Search results for "Movement"
showing 10 items of 2021 documents
Connexin-30 mRNA Is Up-Regulated in Astrocytes and Expressed in Apoptotic Neuronal Cells of Rat Brain Following Kainate-Induced Seizures
2002
Glial connexins (Cxs) make an extensively interconnected functional syncytium created by a network of gap junctions between astrocytes and oligodendrocytes. Among Cxs expressed in the brain, Cx30 is expressed in grey matter astrocytes, as shown at the protein level by immunoistochemistry. In the present study we aimed to perform a detailed study of the regional distribution of Cx30 mRNA in the adult and postnatal developing rat brain, analyzing its expression by in situ hybridization, and determining its cell type localization by double labeling. Recently, it has been suggested that neuronal activity may control the level of intercellular communication between astrocytes through gap junctio…
Aging affects the mental simulation/planning of the "rising from the floor" sequence.
2010
We investigated the effect of aging on the ability to mentally simulate/plan a complex sequential action of the whole body, namely "rising from the floor". Forty-four non-demented elderly people (mean age: 85.2±5.5 years) and 20 young people (mean age: 26.6±4.9 years) were included in the study. They were required to put in order six images representing the main movements necessary to get up from a sitting position on the floor. We showed that older subjects had poorer performance-both in terms of proportion of success and response time-than their younger counterparts. These results are in line with previous findings showing age-related alterations in action simulation/action planning proce…
Age-related differences in a delayed pointing of a M�ller-Lyer illusion
2003
It has been suggested that movements to visible or remembered targets are differently sensitive to the Müller-Lyer (ML) illusion. Indeed, when the target is continuously visible, movements rely on the veridical object characteristics, whereas remembered movements are thought to reflect the perceived characteristics of the object. The aim of the present study was to determine how movements to visible or remembered targets are influenced by the ML illusion in children aged 7 to 11 years old. Participants were asked to make a perceptual judgment or to point a shaft extremity of the ML configurations (Closed, Control, and Open) in three visual conditions (Closed Loop, Open Loop-0-s delay, and 5…
Differential expression of PGC-1α and metabolic sensors suggest age-dependent induction of mitochondrial biogenesis in Friedreich ataxia fibroblasts.
2011
11 pages, 6 figures. PMID:21687738[PubMed] PMCID: PMC3110204
Cellular expression of connexins in the rat brain: neuronal localization, effects of kainate-induced seizures and expression in apoptotic neuronal ce…
2003
The identification of connexins (Cxs) expressed in neuronal cells represents a crucial step for understanding the direct communication between neurons and between neuron and glia. In the present work, using a double-labelling method combining in situ hybridization for Cx mRNAs with immunohistochemical detection for neuronal markers, we provide evidence that, among cerebral connexins (Cx26, Cx32, Cx36, Cx37, Cx40, Cx43, Cx45 and Cx47), only Cx45 and Cx36 mRNAs are localized in neuronal cells in both developing and adult rat brain. In order to establish whether connexin expression is influenced in vivo by abnormal neuronal activity, we examined the short-term effects of kainate-induced seizur…
Saccadic eye movements: what do they tell us about aging cognition?
2016
ABSTRACTAlthough the relationship between age-related cognitive decline and saccadic eye movement (SEM) deficits has been outlined, specific cognitive alterations underlying age-related changes in saccadic performance remain unclear. This study attempted to better understand the nature of aging effects on SEMs. We compared SEMs in younger and older adults in prosaccade (PS) and antisaccade (AS) tasks under gap, step, and overlap conditions. We also examined relationships between these performances and several neuropsychological scores. Twenty-eight younger adults (YA), 24 older adults under 65 years (OA 65) of age completed a neuropsychological evaluation, PS and AS tasks. Our results showe…
Shifts in Key Time Points and Strategies for a Multisegment Motor Task in Healthy Aging Subjects
2018
International audience; In this study, we compared key temporal points in the whole body pointing movement of healthy aging and young subjects. During this movement, subject leans forward from a standing position to reach a target. As it involves forward inclination of the trunk, the movement creates a risk for falling. We examined two strategic time points during the task-first, the crossover point where the velocity of the center of mass (CoM) in the vertical dimension outstripped the velocity in the anteroposterior dimension and secondly, the time to peak of the CoM velocity profile. Transitions to stabilizing postures occur at these time points. They both occurred earlier in aging subje…
Practice-Related Improvements in Postural Control During Rapid Arm Movement in Older Adults: A Preliminary Study
2012
International audience; Background. Postural control associated with self-paced movement is critical for balance in older adults. The present study aimed to investigate the effects of a virtual reality based program on the postural control associated with rapid arm movement in this population. Methods. From an upright standing position, participants performed rapid arm raising movements toward a target. Practice-related changes were assessed by pre- and posttest comparisons of hand kinematics and center of pressure displacement parameters measured in a training group (mean age: 71.50 +/- 2.67 years, n = 8) and a control group (mean age: 72.87 +/- 3.09 years, n = 8). Training group participa…
Comparison of motor strategies in sit-to-stand and back-to-sit motions between healthy and Alzheimer’s disease elderly subjects
2005
We studied the kinematics of shoulder displacement during sit-to-stand and back-to-sit in 6 healthy elderly subjects and six elderly subjects with mild to moderate Alzheimer's disease in order to elucidate the impact of Alzheimer's disease on motor planning and control processes. During sit-to-stand, Alzheimer's disease subjects reduced their forward displacement and started their upward displacement earlier than healthy elderly subjects. Furthermore, shoulder path curvatures were more pronounced for upward compared with downward displacement in healthy elderly group, in contrast with Alzheimer's disease group. Temporal analysis found that: 1) for both groups, profiles of velocity of sit-to…
Therapeutic effects of hMAPC and hMSC transplantation after stroke in mice.
2012
Stroke represents an attractive target for stem cell therapy. Although different types of cells have been employed in animal models, a direct comparison between cell sources has not been performed. The aim of our study was to assess the effect of human multipotent adult progenitor cells (hMAPCs) and human mesenchymal stem cells (hMSCs) on endogenous neurogenesis, angiogenesis and inflammation following stroke. BALB/Ca-RAG 2(-/-) γC(-/-) mice subjected to FeCl(3) thrombosis mediated stroke were intracranially injected with 2 × 10(5) hMAPCs or hMSCs 2 days after stroke and followed for up to 28 days. We could not detect long-term engraftment of either cell population. However, in comparison w…