•Step length asymmetry is common after non-traumatic transtibial amputation.•Split-belt treadmill walking improves gait asymmetry in other patient populations.•Gait adaptation in people with ...non-traumatic transtibial amputation is unclear.•Participants are capable of gait adaptation during split-belt treadmill walking.•Step length asymmetry is reduced with the split-belt treadmill protocol.
Between-limb step length asymmetry is common following transtibial amputation (TTA) and contributes to negative health consequences. There are limited evidence-based interventions targeting reduced gait asymmetry for people with TTA. Split-belt treadmill walking with asymmetrical belt speeds has successfully reduced gait asymmetry in other patient populations. However, individuals with non-traumatic TTA have critical health-related impairments that may influence the ability to respond to split-belt treadmill walking.
Do people with acquired, non-traumatic TTA adapt and retain a more symmetrical gait pattern in response to split-belt treadmill walking?
Step length asymmetry was measured during split-belt treadmill walking. Eight participants walked under two alternating belt speed conditions: symmetrical (3 sets; Baseline, TIED1, TIED2) and asymmetrical belt speeds (5 sets; SPLIT1–5). One-way repeated-measures ANOVA with post-hoc Tukey’s HSD tests were used to assess adaptation and short-term retention of step length symmetry. Adaptation was assessed as the level of asymmetry during TIED walking following repeated exposure to SPLIT walking. Retention was measured as the change in level of asymmetry during each set of SPLIT walking.
Significant adaptation to split-belt walking was observed from late Baseline to early TIED1 and early TIED2. Between-limb step length asymmetry decreased from late Baseline (5.3 ± 3.4) to early TIED1 (-9.4 ± 3.6) and this change was sustained between early TIED1 and early TIED2 (-11.2 ± 3.1) (ANOVA F = 73.043, p < .001). Adaptations were retained as step length asymmetry decreased from early SPLIT1 (48.5 ± 5.3) to early SPLIT3 (31.4 ± 3.5) to early SPLIT5 (23.9 ± 5.1) (ANOVA F = 35.284, p < .001).
Individuals with non-traumatic TTA are capable of gait adaptation to split-belt walking and short-term retention of adaptations after removal of the asymmetrical belt speeds. Adaptability of step length symmetry is possible without modification to the prosthetic limb. Split-belt walking should be tested as a potential intervention to help people with acquired, non-traumatic TTA increase between-limb step symmetry.
A single bout of high‐intensity exercise can augment off‐line gains in skills acquired during motor practice. It is currently unknown if the type of physical exercise influences the effect on motor ...skill consolidation. This study investigated the effect of three types of high‐intensity exercise following visuomotor skill acquisition on the retention of motor memory in 40 young (25.3 ±3.6 years), able‐bodied male participants randomly assigned to one of four groups either performing strength training (STR), circuit training (CT), indoor hockey (HOC) or rest (CON). Retention tests of the motor skill were performed 1 (R1h) and 24 h (R1d) post acquisition. For all exercise groups, mean motor performance scores decreased at R1h compared to post acquisition (POST) level; STR (P = 0.018), CT (P = 0.02), HOC (P = 0.014) and performance scores decreased for CT compared to CON (P = 0.049). Mean performance scores increased from POST to R1d for all exercise groups; STR (P = 0.010), CT (P = 0.020), HOC (P = 0.007) while performance scores for CON decreased (P = 0.043). Changes in motor performance were thus greater for STR (P = 0.006), CT (P < 0.001) and HOC (P < 0.001) compared to CON from POST to R1d. The results demonstrate that high‐intensity, acute exercise can lead to a decrease in motor performance assessed shortly after motor skill practice (R1h), but enhances offline effects promoting long‐term retention (R1d). Given that different exercise modalities produced similar positive off‐line effects on motor memory, we conclude that exercise‐induced effects beneficial to consolidation appear to depend primarily on the physiological stimulus rather than type of exercise and movements employed.
We present revised stellar properties for 172 K2 target stars that were identified as possible hosts of transiting planets during Campaigns 1-17. Using medium-resolution near-infrared spectra ...acquired with the NASA Infrared Telescope Facility/SpeX and Palomar/TripleSpec, we found that 86 of our targets were bona fide cool dwarfs, 74 were hotter dwarfs, and 12 were giants. Combining our spectroscopic metallicities with Gaia parallaxes and archival photometry, we derived photometric stellar parameters and compared them to our spectroscopic estimates. Although our spectroscopic and photometric radius and temperature estimates are consistent, our photometric mass estimates are systematically ΔM = 0.11 M (34%) higher than our spectroscopic mass estimates for the least massive stars (M ,phot < 0.4 M ). Adopting the photometric parameters and comparing our results to parameters reported in the Ecliptic Plane Input Catalog, our revised stellar radii are ΔR = 0.15 R (40%) larger, and our revised stellar effective temperatures are roughly ΔTeff = 65 K cooler. Correctly determining the properties of K2 target stars is essential for characterizing any associated planet candidates, estimating the planet search sensitivity, and calculating planet occurrence rates. Even though Gaia parallaxes have increased the power of photometric surveys, spectroscopic characterization remains essential for determining stellar metallicities and investigating correlations between stellar metallicity and planetary properties.
Levels of physical activity and variation in physical activity and sedentary time by place and person in European children and adolescents are largely unknown. The objective of the study was to ...assess the variations in objectively measured physical activity and sedentary time in children and adolescents across Europe.
Six databases were systematically searched to identify pan-European and national data sets on physical activity and sedentary time assessed by the same accelerometer in children (2 to 9.9 years) and adolescents (≥10 to 18 years). We harmonized individual-level data by reprocessing hip-worn raw accelerometer data files from 30 different studies conducted between 1997 and 2014, representing 47,497 individuals (2-18 years) from 18 different European countries.
Overall, a maximum of 29% (95% CI: 25, 33) of children and 29% (95% CI: 25, 32) of adolescents were categorized as sufficiently physically active. We observed substantial country- and region-specific differences in physical activity and sedentary time, with lower physical activity levels and prevalence estimates in Southern European countries. Boys were more active and less sedentary in all age-categories. The onset of age-related lowering or leveling-off of physical activity and increase in sedentary time seems to become apparent at around 6 to 7 years of age.
Two third of European children and adolescents are not sufficiently active. Our findings suggest substantial gender-, country- and region-specific differences in physical activity. These results should encourage policymakers, governments, and local and national stakeholders to take action to facilitate an increase in the physical activity levels of young people across Europe.
Contaminant mass discharge is a commonly applied tool to evaluate the environmental impact of contaminated sites on water resources. At large contaminated sites with heterogeneous sources, such as ...landfills, the number of wells available is often not sufficient, leading to a high uncertainty of mass discharge estimates. In this study, we tackle the uncertainty of the contaminant mass discharge due to low sampling densities by interpolating limited water‐sample data with the support of surface direct current resistivity and induced polarization geophysical data. The method relies on finding a conceptual link between the bulk conductivity imaged from geophysics and the contaminant concentrations. We investigate the link between (1) imaged bulk and electrical water conductivity, (2) water conductivity and conservative ionic species, (3) water conductivity and redox‐sensitive species, (4) water conductivity and semipersistent organic species, and (5) water conductivity and biodegradable organic compounds. The method successfully identify similarities between the distribution of the bulk conductivity and chloride and pharmaceutical compounds in a landfill leachate plume and between the bulk conductivity data and benzene and chlorinated ethenes for a contaminant plume from a former pharmaceutical factory. Contaminant concentrations were interpolated through regression kriging, using geophysical data as the dependent variable. The distribution of concentration determined with the novel method showed a lower mean relative estimation error than the traditional method of kriging only contaminant concentration data. At large sites, the method can improve contaminant mass discharge estimates, especially if surface geophysical measurements are integrated in the site investigation at an early stage.
Key Points
Surface direct current resistivity and induced polarization geophysical data can improve the interpolation of contaminant concentration data
The geophysics‐based method can improve estimation of contaminant mass discharge at large contaminated sites with low water‐sample densities
Surface geophysical data are affected by changes in inorganic species arising from a contaminant source or generated during biodegradation
Pediatric Hereditary Angioedema Christiansen, Sandra C.; Davis, Donna K.; Castaldo, Anthony J. ...
Clinical pediatrics,
09/2016, Letnik:
55, Številka:
10
Journal Article
Recenzirano
Hereditary angioedema (HAE) typically presents in childhood. Large gaps remain in our understanding of the natural history of HAE during childhood. We examined age of onset, delay in diagnosis, ...androgen exposure, and their influence on ultimate disease severity in a large cohort of patients with HAE. Median age of first swelling was 11 years with a median age at diagnosis of 19 years. Earlier onset of symptoms correlated with longer delays in diagnosis (P < .001) and predicted a more severe disease course, including increased number of attacks per year (P = .0009) and hospital admissions (P = .009). Earlier age of onset also significantly correlated with increased perceived HAE severity (P = .0002), negative overall life impact (P < .0001), and use of anabolic androgen. Our observations highlight the importance of early HAE diagnosis and suggest the necessity of a disease management plan once the diagnosis has been made.
The evolutionary relationship between two central major histocompatibility complex (MHC) genes, C4 and CYP21, was investigated by employing pulsed field gel electrophoresis (PFGE) and conventional ...restriction fragment length polymorphism (RFLP) analyses in human and nonhuman primates. Using Taq I in conjunction with C4 and CYP21 probes, it has been found that there are four major types of C4 genes defined by 7.0, 6.4, 6.0, and 5.4 kilobases (kb) Taq I fragments and two major types of CYP21 genes (3.7 and 3.2 kb fragments) in human and nonhuman primates including chimpanzee, gorilla, and orangutan. All of the eight possible combinations of C4 and CYP21 genes can be identified on one or more human ancestral haplotypes (AH). It is concluded that each of the major types of C4 and CYP21 (and each of the combinations between these) predated human speciation. PFGE analysis with Mlu I and Pvu I suggested that each C4+CYP21 segment has a specific length of 30-50 kb and that each AH carries one, two, three, or even more segments. In the case of C4, it is important to note that there is no simple relationship between the RFLP and the protein classifications. Thus, at least some of the expressed polymorphisms could be relatively recent in that they are carried by the same or different gene types. These findings are consistent with the hypothesis that MHC AHs have been formed from a large pool of specific genomic segments and that further haplospecific polymorphism has developed subsequently.
Summary
There is a close cross‐talk between complement, Toll‐like receptors (TLRs) and coagulation. The role of the central complement component 5 (C5) in physiological and pathophysiological ...hemostasis has not, however, been fully elucidated. This study examined the effects of C5 in normal hemostasis and in Escherichia coli‐induced coagulation and tissue factor (TF) up‐regulation. Fresh whole blood obtained from six healthy donors and one C5‐deficient individual (C5D) was anti‐coagulated with the thrombin inhibitor lepirudin. Blood was incubated with or without E. coli in the presence of the C5 inhibitor eculizumab, a blocking anti‐CD14 monoclonal antibody (anti‐CD14) or the TLR‐4 inhibitor eritoran. C5D blood was reconstituted with purified human C5. TF mRNA was measured by quantitative polymerase chain reaction (qPCR) and monocyte TF and CD11b surface expression by flow cytometry. Prothrombin fragment 1+2 (PTF1·2) in plasma and microparticles exposing TF (TF‐MP) was measured by enzyme‐linked immunosorbent assay (ELISA). Coagulation kinetics were analyzed by rotational thromboelastometry and platelet function by PFA‐200. Normal blood with eculizumab as well as C5D blood with or without reconstitution with C5 displayed completely normal biochemical hemostatic patterns. In contrast, E. coli‐induced TF mRNA and TF‐MP were significantly reduced by C5 inhibition. C5 inhibition combined with anti‐CD14 or eritoran completely inhibited the E. coli‐induced monocyte TF, TF‐MP and plasma PTF1·2. Addition of C5a alone did not induce TF expression on monocytes. In conclusion, C5 showed no impact on physiological hemostasis, but substantially contributed to E. coli‐induced procoagulant events, which were abolished by the combined inhibition of C5 and CD14 or TLR‐4.
Effect of eculizumab, anti‐CD14 or the TLR‐4 inhibitor eritoran on Escherichia coli (E. coli)‐induced monocyte tissue factor (TF) surface expression (a), tissue factor function in plasma microparticles (TF‐MP) (b) and prothrombin fragment 1+2 (PTF1·2) levels in plasma (c). Inhibition of C5 using eculizumab reduced the E. coli‐induced TF‐MP level. C5 inhibition combined with anti‐CD14 or eritoran completely inhibited the E. coli‐induced monocyte TF, TF‐MP and plasma PTF1·2.
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