Effectiveness of a rehabilitation dog in fostering gait retraining for adults with a recent stroke: A multiple single-case study

Introduction: Gait retraining approaches and walking aids currently used for patients with recent stoke present limitations regarding their utilization in clinical and real life settings. A rehabilitation facility implemented an innovative approach using a rehabilitation dog for gait retraining and as a walking aid. Objective: To explore the effectiveness of rehabilitation dog, both as a gait retraining approach and as a walking aid, to improve walking speed and gait pattern. Methods: Four participants, post recent stroke with hemiparesis, were recruited in a rehabilitation unit. A multiple singlecase ABA design was used. The threeweek training period focused on gait retraining using a rehabilitation dog. For each session, walking speed with the rehabilitation dog and the cane was documented. In each phase (ABA), the gait pattern was analyzed. Results: Mean (SD) age of the participants was 58 (3.2) years old; time since stroke was 88 (61.41) days. For three participants, walking speed was significantly increased after retraining with the dog. The four participants showed improvement of their gait pattern across phases and walked significantly faster with the dog than with the cane. Conclusion: This pilot study suggests that a rehabilitation dog is an interesting gait retraining approach for a clinical setting and an effective walking aid following stroke

A Drosophila Model for Clostridium difficile Toxin CDT Reveals Interactions with Multiple Effector Pathways.

Clostridium difficile infections (CDIs) cause severe and occasionally life-threatening diarrhea. Hyper-virulent strains produce CDT, a toxin that ADP-ribosylates actin monomers and inhibits actin polymerization. We created transgenic Drosophila lines expressing the catalytic subunit CDTa to investigate its interaction with host signaling pathways in vivo. When expressed in the midgut, CDTa reduces body weight and fecal output and compromises survival, suggesting severe impairment of digestive functions. At the cellular level, CDTa induces F-actin network collapse, elimination of the intestinal brush border, and disruption of intercellular junctions. We confirm toxin-dependent re-distribution of Rab11 to enterocytes' apical surface and observe suppression of CDTa phenotypes by a Dominant-Negative form of Rab11 or RNAi of the dedicated Rab11GEF Crag (DENND4). We also report that Calmodulin (Cam) is required to mediate CDTa activity. In parallel, chemical inhibition of the Cam/Calcineurin pathway by Cyclosporin A or FK506 also reduces CDTa phenotypes, potentially opening new avenues for treating CDIs

Performance-based Tools for Assessing Functional Performance in Individuals with Mild Cognitive Impairment

Background: It is now recognized that individuals with mild cognitive impairment (MCI) face subtle functional declines that can compromise performance in everyday tasks. However, it is still not clear how to capture these declines in the clinical setting. Thus, the goal of this study was to conduct a scoping review to identify performance-based tools for which the psychometric properties have been evaluated with the MCI population. Methods: A scoping review of the scientific literature was performed with the guidance of a health science librarian in searching the MEDLINE, PsychINFO, CINAHL, and EMBASE databases from their inception until May 2014. Results: Nine performance-based tools assessing functional performance in individuals with MCI have been identified in the literature. While construct and content validity have been extensively reported, only two tools provided data on reliability. Conclusion: Considering that functional decline is part of the normal aging process, it might be challenging to differentiate normal from pathological functional decline in this population. Functional measurement tools might be very sensitive to capture these subtle changes. Although no recommendations can be proposed at this point on a specific tool to assess functional performance in MCI, research in this area is beginning to identify the elements that should be taken into consideration when choosing a tool

A MEG study of the neural substrates of semantic processing in semantic variant primary progressive aphasia

Despite a well-documented pattern of semantic memory (SM) impairment, the patterns of brain activation during semantic processing in svPPA still remain poorly understood. The current study aimed to investigate the neural substrates of residual semantic processing in the context of this significant but selective SM impairment, through the case study of one svPPA patient. One svPPA patient (EC) and six elderly controls carried out a general-level semantic categorization task (biological and manufactured objects) while their brain activity was recorded using magnetoencephalography (MEG). Despite similar behavioral performance, EC showed hyperactivation of the left inferior temporal gyrus (ITG) and right anterior temporal lobe (ATL) relative to controls. This suggests that periatrophic regions within the ATL region may support preserved semantic abilities in svPPA. These results thus contribute to our understanding of the brain regions which are recruited to compensate for bilateral atrophy of the ATL and ensure residual semantic processing in svPPA

Leisure practice and its relations to cognitive vitality for seniors attending community organizations

The purpose of this study was to explore the relations between certain dimensions of leisure practice and cognitive vitality in seniors and identify which of their sociodemographic and health characteristics (SHC) are related to leisure practice. A cross-sectional analysis of leisure practice, cognitive performance, self-perceived memory and SHC was performed among 294 French-speaking Canadian seniors attending community centres (255 women, average age: 71), by multiple linear regressions and partial correlations controlled for SHC. Outcomes from the project show that the diversity of leisure was related to the Montreal Cognitive Assessment and the California Verbal Learning Test, the frequency of cognitive leisure was associated to the Stroop Test, and the frequency of social leisure showed no significant association. “Paper and pencil games”, “computer use” and “helping a sibling” were related to various cognitive tests. Frequency of leisure (total) was related to gender and education, and diversity of leisure was related to education, age and depression. Study outcomes indicate that diversity of leisure was more related to cognitive vitality than frequency. Future studies should address leisure diversity as a way to promote cognitive vitality among seniors. Moreover, seniors’ characteristics should be considered when seeking to facilitate their participation in leisure activities.Le but de cette étude était d’explorer les relations entre certaines dimensions de la pratique de loisirs et la vitalité cognitive chez des aînés et d’identifier leurs caractéristiques sociodémographiques et de santé (CSS) qui étaient liées à leur pratique de loisirs. Une analyse transversale de la pratique de loisirs, de la performance cognitive, du niveau perçu de la mémoire et des CSS a été réalisée auprès de 294 aînés canadiens parlant français et qui participaient aux activités d’un centre communautaire (255 femmes, âge moyen : 71 ans), par des régressions linéaires multiples et des corrélations partielles contrôlées pour les CSS. Les résultats montrent que la variété des loisirs était liée au Montreal Cognitive Assessment et au California Verbal Learning Test, que la fréquence des loisirs cognitifs était associée au test de Stroop et que la fréquence des loisirs sociaux ne montrait aucune association. Les « jeux papier-crayon », « l’utilisation de l’ordinateur » et « prendre soin d’un proche » étaient reliés à plusieurs tests cognitifs. La fréquence totale des loisirs était liée au sexe et à l’éducation et la variété des loisirs était liée à l’éducation, à l’âge et à la dépression. Les résultats de cette étude montrent que la variété des loisirs était davantage liée à la vitalité comparée à la fréquence des loisirs. De futures études devraient aborder la variété des loisirs comme une manière de promouvoir la vitalité cognitive chez les aînées. De plus, les caractéristiques des aînés devraient être considérées afin de favoriser leur participation aux activités de loisirs dans les centres communautaires

Posterior cortical atrophy : impact on daily living activities and exploration of a cognitive rehabilitation approach

Posterior cortical atrophy (PCA) is a neurodegenerative disease affecting the posterior region of the brain. Little is known about both the impact of PCA on functioning and how to support patients on a daily basis. The purpose of this study was to describe the functional profile of DD, a woman diagnosed with PCA, as well as to explore a pilot cognitive rehabilitation program designed to optimize functioning in daily living. The ADL Profile was used to assess the daily tasks that DD chose to undertake. Four operations, i.e. formulate a goal, plan, carry out and verify goal attainment, were scored for each task. Difficulties were observed during the execution of all tasks, as she struggled to find items or showed unsafe behaviors. Impairments were also seen in formulating a goal and planning, especially for less routine tasks. DD identified two tasks to be addressed in rehabilitation: setting the table and dealing cards. Learning was optimized using errorless learning and compensatory aids when setting the table, while dealing cards received no intervention. Only setting the table improved significantly with time. Further studies should be conducted to portray a wider functional profile of people living with PCA and develop effective rehabilitation programs