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American Journal of Medical Genetics.... Sep 2020To report ophthalmic findings of patients without colobomas, and with a clinical and molecular diagnosis of CHARGE Syndrome. Retrospective study of ophthalmic findings...
To report ophthalmic findings of patients without colobomas, and with a clinical and molecular diagnosis of CHARGE Syndrome. Retrospective study of ophthalmic findings in 67 CHARGE patients-clinically confirmed diagnosis with positive CHD7 mutation-seen in the Ophthalmology department of Cincinnati Children's Hospital Medical Center between January 1, 2008 through September 25, 2018. Criteria for inclusion in this study was absence of any form of a coloboma in either eye. In our cohort, all patients had a positive CHD7 mutation, in addition to a clinical diagnosis. 19.4% (13/67) of CHARGE patients did not have a coloboma in either eye. 69.2% (9/13) had strabismus, 76.9% (10/13) had a refractive error that warranted refractive correction, 23.1% (3/13) had amblyopia, 38.5% (5/13) had nasolacrimal duct obstruction, 30.8% (4/13) had dry eye syndrome and exposure keratopathy, 15.4% (2/13) had ptosis, 15.4% (2/13) had blepharitis, 15.4% (2/13) had Cortical Visual Impairment, 7.7% (1/13) of patients had optic nerve drusen, 7.7% (1/13) had Marcus Gunn Jaw Winking, and 7.7% (1/13) with an eyelid nevus. There are numerous ophthalmic findings in individuals with CHARGE Syndrome without colobomas. No study to date has evaluated the ophthalmic findings in CHD7 positive CHARGE patients without colobomas. These findings need to be assessed and treated to ensure optimal vision in the CHARGE patient population. Absence of coloboma does not rule out a diagnosis of CHARGE syndrome, and if there is a clinical suspicion, clinical confirmation then genetic testing would be warranted.
Topics: Adolescent; Blepharoptosis; CHARGE Syndrome; Child; Child, Preschool; Coloboma; DNA Helicases; DNA-Binding Proteins; Female; Heart Defects, Congenital; Humans; Infant; Jaw Abnormalities; Lacrimal Duct Obstruction; Male; Mutation; Nasolacrimal Duct; Nervous System Diseases; Optic Nerve; Reflex, Abnormal
PubMed: 32914532
DOI: 10.1002/ajmg.c.31840 -
Journal of Neurophysiology Mar 2015Hyperreflexia and spasticity are chronic complications in spinal cord injury (SCI), with limited options for safe and effective treatment. A central mechanism in...
Hyperreflexia and spasticity are chronic complications in spinal cord injury (SCI), with limited options for safe and effective treatment. A central mechanism in spasticity is hyperexcitability of the spinal stretch reflex, which presents symptomatically as a velocity-dependent increase in tonic stretch reflexes and exaggerated tendon jerks. In this study we tested the hypothesis that dendritic spine remodeling within motor reflex pathways in the spinal cord contributes to H-reflex dysfunction indicative of spasticity after contusion SCI. Six weeks after SCI in adult Sprague-Dawley rats, we observed changes in dendritic spine morphology on α-motor neurons below the level of injury, including increased density, altered spine shape, and redistribution along dendritic branches. These abnormal spine morphologies accompanied the loss of H-reflex rate-dependent depression (RDD) and increased ratio of H-reflex to M-wave responses (H/M ratio). Above the level of injury, spine density decreased compared with below-injury spine profiles and spine distributions were similar to those for uninjured controls. As expected, there was no H-reflex hyperexcitability above the level of injury in forelimb H-reflex testing. Treatment with NSC23766, a Rac1-specific inhibitor, decreased the presence of abnormal dendritic spine profiles below the level of injury, restored RDD of the H-reflex, and decreased H/M ratios in SCI animals. These findings provide evidence for a novel mechanistic relationship between abnormal dendritic spine remodeling in the spinal cord motor system and reflex dysfunction in SCI.
Topics: Aminoquinolines; Animals; Dendritic Spines; H-Reflex; Male; Motor Neurons; Pyrimidines; Rats; Rats, Sprague-Dawley; Reflex, Abnormal; Spinal Cord Injuries
PubMed: 25505110
DOI: 10.1152/jn.00566.2014 -
International Archives of Occupational... Feb 2016In the occupational environment, there are a considerable number of stressors that can affect physical performance in job tasks. Whole-body vibration (WBV), which arises... (Review)
Review
INTRODUCTION
In the occupational environment, there are a considerable number of stressors that can affect physical performance in job tasks. Whole-body vibration (WBV), which arises from vehicle transit, is one such stressor that has been demonstrated to alter human function in several ways. This study identifies the known physical changes to human function which result from WBV, to comment on changes which may translate to performance in physically demanding occupational tasks.
METHODS
A systematic review is performed on the literature relating to changes in the neuromuscular, physiological and biomechanical properties of the human body, when exposed to WBV. Selection criteria are constructed to synthesise articles which strictly relate to in-vehicle WBV and physical responses.
RESULTS
In total, 29 articles were identified which satisfied the criteria for inclusion. A range of physical responses produced from WBV are presented; however, little consistency exists in study design and the responses reported.
DISCUSSION
Given the inconsistency in the reported responses, the precise changes to human function remain unknown. However, there is sufficient evidence to warrant the design of studies which investigate occupationally relevant physical performance changes following WBV.
Topics: Heart Rate; Humans; Muscle Fatigue; Muscle, Skeletal; Occupational Exposure; Postural Balance; Reflex, Abnormal; Respiratory Function Tests; Vibration
PubMed: 26012875
DOI: 10.1007/s00420-015-1062-x -
Amino Acids May 2021In this study, we examined neuronal excitability and skeletal muscle physiology and histology in homozygous knockout mice lacking cysteine sulfonic acid decarboxylase...
In this study, we examined neuronal excitability and skeletal muscle physiology and histology in homozygous knockout mice lacking cysteine sulfonic acid decarboxylase (CSAD-KO). Neuronal excitability was measured by intracerebral recording from the prefrontal cortex. Skeletal muscle response was measured through stretch reflex in the ankle muscles. Specifically, we measured the muscle tension, amplitude of electromyogram and velocity of muscle response. Stretch reflex responses were evoked using a specialized stretching device designed for mice. The triceps surae muscle was stretched at various speeds ranging from 18 to 18,000° s. A transducer recorded the muscle resistance at each velocity and the corresponding EMG. We also measured the same parameter in anesthetized mice. We found that at each velocity, the CSAD-KO mice generated more tension and exhibited higher EMG responses. To evaluate if the enhanced response was due to neuronal excitability or changes in the passive properties of muscles, we anesthetize mice to eliminate the central component of the reflex. Under these conditions, CSAD-KO mice still exhibited an enhanced stretch reflex response, indicating ultrastructural alterations in muscle histology. Consistent with this, we found that sarcomeres from CSAD-KO muscles were shorter and thinner when compared to control sarcomeres. Neuronal excitability was further investigated using intracerebral recordings of brain waves from the prefrontal cortex. We found that extracellular field potentials in CSAD-KO mice were characterized by reduced amplitude of low-frequency brain waves (delta, theta, alpha, beta and gamma) and increased in the high low-frequency brain waves (slow and fast ripples). Increased slow and fast ripple rates serve as a biomarker of epileptogenic brain. We have previously shown that taurine interacts with GABA receptors and induces biochemical changes in the GABAergic system. We suggest that taurine deficiency leads to alterations in the GABAergic system that contribute to the enhanced stretch reflex in CSAD-KO mice through biochemical mechanisms that involve alterations not only at the spinal level but also at the cortical level.
Topics: Animals; Carboxy-Lyases; Electromyography; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Muscle, Skeletal; Neurons; Reflex, Abnormal; Reflex, Stretch; Taurine
PubMed: 33877450
DOI: 10.1007/s00726-021-02977-x -
Medicine and Science in Sports and... Jan 2018Hyperthermia has been shown to affect both central and peripheral nervous systems. However, the consequences of these alterations on the proprioceptive mechanisms...
PURPOSE
Hyperthermia has been shown to affect both central and peripheral nervous systems. However, the consequences of these alterations on the proprioceptive mechanisms underlying human movement control remain unclear. The aim of this study was to investigate the effect of passive hyperthermia on various measures of proprioception and balance, two key components of injury prevention and movement efficiency.
METHODS
After a familiarization session, 14 volunteers (8 males, 6 females) completed two experimental sessions in temperate (CON, 24°C) and hot (HOT, 44°C-50°C) conditions, in a counterbalanced order. Participants were tested for neural function (electrically evoked M-wave and Hoffman reflex, Soleus), active movement discrimination (five positions, 50 trials, dorsiflexion), dynamic balance (Star Excursion Balance Test, three directions), and static balance (single-leg stance).
RESULTS
Both rectal (39.0°C ± 0.3°C vs 36.9°C ± 0.6°C) and mean skin (37.9°C ± 1.0°C vs 32.0°C ± 2.7°C) temperatures were significantly higher in HOT than CON (P < 0.05). Hyperthermia significantly reduced the Hoffman reflex (P < 0.05) but not the M-wave (P > 0.05) amplitudes, increased the mean error for active movement discrimination (0.58°± 0.13° vs 0.50° ± 0.11°, +17%, P < 0.05), decreased the average distance reached in the posteromedial direction during dynamic balance (88.6 ± 7.9 cm vs 90.9 ± 6.1 cm, P < 0.05), and increased the contact area of the foot (126 ± 14 cm vs 122 ± 13 cm, +2.7%, P < 0.05) and the center of pressure excursion (64 ± 14 vs 57 ± 9 cm, +11.1%, P < 0.10) during single-leg stance.
CONCLUSIONS
The current study suggests that hyperthermia impairs the proprioception and balance parameters measured. These observations might be due to heat-induced alterations in efferent and afferent signals to and from the muscle.
Topics: Adult; Biomechanical Phenomena; Female; Fever; Humans; Hyperthermia, Induced; Male; Movement; Postural Balance; Proprioception; Reflex, Abnormal
PubMed: 28863075
DOI: 10.1249/MSS.0000000000001418 -
Clinical Pediatrics Oct 2020
Topics: Arnold-Chiari Malformation; Child; Humans; Magnetic Resonance Imaging; Male; Neurologic Examination; Reflex, Abnormal; Scoliosis
PubMed: 32666819
DOI: 10.1177/0009922820941205 -
Brain : a Journal of Neurology Sep 2023Although rigidity is a cardinal motor sign in patients with Parkinson's disease (PD), the instrumental measurement of this clinical phenomenon is largely lacking, and...
Although rigidity is a cardinal motor sign in patients with Parkinson's disease (PD), the instrumental measurement of this clinical phenomenon is largely lacking, and its pathophysiological underpinning remains still unclear. Further advances in the field would require innovative methodological approaches able to measure parkinsonian rigidity objectively, discriminate the different biomechanical sources of muscle tone (neural or visco-elastic components), and finally clarify the contribution to 'objective rigidity' exerted by neurophysiological responses, which have previously been associated with this clinical sign (i.e. the long-latency stretch-induced reflex). Twenty patients with PD (67.3 ± 6.9 years) and 25 age- and sex-matched controls (66.9 ± 7.4 years) were recruited. Rigidity was measured clinically and through a robotic device. Participants underwent robot-assisted wrist extensions at seven different angular velocities randomly applied, when ON therapy. For each value of angular velocity, several biomechanical (i.e. elastic, viscous and neural components) and neurophysiological measures (i.e. short and long-latency reflex and shortening reaction) were synchronously assessed and correlated with the clinical score of rigidity (i.e. Unified Parkinson's Disease Rating Scale-part III, subitems for the upper limb). The biomechanical investigation allowed us to measure 'objective rigidity' in PD and estimate the neuronal source of this phenomenon. In patients, 'objective rigidity' progressively increased along with the rise of angular velocities during robot-assisted wrist extensions. The neurophysiological examination disclosed increased long-latency reflexes, but not short-latency reflexes nor shortening reaction, in PD compared with control subjects. Long-latency reflexes progressively increased according to angular velocities only in patients with PD. Lastly, specific biomechanical and neurophysiological abnormalities correlated with the clinical score of rigidity. 'Objective rigidity' in PD correlates with velocity-dependent abnormal neuronal activity. The observations overall (i.e. the velocity-dependent feature of biomechanical and neurophysiological measures of objective rigidity) would point to a putative subcortical network responsible for 'objective rigidity' in PD, which requires further investigation.
Topics: Humans; Parkinson Disease; Muscle Rigidity; Reflex, Stretch; Reflex, Abnormal; Electromyography
PubMed: 37018058
DOI: 10.1093/brain/awad114 -
European Spine Journal : Official... May 2017Sinus histiocytosis with massive lymphadenopathy or Rosai-Dorfman disease (RDD) is a rare benign disease of dubious etiology that arises predominantly in lymph nodes... (Review)
Review
OBJECTIVE
Sinus histiocytosis with massive lymphadenopathy or Rosai-Dorfman disease (RDD) is a rare benign disease of dubious etiology that arises predominantly in lymph nodes with generalized fever and malaise. Isolated intraspinal involvement has its unique characteristics. The purpose of this study is to present the largest series of cases in the spinal Rosai-Dorfman disease literature to increase familiarity with its clinicopathologic features, diagnosis, and treatment of RDD from spine.
METHODS
We present the case of a 34-year-old man who presented with paraplegia secondary to an isolated thoracic vertebral lesion. On physical exam, the patient displayed progressive weakness and tendon hyperreflexia of the lower limbs. After a totally section, symptoms of the patient were obviously relieved and the patient remained asymptomatic and no signs of recurrences were observed after follow-up for 5 months. We also retrospectively analyzed 60 cases of patients with spinal RDD published in English since 1969. Clinical date, histopathology, and radiological feature were retrospectively analyzed.
RESULTS
Spinal RDD should no longer be considered rare and it may occupy an increasingly prominent place in the list of differential diagnoses for intraspinal lesions. Only elaborate histopathology was diagnostic for RDD. Most of the patients were surgically treated and marked improvements were observed in their clinical conditions.
CONCLUSIONS
RDD with spinal involvement is uncommon and it is challengeable in making a certain diagnosis. Histopathologic characteristics and immunohistochemical findings are considered as the key points for the diagnosis of this disease. The optimal treatment remains controversial, and more efforts should be focused on the investigation of etiology and adjuvant therapy for relapsing cases or subresected lesions.
Topics: Adult; Diagnosis, Differential; Histiocytosis, Sinus; Humans; Magnetic Resonance Imaging; Male; Paraplegia; Recurrence; Reflex, Abnormal; Retrospective Studies; Spinal Cord Compression; Spinal Diseases; Thoracic Vertebrae
PubMed: 28168342
DOI: 10.1007/s00586-017-4975-0 -
Movement Disorders : Official Journal... May 2017The characterization of prodromal stages in neurodegenerative disorders is becoming increasingly important because of the need for early neuroprotective therapies.... (Review)
Review
The characterization of prodromal stages in neurodegenerative disorders is becoming increasingly important because of the need for early neuroprotective therapies. Research during the past 3 decades in spinocerebellar ataxia type 2 has revealed a large body of evidence suggesting that many disease features precede the manifest cerebellar syndrome, which delineates the prodromal stage of this disorder. This stage is defined by clinical, imaging, and functional criteria, which are supported by early molecular events demonstrated in animal models. Knowledge regarding prodromal spinocerebellar ataxia type 2 provides insight into the mechanisms underlying neurodegeneration from the early stages, which enables the design of promising disease-modifying clinical trials through the identification of the optimum moment to begin the therapies, the appropriate selection of individuals, and the identification of sensitive outcome measures. The management of patients in prodromal spinocerebellar ataxia type 2 may raise ethical dilemmas related to predictive diagnosis and early interventions, which impose new challenges to clinical and therapeutic research. © 2017 International Parkinson and Movement Disorder Society.
Topics: Ataxin-2; Brain; Early Diagnosis; Early Medical Intervention; Ethics, Medical; Evoked Potentials, Auditory, Brain Stem; Evoked Potentials, Somatosensory; Eye Movement Measurements; Genetic Testing; Humans; Muscle Cramp; Neural Conduction; Olfaction Disorders; Polysomnography; Primary Dysautonomias; Prodromal Symptoms; Reflex, Abnormal; Spinocerebellar Ataxias; Transcranial Magnetic Stimulation
PubMed: 28256108
DOI: 10.1002/mds.26969 -
International Journal of Environmental... Mar 2022Background: Primitive reflexes (PRs) are observed as an automatic response to a specific stimulus. They are vivid from intrauterine life to 6 months postnatal. The... (Observational Study)
Observational Study
Background: Primitive reflexes (PRs) are observed as an automatic response to a specific stimulus. They are vivid from intrauterine life to 6 months postnatal. The reactions are inhibited with the growing maturation of the central nervous system (CNS). In some cases, when the natural process of development is incorrect, PRs manifest later. The analysis of differentiation in gait parameters in children with persistent PRs is important for better understanding their specific behaviour and movement. This study’s aim was to investigate the influence of active PRs on the gait parameters of preschool children. Methods: There were 50 children examined, 30 girls and 20 boys. They were 3.5−6 years old. The children had persistent PRs in the trace form. Each child was examined by S. Goddard’s Battery Test. The acquisition of the spatial-temporal gait parameters was performed using a BTS G-SENSOR measurement instrument. Participants walked barefoot, in the most natural way for them, at a self-selected speed on a 5 m walkway, then turned around and went back. They performed this twice. Results: The reflex activity influences gait cycle duration (p = 0.0099), the left step length (p = 0.0002), the left double support phase (p = 0.0024), the right double support phase (p = 0.0258) and the right single phase. Difficulties in recreating the crawling pattern and GRASP reflex influence gait cadence (p < 0.05). The left GRASP reflex corresponds to step length (p < 0.05). The activeness of the symmetrical tonic neck reflex correlates with the right single support (p < 0.05). Conclusion: The presence of PRs affect walking gait in preschool children.
Topics: Child; Child, Preschool; Female; Gait; Humans; Male; Movement; Reflex; Reflex, Abnormal; Walking
PubMed: 35409750
DOI: 10.3390/ijerph19074070