Impact of the COVID-19 Pandemic on a Clinical Trial: A Quantitative Report on Study Engagement and Strategies.

Introduction: The COVID-19 pandemic impacted clinical research worldwide potentially altering research findings. The study purpose was to measure the effect of the pandemic on recruitment, retention, assessment, and intervention completion rates.

Methods: Enrollment and participation data from a clinical trial evaluating efficacy of a physical therapy intervention for high-risk preterm infants were compared across 3 pandemic periods (February 2019 through November 2021).

Effect of a NICU to Home Physical Therapy Intervention on White Matter Trajectories, Motor Skills, and Problem-Solving Skills of Infants Born Very Preterm: A Case Series.

Infants born very preterm (VPT; ≤29 weeks of gestation) are at high risk of developmental disabilities and abnormalities in neural white matter characteristics. Early physical therapy interventions such as Supporting Play Exploration and Early Development Intervention (SPEEDI2) are associated with improvements in developmental outcomes. Six VPT infants were enrolled in a randomised clinical trial of SPEEDI2 during the transition from the neonatal intensive care unit to home over four time points.

Longitudinal Changes in the Sensorimotor Pathways of Very Preterm Infants During the First Year of Life With and Without Intervention: A Pilot Study.

: Evaluate longitudinal changes in brain microstructure and volumes in very preterm infants during the first year of life with and without intervention.: Descriptive pilot study.: Five preterm infants in a three-arm clinical trial, one SPEEDI Early, two SPEEDI Late, and two usual care.

A Motor Learning Paradigm Combining Technology and Associative Learning to Assess Prone Motor Learning in Infants.

Background: Associative learning is the ability to discover a relationship between two or more events. We combined principles of learning and technology to develop a paradigm to assess associative learning in prone.

Purpose: The purpose of this study was to determine whether 3- to 6-month-old infants can demonstrate: (1) short-term learning of an association between their upper body movements in prone and activation of a toy, and (2) retention of the association learned on day 1, 24 hours later.

The importance of saccular function to motor development in children with hearing impairments.

Children with hearing deficits frequently have delayed motor development. The purpose of this study was to evaluate saccular function in children with hearing impairments using the Vestibular Evoked Myogenic Potential (VEMP). The impact of the saccular hypofunction on the timely maturation of normal balance strategies was examined using the Movement Assessment Battery for Children (Movement ABC).

Polyneuronal innervation of single muscle fibers in cat eye muscle: inferior oblique.

Single muscle fibers with multiple axonal endplates (multiply innervated fibers) are normally present in adult extraocular muscles (EOMs), while most other mammalian skeletal muscles contain fibers with a single myoneural junction. Recent findings by others led us to investigate for the presence of polyneuronal innervation (innervation of a single muscle fiber by >1 motoneuron) in the inferior oblique (IO) muscle of pentobarbital anesthetized cats. The IO muscle nerve branches, as they coursed through the orbit, were further divided for independent or simultaneous electrical stimulation with bipolar electrodes.

Anatomic and physiological characteristics of the ferret lateral rectus muscle and abducens nucleus.

The ferret has become a popular model for physiological and neurodevelopmental research in the visual system. We believed it important, therefore, to study extraocular whole muscle as well as single motor unit physiology in the ferret. Using extracellular stimulation, 62 individual motor units in the ferret abducens nucleus were evaluated for their contractile characteristics.

Effects of artificial rearing on contractile properties of genioglossus muscle in Sprague-Dawley rat.

Mammals suckle from a nipple during the early neonatal period to obtain nourishment. The genioglossus muscle helps position and move the tongue for efficient suckling. The purpose of this study was to examine the contractile properties and myosin heavy chain (MHC) phenotype of the genioglossus following an early period of artificial rearing, which reduced nutritive suckling.

Contractile properties and myosin heavy chain composition of rat tongue retrusor musculature show changes in early adulthood after 19 days of artificial rearing.

Previously, we showed that artificial rearing using the "pup in a cup" model results in decreased tongue activity and caused some minor alterations in the tongue retrusor musculature. However, the artificial rearing time frame previously chosen was brief (11 days). The purpose of the present investigation was to extend the artificial rearing period from postnatal days 3 to 21 (P21) to determine whether significant alterations occur as a result of this reduced tongue use.

Neonatal bilabyrinthectomy leads to changes in skeletal muscle fiber form and function.

Children with hypoactive semicircular canals commonly have delayed motor development. We studied ferrets whose vestibular labyrinths were removed at postnatal day 10 (P10) to evaluate 1) development of motor behavior, 2) soleus contractile characteristics, 3) muscle fiber diameter, and 4) the expression of myosin heavy chain (MHC) isoforms. At P30 labyrinthectomized (LAB) ferrets exhibited a significant delay in motor development.

Lateral rectus muscle changes after bilateral neonatal labyrinthectomy in the ferret.

The vestibular system is essential to the coordination of eye movements during head movements. Exercise, such as the eye movements mediated by the vestibular system, is a major factor in the development of muscle fiber types and the strength of muscle. In this study, the contents of the inner ear were removed (labyrinthectomy) from (LAB) ferrets at postnatal day 10 (P10) and raised with control (SHAM) animals.

Myosin heavy chain and fibre diameter of extrinsic tongue muscles in rhesus monkey.

Objective: The purpose of this investigation was to identify the myosin heavy chain (MHC) phenotype and fibre diameters of hypoglossal innervated extrinsic tongue muscles in rhesus monkey.

Methods: Genioglossus, styloglossus and hyoglossus muscle samples obtained from three female rhesus monkeys were analysed for MHC isoforms via gel electrophoresis and stained with MHC antibodies to measure least mean diameters.

Results: MHC phenotypes were consistent for all three muscles.

Phenotype and contractile properties of mammalian tongue muscles innervated by the hypoglossal nerve.

The XIIth cranial nerve plays a role in chewing, respiration, suckling, swallowing, and speech [Lowe, A.A., 1981.

Stimulation-evoked eye movements with and without the lateral rectus muscle pulley.

Recent studies have suggested that extraocular muscle (EOM) pulleys, composed of collagen, elastin, and smooth muscle, are among the tissues surrounding the eye. High-resolution magnetic-resonance imaging appears to indicate that the pulleys serve to both constrain and alter the pulling paths of the EOMs. The active pulley hypothesis suggests that the orbital layer of the EOMs inserts on the pulley and serves to control it.

Effect of artificial rearing on the contractile properties and myosin heavy chain isoforms of developing rat tongue musculature.

This study's purpose was to examine the influence of an altered activity level, via artificial rearing, on the contractile properties, myosin heavy chain phenotypes (MHC), and muscle fiber sizes of the developing rat tongue retractor musculature. Artificially reared rat pups were fed through a gastric cannula, eliminating nutritive suckling from postnatal day 4 to postnatal day 14. Rat pups were observed immediately following artificial rearing (postnatal day 14) and after a 1-mo resumption of function (postnatal day 42).

Extraocular motor unit and whole-muscle contractile properties in the squirrel monkey. Summation of forces and fiber morphology.

In order to understand the neural control of movement, many investigations have examined the contractile properties of single motor units contracting in isolation, and a great majority of those studies have been done in the cat. Fewer studies, again primarily in the cat, have examined motor units acting in concert in both hind-limb and extraocular muscles. It has been shown, in general, that when individual motor unit forces are added together they do not always add linearly, which makes our understanding of motor control somewhat more complicated.

Short-term effects of botulinum toxin on the lateral rectus muscle of the cat.

Botulinum toxin type A (BTX) is often used as an alternative to surgery for the treatment of strabismus and many other motor or cosmetic problems. Although numerous studies established BTX as a powerful transmission-blocking agent at the neuromuscular junction, no evaluation of extraocular muscle (EOM) contractile properties after administration of BTX exists. Some anatomical studies on EOM fiber types suggested a long-term preferential effect of BTX on orbital layer, singly innervated muscle fibers.