47 research outputs found
Age-Related Attenuation of Dominant Hand Superiority
The decline of motor performance of the human hand-arm system with age is well-documented. While dominant hand performance is superior to that of the non-dominant hand in young individuals, little is known of possible age-related changes in hand dominance. We investigated age-related alterations of hand dominance in 20 to 90 year old subjects. All subjects were unambiguously right-handed according to the Edinburgh Handedness Inventory. In Experiment 1, motor performance for aiming, postural tremor, precision of arm-hand movement, speed of arm-hand movement, and wrist-finger speed tasks were tested. In Experiment 2, accelerometer-sensors were used to obtain objective records of hand use in everyday activities
Age-dependent motor unit remodelling in human limb muscles.
Voluntary control of skeletal muscle enables humans to interact with and manipulate the environment. Lower muscle mass, weakness and poor coordination are common complaints in older age and reduce physical capabilities. Attention has focused on ways of maintaining muscle size and strength by exercise, diet or hormone replacement. Without appropriate neural innervation, however, muscle cannot function. Emerging evidence points to a neural basis of muscle loss. Motor unit number estimates indicate that by age around 71 years, healthy older people have around 40Â % fewer motor units. The surviving low- and moderate-threshold motor units recruited for moderate intensity contractions are enlarged by around 50Â % and show increased fibre density, presumably due to collateral reinnervation of denervated fibres. Motor unit potentials show increased complexity and the stability of neuromuscular junction transmissions is decreased. The available evidence is limited by a lack of longitudinal studies, relatively small sample sizes, a tendency to examine the small peripheral muscles and relatively few investigations into the consequences of motor unit remodelling for muscle size and control of movements in older age. Loss of motor neurons and remodelling of surviving motor units constitutes the major change in ageing muscles and probably contributes to muscle loss and functional impairments. The deterioration and remodelling of motor units likely imposes constraints on the way in which the central nervous system controls movements
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Cervical Spine Injury in Burned Trauma Patients: Incidence, Predictors, and Outcomes.
Cervical spine injuries (CIs) carry significant morbidity and mortality; hence, cervical spine immobilization is used liberally in trauma patients, including burns. The incidence, predictors, and outcomes of CI in burn patients are unknown. A retrospective cohort from the National Trauma Data Bank between 2007 and 2012 included all burned patients with and without CI. Predictors of CI were identified by logistic regression. Outcomes with and without CI were compared with Wilcoxon rank sum test. A total of 94,964 patients were identified with burn injuries. The incidence of CI was 0.79% (n = 745). Mechanism of injury, age, and injury severity score (ISS) were significant predictors of CI. Odds of CI were 109.4 (95% CI: 61.2-195.3, P < .0001) for motor vehicle injury, 87.8 (95% CI: 47.0-164.0, P < .0001) for falls, 1.2 (95% CI: 0.6-2.3, P = .66) for fire/flame, and 2.4 (95% CI: 1.0-5.5, P < .0001) for explosion compared with reference of hot object/substance. For every year increase in age, there were 1.02 higher odds of CI (95% CI: 1.01-1.02, P < .0001). For each point increase in ISS, there were 1.05 higher odds of CI (95% CI: 1.04-1.05, P < .0001). Patients with CI had higher mortality (10.3% vs 2.9%, P < .0001), longer total length of stay (12.0 vs 2.0 days, P < .0001), intensive care unit length of stay (4.0 vs 0.0 days, P < .001), and ventilator days (1.0 vs 0.0 days, P < .0001). The incidence of CI in burn patients is low, especially when due to fire, flame, or scalds; however, CI is associated with higher mortality and worse outcomes
Causes of early mortality in pediatric trauma patients
BACKGROUND: Trauma is the leading cause of death in children, and most deaths occur within 24 hours of injury. A better understanding of the causes of death in the immediate period of hospital care is needed. METHODS: Trauma admissions 24 hours after arrival (69%). Traumatic brain injury was the most common cause of death (66%), followed by anoxia (9.7%) and hemorrhage (8%). Deaths from hemorrhage were most often in patients sustaining gunshot wounds (GSWs, 73% vs. 11% of all other deaths, p<0.0001), more likely to occur early (100% vs. 50% of all other deaths, p=0.0009), and all died within 6 hours of arrival. Death from hemorrhage was more common in adolescents (21.4% of children aged 13–17 vs. 6.3% of children aged 0–6, and 0% of children aged 7–12 p = 0.03). The highest case fatality rates were seen in hangings (38.5%) and GSWs (9.6%). CONCLUSIONS: Half of pediatric trauma deaths occurred within 24 hours. Death from hemorrhage was rare, but all occurred within 6 hours of arrival. This is a critical time for interventions for bleeding control to prevent death from hemorrhage in children. Analysis of these deaths can focus efforts on the urgent need for development of new hemorrhage control adjuncts in children
Fetal Surgery in the Primate 4.0: A New Technique 30 Years Later
IntroductionOpen fetal surgery requires a hemostatic hysterotomy that minimizes membrane separation. For over 30 years, the standard of care for hysterotomy in the gravid uterus has been the AutoSuture Premium Poly CS*-57 stapler.ObjectiveIn this study, we sought to test the feasibility of hysterotomy in a rhesus monkey model with the Harmonic ACE®+7 Shears.MethodsA gravid rhesus monkey underwent midgestation hysterotomy at approximately 90 days of gestation (2nd trimester; term = 165 ± 10 days) using the Harmonic ACE®+7 Shears. A two-layer uterine closure was completed and the dam was monitored by ultrasound intermittently throughout the pregnancy. At 58 days after hysterotomy (near term), a final surgery was performed to evaluate the uterus and hysterotomy site.ResultsA 3.5-cm hysterotomy was completed in 2 min 7 s. The opening was hemostatic and the membranes were sealed. Immediately after closure and throughout the pregnancy, ultrasound revealed intact membranes without separation and normal amniotic fluid levels. At term, the scar was well healed without signs of thinning or dehiscence.ConclusionsThe Harmonic ACE®+7 Shears produced a hemostatic midgestation hysterotomy with membrane sealing in the rhesus monkey model. Importantly, healing was acceptable
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A Decade of Experience with the Ovine Model of Myelomeningocele: Risk Factors for Fetal Loss
IntroductionThe ovine model is the gold standard large animal model of myelomeningocele (MMC); however, it has a high rate of fetal loss. We reviewed our experience with the model to determine risk factors for fetal loss.MethodsWe performed a retrospective review from 2009 to 2018 to identify operative factors associated with fetal loss (early fetal demise, abortion, or stillbirth). Operative risk factors included gestational age at operation, operative time, reduction of multiple gestations, amount of replaced amniotic fluid, ambient temperature, and method of delivery.ResultsMMC defects were created in 232 lambs with an overall survival rate of 43%. Of the 128 fetuses that died, 53 (42%) had demise prior to repair, 61 (48%) aborted, and 14 (11%) were stillborn. Selective reduction of multiple gestations in the same uterine horn was associated with increased fetal demise (OR 3.03 [95% CI 1.29-7.05], p = 0.01). Later gestational age at MMC repair and Cesarean delivery were associated with decreased abortion/stillbirth (OR 0.90 [95% CI 0.83-0.90], p = 0.03, and OR 0.37 [95% CI 0.16-0.31], p = 0.02), respectively.ConclusionAvoiding selective reduction, repairing MMC later in gestation, and performing Cesarean delivery decreases the rate of fetal loss in the ovine MMC model
In utero treatment of myelomeningocele with placental mesenchymal stromal cells - Selection of an optimal cell line in preparation for clinical trials.
BackgroundWe determined whether in vitro potency assays inform which placental mesenchymal stromal cell (PMSC) lines produce high rates of ambulation following in utero treatment of myelomeningocele in an ovine model.MethodsPMSC lines were created following explant culture of three early-gestation human placentas. In vitro neuroprotection was assessed with a neuronal apoptosis model. In vivo, myelomeningocele defects were created in 28 fetuses and repaired with PMSCs at 3 × 105 cells/cm2 of scaffold from Line A (n = 6), Line B (n = 7) and Line C (n = 5) and compared to no PMSCs (n = 10). Ambulation was scored as ≥13 on the Sheep Locomotor Rating Scale.ResultsIn vitro, Line A and B had higher neuroprotective capability than no PMSCs (1.7 and 1.8 respectively vs 1, p = 0.02, ANOVA). In vivo, Line A and B had higher large neuron densities than no PMSCs (25.2 and 27.9 respectively vs 4.8, p = 0.03, ANOVA). Line C did not have higher neuroprotection or larger neuron density than no PMSCs. In vivo, Line A and B had ambulation rates of 83% and 71%, respectively, compared to 60% with Line C and 20% with no PMSCs.ConclusionThe in vitro neuroprotection assay will facilitate selection of optimal PMSC lines for clinical use.Level of evidencen/a.Type of studyBasic science