Long-term voluntary running modifies the levels of proteins of the excitatory/inhibitory system and reduces reactive astrogliosis in the brain of Ts65Dn mouse model for Down syndrome.

We showed previously that voluntary long-term running improved cognition and motor skills, but in an age-dependent manner, in the Ts65Dn mouse model for Down syndrome (DS). Presently, we investigated the effect of running on the levels of some key proteins of the excitatory/inhibitory system, which is impaired in the trisomic brain, and on astroglia, a vital component of this system. Ts65Dn mice had free access to a running wheel for 9-13 months either from weaning or from the age of 7 months. Sedentary Ts65Dn mice served as controls. We found that running modified the levels of four of the seven proteins we tested that are associated with the glutamatergic/GABA-ergic system. Thus, Ts65Dn runners demonstrated increased levels of glutamine synthetase and metabotropic glutamate receptor 1 and decreased levels of glutamate transporter 1 and glutamic acid decarboxylase 65 (GAD65) versus sedentary mice, but of metabotropic glutamate receptor 1 and GAD65 only in the post-weaning cohort. GAD67, ionotropic N-methyl-D-aspartate type receptor subunit 1, and GABAAα5 receptors' levels were similar in runners and sedentary animals. The number of glial fibrillary acidic protein (GFAP)-positive astrocytes and the levels of GFAP were significantly reduced in runners relative to sedentary mice. Our study provides new insight into the mechanisms underlying the beneficial effect of voluntary, sustained running on function of the trisomic brain by identifying the involvement of proteins associated with glutamatergic and GABAergic systems and reduction in reactive astrogliosis.

White matter involvement in young non-demented Down's syndrome subjects: a tract-based spatial statistic analysis.

PURPOSE: Cognitive decline in Down syndrome generally shows neurodegenerative aspects similar to what is observed in Alzheimer's disease. Few studies reported information on white matter integrity. The aim of this study was to evaluate white matter alterations in a cohort of young Down subjects, without dementia, by means of DTI technique, compared to a normal control group. METHODS: The study group consisted of 17 right-handed subjects with DS and many control subjects. All individuals participating in this study were examined by MR exam including DTI acquisition (32 non-coplanar directions); image processing and analysis were performed using FMRIB Software Library (FSL version 4.1.9, http://www.fmrib.ox.ac.uk/fsl )) software package. Finally, the diffusion tensor was estimated voxel by voxel and the FA map derived from the tensor. A two-sample t test was performed to assess differences between DS and control subjects. RESULTS: The FA is decreased in DS subjects, compared to control subjects, in the region of the anterior thalamic radiation, the inferior fronto-occipital fasciculum, the inferior longitudinal fasciculum, and the cortico-spinal tract, bilaterally. CONCLUSIONS: The early white matter damage visible in our DS subjects could have great impact in the therapeutic management, in particular in better adapting the timing of therapies to counteract the toxic effect of the deposition of amyloid that leads to oxidative stress.

Three dimensional motion capture applied to violin playing: A study on feasibility and characterization of the motor strategy.

BACKGROUND AND OBJECTIVE: Playing string instruments requires advanced motor skills and a long training that is often spent in uncomfortable postures that may lead to injuries or musculoskeletal disorders. Thus, it is interesting to objectively characterize the motor strategy adopted by the players. In this work, we implemented a method for the quantitative analysis of the motor performance of a violin player. METHODS: The proposed protocol takes advantage of an optoelectronic system and some infra-red reflecting markers in order to track player's motion. The method was tested on a professional violin player performing a legato bowing task. The biomechanical strategy of the upper limb and bow positioning were described by means of quantitative parameters and motion profiles. Measured quantities were: bow trajectory, angles, tracks, velocity, acceleration and jerk. RESULTS: A good repeatability of the bowing motion (CV < 2%) and high smoothness (jerk < 5 m/s3) were observed. Motion profiles of shoulder, elbow and wrist were repeatable (CV < 7%) and comparable to the curves observed in other studies. Jerk and acceleration profiles demonstrated high smoothness in the ascending and descending phases of bowing. High variability was instead observed for the neck angle (CV ∼56%). CONCLUSIONS: "Quantitative" measurements, instead of "qualitative" observation, can support the diagnosis of motor disorders and the accurate evaluation of musicians' skills. The proposed protocol is a powerful tool for the description of musician's performance, that may be useful to document improvements in playing abilities and to adjust training strategies.

Effects of a single session of transcranial direct current stimulation on upper limb movements in children with cerebral palsy: A randomized, sham-controlled study.

INTRODUCTION: Motor impairment in children with spastic hemiparetic cerebral palsy (CP) is generally more prominent in the affected upper limb, leading to limitations in hand function stemming from deficiencies in motor coordination and selective motor control as well as muscle weakness, slower execution of movements and deficient integration of sensory-motor information. OBJECTIVE: Determine the effect of a single session of anodal transcranial direct current stimulation (tDCS) combined with functional training on the spatiotemporal variables of upper arm movements in children with spastic hemiparesis. METHOD: A randomized, sham-controlled trial with a blinded evaluator was conducted involving 20 children with CP between 6 and 12 years of age. The spatiotemporal variables of the upper limbs were analyzed by comparing the results of Evaluation 1 (before stimulation) and Evaluation 2 (immediately after stimulation). The protocol consisted of a 20-minute session of functional training of the paretic upper limb combined with tDCS administered over the primary motor cortex of the hemisphere contralateral to the motor impairment at an intensity of 1 mA. The participants were randomly allocated to two groups: experimental group (anodal tDCS) and control group (sham tDCS). RESULTS: Statistically significant (p < 0.05) reductions in total movement duration and returning movement duration were found in both the paretic and non-paretic limbs in the group submitted to active tDCS. No significant differences were found in the control group for any of the variables analyzed. CONCLUSION: A single session of anodal tDCS over the primary motor cortex of the hemisphere ipsilateral to the brain lesion led to momentary motor improvements in both upper limbs of the children with spastic hemiparetic CP analyzed in the present study.

Transcranial direct current stimulation combined with upper limb functional training in children with spastic, hemiparetic cerebral palsy: study protocol for a randomized controlled trial.

BACKGROUND: The aim of the proposed study is to perform a comparative analysis of functional training effects for the paretic upper limb with and without transcranial direct current stimulation over the primary motor cortex in children with spastic hemiparetic cerebral palsy. METHODS: The sample will comprise 34 individuals with spastic hemiparetic cerebral palsy, 6 to 16 years old, classified at level I, II, or III of the Manual Ability Classification System. Participants will be randomly allocated to two groups: (1) functional training of the paretic upper limb combined with anodic transcranial stimulation; (2) functional training of the paretic upper limb combined with sham transcranial stimulation. Evaluation will involve three-dimensional movement analysis and electromyography using the SMART-D 140® system (BTS Engineering) and the FREEEMG® system (BTS Engineering), the Quality of Upper Extremity Skills Test, to assess functional mobility, the Portable Device and Ashworth Scale, to measure movement resistance and spasticity, and the Pediatric Evaluation of Disability Inventory, to evaluate performance. Functional reach training of the paretic upper limb will include a range of manual activities using educational toys associated with an induced constraint of the non-paretic limb during the training. Training will be performed in five weekly 20-minute sessions for two weeks. Transcranial stimulation over the primary motor cortex will be performed during the training sessions at an intensity of 1 mA. Findings will be analyzed statistically considering a 5 % significance level (P ≤ 0.05). DISCUSSION: This paper presents a detailed description of a prospective, randomized, controlled, double-blind, clinical trial designed to demonstrate the effects of combining transcranial direct current stimulation over the primary motor cortex and functional training of the paretic limb in children with cerebral palsy classified at level I, II, or III of the Manual Ability Classification System. The results will be published and evidence found may contribute to the use of transcranial stimulation for this population. TRIAL REGISTRATION: ReBEC RBR-6V4Y3K . Registered on 11 February 2015.

Focal Muscle Vibration Improves Gait in Parkinson's Disease: A Pilot Randomized, Controlled Trial.

BACKGROUND: In Parkinson's disease (PD), gait disorders lead to increased risk of falls and patients' reduced participation and independence. Several observations suggest that a single session of focal muscle vibration (fMV) applied to trunk or lower limb muscles during gait may improve several gait variables in patients with PD. The possible long-term beneficial effects of repetitive sessions of fMV (r-fMV) on gait of patients with PD have been investigated. METHODS: A randomized, controlled trial study has been conducted in an outpatient rehabilitation department. Twenty patients with PD diagnosis have been randomized in two groups: "real" or "sham" r-fMV application to quadriceps and paraspinal muscles in patients with PD. Gait was evaluated with objective gait analysis, and a number of variables, including velocity, step length, stride length, percentage of stance, double support duration, cadence, swing velocity, and step width, have been measured. Gait analysis was performed before and 24 hours and 1 and 3 weeks after r-fMV. RESULTS: After real, but not sham, r-fMV, patients with PD had significant gait improvement as a result of increased walking velocity and stride length. The r-fMV-induced beneficial after effects lasted at least 1 week after the end of stimulation. CONCLUSIONS: Data emerging from our pilot randomized, controlled trial study suggest that r-fMV may improve gait disorders in patients with PD. r-fMV might be a feasible, safe approach for possibly improving gait disorders in patients with PD and might enhance the impact of specific rehabilitation programs in PD.

Age-Related Cortical Thickness Reduction in Non-Demented Down's Syndrome Subjects.

BACKGROUND AND PURPOSE: The aim of this study was to investigate the characteristic pattern of age-related cortical thinning in patients with Down Syndrome (DS), as assessed by MRI and automatic cortical thickness measurements. METHODS: Ninety-one non-demented subjects with DS (range 11-53 years) were examined using a 1.5 T scanner. MRI-based quantification of cortical thickness was performed using FreeSurfer software package., The Pearson product-moment correlation coefficient between age and mean cortical thickness was evaluated for all subjects participating in the study. RESULTS: A significant negative correlation between cortical thickness and age was found bilaterally in the frontal, temporal, parietal and cingulate gyrus. Specific investigation of cerebral lobes showed a more evident involvement of the frontal one, compared to others. Moreover, the age related reduction of cortical thickness appeared to be more significant and rapid in patients between 20 and 30 years of age. CONCLUSIONS: Our findings showed that Down Syndrome subjects are affected by a diffuse cortical thinning. The involvement of cortical structures can be observed at an earlier age than previous studies have reported.

Widespread cerebellar transcriptome changes in Ts65Dn Down syndrome mouse model after lifelong running.

Our previous study showed an improvement in locomotor deficits after voluntary lifelong running in Ts65Dn mice, an animal model for Down syndrome (DS). In the present study, we employed mouse microarrays printed with 55,681 probes in an attempt to identify molecular changes in the cerebellar transcriptome that might contribute to the observed behavioral benefits of voluntary long-term running in Ts65Dn mice. Euploid mice were processed in parallel for comparative purposes in some analyses. We found that running significantly changed the expression of 4,315 genes in the cerebellum of Ts65Dn mice, over five times more than in euploid animals, up-regulating 1,991 and down-regulating 2,324 genes. Functional analysis of these genes revealed a significant enrichment of 92 terms in the biological process category, including regulation of biosynthesis and metabolism, protein modification, phosphate metabolism, synaptic transmission, development, regulation of cell death/apoptosis, protein transport, development, neurogenesis and neuron differentiation. The KEGG pathway database identified 18 pathways that are up-regulated and two that are down-regulated by running that were associated with learning, memory, cell signaling, proteolysis, regeneration, cell cycle, proliferation, growth, migration, and survival. Of six mRNA protein products we tested by immunoblotting, four showed significant running-associated changes in their levels, the most prominent in glutaminergic receptor metabotropic 1, and two showed changes that were close to significant. Thus, unexpectedly, our data point to the high molecular plasticity of Ts65Dn mouse cerebellum, which translated into humans with DS, suggests that the motor deficits of individuals with DS could markedly benefit from prolonged exercise.

The Parkinsonian Gait Spatiotemporal Parameters Quantified by a Single Inertial Sensor before and after Automated Mechanical Peripheral Stimulation Treatment.

This study aims to evaluate the change in gait spatiotemporal parameters in subjects with Parkinson's disease (PD) before and after Automated Mechanical Peripheral Stimulation (AMPS) treatment. Thirty-five subjects with PD and 35 healthy age-matched subjects took part in this study. A dedicated medical device (Gondola) was used to administer the AMPS. All patients with PD were treated in off levodopa phase and their gait performances were evaluated by an inertial measurement system before and after the intervention. The one-way ANOVA for repeated measures was performed to assess the differences between pre- and post-AMPS and the one-way ANOVA to assess the differences between PD patients and the control group. Spearman's correlations assessed the associations between patients with PD clinical status (H&Y) and the percentage of improvement of the gait variables after AMPS (α < 0.05 for all tests). The PD group had an improvement of 14.85% in the stride length; 14.77% in the gait velocity; and 29.91% in the gait propulsion. The correlation results showed that the higher the H&Y classification, the higher the stride length percentage of improvement. The treatment based on AMPS intervention seems to induce a better performance in the gait pattern of PD patients, mainly in intermediate and advanced stages of the condition.

Long-term effects of automated mechanical peripheral stimulation on gait patterns of patients with Parkinson's disease.

New treatments based on peripheral stimulation of the sensory-motor system have been inspiring new rehabilitation approaches in Parkinson's disease (PD), especially to reduce gait impairment, levodopa washout effects, and the incidence of falls. The aim of this study was to evaluate the change in gait and the clinical status of PD patients after six sessions of a treatment based on automated mechanical peripheral stimulation (AMPS). Eighteen patients with PD and 15 age-matched healthy individuals (control group) participated in this study. A dedicated medical device delivered the AMPS. PD patients were treated with AMPS six times once every 4 days. All PD patients were treated in the off-levodopa phase and were evaluated with gait analysis before and after the first intervention (acute phase), after the sixth intervention, 48 h after the sixth intervention, and 10 days after the end of the treatment. To compare the differences among the AMPS interventions (pre, 6 AMPS, and 10 days) in terms of clinical scales, a t-test was used (α≤0.05). In addition, to compare the differences among the AMPS interventions (pre, post, 6 AMPS, 48 h and 10 days), the gait spatiotemporal parameters were analyzed using the Friedman test and the Bonferroni post-hoc test (α≤0.05). Also, for comparisons between the PD group and the control group, the gait spatiotemporal parameters were analyzed using the Mann-Whitney test and the Bonferroni post-hoc test (α≤0.05). The results of the study indicate that the AMPS treatment has a positive effect on bradykinesia because it improves walking velocity, has a positive effect on the step and stride length, and has a positive effect on walking stability, measured by the increase in stride length. These results are consistent with the improvements measured with clinical scales. These findings indicate that AMPS treatment seems to generate a more stable walking pattern in PD patients, reducing the well-known gait impairment that is typical of PD; regular repetition every 4 days of AMPS treatment appears to be able to improve gait parameters, to restore rhythmicity, and to reduce the risk of falls, with benefits maintained up to 10 days after the last treatment. The trial was registered online at ClinicalTrials.gov (number identifier: NCT0181528).

Foot pressure distribution in children with cerebral palsy while standing.

Foot deformity is a major component of impaired functioning in cerebral palsy (CP). While gait and balance issues related to CP have been studied extensively, there is little information to date on foot-ground interaction (i.e. contact area and plantar pressure distribution). This study aimed to characterize quantitatively the foot-ground contact parameters during static upright standing in hemiplegia and diplegia. We studied 64 children with hemiplegia (mean age 8.2 years; SD 2.8 years) and 43 with diplegia (mean age 8.8 years; SD 2.3 years) while standing on both legs statically on a pressure sensitive mat. We calculated pressure data for the whole foot and sub-regions (i.e. rearfoot, midfoot and forefoot) and average contact pressure. The Arch Index (AI) served for classifying the feet as flat, normal or cavus feet. The data were compared with those from a sample of age- and gender-matched participants (control group, 68 children). Most of the feet showed very high AI values, thus indicating a flat foot. This deformity was more common in diplegia (74.4%) than in hemiplegia (54.7%). In both diplegic and hemiplegic children, average plantar pressure was significantly increased in the forefoot and midfoot and decreased in the rearfoot (p<0.001). The present data indicate an increased load on the front parts of the foot, which may be due to plantarflexor overactivity or knee flexion, combined with an increased incidence of low foot arches. As a low foot arch does not necessarily increase forefoot load, this deformity can be regarded as secondary.

The effects of neuromuscular taping on gait walking strategy in a patient with joint hypermobility syndrome/Ehlers-Danlos syndrome hypermobility type.

OBJECTIVE: In this case study, biomechanical alterations induced by neuromuscular taping (NMT) were quantified, during walking, in a patient with joint hypermobility syndrome/Ehlers-Danlos syndrome hypermobility type (JHS/EDS-HT). METHODS: A female JHS/EDS-HT patient underwent NMT applications over the low back spine and bilaterally to the knee. Quantitative gait analyses were collected before the NMT application and at the end of the treatment (2 weeks after the first application of NMT). RESULTS: At the end of treatment following the NMT application, left step length showed improvements in cadence and velocity, the left knee showed a reduction in its flexed position at initial contact, and the right ankle joint improved its position at initial contact and in the swing phase. Improvements were also found in kinetics, in terms of the ankle moment and power. CONCLUSIONS: Results show that NMT seems to be a promising low-cost intervention for improving gait strategy in patients with JHS/EDS-HT. Further investigations are needed to assess the effects of this treatment intervention on pathological symptoms.

Age effects on cortical thickness in young Down's syndrome subjects: a cross-sectional gender study.

INTRODUCTION: The aim of this study was to determine differences in the characteristic pattern of age-related cortical thinning in men and women with Down's syndrome (DS) by means of MRI and automatic cortical thickness measurements and a cross-sectional design, in a large cohort of young subjects. METHODS: Eighty-four subjects with DS, 30 females (11-35 years, mean age ± SD = 22.8 ± 5.9) and 54 males (11-35 years, mean age ± SD = 21.5 ± 6.5), were examined using a 1.5-T scanner. MRI-based quantification of cortical thickness was performed using FreeSurfer software package. For all subjects participating in the study, the Pearson product-moment correlation coefficient between age and mean cortical thickness values has been evaluated. RESULTS: A significant negative correlation between cortical thickness and age was found in female DS subjects, predominantly in frontal and parietal lobes, bilaterally. In male DS subjects, a significant negative correlation between cortical thickness and age was found in the right fronto-temporal lobes and cingulate regions. Whole brain mean cortical thickness values were significantly negative correlated with age only in female DS subjects. CONCLUSIONS: Females with Down's syndrome showed a strong correlation between cortical thickness and age, already in early age. We suggest that the cognitive impairment due to hormonal deficit in the postmenopausal period could be emphasized by the early structural decline of gray matter in female DS subjects.

Gait pattern in lean and obese adolescents.

Obesity is the most common chronic disorder in children and adolescents. As walking is the most common daily task and is recommended for weight management, quantifying how obesity affects the biomechanics of gait provides important insight into the relationship between metabolic and mechanical energetics, mechanical loading and associated risk for musculoskeletal injury. This study quantitatively compared gait in 12 obese and 10 lean adolescents. Obese adolescents showed longer stance duration, excessive hip flexion during the whole gait cycle and an increased hip movement in the frontal plane compared with lean participants. In the obese, the knee was slightly extended in stance phase and the ankle was in a plantar flexed position at initial contact and at toe-off, with a greater ankle range of motion. Kinetic data showed higher values of maximum power generated at hip level during the stance phase; ankle power displayed a higher absorption at initial stance and higher values of power generation in the terminal stance. Because obese adolescents are encouraged to walk to increase their physical activity and energy expenditure level, injury prevention and rehabilitative programmes should take our findings into consideration and include specific strengthening of the lower limb proximal and distal muscles, together with weight loss and reconditioning interventions.

Effects of obesity on gait pattern in young individuals with Down syndrome.

In individuals with Down syndrome (DS), the prevalence of obesity is widespread; despite this, there are no experimental studies on the effect of obesity on gait strategy in DS individuals. The aim of this study is to assess the clinical gait analysis of a group of obese individuals with DS and a group of nonobese individuals with DS to determine whether obesity produces a different gait pattern in these participants. In addition, although females and males share a similar mass, they are characterized by different fat distribution and/or accumulation; thus, the presence of differences between females and males within the two DS groups was investigated. Gait analysis data of a group of 78 young individuals with DS and 20 normal-weight participants in the 5-18-year age range were considered. Among DS individuals, 40 were classified as obese (obese DS group), whereas 38 were classified as normal weight (nonobese groups). A three-dimensional gait analysis was carried out using an optoelectronic system, force platforms and video recording. Spatiotemporal, kinematic and kinetic parameters were identified and calculated for each participant. Our results show that most of the parameters were similar in the two groups of DS participants; the only differences were in terms of stance duration, longer in the obese DS group and dorsiflexion ability during the swing phase, which was limited in the obese DS group. The two DS groups were significantly different in terms of ankle stiffness (Ka index): both groups were characterized by reduced values compared with the control group, but the obese group presented lower values with respect to nonobese participants. The data showed that females were characterized by significant modifications of gait pattern compared with males in both groups, in particular, at proximal levels, such as the hip and the pelvis. Our findings indicate that the presence of obesity exerts effects on gait pattern in DS individuals and in particular on ankle joint stiffness. These results may have special clinical relevance; the biomechanical comparison of gait in young obese and nonobese DS individuals may provide a basis for developing either specific or common rehabilitative strategies.

Quantification of long-term effects of botulinum injection in a case of cerebral palsy affecting the upper limb movement.

OBJECTIVE: The aim of this work was to put into evidence the long-lasting modification induced by botulinum toxin injection and rehabilitative treatment on motor control. METHODS: In this contribution, we report the case of a female child showing hemiplegia, due to cerebral palsy. She underwent botulinum injection, followed by physical and occupational therapy. We quantified the biomechanical, cerebral and occupational aspects of her impaired upper limb, also dynamically, with respect to her pre- and post-treatment condition. RESULTS: Small long-lasting improvements--induced on biomechanics by botulinum injection--triggered wide cerebral modification, well reflected in improved contextual movements and motor strategy. CONCLUSION: These results provide evidences that small modifications in the end-effector performance often imply cerebral modifications and improvement in finalized motor strategy.

A cervical flexion-extension MRI study in Down syndrome.

OBJECTIVE: To assess what kind of information MR examination in flexed and extended positions provides in Down syndrome subjects with suspected cranio-cervical instability. METHODS: Between 2005 and 2008, 35 subjects with DS were recruited in the study. Ethics committee approval was granted and a signed informed consent was obtained from the parents. All the subjects were affected by hypotonic status and ligament laxity established by clinical evaluation, but were asymptomatic about focal neurological symptoms due to medullar damage caused by cranio-cervical instability. Each patient underwent lateral supine radiographs and MR imaging in the neutral, active flexed and extended positions. For evaluating the atlanto-axial and atlanto-occipital joint stability, multiple measurements were calculated. RESULTS: A significant reduction of anterior subarachnoid space in flexed position was evident in DS subjects compared to healthy controls in neutral and flexed positions. Both, space available for cord and ligamentous thickness showed significant differences between DS subjects and healthy controls. In DS subjects with occipito-cervical instability, the anterior subarachnoidal space reduction was significantly reduced in flexed position. CONCLUSIONS: In DS subjects with asymptomatic cranio-cervical instability, anterior subarachnoidal evaluation and ligamentous status could add new information about the risk of spinal cord damage.

Foot type analysis based on electronic pedobarography data in individuals with joint hypermobility syndrome/Ehlers-Danlos syndrome hypermobility type during upright standing.

BACKGROUND: Joint hypermobility syndrome/Ehlers-Danlos syndrome hypermobility type (JHS/EDS-HT) is a rheumatologic condition characterized by generalized joint hypermobility and musculoskeletal and nonmusculoskeletal findings related to congenital laxity of connective tissue. Because foot pain and other foot problems are reported to make daily life problematic to manage for individuals with JHS/EDS-HT, and thanks to the availability of modern technology, the aim of the present study was to quantitatively characterize foot type in individuals with JHS/EDS-HT during upright standing. METHODS: Forty feet of 20 women with JHS/EDS-HT (mean ± SD age, 36.03 ± 14.01 years) were assessed clinically and with a pressure-sensitive mat during upright standing. RESULTS: Forty-five percent of feet had a high arch (pes cavus), 27.5% had a normal arch, and 27.5% had a low arch (pes planus or flatfoot). CONCLUSIONS: From a clinical perspective, the characterization of foot type in JHS/EDS-HT is important to identify, develop, and enhance the rehabilitative options. An understanding of the relationship between pes cavus and foot pain in these patients could, in fact, improve the clinical management of these patients.

Effects of phenobarbital and levetiracetam on PR and QTc intervals in patients with post-stroke seizure.

BACKGROUND AND OBJECTIVES: Sudden unexplained/unexpected death (SUDEP) is related to high mortality in patients with epilepsy. The prolongation of QT interval, involved in cardiac arrhythmia-related SUDEP, may be precipitated by antiepileptic drugs (AEDs). In this study, we evaluated the effects of phenobarbital and levetiracetam on PR-QTc intervals in patients with post-stroke seizures. METHODS: We performed an open-label, parallel group, prospective, multicenter study between June 2009 and December 2013 in patients older than 18 years of age with a clinical diagnosis of post-stroke seizure and treated with phenobarbital or levetiracetam. In order to exclude a role of cerebral post-stroke injury on modulation of PR and QTc intervals, patients with cerebral post-stroke injury and without seizures were also enrolled as controls. RESULTS: Interictal electrocardiography analysis revealed no significant difference in PR interval between patients treated with an AED (n = 49) and control patients (n = 50) (181.25 ± 12.05 vs. 182.4 ± 10.3 ms; p > 0.05). In contrast, a significantly longer QTc interval was recorded in patients treated with an AED compared with control patients (441.2 ± 56.6 vs. 396.8 ± 49.3 ms; p < 0.01). Patients treated with phenobarbital showed a significantly longer QTc interval than patients treated with levetiracetam (460.0 ± 57.2 vs. 421.5 ± 50.1 ms; p < 0.05). CONCLUSIONS: The study reported that in patients with late post-stroke seizures, phenobarbital prolonged QTc interval more so than levetiracetam.

Mechanical energy assessment of adult with Down syndrome during walking with obstacle avoidance.

The aim of this study is analyzing the differences between plane walking and stepping over an obstacle for two groups of healthy people and people with Down syndrome and then, evaluating the movement efficiency between the groups by comprising of their mechanical energy exchanges. 39 adults including two groups of 21 people with Down syndrome (age: 21.6 ± 7 years) and 18 healthy people (age: 25.1 ± 2.4 years) participated in this research. The test has been done in two conditions, first in plane walking and second in walking with an obstacle (10% of the subject's height). The gait data were acquired using quantitative movement analysis, composed of an optoelectronic system (Elite2002, BTS) with eight infrared cameras. Mechanical energy exchanges are computed by dedicated software and finally the data including spatiotemporal parameters, mechanical energy parameters and energy recovery of gait cycle are analyzed by statistical software to find significant differences. Regards to spatiotemporal parameters velocity and step length are lower in people with Down syndrome. Mechanical energy parameters particularly energy recovery does not change from healthy people to people with Down syndrome. However, there are some differences in inter-group through plane walking to obstacle avoidance and it means people with Down syndrome probably use their residual abilities in the most efficient way to achieve the main goal of an efficient energy recovery.