Our motor system allows us to generate an enormous breadth of voluntary actions, but it remains unclear whether and how much motor skill translates across tasks. For example, if an individual is good at gross motor control, are they also good at fine motor control? Previous research about the generalization across motor skills has been equivocal. Here, we compare human performance across five different motor skills.
View Article and Find Full Text PDFWhile many areas of medicine have benefited from the development of objective assessment tools and biomarkers, there have been comparatively few improvements in techniques used to assess brain function and dysfunction. Brain functions such as perception, cognition, and motor control are commonly measured using criteria-based, ordinal scales which can be coarse, have floor/ceiling effects, and often lack the precision to detect change. There is growing recognition that kinematic and kinetic-based measures are needed to quantify impairments following neurological injury such as stroke, in particular for clinical research and clinical trials.
View Article and Find Full Text PDFBackground: Cognitive and motor function must work together quickly and seamlessly to allow us to interact with a complex world, but their integration is difficult to assess directly. Interactive technology provides opportunities to assess motor actions requiring cognitive control.
Objective: To adapt a reverse reaching task to an interactive robotic platform to quantify impairments in cognitive-motor integration following stroke.
Background: Robotic technologies for neurological assessment provide sensitive, objective measures of behavioural impairments associated with injuries or disease such as stroke. Previous robotic tasks to assess proprioception typically involve single limbs or in some cases both limbs. The challenge with these approaches is that they often rely on intact motor function and/or working memory to remember/reproduce limb position, both of which can be impaired following stroke.
View Article and Find Full Text PDFThe emotional and physical toll on caregivers of cancer patients is well documented, but research evaluating the financial burdens and time commitments of caregivers is limited. We suspected that the rural location of our cancer center would intensify these burdens for caregivers. We conducted a prospective trial to assess the out-of-pocket expenses and time commitment of caregivers of hematopoietic stem cell transplantation recipients within the first 4 weeks after discharge from the hospital from a National Cancer Institute (NCI)-designated comprehensive cancer center.
View Article and Find Full Text PDFBackground: Motor impairment after stroke interferes with performance of everyday activities. Upper limb spasticity may further disrupt the movement patterns that enable optimal function; however, the specific features of these altered movement patterns, which differentiate individuals with and without spasticity, have not been fully identified. This study aimed to characterize the kinematic and proprioceptive deficits of individuals with upper limb spasticity after stroke using the Kinarm robotic exoskeleton.
View Article and Find Full Text PDFBackground: The use of integrated robotic technology to quantify the spectrum of motor symptoms of Parkinson's Disease (PD) has the potential to facilitate objective assessment that is independent of clinical ratings. The purpose of this study is to use the KINARM exoskeleton robot to (1) differentiate subjects with PD from controls and (2) quantify the motor effects of dopamine replacement therapies (DRTs).
Methods: Twenty-six subjects (Hoehn and Yahr mean 2.
: Primary myelofibrosis (PMF) is a clonal hematopoietic stem cell disorder characterized by fibrosis of the marrow cavity, marked megakaryocyte atypia and progressive cytopenias. Although thrombosis predominates, bleeding is the primary manifestation in up to 20% of patients and may be life-threatening. In this report, we document restoration of megakaryocyte and platelet structure and function in PMF after allogeneic hematopoietic cell transplantation (HCT).
View Article and Find Full Text PDFForage availability and predation risk interact to affect habitat use of ungulates across many biomes. Within sky-island habitats of the Mojave Desert, increased availability of diverse forage and cover may provide ungulates with unique opportunities to extend nutrient uptake and/or to mitigate predation risk. We addressed whether habitat use and foraging patterns of female mule deer () responded to normalized difference vegetation index (NDVI), NDVI rate of change (green-up), or the occurrence of cougars ().
View Article and Find Full Text PDFTumor hypoxia is a negative prognostic factor that is implicated in oncogenic signal activation, immune escape, and resistance to treatment. Identifying the mechanistic role of hypoxia in immune escape and resistance to immune-checkpoint inhibitors may aid the identification of therapeutic targets. We and others have shown that V-domain Ig suppressor of T-cell activation (VISTA), a negative checkpoint regulator in the B7 family, is highly expressed in the tumor microenvironment in tumor models and primary human cancers.
View Article and Find Full Text PDFBackground: Robotic technologies to measure human behavior are emerging as a new approach to assess brain function. Recently, we developed a robot-based postural Load Task to assess corrective responses to mechanical disturbances to the arm and found impairments in many participants with stroke compared to a healthy cohort (Bourke et al, J NeuroEngineering Rehabil 12: 7, 2015). However, a striking feature was the large range and skewed distribution of healthy performance.
View Article and Find Full Text PDFExtracorporeal photopheresis (ECP) is an established therapy for the treatment of graft-versus-host-disease (GVHD) following an allogeneic stem cell transplant. We performed a prospective analysis of patients receiving ECP treatment for GVHD to identify a clinical pathway and resource utilization of this process. The cohort included consecutive allogeneic stem cell recipients with GVHD.
View Article and Find Full Text PDFCutaneous mechanoreceptors in the anterior lower leg and foot dorsum provide important information about contact with objects and movement at the knee and ankle. This cutaneous feedback contributes to static and dynamic balance control. We conducted experiment 1 to determine the effects of ageing on anterior lower leg cutaneous feedback.
View Article and Find Full Text PDFBackground: Spasticity is a common sequela of stroke. Traditional assessment methods include relatively coarse scales that may not capture all characteristics of elevated muscle tone. Thus, the aim of this study was to develop a tool to quantitatively assess post-stroke spasticity in the upper extremity.
View Article and Find Full Text PDFAn important aspect of motor control is the ability to perform tasks with the upper limbs while maintaining whole body balance. However, little is known about the coordination of upper limb voluntary and whole body postural control after mechanical disturbances that require both upper limb motor corrections to attain a behavioral goal and lower limb motor responses to maintain whole body balance. The present study identified the temporal organization of muscle responses and center of pressure (COP) changes following mechanical perturbations during reaching.
View Article and Find Full Text PDFBackground: Stroke can affect our ability to perform daily activities, although it can be difficult to identify the underlying functional impairment(s). Recent theories highlight the importance of sensory feedback in selecting future motor actions. This selection process can involve multiple processes to achieve a behavioural goal, including selective attention, feature/object recognition, and movement inhibition.
View Article and Find Full Text PDFIntroduction: Flexor hallucis longus (FHL) tendon transfer to the calcaneus is commonly used in the surgical treatment of chronic Achilles tendinopathy. This study assesses the integrity of FHL tendon biotenodesis screw fixation with respect to 2 variables: incorporation of a terminal whipstitch and tunnel depth.
Materials And Methods: A total of 60 fresh-frozen cadaver FHL tendons and 28 calcanei were harvested for analysis in 4 sets of fixation constructs; 14 whipstitched tendons were compared against their nonwhipstitched paired tendon via pull-out strength load testing, and 16 tendon pairs were randomized for fixation in either a full-depth tunnel (bicortical) or a 25-mm partial tunnel (unicortical).
One of the major goals of hemoglobinopathy research has been to devise improved pharmacologic strategies for the induction of fetal hemoglobin (HbF) in people with sickle cell disease and β-thalassemia. In this issue of Blood, Dulmovits and colleagues report that pomalidomide, a drug approved by the US Food and Drug Administration (FDA) for treatment of multiple myeloma, induces HbF production by decreasing levels of several key transcriptional repressors of fetal globin gene expression. In addition, they show that pomalidomide induces HbF in differentiating erythroid cells from people with sickle cell disease and in myeloma patients.
View Article and Find Full Text PDFBackground: About 1 in 7 of all hospitalized patients is readmitted within 30 days of discharge. The cost of readmissions is significant, with Medicare readmissions alone costing the health care system an estimated $28 billion a year.
Objective: To identify the rates of and causes for readmission within 100 days of patients receiving a hematopoietic stem cell transplant.
Humans possess an impressive ability to generate goal-oriented motor actions to move and interact with the environment. The planning and initiation of these body movements is supported by highly distributed cortical and subcortical circuits. Recent studies, inspired by advanced control theory, highlight similar sophistication when we make online corrections to counter small disturbances of the limb or altered visual feedback.
View Article and Find Full Text PDFThe present study investigated the perception of low frequency (3 Hz) vibration on the foot sole and its relationship to standing balance following short duration space flight in nine astronauts. Both 3 Hz vibration perception threshold (VPT) and standing balance measures increased on landing day compared to pre-flight. Contrary to our hypothesis, a positive linear relationship between these measures was not observed; however astronauts with the most sensitive skin (lowest 3 Hz VPT) were found to have the largest sway on landing day.
View Article and Find Full Text PDFFetal hemoglobin (HbF) induction can ameliorate the clinical severity of sickle cell disease and β-thalassemia. We previously reported that activation of the eukaryotic initiation factor 2α (eIF2α) stress pathway increased HbF through a posttranscriptional mechanism. In this study, we explored the underlying means by which salubrinal, an activator of eIF2α signaling, enhances HbF production in primary human erythroid cells.
View Article and Find Full Text PDFSkin sensory input from the foot soles is coupled with vestibular input to facilitate body orientation in a gravitational environment. Anecdotal observations suggest that foot sole skin becomes hypersensitive following space flight. The veritable level of skin sensitivity and its impact on postural disequilibrium observed post space flight have not been documented.
View Article and Find Full Text PDFIncreased fetal hemoglobin (HbF) expression is beneficial for β-hemoglobinopathy patients; however, current inducing agents do not possess the ideal combination of efficacy, safety and ease of use. Better understanding the mechanisms involved in γ-globin gene induction is critical for designing improved therapies, as no complete mechanism for any inducing agent has been identified. Given the cytotoxic nature of most known inducing drugs, we hypothesized that γ-globin is a cell stress response gene, and that induction occurs via activation of cell stress signaling pathways.
View Article and Find Full Text PDFParoxysmal nocturnal hemoglobinuria (PNH) is a rare hematological disorder that is often suspected in a patient presenting with non-immune hemolytic anemia associated with pancytopenia or venous thrombosis. This disorder is a consequence of acquired somatic mutations in the phosphatidylinositol glycan class A (PIG-A) gene in the hematopoietic stem cells (HSC) of patients. The presence of these mutations leads to production of blood cells with decreased glycosyl phosphatidylinositol-anchored cell surface proteins, making red blood cells derived from the clone more sensitive to complement mediated hemolysis.
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