Relationship between lower limb coordination and walking speed after stroke: an observational study.

BACKGROUND: Although lower limb muscle strength is associated with walking performance in people after stroke, even when there is good strength, walking speed may remain slower than normal, perhaps due to incoordination. OBJECTIVE: The aim of this study was to examine the relationship between walking speed and lower limb coordination in people with good strength after stroke. METHODS: An observational study was conducted with 30 people with stroke and 30 age-matched controls. Inclusion criteria for stroke were good lower limb strength (i.e., ≥Grade 4) and walking speed at >0.6m/s without aids in bare feet (with recruitment stratified so that walking speed was evenly represented across the range). Walking performance was measured as speed during the 10-m Walk Test and distance during the 6-min Walk Test. Coordination was measured using the Lower Extremity Motor Coordination Test and reported in taps/s. RESULTS: Stroke survivors walked at 1.00 (SD 0.26) m/s during the10-m Walk Test (64% of normal), walked 349 (SD 94) m during the 6-min Walk Test (68% of normal), and performed the Lower Extremity Motor Coordination Test at 1.20 (SD 0.34) taps/s with the affected side (64% of normal). Lower Extremity Motor Coordination Test scores for the affected side were statistically significantly correlated with walking performance in the 10-m Walk Test (r=0.42, p=0.02) and the 6-min Walk Test (r=0.50, p=0.01). CONCLUSION: Coordination was related to walking performance, suggesting that loss of coordination may contribute to slow walking in this group of stroke survivors with good strength. TRIAL REGISTRATION: ANZCTR12614000856617 (www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=366827).

Ischemic stroke related to intracranial branch atheromatous disease and comparison with large and small artery diseases.

BACKGROUND: The mechanism of ischemic stroke in intracranial branch atheromatous disease (BAD) is different from large artery atherothrombotic disease (LAD) or lacunar infarction (LACI). The concept of BAD is underused in clinical practice and research. METHODS: Patients admitted over 24-months with ischemic stroke caused by atherosclerotic disease were reviewed retrospectively and classified according to radiological±clinical criteria into LAD, BAD and LACI. The BAD cases were further divided into 5 BAD syndromes. Clinical characteristics, vascular risk factors, results of vascular workup and outcome among these subgroups were compared. RESULTS: 123 cases of LAD (17% of all stroke patients or 33% of all studied patients), 147 BAD (20% or 40%) and 102 LACI (14% or 27%) presented during the study period. Compared to LAD, BAD patients had milder neurological deficits, were less often diabetic and carotid stenosis was less common, while stenosis of the intracranial arteries was more frequent in BAD as compared with LACI patients. Outcome in BAD patients was intermediate between LAD and LACI. Comparisons among the BAD syndromes indicated they were homogenous conditions. CONCLUSIONS: BAD is the most prevalent ischemic stroke subtype in our cohort. The homogeneity among the BAD syndromes suggests they might represent a distinctive stroke entity.

Cloning and characterization of novel PDE4D isoforms PDE4D6 and PDE4D7.

We report here the cloning and characterization of two novel PDE4D isoforms, PDE4D6 and PDE4D7. PDE4D6 is a supershort form and PDE4D7 a long form of PDE4D. In addition, we have identified another novel long-form variant, PDE4D8, in silico. Like other isoforms, PDE4D6 and PDE4D7 are differentially expressed. Expression of PDE4D6 is restricted to brain whereas PDE4D7 is widely expressed in many tissues. Baculovirus-expressed recombinant PDE4D6 and PDE4D7 enzymes have high affinity for cyclic AMP (cAMP) and are inhibited by rolipram. The activity of PDE4D7, not PDE4D6, is elevated by a protein kinase A (PKA)-dependent mechanism, presumably through phosphorylation of the conserved PKA site in the upstream conserved region 1 (UCR1) domain. In agreement with early reports, human PDE4D6 and PDE4D7 are localized on genomic fragments of chromosome 5. Examination of the promoter regions reveals multiple CREB binding sites upstream of the starting methionine (Met) of each gene, suggesting that the cAMP/PKA signaling pathway may regulate transcriptional expression of PDE4D6 and PDE4D7.

Relations among physical activity, physical fitness, and self-perceived fitness in Hong Kong adolescents.

The relationships between physical fitness, activity, and self-perceived fitness in adolescents in Hong Kong were investigated. Regular physical activity patterns, self-perceptions of fitness, and health-related physical fitness were measured in 201 secondary school students (M age = 13.8 yr.). The battery of fitness tests measured cardiovascular capacity, flexibility, muscular strength, muscular endurance, and body fat composition. The boys had a higher self-perception of their own fitness and exercised more outside school than the girls. Participation in physical activity was related to cardiovascular capacity, muscular strength, and body composition. Linear regression analysis indicated that exercise activity and body composition explained a portion of variance in the subjects' self-perceived fitness. These findings highlight the connections between physical activity, fitness, and self-perception of fitness and consequently the need for understanding the concept for better health-promotion strategies.