A sociodemographic and neuropsychological characterization of an illiterate population

The objectives of this article are to characterize the performance and to discuss the performance differences between literate and illiterate participants in a well-defined study population. We describe the participant-selection procedure used to investigate this population. Three groups with similar sociocultural backgrounds living in a relatively homogeneous fishing community in southern Portugal were characterized in terms of socioeconomic and sociocultural background variables and compared on a simple neuropsychological test battery; specifically, a literate group with more than 4 years of education (n = 9), a literate group with 4 years of education (n = 26), and an illiterate group (n = 31) were included in this study. We compare and discuss our results with other similar studies on the effects of literacy and illiteracy. The results indicate that naming and identification of real objects, verbal fluency using ecologically relevant semantic criteria, verbal memory, and orientation are not affected by literacy or level of formal education. In contrast, verbal working memory assessed with digit span, verbal abstraction, long-term semantic memory, and calculation (i.e., multiplication) are significantly affected by the level of literacy. We indicate that it is possible, with proper participant-selection procedures, to exclude general cognitive impairment and to control important sociocultural factors that potentially could introduce bias when studying the specific effects of literacy and level of formal education on cognitive brain function

The application of rules in morphology, syntax and number processing: a case of selective deficit of procedural or executive mechanisms?: Deficit of procedural or executive mechanisms

International audienceDeclarative memory is a long-term store for facts, concepts and words. Procedural memory subserves the learning and control of sensorimotor and cognitive skills, including the mental grammar. In this study, we report a single-case study of a mild aphasic patient who showed procedural deficits in the presence of preserved declarative memory abilities. We administered several experiments to explore rule application in morphology, syntax and number processing. Results partly support the differentiation between declarative and procedural memory. Moreover, the patient's performance varied according to the domain in which rules were to be applied, which underlines the need for more fine-grained distinctions in cognition between procedural rules

The ataxia protein sacsin is a functional co-chaperone that protects against polyglutamine-expanded ataxin-1

An extensive protein–protein interaction network has been identified between proteins implicated in inherited ataxias. The protein sacsin, which is mutated in the early-onset neurodegenerative disease autosomal recessive spastic ataxia of Charlevoix-Saguenay, is a node in this interactome. Here, we have established the neuronal expression of sacsin and functionally characterized domains of the 4579 amino acid protein. Sacsin is most highly expressed in large neurons, particularly within brain motor systems, including cerebellar Purkinje cells. Its subcellular localization in SH-SY5Y neuroblastoma cells was predominantly cytoplasmic with a mitochondrial component. We identified a putative ubiquitin-like (UbL) domain at the N-terminus of sacsin and demonstrated an interaction with the proteasome. Furthermore, sacsin contains a predicted J-domain, the defining feature of DnaJ/Hsp40 proteins. Using a bacterial complementation assay, the sacsin J-domain was demonstrated to be functional. The presence of both UbL and J-domains in sacsin suggests that it may integrate the ubiquitin–proteasome system and Hsp70 function to a specific cellular role. The Hsp70 chaperone machinery is an important component of the cellular response towards aggregation prone mutant proteins that are associated with neurodegenerative diseases. We therefore investigated the effects of siRNA-mediated sacsin knockdown on polyglutamine-expanded ataxin-1. Importantly, SACS siRNA did not affect cell viability with GFP-ataxin-1[30Q], but enhanced the toxicity of GFP-ataxin-1[82Q], suggesting that sacsin is protective against mutant ataxin-1. Thus, sacsin is an ataxia protein and a regulator of the Hsp70 chaperone machinery that is implicated in the processing of other ataxia-linked proteins

Rest and Dobutamine stress echocardiography in the evaluation of mid-term results of mitral valve repair in Barlow's disease

BACKGROUND: Surgical "anatomical" repair is the most frequent technique used to correct mitral regurgitation due to severe myxomatous valve disease. Debate, however, persists on the efficacy of this technique, as well as on the durability of the repaired valve, and on its functioning and hemodynamics under stress conditions. Thus, a basal and Dobutamine echocardiographic (DSE) study was carried out to evaluate these parameters at mid-term follow-up. METHODS AND RESULTS: Twenty patients selected for the study (12 men and 8 women, mean age 60 ± 9 years) underwent pre- and post-operative transthoracic echocardiography (TTE) and intra-operative transesophageal echocardiography (TEE). At mid-term follow-up (20 ± 5 months) all patients underwent rest TTE and DSE (3 min. dose increments up to 40 microg/Kg/min protocol). Pre-discharge and one-month TTE showed absence of MR in 11 pts., trivial or mild MR in 9 pts. and normal mitral valve area and gradients. Mid-term TTE showed decrease in left atrial and ventricular dimension, in pulmonary artery pressure (sPAP) and grade of MR. During DSE a significant increase in mitral valve area, maximum and mean gradients, sPAP, heart rate and cardiac output and a decrease in systolic annular diameter and left ventricular volume were found; in 6 pts. a transient left ventricular outflow tract obstruction was observed. CONCLUSION: Basal and Dobutamine stress echocardiography proved to be valuable tools for evaluation of mid-term results of mitral valve repair. In our study population, the surgical technique employed had a favourable impact on several cardiac parameters, evaluated by these methods

Using PET with 18F-AV-45 (florbetapir) to quantify brain amyloid load in a clinical environment

International audiencePURPOSE: Positron emission tomography (PET) imaging of brain amyloid load has been suggested as a core biomarker for Alzheimer's disease (AD). The aim of this study was to test the feasibility of using PET imaging with (18)F-AV-45 (florbetapir) in a routine clinical environment to differentiate between patients with mild to moderate AD and mild cognitive impairment (MCI) from normal healthy controls (HC). METHODS: In this study, 46 subjects (20 men and 26 women, mean age of 69.0 ± 7.6 years), including 13 with AD, 12 with MCI and 21 HC subjects, were enrolled from three academic memory clinics. PET images were acquired over a 10-min period 50 min after injection of florbetapir (mean ± SD of radioactivity injected, 259 ± 57 MBq). PET images were assessed visually by two individuals blinded to any clinical information and quantitatively via the standard uptake value ratio (SUVr) in the specific regions of interest, which were defined in relation to the cerebellum as the reference region. RESULTS: The mean values of SUVr were higher in AD patients (median 1.20, Q1-Q3 1.16-1.30) than in HC subjects (median 1.05, Q1-Q3 1.04-1.08; p = 0.0001) in the overall cortex and all cortical regions (precuneus, anterior and posterior cingulate, and frontal median, temporal, parietal and occipital cortex). The MCI subjects also showed a higher uptake of florbetapir in the posterior cingulate cortex (median 1.06, Q1-Q3 0.97-1.28) compared with HC subjects (median 0.95, Q1-Q3 0.82-1.02; p = 0.03). Qualitative visual assessment of the PET scans showed a sensitivity of 84.6% (95% CI 0.55-0.98) and a specificity of 38.1% (95% CI 0.18-0.62) for discriminating AD patients from HC subjects; however, the quantitative assessment of the global cortex SUVr showed a sensitivity of 92.3% and specificity of 90.5% with a cut-off value of 1.122 (area under the curve 0.894). CONCLUSION: These preliminary results suggest that PET with florbetapir is a safe and suitable biomarker for AD that can be used routinely in a clinical environment. However, the low specificity of the visual PET scan assessment could be improved by the use of specific training and automatic or semiautomatic quantification tools