1,096 research outputs found

    Progressive Apraxia of Speech: Might There Be Subtypes?

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    This study examined speech and language characteristics of three groups of individuals with neurodegenerative disease: (1) primary progressive apraxia of speech (AOS) without aphasia (N=18), (2) agrammatic primary progressive aphasia (agPPA) less severe than AOS (N=10), and (3) agPPA more severe than AOS (N=9). Findings indicate that differences in the predominant characteristics of AOS (predominance of articulatory versus prosodic abnormalities) distributed differently among the three groups, independent of AOS severity. Neuroimaging findings also differed among the groups. Results suggest that neurodegenerative AOS may include perceptually distinguishable subtypes that are related to the presence or absence of aphasia and neuroimaging findings

    Neuropathologic basis of frontotemporal dementia in progressive supranuclear palsy.

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    BackgroundProgressive supranuclear palsy (PSP) is a neurodegenerative disorder characterized by neuronal loss in the extrapyramidal system with pathologic accumulation of tau in neurons and glia. The most common clinical presentation of PSP, referred to as Richardson syndrome, is that of atypical parkinsonism with vertical gaze palsy, axial rigidity, and frequent falls. Although cognitive deficits in PSP are often ascribed to subcortical dysfunction, a subset of patients has dementia with behavioral features similar to the behavioral variant of frontotemporal dementia. In this study we aimed to identify the clinical and pathological characteristics of PSP presenting with frontotemporal dementia.MethodsIn this study, we compared clinical and pathologic characteristics of 31 patients with PSP with Richardson syndrome with 15 patients with PSP with frontotemporal dementia. For pathological analysis, we used semiquantitative methods to assess neuronal and glial lesions with tau immunohistochemistry, as well image analysis of tau burden using digital microscopic methods.ResultsWe found greater frontal and temporal neocortical neuronal tau pathology in PSP with frontotemporal dementia compared with PSP with Richardson syndrome. White matter tau pathology was also greater in PSP with frontotemporal dementia than PSP with Richardson syndrome. Genetic and demographic factors were not associated with atypical distribution of tau pathology in PSP with frontotemporal dementia.ConclusionsThe results confirm the subset of cognitive-predominant PSP mimicking frontotemporal dementia in PSP. PSP with frontotemporal dementia has distinct clinical features that differ from PSP with Richardson syndrome, as well as differences in distribution and density of tau pathology. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society

    Insects as food and feed: European perspectives on recent research and future priorities

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    This paper discusses the current state and priorities of Europe-based research on insects as food and feed, based on presentations at a workshop held in December 2015, and discussions that followed. We divide research into studies that focus on farming, health and nutrition, and those that prioritise psychological, social and political concerns. Edible insects are not necessarily universally beneficial. However, certain food insects can convert organic waste material, and provide nutrient-rich protein for humans and animals. Recent research is not concordant when trying to identify social and psychological barriers to insects as food in Europe, indicating the complexity of the issue of consumer acceptance. Innovative means of marketing insects as food include 3D printing, scientific comics, and the promotion of rural food culture in an urban setting. Edible insects are intimately connected to strong cultural and regional values, and their increasing commercialisation may empower and/or disenfranchise those who hold such values. We conclude with a discussion about the future priorities of edible insect research in Europe. We acknowledge the political nature of the ‘entomophagy’ movement. With legislative change, the insect food industry potential presents an opportunity to challenge the dynamics of current food systems. We identify the following priorities for future research: the need to better understand environmental impacts of insect procurement on both a regional and global scale, to investigate factors affecting the safety and quality of insect foods, to acknowledge the complexity of consumer acceptance, and to monitor the social and economic impacts of this growing industry.The authors would like to thank the Great British Sasakawa Foundation and BioBridge Ltd for financial support. Jonas House’s research received funding from the Economic and Social Research Council, grant number ES/J500215/1

    TEMPERATURE-DEPENDENCE OF DOMAIN-WALL COERCIVE FIELD IN MAGNETIC GARNET-FILMS

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    The coercive properties of magnetically uniaxial liquid-phase epitaxy garnet films were investigated between 10 K and the Neel temperature (T(N) less-than-or-equal-to 500 K). Two independent methods, the results of which are nearly identical (magnetical response of oscillating domain walls and the method of coercive loops measured in a vibrating sample magnetometer), were used. Besides the usual domain-wall coercive field, H(dw), the critical coercive pressure, p(dw), was also introduced as it describes in a direct way the interactions of the domain walls with the wall-pinning traps. Both H(dw) and p(dw) were found to increase exponentially with decreasing temperature. Three different types of wall-pinning traps were identified in the sample and their strength, their rate of change with temperature, and their temperature range of activity were determined

    Neuropathological background of phenotypical variability in frontotemporal dementia

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    Frontotemporal lobar degeneration (FTLD) is the umbrella term encompassing a heterogeneous group of pathological disorders. With recent discoveries, the FTLDs have been show to classify nicely into three main groups based on the major protein deposited in the brain: FTLD-tau, FTLD-TDP and FTLD-FUS. These pathological groups, and their specific pathologies, underlie a number of well-defined clinical syndromes, including three frontotemporal dementia (FTD) variants [behavioral variant frontotemporal dementia (bvFTD), progressive non-fluent aphasia, and semantic dementia (SD)], progressive supranuclear palsy syndrome (PSPS) and corticobasal syndrome (CBS). Understanding the neuropathological background of the phenotypic variability in FTD, PSPS and CBS requires large clinicopathological studies. We review current knowledge on the relationship between the FTLD pathologies and clinical syndromes, and pool data from a number of large clinicopathological studies that collectively provide data on 544 cases. Strong relationships were identified as follows: FTD with motor neuron disease and FTLD-TDP; SD and FTLD-TDP; PSPS and FTLD-tau; and CBS and FTLD-tau. However, the relationship between some of these clinical diagnoses and specific pathologies is not so clear cut. In addition, the clinical diagnosis of bvFTD does not have a strong relationship to any FTLD subtype or specific pathology and therefore remains a diagnostic challenge. Some evidence suggests improved clinicopathological association of bvFTD by further refining clinical characteristics. Unlike FTLD-tau and FTLD-TDP, FTLD-FUS has been less well characterized, with only 69 cases reported. However, there appears to be some associations between clinical phenotypes and FTLD-FUS pathologies. Clinical diagnosis is therefore promising in predicting molecular pathology

    SURVEY OF THE DEPENDENCE ON TEMPERATURE OF THE COERCIVITY OF GARNET-FILMS

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    The temperature dependence of the domain-wall coercive field of epitaxial magnetic garnets films has been investigated in the entire temperature range of the ferrimagnetic phase, and has been found to be described by a set of parametric exponents. In subsequent temperature regions different slopes were observed, with breaking points whose position was found to be sample dependent. A survey ba.ed on literature Data as well as on a large number of our own samples shows the general existence of this piecewise exponential dependence and the presence of the breaking points. This type of domain-wall coercive field temperature dependence was found in all samples in the large family of the epitaxial garnets (about 30 specimens of more than ten chemical compositionsj and also in another strongly anisotropic material (TbFeCo)

    Revisiting protein aggregation as pathogenic in sporadic Parkinson and Alzheimer diseases.

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    The gold standard for a definitive diagnosis of Parkinson disease (PD) is the pathologic finding of aggregated α-synuclein into Lewy bodies and for Alzheimer disease (AD) aggregated amyloid into plaques and hyperphosphorylated tau into tangles. Implicit in this clinicopathologic-based nosology is the assumption that pathologic protein aggregation at autopsy reflects pathogenesis at disease onset. While these aggregates may in exceptional cases be on a causal pathway in humans (e.g., aggregated α-synuclein in SNCA gene multiplication or aggregated β-amyloid in APP mutations), their near universality at postmortem in sporadic PD and AD suggests they may alternatively represent common outcomes from upstream mechanisms or compensatory responses to cellular stress in order to delay cell death. These 3 conceptual frameworks of protein aggregation (pathogenic, epiphenomenon, protective) are difficult to resolve because of the inability to probe brain tissue in real time. Whereas animal models, in which neither PD nor AD occur in natural states, consistently support a pathogenic role of protein aggregation, indirect evidence from human studies does not. We hypothesize that (1) current biomarkers of protein aggregates may be relevant to common pathology but not to subgroup pathogenesis and (2) disease-modifying treatments targeting oligomers or fibrils might be futile or deleterious because these proteins are epiphenomena or protective in the human brain under molecular stress. Future precision medicine efforts for molecular targeting of neurodegenerative diseases may require analyses not anchored on current clinicopathologic criteria but instead on biological signals generated from large deeply phenotyped aging populations or from smaller but well-defined genetic-molecular cohorts

    Logopenic and nonfluent variants of primary progressive aphasia are differentiated by acoustic measures of speech production

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    Differentiation of logopenic (lvPPA) and nonfluent/agrammatic (nfvPPA) variants of Primary Progressive Aphasia is important yet remains challenging since it hinges on expert based evaluation of speech and language production. In this study acoustic measures of speech in conjunction with voxel-based morphometry were used to determine the success of the measures as an adjunct to diagnosis and to explore the neural basis of apraxia of speech in nfvPPA. Forty-one patients (21 lvPPA, 20 nfvPPA) were recruited from a consecutive sample with suspected frontotemporal dementia. Patients were diagnosed using the current gold-standard of expert perceptual judgment, based on presence/absence of particular speech features during speaking tasks. Seventeen healthy age-matched adults served as controls. MRI scans were available for 11 control and 37 PPA cases; 23 of the PPA cases underwent amyloid ligand PET imaging. Measures, corresponding to perceptual features of apraxia of speech, were periods of silence during reading and relative vowel duration and intensity in polysyllable word repetition. Discriminant function analyses revealed that a measure of relative vowel duration differentiated nfvPPA cases from both control and lvPPA cases (r2 = 0.47) with 88% agreement with expert judgment of presence of apraxia of speech in nfvPPA cases. VBM analysis showed that relative vowel duration covaried with grey matter intensity in areas critical for speech motor planning and programming: precentral gyrus, supplementary motor area and inferior frontal gyrus bilaterally, only affected in the nfvPPA group. This bilateral involvement of frontal speech networks in nfvPPA potentially affects access to compensatory mechanisms involving right hemisphere homologues. Measures of silences during reading also discriminated the PPA and control groups, but did not increase predictive accuracy. Findings suggest that a measure of relative vowel duration from of a polysyllable word repetition task may be sufficient for detecting most cases of apraxia of speech and distinguishing between nfvPPA and lvPPA

    Developing and evaluating JIApp: Acceptability and usability of a smartphone app system to improve self-management in young people with juvenile idiopathic arthritis

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    Background: Flare-ups in juvenile idiopathic arthritis (JIA) are characterized by joint pain and swelling and often accompanied with fatigue, negative emotions, and reduced participation in activities. To minimize the impact of JIA on the physical and psychosocial development and well-being of young people (YP), it is essential to regularly monitor disease activity and side effects, as well as to support self-management such as adherence to treatment plans and engagement in general health-promoting behaviors. Smartphone technology has the potential to engage YP with their health care through convenient self-monitoring and easy access to information. In addition, having a more accurate summary of self-reported fluctuations in symptoms, behaviors, and psychosocial problems can help both YP and health care professionals (HCPs) better understand the patient’s condition, identify barriers to self-management, and assess treatment effectiveness and additional health care needs. No comprehensive smartphone app has yet been developed in collaboration with YP with JIA, their parents, and HCPs involved in their care. Objectives: The objective of this study was to design, develop, and evaluate the acceptability and usability of JIApp, a self-management smartphone app system for YP with JIA and HCPs. Methods: We used a qualitative, user-centered design approach involving YP, parents, and HCPs from the rheumatology team. The study was conducted in three phases: (1) phase I focused on developing consensus on the features, content, and design of the app; (2) phase II was used for further refining and evaluating the app prototype; and (3) phase III focused on usability testing of the app. The interview transcripts were analyzed using qualitative content analysis. Results: A total of 29 YP (aged 10-23, median age 17) with JIA, 7 parents, and 21 HCPs were interviewed. Major themes identified as the ones that helped inform app development in phase I were: (1) remote monitoring of symptoms, well-being, and activities; (2) treatment adherence; and (3) education and support. During phase II, three more themes emerged that informed further refinement of the app prototype. These included (4) adapting a reward system to motivate end users for using the app; (5) design of the app interface; and (6) clinical practice integration. The usability testing during phase III demonstrated high rates of overall satisfaction and further affirmed the content validity of the app. Conclusions: We present the development and evaluation of a smartphone app to encourage self-management and engagement with health care for YP with JIA. The app was found to have high levels of acceptability and usability among YP and HCPs and has the potential to improve health care and outcomes for this age group. Future feasibility testing in a prospective study will firmly establish the reliability, efficacy, and cost-effectiveness of such an app intervention for patients with arthritis
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