John Q Trojanowski

William Penn University, Filadelfia, Pennsylvania, United States

Are you John Q Trojanowski?

Claim your profile

Publications (849)7119.27 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Frontotemporal lobar degeneration (FTLD) is one of the leading causes of dementia after Alzheimer’s disease. A high-ranking candidate to become a diagnostic marker for a major pathological subtype of FTLD is the transactive response DNA binding protein of 43 kDa (TDP-43). The main objective is to elucidate which antibodies are specific for pathological TDP-43, with special interest in its modified isoforms. Indeed, TDP-43 has been shown to be hyperphosphorylated and truncated in disease. A secondary objective is to review existing immunoassays that quantify TDP-43 in biofluids. A systematic review of literature was performed by searching PubMed and Web of Science using predefined keywords. Of considered research papers the methods section was reviewed to select publications that enabled us to answer our learning objective. After quality assessment, antibody characteristics and related outcomes were extracted. We identified a series of well-characterized antibodies based on a scoring system that assessed the ability of each antibody to detect TDP-43 pathology. A selection of 29 unique antibodies was made comprising 10 high-ranking antibodies which were reported multiple times to detect TDP-43 pathology in both immunostaining and immunoblotting experiments and 19 additional antibodies which detected TDP-43 pathology but were only scored once. This systematic review provides an overview of antibodies that are reported to detect pathological TDP-43. These antibodies can be used in future studies of TDP-43 proteinopathies. Additionally, selected antibodies hold the potential to be used in the development of novel immunoassays for the quantification of TDP-43 in biofluids, as a possible biomarker for FTLD-TDP.
    12/2015; 3(15). DOI:10.1186/s40478-015-0195-1
  • [Show abstract] [Hide abstract]
    ABSTRACT: Hereditary diffuse leukoencephalopathy with spheroids (HDLS) presents with a variety of clinical phenotypes including motor impairments such as gait dysfunction, rigidity, tremor and bradykinesia as well as cognitive deficits including personality changes and dementia. In recent years, colony stimulating factor 1 receptor gene (CSF1R) has been identified as the primary genetic cause of HDLS. We describe the clinical and neuropathological features in three siblings with HDLS and the CSF1R p.Arg782His (c.2345G > A) pathogenic mutation. Each case had varied motor symptoms and clinical features, but all included slowed movements, poor balance, memory impairment and frontal deficits. Neuroimaging with magnetic resonance imaging revealed atrophy and increased signal in the deep white matter. Abundant white matter spheroids and CD68-positive macrophages were the predominant pathologies in these cases. Similar to other cases reported in the literature, the three cases described here had varied clinical phenotypes with a pronounced, but heterogeneous distribution of axonal spheroids and distinct microglia morphology. Our findings underscore the critical importance of genetic testing for establishing a clinical and pathological diagnosis of HDLS.
    12/2015; 3(1):42. DOI:10.1186/s40478-015-0219-x
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Loss-of-function mutations in the GBA gene are associated with more severe cognitive impairment in PD, but the nature of these deficits is not well understood and whether common GBA polymorphisms influence cognitive performance in PD is not yet known. We screened the GBA coding region for mutations and the E326K polymorphism in 1,369 PD patients enrolled at eight sites from the PD Cognitive Genetics Consortium. Participants underwent assessments of learning and memory (Hopkins Verbal Learning Test-Revised), working memory/executive function (Letter-Number Sequencing Test and Trail Making Test A and B), language processing (semantic and phonemic verbal fluency), visuospatial abilities (Benton Judgment of Line Orientation), and global cognitive function (MoCA). We used linear regression to test for association between genotype and cognitive performance with adjustment for important covariates and accounted for multiple testing using Bonferroni's corrections. Mutation carriers (n = 60; 4.4%) and E326K carriers (n = 65; 4.7%) had a higher prevalence of dementia (mutations, odds ratio = 5.1; P = 9.7 × 10(-6) ; E326K, odds ratio = 6.4; P = 5.7 × 10(-7) ) and lower performance on Letter-Number Sequencing (mutations, corrected P[Pc ] = 9.0 × 10(-4) ; E326K, Pc = 0.036), Trail Making B-A (mutations, Pc = 0.018; E326K, Pc = 0.018), and Benton Judgment of Line Orientation (mutations, Pc = 0.0045; E326K, Pc = 0.0013). Both GBA mutations and E326K are associated with a distinct cognitive profile characterized by greater impairment in working memory/executive function and visuospatial abilities in PD patients. The discovery that E326K negatively impacts cognitive performance approximately doubles the proportion of PD patients we now recognize are at risk for more severe GBA-related cognitive deficits. © 2015 International Parkinson and Movement Disorder Society. © 2015 International Parkinson and Movement Disorder Society.
    Movement Disorders 08/2015; DOI:10.1002/mds.26359 · 5.68 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this work was to describe the development and psychometric analysis of the Penn Parkinson's Daily Activities Questionnaire. The questionnaire is an item response theory-based tool for rating cognitive instrumental activities of daily living in PD. Candidate items for the Penn Parkinson's Daily Activities Questionnaire were developed through literature review and focus groups of patients and knowledgeable informants. Item selection and calibration of item-response theory parameters were performed using responses from a cohort of PD patients and knowledgeable informants (n = 388). In independent cohorts of PD patients and knowledgeable informants, assessments of test-retest reliability (n = 50), and construct validity (n = 68) of the questionnaire were subsequently performed. Construct validity was assessed by correlating questionnaire scores with measures of motor function, cognition, an existing activities of daily living measure, and directly observed daily function. Fifty items were retained in the final questionnaire item bank. Items were excluded owing to redundancy, difficult reading level, and when item-response theory parameters could not be calculated. Test-retest reliability was high (intraclass correlation coefficient = 0.97; P < 0.001). The questionnaire correlated strongly with cognition (r = 0.68; P < 0.001) and directly observed daily function (r = 0.87; P < 0.001), but not with motor impairment (r = 0.08; P = 0.53). The questionnaire score accurately discriminated between PD patients with and without dementia (receiver operating characteristic curve = 0.91; 95% confidence interval: 0.85-0.97). The Penn Parkinson's Daily Activities Questionnaire shows strong evidence of reliability and validity. Item response theory-based psychometric analysis suggests that this questionnaire can discriminate across a range of daily functions. © 2015 International Parkinson and Movement Disorder Society. © 2015 Movement Disorder Society.
    Movement Disorders 08/2015; DOI:10.1002/mds.26339 · 5.68 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Accumulation of phosphorylated cytoplasmic TDP-43 inclusions accompanied by loss of normal nuclear TDP-43 in neurons and glia of the brain and spinal cord are the molecular hallmarks of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD-TDP). However, the role of cytoplasmic TDP-43 in the pathogenesis of these neurodegenerative TDP-43 proteinopathies remains unclear, due in part to a lack of valid mouse models. We therefore generated new mice with doxycycline (Dox)-suppressible expression of human TDP-43 (hTDP-43) harboring a defective nuclear localization signal (∆NLS) under the control of the neurofilament heavy chain promoter. Expression of hTDP-43∆NLS in these 'regulatable NLS' (rNLS) mice resulted in the accumulation of insoluble, phosphorylated cytoplasmic TDP-43 in brain and spinal cord, loss of endogenous nuclear mouse TDP-43 (mTDP-43), brain atrophy, muscle denervation, dramatic motor neuron loss, and progressive motor impairments leading to death. Notably, suppression of hTDP-43∆NLS expression by return of Dox to rNLS mice after disease onset caused a dramatic decrease in phosphorylated TDP-43 pathology, an increase in nuclear mTDP-43 to control levels, and the prevention of further motor neuron loss. rNLS mice back on Dox also showed a significant increase in muscle innervation, a rescue of motor impairments, and a dramatic extension of lifespan. Thus, the rNLS mice are new TDP-43 mouse models that delineate the timeline of pathology development, muscle denervation and neuron loss in ALS/FTLD-TDP. Importantly, even after neurodegeneration and onset of motor dysfunction, removal of cytoplasmic TDP-43 and the concomitant return of nuclear TDP-43 led to neuron preservation, muscle re-innervation and functional recovery.
    Acta Neuropathologica 07/2015; DOI:10.1007/s00401-015-1460-x · 10.76 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Filamentous tau inclusions are hallmarks of Alzheimer's disease (AD) and other neurodegenerative tauopathies. An increasing number of studies implicate the cell-to-cell propagation of tau pathology in the progression of tauopathies. We recently showed (Iba et al., J Neurosci 33:1024-1037, 2013) that inoculation of preformed synthetic tau fibrils (tau PFFs) into the hippocampus of young transgenic (Tg) mice (PS19) overexpressing human P301S mutant tau induced robust tau pathology in anatomically connected brain regions including the locus coeruleus (LC). Since Braak and colleagues hypothesized that the LC is the first brain structure to develop tau lesions and since LC has widespread connections throughout the CNS, LC neurons could be the critical initiators of the stereotypical spreading of tau pathology through connectome-dependent transmission of pathological tau in AD. Here, we report that injections of tau PFFs into the LC of PS19 mice induced propagation of tau pathology to major afferents and efferents of the LC. Notably, tau pathology propagated along LC efferent projections was localized not only to axon terminals but also to neuronal perikarya, suggesting transneuronal transfer of templated tau pathology to neurons receiving LC projections. Further, brainstem neurons giving rise to major LC afferents also developed perikaryal tau pathology. Surprisingly, while tangle-bearing neurons degenerated in the LC ipsilateral to the injection site starting 6 months post-injection, no neuron loss was seen in the contralateral LC wherein tangle-bearing neurons gradually cleared tau pathology by 6-12 months post-injection. However, the spreading pattern of tau pathology observed in our LC-injected mice is different from that in AD brains since hippocampus and entorhinal cortex, which are affected in early stages of AD, were largely spared of tau inclusions in our model. Thus, while our study tested critical aspects of the Braak hypothesis of tau pathology spread, this novel mouse model provides unique opportunities to elucidate mechanisms underlying the selective vulnerability of neurons to acquire tau pathology and succumb to or resist tau-mediated neurodegeneration.
    Acta Neuropathologica 07/2015; DOI:10.1007/s00401-015-1458-4 · 10.76 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Diagnosing behavioral variant frontotemporal dementia (bvFTD) in patients with prior history of stroke or with silent brain infarcts on neuroimaging studies can be challenging. Vascular changes in patients with bvFTD are not unusual, but bvFTD tends to be ruled out in the presence of cerebrovascular disease. We aimed to identify the clinical, cognitive, and risk factor profile of bvFTD with coexistent cerebrovascular disease (V-bvFTD). We compared demographic data, clinical diagnoses, vascular risk factors, functional status, and normalized neuropsychological z-scores between patients with V-bvFTD vs. bvFTD without concomitant cerebrovascular disease (NV-bvFTD) from the National Alzheimer's Coordinating Centre database. We included 391 neuropathologically diagnosed cases of frontotemporal lobe degeneration (FTLD). We excluded patients that were diagnosed with aphasic variants of frontotemporal dementia before death. Patients with V-bvFTD (n=62) were older at the time of onset of cognitive decline (71.6 vs. 62.5years, p<0.001) and death (78.7 vs. 69.6, p<0.001), more likely to be hypertensive (75.8 vs. 45.7%, p=0.002), and to have a history of stroke (21.2 vs. 6.1%, p=0.007) than those with NV-bvFTD (n=329). V-bvFTD was often underdiagnosed, affected elderly patients, and had a similar cognitive profile as NV-bvFTD despite the presence of brain infarcts. In the whole cohort, we observed enhanced cognitive performance with increasing age quintiles despite larger proportions of cerebrovascular disease pathology, likely meaning that FTLD-related primary neurodegeneration exerts a stronger impact on cognition than cerebrovascular disease. Coexisting cerebrovascular disease should not preclude the diagnosis of bvFTD.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We describe Alzheimer's Disease Neuroimaging Initiative (ADNI) Biomarker Core progress including: the Biobank; cerebrospinal fluid (CSF) amyloid beta (Aβ1-42), t-tau, and p-tau181 analytical performance, definition of Alzheimer's disease (AD) profile for plaque, and tangle burden detection and increased risk for progression to AD; AD disease heterogeneity; progress in standardization; and new studies using ADNI biofluids. Review publications authored or coauthored by ADNI Biomarker core faculty and selected non-ADNI studies to deepen the understanding and interpretation of CSF Aβ1-42, t-tau, and p-tau181 data. CSF AD biomarker measurements with the qualified AlzBio3 immunoassay detects neuropathologic AD hallmarks in preclinical and prodromal disease stages, based on CSF studies in non-ADNI living subjects followed by the autopsy confirmation of AD. Collaboration across ADNI cores generated the temporal ordering model of AD biomarkers varying across individuals because of genetic/environmental factors that increase/decrease resilience to AD pathologies. Further studies will refine this model and enable the use of biomarkers studied in ADNI clinically and in disease-modifying therapeutic trials. Copyright © 2015. Published by Elsevier Inc.
    Alzheimer's & dementia: the journal of the Alzheimer's Association 07/2015; 11(7):772-91. DOI:10.1016/j.jalz.2015.05.003 · 17.47 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The Alzheimer's Disease Neuroimaging Initiative (ADNI) was established in 2004 to facilitate the development of effective treatments for Alzheimer's disease (AD) by validating biomarkers for AD clinical trials. We searched for ADNI publications using established methods. ADNI has (1) developed standardized biomarkers for use in clinical trial subject selection and as surrogate outcome measures; (2) standardized protocols for use across multiple centers; (3) initiated worldwide ADNI; (4) inspired initiatives investigating traumatic brain injury and post-traumatic stress disorder in military populations, and depression, respectively, as an AD risk factor; (5) acted as a data-sharing model; (6) generated data used in over 600 publications, leading to the identification of novel AD risk alleles, and an understanding of the relationship between biomarkers and AD progression; and (7) inspired other public-private partnerships developing biomarkers for Parkinson's disease and multiple sclerosis. ADNI has made myriad impacts in its first decade. A competitive renewal of the project in 2015 would see the use of newly developed tau imaging ligands, and the continued development of recruitment strategies and outcome measures for clinical trials. Copyright © 2015 The Alzheimer's Association. All rights reserved.
    Alzheimer's & dementia: the journal of the Alzheimer's Association 07/2015; 11(7):865-84. DOI:10.1016/j.jalz.2015.04.005 · 17.47 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Previous studies demonstrate that intrastriatal injections of fibrillar alpha-synuclein (α-syn) into mice induce Parkinson's disease (PD)-like Lewy body (LB) pathology formed by aggregated α-syn in anatomically interconnected regions and significant nigrostriatal degeneration. The aim of the current study was to evaluate whether exogenous mouse α-syn pre-formed fibrils (PFF) injected into the striatum of rats would result in accumulation of LB-like intracellular inclusions and nigrostriatal degeneration. Sprague Dawley rats received unilateral intrastriatal injections of either non-fibrillized recombinant α-syn or PFF mouse α-syn in 1- or 2- sites and were euthanized at 30, 60 or 180 days post-injection (pi). Both non-fibrillized recombinant α-syn and PFF α-syn injections resulted in phosphorylated α-syn intraneuronal accumulations (i.e., diffuse Lewy neurite (LN)- and LB-like inclusions) with significantly greater accumulations following PFF injection. LB-like inclusions were observed in several areas that innervate the striatum, most prominently the frontal and insular cortices, the amygdala, and the substantia nigra pars compacta (SNpc). α-Syn accumulations co-localized with ubiquitin, p62, and were thioflavin-S-positive and proteinase-k resistant, suggesting PFF-induced pathology exhibits properties similar to human LBs. Although α-syn inclusions within the SNpc remained ipsilateral to striatal injection, we observed bilateral reductions in nigral dopamine neurons at the 180-day time point in both the 1- and 2-site PFF injection paradigms. PFF injected rats exhibited bilateral reductions in striatal dopaminergic innervation at 60 and 180 days and bilateral decreases in homovanillic acid; however, dopamine reduction was observed only in the striatum ipsilateral to PFF injection. Although the level of dopamine asymmetry in PFF injected rats at 180 days was insufficient to elicit motor deficits in amphetamine-induced rotations or forelimb use in the cylinder task, significant disruption of ultrasonic vocalizations was observed. Taken together, our findings demonstrate that α-syn PFF are sufficient to seed the pathological conversion and propagation of endogenous α-syn to induce a progressive, neurodegenerative model of α-synucleinopathy in rats. Copyright © 2015. Published by Elsevier Inc.
    Neurobiology of Disease 06/2015; 82. DOI:10.1016/j.nbd.2015.06.003 · 5.20 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We studied the biomarker signatures and prognoses of 3 different subtle cognitive impairment (SCI) groups (executive, memory, and multidomain) as well as the subjective memory complaints (SMC) group. We studied 522 healthy controls in the Alzheimer's Disease Neuroimaging Initiative (ADNI). Cutoffs for executive, memory, and multidomain SCI were defined using participants who remained cognitively normal (CN) for 7 years. CSF Alzheimer disease (AD) biomarkers, composite and region-of-interest (ROI) MRI, and fluorodeoxyglucose-PET measures were compared in these participants. Using a stringent cutoff (fifth percentile), 27.6% of the ADNI participants were classified as SCI. Most single ROI or global-based measures were not sensitive to detect differences between groups. Only MRI-SPARE-AD (Spatial Pattern of Abnormalities for Recognition of Early AD), a quantitative MRI pattern-based global index, showed differences between all groups, excluding the executive SCI group. Atrophy patterns differed in memory SCI and SMC. The CN and the SMC groups presented a similar distribution of preclinical dementia stages. Fifty percent of the participants with executive, memory, and multidomain SCI progressed to mild cognitive impairment or dementia at 7, 5, and 2 years, respectively. Our results indicate that (1) the different SCI categories have different clinical prognoses and biomarker signatures, (2) longitudinally followed CN subjects are needed to establish clinical cutoffs, (3) subjects with SMC show a frontal pattern of brain atrophy, and (4) pattern-based analyses outperform commonly used single ROI-based neuroimaging biomarkers and are needed to detect initial stages of cognitive impairment. © 2015 American Academy of Neurology.
    Neurology 06/2015; DOI:10.1212/WNL.0000000000001738 · 8.30 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Corticobasal degeneration (CBD) is a neurodegenerative disorder affecting movement and cognition, definitively diagnosed only at autopsy. Here, we conduct a genome-wide association study (GWAS) in CBD cases (n=152) and 3,311 controls, and 67 CBD cases and 439 controls in a replication stage. Associations with meta-analysis were 17q21 at MAPT (P=1.42 × 10(-12)), 8p12 at lnc-KIF13B-1, a long non-coding RNA (rs643472; P=3.41 × 10(-8)), and 2p22 at SOS1 (rs963731; P=1.76 × 10(-7)). Testing for association of CBD with top progressive supranuclear palsy (PSP) GWAS single-nucleotide polymorphisms (SNPs) identified associations at MOBP (3p22; rs1768208; P=2.07 × 10(-7)) and MAPT H1c (17q21; rs242557; P=7.91 × 10(-6)). We previously reported SNP/transcript level associations with rs8070723/MAPT, rs242557/MAPT, and rs1768208/MOBP and herein identified association with rs963731/SOS1. We identify new CBD susceptibility loci and show that CBD and PSP share a genetic risk factor other than MAPT at 3p22 MOBP (myelin-associated oligodendrocyte basic protein).
    Nature Communications 06/2015; 6. DOI:10.1038/ncomms8247 · 10.74 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Apathy is a common, troublesome symptom in Parkinson's disease (PD). However, little is known about its relationship with long-term cognition. We sought to determine if a caregiver-reported apathy measure predicts the development of PD dementia. Non-demented PD patients were recruited as part of a longitudinal study of cognition. Demographics, medications, Dementia Rating Scale-2, Unified Parkinson's Disease Rating Scale, Geriatric Depression Scale and the Neuropsychiatric Inventory-Questionnaire (NPI-Q) ratings were obtained. Apathy was defined as an NPI-Q apathy score ≥1. Participants were evaluated annually with cognitive and functional assessments until the end of the study period or a physician consensus diagnosis of dementia was assigned. Cox proportional hazard models were used to assess the effects of baseline apathy on dementia development while controlling for other clinical and demographic factors. Of 132 PD patients 12.1% (N = 16) scored in the apathetic range at baseline. A total of 19.6% (N = 26) individuals developed dementia over the course of the study, 8 of whom (30.8% of future dementia patients) had baseline apathy. In bivariate analyses baseline apathy, older age, and worse cognitive, motor, and depressive symptom scores predicted the development of dementia. In a multivariate analysis the predictive effects of baseline apathy were still significant (HR = 3.56; 95% CI = 1.09-11.62; p = 0.04). A simple, caregiver-reported measure of apathy is an independent predictor of progression to dementia in PD. This highlights the importance of apathy as a clinical characteristic of PD and could prove useful for the prediction of future dementia. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Parkinsonism & Related Disorders 06/2015; 21(8). DOI:10.1016/j.parkreldis.2015.06.009 · 4.13 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Introduction Accumulation of insoluble conformationally altered hyperphosphorylated tau occurs as part of the pathogenic process in Alzheimer’s disease (AD) and other tauopathies. In most AD subjects, wild-type (WT) tau aggregates and accumulates in neurofibrillary tangles and dystrophic neurites in the brain; however, in some familial tauopathy disorders, mutations in the gene encoding tau cause disease. Results We generated a mouse model, Tau4RTg2652, that expresses high levels of normal human tau in neurons resulting in the early stages of tau pathology. In this model, over expression of WT human tau drives pre-tangle pathology in young mice resulting in behavioral deficits. These changes occur at a relatively young age and recapitulate early pre-tangle stages of tau pathology associated with AD and mild cognitive impairment. Several features distinguish the Tau4RTg2652 model of tauopathy from previously described tau transgenic mice. Unlike other mouse models where behavioral and neuropathologic changes are induced by transgenic tau harboring MAPT mutations pathogenic for frontotemporal lobar degeneration (FTLD), the mice described here express the normal tau sequence. Conclusions Features of Tau4RTg2652 mice distinguishing them from other established wild type tau overexpressing mice include very early phenotypic manifestations, non-progressive tau pathology, abundant pre-tangle and phosphorylated tau, sparse oligomeric tau species, undetectable fibrillar tau pathology, stability of tau transgene copy number/expression, and normal lifespan. These results suggest that Tau4RTg2652 animals may facilitate studies of tauopathy target engagement where WT tau is driving tauopathy phenotypes. Electronic supplementary material The online version of this article (doi:10.1186/s40478-015-0210-6) contains supplementary material, which is available to authorized users.
    06/2015; 3(1). DOI:10.1186/s40478-015-0210-6
  • [Show abstract] [Hide abstract]
    ABSTRACT: We investigated whether chromosome 9 open reading frame 72 hexanucleotide repeat expansion (C9orf72 expansion) size in peripheral DNA was associated with clinical differences in frontotemporal degeneration (FTD) and amyotrophic lateral sclerosis (ALS) linked to C9orf72 repeat expansion mutations. A novel quantification workflow was developed to measure C9orf72 expansion size by Southern blot densitometry in a cross-sectional cohort of C9orf72 expansion carriers with FTD (n = 39), ALS (n = 33), both (n = 35), or who are unaffected (n = 21). Multivariate linear regressions were performed to assess whether C9orf72 expansion size from peripheral DNA was associated with clinical phenotype, age of disease onset, disease duration and age at death. Mode values of C9orf72 expansion size were significantly shorter in FTD compared to ALS (p = 0.0001) but were not associated with age at onset in either FTD or ALS. A multivariate regression model correcting for patient's age at DNA collection and disease phenotype revealed that C9orf72 expansion size is significantly associated with shorter disease duration (p = 0.0107) for individuals with FTD, but not with ALS. Despite considerable somatic instability of the C9orf72 expansion, semi-automated expansion size measurements demonstrated an inverse relationship between C9orf72 expansion size and disease duration in patients with FTD. Our finding suggests that C9orf72 repeat size may be a molecular disease modifier in FTD linked to hexanucleotide repeat expansion.
    Acta Neuropathologica 05/2015; DOI:10.1007/s00401-015-1445-9 · 10.76 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This study assessed apolipoprotein E (APOE) ε4 carrier status effects on Alzheimer's disease imaging and cerebrospinal fluid (CSF) biomarkers in cognitively normal older adults with significant memory concerns (SMC). Cognitively normal, SMC, and early mild cognitive impairment participants from Alzheimer's Disease Neuroimaging Initiative were divided by APOE ε4 carrier status. Diagnostic and APOE effects were evaluated with emphasis on SMC. Additional analyses in SMC evaluated the effect of the interaction between APOE and [(18)F]Florbetapir amyloid positivity on CSF biomarkers. SMC ε4+ showed greater amyloid deposition than SMC ε4-, but no hypometabolism or medial temporal lobe (MTL) atrophy. SMC ε4+ showed lower amyloid beta 1-42 and higher tau/p-tau than ε4-, which was most abnormal in APOE ε4+ and cerebral amyloid positive SMC. SMC APOE ε4+ show abnormal changes in amyloid and tau biomarkers, but no hypometabolism or MTL neurodegeneration, reflecting the at-risk nature of the SMC group and the importance of APOE in mediating this risk. Copyright © 2015 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.
    Alzheimer's & dementia: the journal of the Alzheimer's Association 05/2015; DOI:10.1016/j.jalz.2015.03.003 · 17.47 Impact Factor
  • Source
    PLoS ONE 05/2015; 10(5):e0125614. DOI:10.1371/journal.pone.0125614 · 3.23 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Glucocerebrosidase gene (GBA) variants that cause Gaucher disease are associated with Parkinson disease (PD) and dementia with Lewy bodies (DLB). To investigate the role of GBA variants in multiple system atrophy (MSA), we analyzed GBA variants in a large case-control series. We sequenced coding regions and flanking splice sites of GBA in 969 MSA patients (574 Japanese, 223 European, and 172 North American) and 1509 control subjects (900 Japanese, 315 European, and 294 North American). We focused solely on Gaucher-disease-causing GBA variants. In the Japanese series, we found nine carriers among the MSA patients (1.65%) and eight carriers among the control subjects (0.89%). In the European series, we found three carriers among the MSA patients (1.35%) and two carriers among the control subjects (0.63%). In the North American series, we found five carriers among the MSA patients (2.91%) and one carrier among the control subjects (0.34%). Subjecting each series to a Mantel-Haenszel analysis yielded a pooled odds ratio (OR) of 2.44 (95% confidence interval [CI], 1.14-5.21) and a P-value of 0.029 without evidence of significant heterogeneity. Logistic regression analysis yielded similar results, with an adjusted OR of 2.43 (95% CI 1.15-5.37) and a P-value of 0.022. Subtype analysis showed that Gaucher-disease-causing GBA variants are significantly associated with MSA cerebellar subtype (MSA-C) patients (P = 7.3 × 10(-3)). The findings indicate that, as in PD and DLB, Gaucher-disease-causing GBA variants are associated with MSA.
    04/2015; 2(4):417-26. DOI:10.1002/acn3.185
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cerebrospinal fluid (CSF) and positron emission tomographic (PET) amyloid biomarkers have been proposed for the detection of Alzheimer disease (AD) pathology in living patients and for the tracking of longitudinal changes, but the relation between biomarkers needs further study. To determine the association between CSF and PET amyloid biomarkers (cross-sectional and longitudinal measures) and compare the cutoffs for these measures. Longitudinal clinical cohort study from 2005 to 2014 including 820 participants with at least 1 florbetapir F-18 (hereafter referred to as simply florbetapir)-PET scan and at least 1 CSF β-amyloid 1-42 (Aβ1-42) sample obtained within 30 days of each other (501 participants had a second PET scan after 2 years, including 150 participants with CSF Aβ1-42 measurements). Data were obtained from the Alzheimer's Disease Neuroimaging Initiative database. Four different PET scans processing pipelines from 2 different laboratories were compared. The PET cutoff values were established using a mixture-modeling approach, and different mathematical models were applied to define the association between CSF and PET amyloid measures. The values of the CSF Aβ1-42 samples and florbetapir-PET scans showed a nonlinear association (R2 = 0.48-0.66), with the strongest association for values in the middle range. The presence of a larger dynamic range of florbetapir-PET scan values in the higher range compared with the CSF Aβ1-42 plateau explained the differences in correlation with cognition (R2 = 0.36 and R2 = 0.25, respectively). The APOE genotype significantly modified the association between both biomarkers. The PET cutoff values derived from an unsupervised classifier converged with previous PET cutoff values and the established CSF Aβ1-42 cutoff levels. There was no association between longitudinal Aβ1-42 levels and standardized uptake value ratios during follow-up. The association between both biomarkers is limited to a middle range of values, is modified by the APOE genotype, and is absent for longitudinal changes; 4 different approaches in 2 different platforms converge on similar pathological Aβ cutoff levels; and different pipelines to process PET scans showed correlated but not identical results. Our findings suggest that both biomarkers measure different aspects of AD Aβ pathology.
    03/2015; 72(5). DOI:10.1001/jamaneurol.2014.4829
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The relationship between primary age-related tauopathy (PART) and Alzheimer’s disease (AD) is currently a matter of discussion. Recently the term PART was referred to cases characterized by mainly allocortical neurofibrillary (NF) pathology (Braak stages 0-IV) with only few or no amyloid (Aβ) deposits (Thal Aβ phases 0-2) [49]. In addition, no elevated soluble Aβ was detected in this disorder [9, 46]. PART cases that lack any Aβ do not meet formal criteria for sporadic AD according to the NIA-AA guidelines [35]. These neurofibrillary tangle (NFT)+/Aβ-brains are commonly observed in extreme old age [9, 15, 19]. When associated with a high density of NFTs in the same distribution and some cognitive deficits, the disorder has been referred to as tangle-predominant senile dementia (TPSD) [27] or “tangle-only dementia” [55].The new neuropathologic criteria recommend subdividing PART cases into “definite” (Braak stage ≤IV, Thal Aβ phase 0) and “possible” (Braak stage ≤IV, Thal Aβ phase 1-2) ...
    Acta Neuropathologica 03/2015; 129(5). DOI:10.1007/s00401-015-1407-2 · 10.76 Impact Factor

Publication Stats

58k Citations
7,119.27 Total Impact Points

Institutions

  • 1992–2015
    • William Penn University
      • Biology
      Filadelfia, Pennsylvania, United States
  • 1985–2015
    • University of Pennsylvania
      • • Center for Neurodegenerative Disease Research
      • • Department of Pathology and Laboratory Medicine
      • • Department of Neurology
      • • Department of Pathology
      • • Department of Neurosurgery
      • • Department of Psychiatry
      • • Department of Medicine
      Filadelfia, Pennsylvania, United States
  • 2014
    • University of Tuebingen
      • Department of Psychiatry and Psychotherapy
      Tübingen, Baden-Württemberg, Germany
  • 2012
    • Harvard Medical School
      Boston, Massachusetts, United States
  • 2010–2012
    • University of Washington Seattle
      • • Department of Pathology
      • • Department of Medicine
      Seattle, WA, United States
    • Mayo Clinic - Rochester
      • Department of Radiology
      Рочестер, Minnesota, United States
  • 2009
    • Monell Chemical Senses Center
      Philadelphia, Pennsylvania, United States
  • 2004–2009
    • University of California, San Francisco
      San Francisco, California, United States
    • Drexel University
      Filadelfia, Pennsylvania, United States
  • 2008
    • Robarts Research Institute
      London, Ontario, Canada
  • 2007
    • Carl von Ossietzky Universität Oldenburg
      Oldenburg, Lower Saxony, Germany
    • University of Oklahoma Health Sciences Center
      Oklahoma City, Oklahoma, United States
    • Ludwig-Maximilian-University of Munich
      • Center for Neuropathology and Prion Research
      München, Bavaria, Germany
    • Treatment Research Institute, Philadelphia PA
      Philadelphia, Pennsylvania, United States
  • 2005–2006
    • National Institute on Aging
      Baltimore, Maryland, United States
    • In Silico Biosciences, Inc.
      Lexington, Massachusetts, United States
  • 1990–2006
    • The Children's Hospital of Philadelphia
      • Department of Pathology and Laboratory Medicine
      Philadelphia, PA, United States
  • 2003
    • Johns Hopkins University
      Baltimore, Maryland, United States
  • 2002
    • University of Pittsburgh
      Pittsburgh, Pennsylvania, United States
    • Goethe-Universität Frankfurt am Main
      Frankfurt, Hesse, Germany
  • 2001
    • Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico
      • Neurorianimazione
      Milano, Lombardy, Italy
  • 1998
    • McGill University
      • Department of Neurology and Neurosurgery
      Montréal, Quebec, Canada
  • 1996–1998
    • Hospital of the University of Pennsylvania
      • Department of Pathology and Laboratory Medicine
      Filadelfia, Pennsylvania, United States
  • 1997
    • Washington University in St. Louis
      • Department of Neurology
      San Luis, Missouri, United States
  • 1995
    • University of Groningen
      Groningen, Groningen, Netherlands
  • 1994
    • The Philadelphia Center
      Philadelphia, Pennsylvania, United States
  • 1985–1991
    • Duke University Medical Center
      • • Department of Pathology
      • • Department of Pediatrics
      Durham, NC, United States