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BackgroundPause duration analysis is a common feature in the study of discourse in Alzheimer’s disease (AD) and may also be helpful for its early detection. However, studies involving patients with amnestic mild cognitive impairment (aMCI) have yielded varying results.ObjectivesTo characterize the probability density distribution of speech pause durations in AD, two multi-domain amnestic MCI patients (with memory encoding deficits, a-mdMCI-E, and with retrieval impairment only, a-mdMCI-R) and healthy controls (HC) in order check whether there are significant differences between them.Method112 picture-based oral narratives were manually transcribed and annotated for the automatic extraction and analysis of pause durations. Different probability distributions were tested for the fitting of pause durations while truncating shorter ranges. Recent findings in the field of Statistics were considered in order to avoid the inherent methodological uncertainty that this type of analysis entails.ResultsA lognormal distribution (LND) explained the distribution of pause duration for all groups. Its fitted parameters (µ,σ) followed a gradation from the group with shorter durations and a higher tendency to produce short pauses (HC) to the group with longer pause durations and a considerably higher tendency to produce long pauses with greater variance (AD). Importantly, a-mdMCI-E produced significantly longer pauses and with greater variability than their a-mdMCI-R counterparts (α= 0.05).ConclusionWe report significant differences at the group level in pause distribution across all groups of study that could be used in future diagnostic tools and discuss the clinical implications of these findings, particularly regarding the characterization of aMCI.

Lifelong bilingualism may contribute to cognitive reserve (CR) in neurodegenerative diseases as shown by a delay of the age at symptom onset in bilinguals with Alzheimer’s disease (AD) and Mild Cognitive Impairment (MCI). However, some studies have failed to show this bilingual advantage, suggesting that it might depend on the type and degree of bilingualism. In the present study, we tested the hypothesis that active bilingualism, defined as the continuous use of the two languages as opposed to second language exposition only, may protect against cognitive decline. Moreover, we investigated whether bilingualism as a CR factor may be explained by an advantage within the executive control (EC) system. To do so, we collected clinical measures (age at onset of cognitive symptoms, age at the first medical visit for cognitive impairments, and age at diagnosis) in patients with MCI and patients with AD with different degrees of language experience and usage of Catalan and Spanish. Additionally, all participants were tested on four EC tasks and one long-term memory recognition task. First, results from multiple regression analyses showed that active bilingualism was a significant predictor of delay in the age at onset for all the clinical measures in MCI, but not AD patients. Second, the effect of active bilingualism was independent of occupation, educational level and job attainment across the individuals’ lifespan. Finally, although we did not find an effect of active bilingualism across all EC tasks, we did find an effect for conflict resolution. These results are discussed in the context of CR hypotheses, suggesting that compensatory mechanisms may play a role in protecting against cognitive decline. This work was supported by the Fundació La Marató de TV3 (373/C/2014), the European Union’s Seventh Framework Program for Research (No. 613465), the Agencia Estatal de Investigación (AEI, National Research Agency) and Fondo Europeo de Desarrollo Regional (FEDER, European Regional Development Fund) under the projects PSI2017-87784-R and RED2018-102615-T. The Ramón y Cajal research program of the Spanish Ministry of Science, Innovation, and Universities supported MC (RYC-2013-14013) and MH (RYC-2016-19477).

Introduction: Neuroinflammation is a potential player in neurodegenerative conditions, particularly the aggressive ones, such as multiple system atrophy (MSA). Previous reports on cytokine levels in MSA using serum or cerebrospinal fluid (CSF) have been inconsistent, including small samples and a limited number of cytokines, often without comparison to Parkinson's disease (PD), a main MSA differential diagnosis. Methods: Cross-sectional study of CSF levels of 38 cytokines using a multiplex assay in 73 participants: 39 MSA patients (19 with parkinsonian type [MSAp], 20 with cerebellar type [MSAc]; 31 probable, 8 possible), 19 PD patients and 15 neurologically unimpaired controls. None of the participants was under non-steroidal anti-inflammatory drugs at the time of the lumbar puncture. Results: There were not significant differences in sex and age among participants. In global non-parametric comparisons FDR-corrected for multiple comparisons, CSF levels of 5 cytokines (FGF-2, IL-10, MCP-3, IL-12p40, MDC) differed among the three groups. In pair-wise FDR-corrected non-parametric comparisons 12 cytokines (FGF-2, eotaxin, fractalkine, IFN-α2, IL-10, MCP-3, IL-12p40, MDC, IL-17, IL-7, MIP-1β, TNF-α) were significantly higher in MSA vs. non-MSA cases (PD + controls pooled together). Of these, MCP-3 and MDC were the most significant ones, also differed in MSA vs. PD, and were significant MSA-predictors in binary logistic regression models and ROC curves adjusted for age. CSF levels of fractalkine and MIP-1α showed a strong and significant positive correlation with UMSARS-2 scores. Conclusion: Increased CSF levels of cytokines such as MCP-3, MDC, fractalkine and MIP-1α deserve consideration as potential diagnostic or severity biomarkers of MSA. info:eu-repo/semantics/publishedVersion

Introduction The finding of mutations of the COQ2 gene and reduced coenzyme Q10 levels in the cerebellum in multiple system atrophy (MSA) suggest that coenzyme Q10 is relevant to MSA pathophysiology. Two recent studies have reported reduced coenzyme Q10 levels in plasma and serum (respectively) of MSA patients compared to Parkinson's disease and/or control subjects, but with largely overlapping values, limited comparison with other parkinsonisms, or dependence on cholesterol levels. We hypothesized that cerebrospinal fluid (CSF) is reliable to assess reductions in coenzyme Q10 as a candidate biomarker of MSA. Methods In this preliminary cross-sectional study we assessed CSF coenzyme Q10 levels in 20 patients with MSA from the multicenter Catalan MSA Registry and of 15 PD patients, 10 patients with progressive supranuclear palsy (PSP), and 15 control subjects from the Movement Disorders Unit Biosample Collection of Hospital Clinic de Barcelona. A specific ELISA kit was used to determine CSF coenzyme Q10 levels. CSF coenzyme Q10 levels were compared in MSA vs. the other groups globally, pair-wise, and by binary logistic regression models adjusted for age, sex, disease severity, disease duration, and dopaminergic treatment. Results CSF coenzyme Q10 levels were significantly lower in MSA than in other groups in global and pair-wise comparisons, as well as in multivariate regression models. Receiver operating characteristic curve analyses yielded significant areas under the curve for MSA vs. PD, PSP and controls. Conclusions These findings support coenzyme Q10 relevance in MSA. Low CSF coenzyme Q10 levels deserve further consideration as a biomarker of MSA.