Publications by authors named "Tansey K"

Approved in 2014 by the Food and Drug Administration (FDA) for use with a trained companion, personal powered exoskeletons (PPE) for individuals with spinal cord injury (SCI) provide an opportunity for the appropriate candidate to ambulate in their home and community. As an adjunct to wheeled mobility, PPE use allows those individuals who desire to ambulate the opportunity to experience the potential physiological and psychosocial benefits of assisted walking outside of a rehabilitation setting. There exists, however, a knowledge gap for clinicians regarding appropriate candidate selection for use, as well as who might benefit from ambulating with a PPE.

View Article and Find Full Text PDF

Study Design: Consensus process.

Objectives: To provide a reference for the Zone(s) of Partial Preservation (ZPP) in the 2019 International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) and analyze the initial impact of applicability of the revised ZPPs. Revisions include the use of ZPPs in selected incomplete injuries (in addition to prior use in sensorimotor complete injuries).

View Article and Find Full Text PDF

Neuromodulation via spinal stimulation has been investigated for improving motor function and reducing spasticity after spinal cord injury (SCI) in humans. Despite the reported heterogeneity of outcomes, few investigations have attempted to discern commonalities among individual responses to neuromodulation, especially the impact of stimulation frequencies. Here, we examined how exposure to continuous lumbosacral transcutaneous spinal stimulation (TSS) across a range of frequencies affects robotic torques and EMG patterns during stepping in a robotic gait orthosis on a motorized treadmill.

View Article and Find Full Text PDF
Article Synopsis
  • The study examined the reflexes of the soleus muscle in subjects with and without spinal cord injury during stepping activities.
  • Both groups showed step cycle modulation of the soleus H and PRM reflexes, but the modulation was less pronounced in those with spinal cord injuries.
  • Higher reflex amplitudes in the SCI group correlated with lower motor scores, suggesting that inadequate reflex modulation may indicate injury severity and reduced nerve regulation.
View Article and Find Full Text PDF

Research studies based on tractography have revealed a prominent reduction of asymmetry in some key white-matter tracts in schizophrenia (SCZ). However, we know little about the influence of common genetic risk factors for SCZ on the efficiency of routing on structural brain networks (SBNs). Here, we use a novel recall-by-genotype approach, where we sample young adults from a population-based cohort (ALSPAC:N genotyped = 8,365) based on their burden of common SCZ risk alleles as defined by polygenic risk score (PRS).

View Article and Find Full Text PDF
Article Synopsis
  • There is growing concern about military surgeons losing critical skills for wartime medical procedures, leading to the development of the KSA Clinical Readiness Program to assess clinician readiness in the military health system (MHS).
  • A revised methodology improved the assessment by focusing on key expeditionary orthopedic surgery procedures and adjusting categories and scores based on actual practices from 2017 to 2019.
  • Although there was a small decrease in overall credited procedures, the revision allowed for a more accurate alignment with essential surgical skills needed during deployments.
View Article and Find Full Text PDF
Article Synopsis
  • - The study analyzes major amputations in military health facilities (MTF) from 2017-2019 to understand how military surgeons can maintain critical wartime skills, particularly for amputations due to trauma.
  • - Out of 1,184 amputations identified, two MTFs accounted for almost half, with a significant number of traumatic amputations being conducted primarily on civilian patients.
  • - Findings suggest that civilian patient care is vital for increasing the complexity and volume of surgical cases, thus aiding military surgeons in preserving necessary skills for combat casualty care.
View Article and Find Full Text PDF

Gamma oscillations (30-90 Hz) have been proposed as a signature of cortical visual information processing, particularly the balance between excitation and inhibition, and as a biomarker of neuropsychiatric diseases. Magnetoencephalography (MEG) provides highly reliable visual-induced gamma oscillation estimates, both at sensor and source level. Recent studies have reported a deficit of visual gamma activity in schizophrenia patients, in medication naive subjects, and high-risk clinical participants, but the genetic contribution to such a deficit has remained unresolved.

View Article and Find Full Text PDF

Occupational exposure to whole-body vibration is associated with the development of musculoskeletal, neurological, and other ailments. Low back pain and other spine disorders are prevalent among those exposed to whole-body vibration in occupational and military settings. Although standards for limiting exposure to whole-body vibration have been in place for decades, there is a lack of understanding of whole-body vibration-associated risks among safety and healthcare professionals.

View Article and Find Full Text PDF

Background: Altered functional brain connectivity has been proposed as an intermediate phenotype between genetic risk loci and clinical expression of schizophrenia. Genetic high-risk groups of healthy subjects are particularly suited for the investigation of this proposition because they can be tested in the absence of medication or other secondary effects of schizophrenia.

Methods: Here, we applied dynamic functional connectivity analysis to functional magnetic resonance imaging data to reveal the reconfiguration of brain networks during a cognitive task.

View Article and Find Full Text PDF

A strategy of early extubation to noninvasive respiratory support in preterm infants could be boosted by the availability of a decision support tool for clinicians. Using the Heart Rate Characteristics index (HRCi) with clinical parameters, we derived and validated predictive models for extubation readiness and success.Peri-extubation demographic, clinical and HRCi data for up to 96 h were collected from mechanically ventilated infants in the control arm of a randomised trial involving eight neonatal centres, where clinicians were blinded to the HRCi scores.

View Article and Find Full Text PDF
Article Synopsis
  • Scientists studied the brain's outer layer, called the cerebral cortex, to learn how genes can affect its structure.
  • They looked at brain scans from over 51,000 people and found 199 important genetic markers that relate to how the cortex is shaped.
  • The study showed that these genetic markers are linked to different brain functions and conditions like thinking skills, sleep problems, and ADHD.
View Article and Find Full Text PDF

Electrical stimulation to segmental dorsal cutaneous nerves (DCNs) activates a nociceptive sensorimotor reflex and the same afferent stimulation also evokes blood pressure (BP) and heart rate (HR) responses in rats. To investigate the relationship between those cardiovascular responses and the activation of nociceptive afferents, we analyzed BP and HR responses to electrical stimulations at each DCN from T6 to L1 at 0.5 mA to activate A-fiber alone or 5 mA to activate both A- and C-fibers at different frequencies.

View Article and Find Full Text PDF

Electrical stimulations of dorsal cutaneous nerves (DCNs) at each lumbothoracic spinal level produce the bilateral cutaneus trunci muscle (CTM) reflex responses which consist of two temporal components: an early and late responses purportedly mediated by A and C fibers, respectively. We have previously reported central projections of DCN A and C fibers and demonstrated that different projection patterns of those afferent types contributed to the somatotopic organization of CTM reflex responses. Unilateral hemisection spinal cord injury (SCI) was made at T10 spinal segments to investigate the plasticity of early and late CTM responses 6 weeks after injury.

View Article and Find Full Text PDF

Traumatic brain injury is highly prevalent in the United States. However, despite its frequency and significance, there is little understanding of how the brain responds during injurious loading. A confounding problem is that because testing conditions vary between assessment methods, brain biomechanics cannot be fully understood.

View Article and Find Full Text PDF

Study Design: Narrative review.

Objectives: To discuss how electrophysiology may contribute to future clinical trials in spinal cord injury (SCI) in terms of: (1) improvement of SCI diagnosis, patient stratification and determination of exclusion criteria; (2) the assessment of adverse events; and (3) detection of therapeutic effects following an intervention.

Methods: An international expert panel for electrophysiological measures in SCI searched and discussed the literature focused on the topic.

View Article and Find Full Text PDF

Background: Cognitive impairment is a clinically important feature of schizophrenia. Polygenic risk score (PRS) methods have demonstrated genetic overlap between schizophrenia, bipolar disorder (BD), major depressive disorder (MDD), educational attainment (EA), and IQ, but very few studies have examined associations between these PRS and cognitive phenotypes within schizophrenia cases.

Methods: We combined genetic and cognitive data in 3034 schizophrenia cases from 11 samples using the general intelligence factor g as the primary measure of cognition.

View Article and Find Full Text PDF

The cutaneus trunci muscle (CTM) reflex produces a skin "shrug" in response to pinch on a rat's back through a three-part neural circuit: ) A-fiber and C-fiber afferents in segmental dorsal cutaneous nerves (DCNs) from lumbar to cervical levels, ) ascending propriospinal interneurons, and ) the CTM motoneuron pool located at the cervicothoracic junction. We recorded neurograms from a CTM nerve branch in response to electrical stimulation. The pulse trains were delivered at multiple DCNs (T-L), on both sides of the midline, at two stimulus strengths (0.

View Article and Find Full Text PDF

We studied resting-state oscillatory connectivity using magnetoencephalography in healthy young humans (N = 183) genotyped for APOE-ɛ4, the greatest genetic risk for Alzheimer's disease (AD). Connectivity across frequencies, but most prevalent in alpha/beta, was increased in APOE-ɛ4 in a set of mostly right-hemisphere connections, including lateral parietal and precuneus regions of the Default Mode Network. Similar regions also demonstrated hyperactivity, but only in gamma (40-160 Hz).

View Article and Find Full Text PDF

Genome-wide association studies (GWAS) show that many common alleles confer risk for developing Alzheimer's disease (AD). These risk loci may contribute to MRI alterations in young individuals, preceding the clinical manifestations of AD. Prior evidence identifies vascular dysregulation as the earliest marker of disease progression.

View Article and Find Full Text PDF

Study Design: Randomized dual center controlled clinical trial.

Objective: To determine and compare the cardiorespiratory impact of 3 months of aquatic and robotic therapy for individuals with chronic motor incomplete spinal cord injury (CMISCI).

Settings: Two rehabilitation specialty hospitals.

View Article and Find Full Text PDF

Genome-wide association studies have linked common variation in ZNF804A with an increased risk of schizophrenia. However, little is known about the biology of ZNF804A and its role in schizophrenia. Here, we investigate the function of ZNF804A using a variety of complementary molecular techniques.

View Article and Find Full Text PDF

Cytochrome (CYP) P450 enzymes have a primary role in antidepressant metabolism and variants in these polymorphic genes are targets for pharmacogenetic investigation. This is the first meta-analysis to investigate how CYP2C19 polymorphisms predict citalopram/escitalopram efficacy and side effects. CYP2C19 metabolic phenotypes comprise poor metabolizers (PM), intermediate and intermediate+ metabolizers (IM; IM+), extensive and extensive+ metabolizers (EM [wild type]; EM+) and ultra-rapid metabolizers (UM) defined by the two most common CYP2C19 functional polymorphisms (rs4244285 and rs12248560) in Caucasians.

View Article and Find Full Text PDF