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Objective: The predictive value of electrophysiologic visual testing in Creutzfeldt-Jakob disease (CJD) was investigated, and the retinal pathologic findings in three cases are reported.Background: The fatal prognosis of CJD, its transmissibility, and the lack of treatment make early diagnosis essential in averting human-to-human transmission. Electroretinogram and visual evoked potentials have been studied in few cases of CJD.Methods: A visual electrophysiologic examination was performed in 41 consecutive patients referred with suspected CJD. The disease had been diagnosed in 24 patients (CJD group; 15 were confirmed neuropathologically and 9 by clinicolaboratory methods in accordance with diagnostic criteria). The remaining 17 patients were diagnosed with other neurologic disorders, and served as a control group.Results: Flash electroretinogram revealed a significant decrease in the amplitude of the B1 wave (10 µV) in the CJD group, especially in patients with myoclonus.Conclusions: The visual electrophysiologic abnormalities provide an interesting noninvasive diagnostic tool in idiopathic CJD. The B1-wave decrease is closely correlated with the outer plexiform layer abnormalities observed on neuropathologic examination.

Summary Uncertainties in the clinical and pathological definition of vascular dementia (VaD) have impeded the development of valid epidemiological studies. VaD occurs in the same age category than Alzheimer's disease (AD) and Alzheimer pathology is found in up to 20 % of patients with VaD. The most currently used criteria for VaD are those summarized by the National Institute of Neruological Disorders and Stroke and the “Association Internationale pour la Recerche et l'Enseignement en Neursciences” (NINDS-AIREN): they require criteria for dementia, clinical or radiological evidence for a vascular pathology of the brain, and a temporal relationship between both. Descriptive epidemiological studies usually include VaD of any type. Small subcortical infarcts account for one sixth of all ischemic strokes, but this proportion is probably higher in patients with VaD. The sex-specific prevalence rates of VaD over the age of 60 in Europe is 2.6 % for men and 2.1 % for women. The prevalence increases steeply with age, but patients with AD and coincidental vascular lesions of the brain are often included. The incidence rate of VaD increases approximately from 20/100.000 between 60 and 69 years to 700/100.000 over 80. There was an overall decline in incidence of VaD over the last 2 decades. The incidence of new-onset dementia is increased after an ischemic stroke. However, VaD probably accounts for only half of dementia occurring after stroke. Approximately one sixth of stroke patients have pre-existing dementia. Subcortical VaD are due to subcortical infarcts, leukoencephalopathies or both. Subcortical infarcts are likely to be the cause of dementia in (i) strategic subcortical (e.g., thalamic) infarcts with previous normal cognitive functioning; (ii) lacunar state; and (iii) cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). The first 2 types are usually the consequence of lipohyalinosis of the small perforating arteries; their main risk factor is arterial hypertension. CADASIL is an autosomal dominant inherited disorder. White matter abnormalities are often associated with risk factors for stroke such as age, arterial hypertension, cardiac diseases and diabetes mellitus. The main risk factor of subcortical VaD is arterial hypertension. Further studies should now determine whether its treatment can reduce the risk of subcortical VaD.

While semantic memory deficits are a common landmark of Alzheimer's disease, the nature of these impairments remains to be clarified. Implicit tasks which assess semantic priming effects are often used to understand semantic deficits in Alzheimer's disease, but they have led to unclear conclusions because of methodological problems such as intervention of attentional mechanisms. To explore the effects of semantic priming in Alzheimer's disease and their relationship with semantic memory deficits, we used two tasks, one implicit and the other explicit. The implicit task was a lexical decision task to assess semantic priming, and in which pairs of words had coordinate (tiger-lion) or attribute relationships (zebra-stripe). The explicit task was a semantic knowledge task composed of namings and questions involving superordinate categories and attribute knowledge of concepts. The two tasks systematically assessed the integrity of the same concepts. This protocol was given to 53 Alzheimer's disease patients with mild to moderate dementia and to 20 controls. The Alzheimer's disease group as a whole obtained significantly greater priming effects (hyperpriming) than controls in the coordinate condition, and equivalent priming in the attribute condition. In the coordinate condition, a subgroup of 26 patients, with attribute knowledge deficits, had larger priming effects than both a subgroup without semantic deficits and the control group. These results show that in Alzheimer's disease the semantic priming effects vary according to the degree of attribute loss, and the presence of hyperpriming would reflect semantic memory deficits. This study unravels the fine-grained structure of semantic memory disturbances in Alzheimer's disease with mild to moderate dementia, affecting initially the attributes of concepts within a hierarchical network in which superordinate concepts remain preserved.

International audience; The aim of this study was to establish the frequency of ATXN2 polyglutamine (polyQ) expansion in large cohorts of patients with amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and progressive supranuclear palsy (PSP), and to evaluate whether ATXN2 could act as a modifier gene in patients carrying the C9orf72 expansion. We screened a large cohort of French patients (1,144 ALS, 203 FTD, 168 FTD-ALS, and 109 PSP) for ATXN2 CAG repeat length. We included in our cohort 322 carriers of the C9orf72 expansion (202 ALS, 63 FTD, and 57 FTD-ALS). We found a significant association with intermediate repeat size (≥29 CAG) in patients with ALS (both familial and sporadic) and, for the first time, in patients with familial FTD-ALS. Of interest, we found the co-occurrence of pathogenic C9orf72 expansion in 23.2% of ATXN2 intermediate-repeat carriers, all in the FTD-ALS and familial ALS subgroups. In the cohort of C9orf72 carriers, 3.1% of patients also carried an intermediate ATXN2 repeat length. ATXN2 repeat lengths in patients with PSP and FTD were found to be similar to the controls. ATXN2 intermediary repeat length is a strong risk factor for ALS and FTD-ALS. Furthermore, we propose that ATXN2 polyQ expansions could act as a strong modifier of the FTD phenotype in the presence of a C9orf72 repeat expansion, leading to the development of clinical signs featuring both FTD and ALS.

Annual Meeting of the Society-of-Nuclear-Medicine-and-Molecular-Imaging (SNMMI), Denver, CO, JUN 10-14, 2017; International audience

Objective: To determine whether the effects of APOE promoter polymorphisms on AD are independent of the APOE -e4 allele. Background: Recently, the −491 A→T and −219 G→T polymorphisms located in the APOE promoter have been suggested to be risk factors for AD. However, the effects of these polymorphisms have not always been reproduced in case-control studies, possibly because of the strong linkage disequilibrium existing at this locus or the characteristics of the populations studied. Methods: Data collection was performed from six independent samples (1,732 patients with AD and 1,926 control subjects) genotyped for APOE exon 4 and the two APOE promoter polymorphisms. The risks associated with the APOE polymorphisms for developing AD were estimated using logistic regression procedures and calculation of odds ratios with 95% CI adjusted by age, sex, and collection center. Independence of the APOE promoter polymorphisms was tested by stratification for APOE -e4 and tertile design was used for age stratification. Results: The independence of the −491 AA genotype was observed in the whole sample whereas the independence of the −219 TT genotype was observed only in the oldest population. Conclusion: The −491 and −219 APOE promoter polymorphisms incur risk for AD in addition to risk associated with the APOE -e4 allele, with age accentuating the effect of the −219 TT genotype. Because these polymorphisms appear to influence apoE levels, these results suggest that APOE expression is an important determinant of AD pathogenesis.

Introduction The cerebrospinal fluid (CSF) biomarkers amyloid-β (Aβ), tau and phosphorylated tau (p-tau181) are now used for the diagnosis of Alzheimer’s disease (AD). Aβ40 is the most abundant Aβ peptide isoform in the CSF, and the Aβ 42/40 ratio has been proposed to better reflect brain amyloid production. However, its additional value in the clinical setting remains uncertain. Methods A total of 367 subjects with cognitive disorders who underwent a lumbar puncture were prospectively included at three French memory centers (Paris-North, Lille and Montpellier; the PLM Study). The frequency of positive, negative and indeterminate CSF profiles were assessed by various methods, and their adequacies with the diagnosis of clinicians were tested using net reclassification improvement (NRI) analyses. Results On the basis of local optimum cutoffs for Aβ42 and p-tau181, 22% of the explored patients had indeterminate CSF profiles. The systematic use of Aβ 42/40 ratio instead of Aβ42 levels alone decreased the number of indeterminate profiles (17%; P = 0.03), but it failed to improve the classification of subjects (NRI = −2.1%; P = 0.64). In contrast, the use of Aβ 42/40 ratio instead of Aβ42 levels alone in patients with a discrepancy between p-tau181 and Aβ42 led to a reduction by half of the number of indeterminate profiles (10%; P

Objective:To determine frequency, determinants, and time course of poststroke depressive symptoms (DS) and their relationship with dementia.Methods:Two hundred two consecutive stroke patients were prospectively evaluated for DS, followed up over a 3-year period. Patients with Montgomery and Asberg Depression Rating Scale (MADRS) scores of ≥7 were considered as having DS. The severity of the neurologic deficit, functional outcome, and dementia were quantified with the Orgogozo Scale, modified Rankin Scale, Informant Questionnaire on Cognitive Decline in the Elderly, and an extensive battery of neuropsychological tests.Results:DS were present in 43% of survivors after 6 months, 36% after 12 months, 24% after 24 months, and 18% after 36 months. The severity of the neurologic deficit at admission was the only independent predictor of DS at month 6. DS at month 6 were more frequent in patients with previous depression, dementia, and right superficial lesions. Younger age and right superficial lesions were the two variables independently associated with the presence of DS at month 36. The time course of the various DS differed, sadness remaining frequent 3 years after stroke (50%), whereas slowness, psychic slowness, lack of energy, and concentration difficulties remained frequent at month 36 in patients with dementia.Conclusion:DS are frequent after stroke. Their time course varies and depends on the cognitive status; this variation contributes to differences among previous studies on poststroke depression.

Thirty-six parkinsonian patients were selected by age of onset of over 70 and a minimum of five years duration of illness. The mean age of onset was 73.5 years and 30 patients were still alive after a mean of 7.2 years. We found that late onset Parkinson's disease has a relatively benign course with more “axial symptoms” especially dysarthria, freezing and postural instability. Dyskinesias and fluctuations are rare and dementia occurs in few patients in spite of their old age.

Importance Presymptomatic carriers of chromosome 9 open reading frame 72 (C9orf72) mutation, the most frequent genetic cause of frontotemporal lobar degeneration and amyotrophic lateral sclerosis, represent the optimal target population for the development of disease-modifying drugs. Preclinical biomarkers are needed to monitor the effect of therapeutic interventions in this population. Objectives To assess the occurrence of cognitive, structural, and microstructural changes in presymptomatic C9orf72 carriers. Design, Setting, and Participants The PREV-DEMALS study is a prospective, multicenter, observational study of first-degree relatives of individuals carrying the C9orf72 mutation. Eighty-four participants entered the study between October 2015 and April 2017; 80 (95%) were included in cross-sectional analyses of baseline data. All participants underwent neuropsychological testing and magnetic resonance imaging; 63 (79%) underwent diffusion tensor magnetic resonance imaging. Gray matter volumes and diffusion tensor imaging metrics were calculated within regions of interest. Anatomical and microstructural differences between individuals who carried the C9orf72 mutation (C9+) and those who did not carry the C9orf72 mutation (C9−) were assessed using linear mixed-effects models. Data were analyzed from October 2015 to April 2017. Main Outcomes and Measures Differences in neuropsychological scores, gray matter volume, and white matter integrity between C9+ and C9− individuals. Results Of the 80 included participants, there were 41 C9+ individuals (24 [59%] female; mean [SD] age, 39.8 [11.1] years) and 39 C9− individuals (24 [62%] female; mean [SD] age, 45.2 [13.9] years). Compared with C9− individuals, C9+ individuals had lower mean (SD) praxis scores (163.4 [6.1] vs 165.3 [5.9]; P = .01) and intransitive gesture scores (34.9 [1.6] vs 35.7 [1.5]; P = .004), atrophy in 8 cortical regions of interest and in the right thalamus, and white matter alterations in 8 tracts. When restricting the analyses to participants younger than 40 years, compared with C9− individuals, C9+ individuals had lower praxis scores and intransitive gesture scores, atrophy in 4 cortical regions of interest and in the right thalamus, and white matter alterations in 2 tracts. Conclusions and Relevance Cognitive, structural, and microstructural alterations are detectable in young C9+ individuals. Early and subtle praxis alterations, underpinned by focal atrophy of the left supramarginal gyrus, may represent an early and nonevolving phenotype related to neurodevelopmental effects of C9orf72 mutation. White matter alterations reflect the future phenotype of frontotemporal lobar degeneration/amyotrophic lateral sclerosis, while atrophy appears more diffuse. Our results contribute to a better understanding of the preclinical phase of C9orf72 disease and of the respective contribution of magnetic resonance biomarkers. Trial Registration clinicaltrials.gov Identifier: NCT02590276

The physiopathology of Alzheimer disease (AD) is complex. Associated factors, in particular at the vascular level with damaged small blood vessels, might be involved. Cerebral microbleeds(CMB) in particular, could be one of the key contributing factor in AD. The cumulative evidence suggested a sex-specific patterns of disease. Furthermore, statins might be interesting by pleitropic effects. The objectives of this study was to evaluate the interaction between vascular and neurodegenerative lesions in Alzheimer, the influence of sex, and the pharmacological modulation by atorvastatin. This experimental model is designed in a multimodal approach to ensure its scientific relevance and to fit with clinical research. The third objective is indeed to confront theresulting experimental data to the clinical data of cohorts of Alzheimer patients. With an original model of CMB in female mice, we folio wed-up them from 1.5 months to 12 months postsurgery.For the clinical part, we studied patients with AD from a database of a tertiary memory center, with standardized framework. In a translational way, we observed a cognitive and a non cognitiveimpact of CMBs, differently in wild-type mice and in diseased mice. Different outcome was noticed for young female mice. And Atorvastatine offered a mild neuroprotection particularly in presymptomatic stage. Finally, the mechanism implied will be studied, in particular the inflammatory pathway, and will help to propose targeted pharmacological modulation in order to prevent or limit the impact of CMB on AD, by offering a personalized approach.; La maladie d'Alzheimer (MA) est un processus multifactoriel. La dysfonction vasculaire pourrait être impliquée dans sa progression. Les microhémorragies cérébrales (MH) sont fréquentes chez les patients atteints de MA, et pourraient jouer un rôle clé dans le lien qui relie la dysfonction vasculaire à la MA. Le sexe pourrait également impacter sur la sévérité des lésions. Les statines ont été proposées en prévention de maladies neurodégénératives dont la MA. Leur intérêt est encore débattu mais ces molécules ont une action pléiotrope. Ce travail a pour objectif d'étudier l'impact des lésions microhémorragiques sur le déclin cognitif dans la MA, le rôle du sexe et la modulation pharmacologique par Atorvastatine, dans une perspective translationnelle,i.e. en considérant à la fois l'aspect expérimental chez l'animal et l'aspect clinique. Pour la partie expérimentale, nous avons étudié à partir d'un modèle original de MH chez les souris femelles saines et pathologiques. La MHC est créée par injection stéréotaxique de Collagénase (0,8|uUI/|iL). L'atorvastatine est administrée dans l'alimentation quotidienne des rongeurs(5mg/Kg/J). Le suivi était multimodal à trois temps différents : six semaines, six mois et douze mois après la chirurgie. Au plan clinique, nous avons étudié une base de données de patients atteints de la MA, suivis de façon standardisée. Notre travail a mis en évidence, dans une approche translationnelle, un impact cognitif et non cognitif des MHs, en présence ou non d'une maladie d'Alzheimer chez le sexe féminin. Nos résultats tendent à confirmer l'intérêt de l'atorvastatine dans la neuroprotection, grâce à ses effets pléiotropes. D'une manière générale,notre travail souligne, une fois de plus, l'intérêt d'une prise en charge personnalisée, et précoce de la MA.

Dementia is a major Public Health issue, especially due to occidental populations ageing. Nevertheless, a definite etiologic diagnosis of dementia can only be obtained by the post mortem neuropathological and/or biochemical analysis of the brain. Brain lesions leading to dementia are various in nature (neurodegenerative, vascular, metabolic...) and are often associated. We analyzed the clinical, neuropathological and biochemical data from the autopsic cohort of demented patients followed-up in Lille Memory Center (127 brains collected between 1992 and 2009). We focused on the correlation between the clinical expression of dementia and the nature of the underlying brain lesions. We show that the frequent pathological associations can modify the clinical presentation of the patients, and therefore make the etiological diagnosis of dementia more difficult. In the specific domain of frontotemporal lobar degeneration (FTLD), we investigated the clinical-pathological correlations of 18 patients who presented with progressive speech or language disorders. We established strong correlations between the various clinical syndromes and specific underlying FTLD-related proteinopathies (tau, TDP-43). We identified a new mutation in the progranuline gene in one patient. Multidisciplinary analysis of dementia helps the clinicians in improving the in vivo prediction of the nature of brain lesions. Prediction of the pathology will soon be a challenging objective for cognition and behaviour specialists when set against a context of forthcoming curative, protein-target-specific drugs., Les démences représentent un problème de santé public majeur, notamment du fait du vieillissement des populations occidentales. Pourtant, le diagnostic étiologique de certitude d'un syndrome démentiel ne peut être obtenu que par l'analyse neuropathologique et/ou biochimique du tissu cérébral obtenu en post mortem. Les lésions cérébrales aboutissant au déclin cognitif ont des origines diverses (neurodégénératives, vasculaires, métaboliques...) et sont souvent associées. En analysant les données cliniques, neuropathologiques et biochimique issues de la cohorte autopsiques de patients déments suivis au Centre Mémoire de Ressources et de recherche du CHRU de Lille (127 cerveaux prélevés entre 1992 et 2009), nous avons étudié les corrélations entre l'expression clinique du syndrome démentiel et la nature des lésions cérébrales sous jacentes. Nous montrons que les fréquentes associations lésionnelles (lésions de maladie d'Alzheimer, de maladie à corps de Lewy, lésions vasculaires) ont des conséquences sur la pertinence du diagnostic étiologique du syndrome démentiel. Dans le domaine des dégénérescences lobaires frontotemporales (DLFT), nous avons étudié les corrélations clinicopathologiques de 18 patients ayant présenté des troubles inauguraux du langage ou de la parole. Nous avons pu établir des corrélations entre les syndromes cliniques et certaines protéinopathies (tau, TDP-43) associées aux DLFT. L'enquête génétique a permis de mettre en évidence une nouvelle mutation du gène de la progranuline chez un patient. L'analyse pluridisciplinaire des démences permet au clinicien de progresser dans la prédiction des lésions cérébrales du vivant du patient. Cette démarche s'avère indispensable dans l'optique du développement de traitements curatifs des démences neurodégénératives.