully negative for the lens irrespective of the presence or absence of opacities. In line with a previous study (Michael et al., 2013) we conclude that cortical lens opacities are not typical for Alzheimer patients and are not hallmarked by accumulation of amyloid-beta, and can thus not be considered as predictors or indicators of Alzheimer disease as claimed by Goldstein et al. (2003).
Experimental Eye Research 12/2013; · 3.02 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Whipplés disease with clinically isolated neurological involvement (CNS-WD) is a rare condition fatal without an early diagnosis.
To present clinical and neuropathological features of three cases of pre- or post-mortem PCR confirmed CNS-WD with distinct clinical presentation, outcome and pathological findings.
One patient had an acute onset with spinal and brainstem involvement and died without CNS-WD diagnosis after fourteen weeks. Neuropathology showed extensive inflammatory and necrotizing lesions with abundant foamy periodic-acid-Schiff (PAS)+ macrophages. The second patient had a subacute evolution with late CNS-WD diagnosis and death occurring 18 months after onset despite antibiotic treatment. Brain examination showed inflammatory lesions in brainstem, thalamus and cerebellum and abundant foamy PAS+ macrophages. The third case was diagnosed within four weeks of onset and treated with an excellent response. He died after a disease-free period of 24 months of unrelated causes. Neuropathology showed cystic residual lesions devoid of microorganisms without inflammatory reaction.
CNS-WD may have an acute or subacute course with variable response to treatment. Accordingly, subjacent lesions may be those of a severe acute necrotizing encephalitic process or subacute inflammatory lesions involving diencephalic, brainstem, cerebellar and spinal regions. Chronic, unspecific residual cavitary brain lesions may be sequelae of a successful treatment. Early diagnosis should allow appropriate treatment and improve prognosis.
[Show abstract][Hide abstract] ABSTRACT: Dementia with Lewy bodies (DLB) is pathologically characterized by α-synuclein aggregates in the brain. Most patients with DLB also show cerebral Alzheimer disease-type pathology (i.e. β-amyloid plaques and hyperphosphorylated tau deposits). It is unclear whether this overlap is coincidental or driven by specific regional or cellular interactions. The aims of this study were to investigate the regional convergence of α-synuclein, tau, and β-amyloid and to identify patterns of cellular co-occurrence of tau and α-synuclein in DLB. The study group consisted of 22 patients who met clinical and neuropathologic criteria for DLB. Protein aggregates were assessed semiquantitatively in 17 brain areas. APOE and MAPT genotypes were determined. Cellular co-occurrence of tau and α-synuclein was evaluated by double immunofluorescence. We found that total β-amyloid pathology scores correlated positively with total α-synuclein pathology scores (ρ = 0.692, p = 0.001). The factors that correlated best with the amount of α-synuclein pathology were the severity of β-amyloid pathology and presence of the MAPT H1 haplotype. Tau and α-synuclein frequently colocalized in limbic areas, but no correlation between total pathology scores was observed. This study confirms and extends the role of β-amyloid deposition and the MAPT H1 haplotype as contributing factors in DLB pathogenesis and demonstrates the confluence of multiple agents in neurodegenerative diseases.
Journal of neuropathology and experimental neurology. 11/2013;
[Show abstract][Hide abstract] ABSTRACT: In Parkinson's disease (PD), cognitive decline and psychiatric symptoms may occur and very often co-exist, eventually leading to PD-dementia. We report three patients with PD who presented striking psychiatric manifestations along with mild cognitive decline not progressing to dementia across the course of disease and in which postmortem neuropathological study revealed, besides alpha-synuclein inmunoreactive Lewy-body pathology, concomitant four-repeat tau positive argyrophilic grain pathology. We consider that argyrophilic grains might have modulated the clinical presentation of PD in these patients, being the main substrate of their prominent psychiatric symptoms in the absence of definite dementia.
Journal of Neurology 09/2013; · 3.84 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Creutzfeldt-Jakob disease (CJD) is a heterogenic neurodegenerative disorder associated with abnormal post-translational processing of cellular prion protein (PrPc). CJD displays distinctive clinical and pathological features which correlate with the genotype at the codon 129 (methionine or valine: M or V respectively)) in the prion protein gene and with size of the protease-resistant core of the abnormal prion protein PrPsc (type 1: 20/21 kDa and type 2: 19 kDa). MM1 and VV2 are the most common sporadic CJD (sCJD) subtypes. PrP mRNA expression levels in the frontal cortex and cerebellum are reduced in sCJD in a form subtype-dependent. Total PrP protein levels and PrPsc levels in the frontal cortex and cerebellum accumulate differentially in sCJD MM1 and sCJD VV2 with no relation between PrPsc deposition and spongiform degeneration and neuron loss, but with microgliosis, and IL6 and TNF-α response. In the CSF, reduced PrPc, the only form present in this compartment, occurs in sCJD MM1 and VV2. PrP mRNA expression is also reduced in the frontal cortex in advanced stages of Alzheimer disease, Lewy body disease, progressive supranuclear palsy and frontotemporal lobe degeneration, but PrPc levels in brain varies from one disease to another. Reduced PrPc levels in CSF correlate with PrP mRNA expression in brain, which in turn reflects severity of degeneration in sCJD.
[Show abstract][Hide abstract] ABSTRACT: To describe an unusual pattern of epithelial membrane antigen (EMA) immunoreactivity in highly proliferative human Bergmann glia.
An immunohistochemical study was performed of postmortem cerebellar tissue from 18 adult patients with cerebellar damage of various aetiologies and 15 biopsies of diverse adult and paediatric cerebellar tumours. We observed marked proliferation of Bergmann glia with unusual prominent dot-like cytoplasmic EMA immunoreactivity in a case with extensive leptomeningeal sarcomatosis. Similar staining was not observed in association with other types of cerebellar pathology, except for other neoplastic conditions, such as leptomeningeal carcinomatosis, adult medulloblastoma, and pilocytic astrocytoma in children. At an ultrastructural level, the index case showed prominent endoplasmic reticulum with some intermediate filaments and lipofuscin granules, but no structures related to cilia or microvilli were observed.
We consider that prominent EMA dots in Bergmann glia might represent excessive activation induced by an overlying leptomeningeal tumour that stimulates the expression of early developmental antigens. This observation suggests modulation of the glial phenotype when exposed to a neoplastic microenvironment that, in turn, might influence the regenerative potential of Bergmann glia.
[Show abstract][Hide abstract] ABSTRACT: Purpose Amyloid beta, the main protein component of Alzheimer (AD) plaques and tangles, is characterized by high levels of beta-sheets. Raman microspectroscopy allows quantitative analysis of this specific molecular conformation. We compared the beta-sheet levels in lens opacities and in plaques and tangles in the hippocampus of AD patients. Methods We obtained 14 lenses from 7 post-mortem donors , neuropathologically confirmed as having advanced or moderate AD. From 3 of these donors, we also obtained hippocampus tissue. Protein and lipid conformations were analysed in the 500-1800 cm-1 fingerprint region. The ratio of the beta-sheet peak at 1668 cm-1 and the protein peak at 1450 cm-1 is a quantitative measure for the beta-sheet content. Additionally, histological sections were stained using a standard Congo red protocol and amyloid beta immunohistochemistry. Results The 1668cm-1/1450cm-1 ratio, quantitatively reflecting the beta-sheet content, is 1.28 for clear and cataractous regions in the lens.For the plaques and tangles in the hippocampus the ratio is 1.62 and 1.23 for non-affected regions. When corrected for the presence of lipids in plaques and tangles this ratio is 2.64. Congo red and amyloid beta immunohistochemistry is positive for AD plaques and tangles but is negative for all lenses studied. Conclusion In contrast with a previous study (Goldstein et al. 2003) we conclude that proteins in opaque regions of lenses and in hippocampal plaques and tangles are fully different species. Moreover opacification is not accompanied by changes in the beta-sheet configuration of lens proteins. This means that cortical cataract cannot be considered as an indicator and predictor of AD.