Thesis (M.S.O.T.) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / PURPOSE: Past research has shown discrepancy between parent and child report of health-related outcomes, leading to questions regarding the use of parents as proxy reporters for their children. It is not known whether similar discrepancies exist between child and parent views of the child’s participation following spinal cord injury. It is also unclear how perception of participation in youth after spinal cord injury compares to self-perception of participation for youth without disabilities. The current study investigated these questions. PROCEDURE: A secondary analysis was completed on data collected from children and youth with a spinal cord injury ages 8-21 years (n=381) and their parents using the Shriner’s Participation Scale. The young person’s self-perception ratings of participation were compared to his/her parent’s perception of their participation, and patterns of self-perception of participation among peers without disabilities . ICC’s were conducted to determine levels of consistency among parent-child dyad responses. Responses from a sample of children and youth without disabilities (n=2005) were compared by t-test to those of the youth with a spinal cord injury determine whether there were differences in how often each group reported they are unable to participate in certain activities. SUMMARY OF FINDINGS: Overall low levels of agreement were found between parent and child perceptions of the child’s participation. The highest agreement (average ICC) between parent and child was found in the 14-17 year old age group. There was a significant difference in self-perception of ability to participate in certain activities between the youth with spinal cord injury and their peers without disabilities. / 2031-01-01

The lamprey is a basal vertebrate that achieves spontaneous functional recovery after complete spinal cord transection over a stereotypical period of 12 weeks. Despite anatomical, physiological, and behavioral data on spinal cord regeneration in lamprey, the molecular mechanisms underlying this capacity are largely unknown. In this study, next generation RNA-sequencing (RNA-Seq) of the brain and injury site within the spinal cord was used to determine and compare transcriptional profiles of uninjured and recovered lampreys at 12 weeks after spinal cord injury (SCI), when normal swimming behavior is achieved. The objective of this study was to determine if recovered animals had a significantly different transcriptional program than uninjured animals. Significant differences in gene expression were observed, with 1468 and 1033 differentially expressed genes in the spinal cord and brain respectively. Leveraging functional data for mammalian homologs of differentially expressed genes, several conserved transcription factors and molecular pathways in both uninjured and injured animals were identified. Gene expression patterns associated with functional recovery in lampreys may be useful in guiding studies aimed at modulating mammalian responses to spinal cord injury, and promoting functional recovery in species with less spontaneous regenerative potential. / 2019-07-11T00:00:00Z

Class of 2012 Abstract / Specific Aims: The goal of this project was to evaluate the use of a preparation of the brainstem and spinal cord of neonatal rats that has been widely used for observing and quantifying central nervous activity, as well as the response to pharmacological manipulation. To achieve this, we specifically aimed to remove the intact brainstem and spinal cord of newborn rats, and develop a preparation that would maintain physiological function and allow for recording of electrical activity. Methods: Multiple dissections were performed on neonatal rats. Conditions during the dissections were controlled to maintain physiological function. Once removed, the intact brainstem and spinal cord was placed in a preparation that allowed for manipulation and access to nerve rootlets. Finally, glass suction electrodes were used to record electrical activity directly from the nerve rootlets. Once recorded, the data were stored on a hard drive for further analysis. Main Results: We were successful in isolating the intact brainstem and spinal cord in neonatal rats while maintaining physiological conditions and nervous activity. The preparation allowed for easy access to nerve roots as well as customization for different experiments. We were also successful in recording nerve activity in the preparation and collection of data for use in future experiments Conclusions: We conclude that the brainstem spinal cord preparation described in this study is a valuable tool that allows for recording and analysis of nerve activity, and specifically for measurement of respiratory motor output. This is a preparation that can be used in a variety of experiments that attempt to observe or quantify the activity of central nerve cells and allows for pharmacological interventions that could be applied in various experiments.

Functional electrical stimulation (FES) techniques may be used to restore motor function lost or impaired through spinal cord injury. In order to use these techniques to restore complex tasks such as walking, it is necessary to provide sensory feedback to regulate the output of the FES controller. It has been suggested that multi-microelectrode probes (microprobes) implanted into the peripheral nervous system can be used to detect signals originating from the body's own sensors. These signals could be decoded and used to regulate the output of the FES controller. Prior to the present work, however, microprobes had primary been used to study neural activity in the brain, not peripheral nerves. In the present work, locust peripheral nerve has been used as an animal model for experimental and computer modelling work. The experimental work was directed at discerning the detail of information that can be obtained using microprobes to record from peripheral nerves (ie, the selectivity of the probes). In the computer modelling work, the effects of filtering the recorded signal were studied using an electrical circuit simulator programme (SPICE). Finite element analysis software (ANSYS) was used to model the electrical potential distribution in the nerve trunk, and to determine the effects of the probe substrate on the recorded signal. The results of the experimental work indicated that it may be possible to achieve higher selectivity in recording with microprobes than predicted by some models. It is concluded that future models need to represent the situation in greater detail in order to make more realistic predictions regarding the practical work. This will require further data on the electrical properties of the structures modelled within the nerve trunk. The SPICE modelling work successfully predicted the shape of the neural signals that would be recorded in the practical work. The partial differentiating effect of high pass filtering neural signals was also demonstrated. The results of the finite element modelling work demonstrated that the probe substrate would be expected to amplify signals from fibres directly in front of it, and attenuate signals from fibres behind it. This was shown to be significant for probe substrates with dimensions much smaller than the longitudinal spread of the action potential along the fibre. It was also found that these effects can be influenced by the position of the microprobe substrate relative to other structures within the nerve trunk; not just relative to the fibre. The significance of these results as they relate to mammalian nerve is discussed. Improved experimentation techniques and models are outlined, based on the results of this work. These include the requirement for improved facilities to determine the limits of selectivity in recording from peripheral nerves, and also the inclusion of inhomogeneities in models of the nerve trunk to make more realistic predictions regarding practical work. Finally, the development of active probes is discussed, including requirements for particularly novel circuitry, and the integration of many devices into a system to control FES.

Doctorat en sciences médicales / info:eu-repo/semantics/nonPublished

No description available.

No abstract available / Dissertation (MArch (Prof))--University of Pretoria, 2007. / Architecture / unrestricted

The Vascular system of the human spinal cord at birth has been investigated, and a report is submitted on the detailed pattern of the arterial and arteriolar vessels in 27 cadavers. In 21 instances, the anterior median spinal arterial trunk and in 9 instances the postero-lateral spinal arterial trunks have been recorded. Selection of cadavers has been on the basis of the absence of obvious congenital deformity or disease of the spine and spinal cord. Particular attention has been paid to the feeder arteries which contribute to the main longitudinal channels, both anteriorly and posteriorly. The number of feeder vessels, their ;.., sources of origin .and their approximate size~ have been determined. In 21 specimens the anterior vessels have been recorded and charted in detail. (Plates I - VII). In 9 specimens the posterior vessels have been recorded and the detailed charts of 3 of the latter are presented. (Plate X, p.46). Material and Methods Newborn cadavers, obtained on average 3-5 days after death from various causes such as prematurity, cerebral trauma, pneumonia and pulmonary hyaline membrane have been used. In each case the body was warmed to room temperature, before the introduction into the right femoral artery of a plastic tubular cannula of appropriate gauge. Dilute Ammonia, 2-3 ml., was introduced to promote the flow of the injection material and the specimens were injected with latex under pressures which varied from 5 lbs per square inch to 20 lbs per square inch. The manometric readings of intra-arterial pressure were between 300 mms. Hg and 1200 mms. Hg, and the optimal pressure of delivery was 15 lbs per square inch. Both the arterial and the venous sides of the circulation were well-filled by the injection material, which in all instances was administered via the femoral artery. Rupture of vessel walls with leakage of injection material was not excessive. The number of cadavers rejected on account of inadequate filling or excessive leakage was less than 10 out of approximately 50 cadavers. The injection material consisted of a prevulcanised latex, "Revultex", coloured red with an appropriate dye, and stained through fine muslin before use to ensure freedom from solid particles which could cause obstruction of vessels of fine calibre. The injection material was allowed to penetrate the vascular tree for periods varying from 5 to 15 minutes and the cadaver was then embalmed, injecting the body cavities and infiltrating the limbs as far as possible with a standard embalming fluid consisting of: White Industrial Spirits, 45%; Glycerine, 35%; Formaldethyde, 15%; Thymol, q.s. The cadaver was preserved in a 50% solution of the embalming fluid, and dissections were commenced not less than 14 - 21 days after preparation. Use was made in all instances of the binocular surgical microscope, and magnifications of 10 or of 16 were found to be optimal. Photographic reproductions were made in colour, and the dissected specimens have been preserved. The findings in respect of the anterior arterial system of supply of the cord have been consistent with those of a number of workers, in particular Woollam and Millen (1958) of Cambridge. Additional findings have been reported in respect of the smaller arteries (arteries of the 4. 4th order) including the perforating arteries of the median sulcus. The value of a computerised "average" for the vascular pattern of the cord is disputed. In the opinion of the author, it is likely to be misleading to the clinician and to the surgeon. Reliance upon an average picture in an individual case is liable to be harmful; in the present series of 21 specimens, the average picture as offered by Suh and Alexander (1939) was, in some respects only, applicable to 1 case. The presence of arterio-arterial anastomoses as a common feature in the spine is reported, and the possible significance discussed. Reference is made to a "critical narrow zone" which the author has determined by the radiological examination of 50 vertebral columns in people of all ages. When the region of the "narrow critical zone" is related to the regional blood supply of the spinal cord, then a significant factor in the post-operative development of paraplegia in scoliosis cases has been found to emerge. Vascular factors have been sought in the etiology of idiopathic scoliosis, but not found.

Modulation of synaptic transmission in the spinal cord dorsal horn plays an important role in development and maintenance of pathological pain states. The indisputable part of this modulation is conducted via activity of the transient receptor potential cation channel subfamily V member 1 (TRPV1) and the cannabinoid receptor 1 (CB1), expressed on presynaptic endings of primary afferents in the superficial spinal cord dorsal horn. Under physiological conditions, activation of TRPV1 receptors is pronociceptive while CB1 receptor activation leads to attenuation of nociceptive signalling. However, both receptors share also one endogenous agonist anandamide (AEA) that may be produced from N-arachidonoyl phosphatidylethanolamine (20:4-NAPE). Main objective of this thesis focuses on the effect of 20:4-NAPE on nociceptive synaptic transmission in spinal cord slices under naïve and inflammatory conditions and consequent on the possible interaction of TRPV1 and CB1 receptors. First, 20:4-NAPE application induced significant release of anandamide from spinal cord slices under in vitro conditions. Next, patch- clamp recordings of excitatory postsynaptic currents (mEPSC and sEPSC) from superficial dorsal horn (DH) neurons in acute spinal cord slices were used. 20:4-NAPE application under the physiological...

Neurotrauma is a general term describing injury to the central nervous system (CNS); which comprises of the brain and spinal cord. The damage resulting from neurotrauma includes primary injury, which occurs from different sources such as compressed air hitting the brain (bTBI) or an object/bone contusing the spinal cord, resulting in a spinal cord injury (SCI). These various means of primary brain and spinal cord injury are further complicated by the many possible combinations of severity levels and frequencies. However, primary injuries are regarded in many cases as unavoidable with the immediate nerve damage being largely irreversible. Despite all this, primary injuries of the CNS are related by common biochemical pathways in secondary injury. Secondary injury is the cause of declining outcomes after neurotrauma and poor recovery. Secondary injury begins immediately after primary injury and can continue to trigger death of neurons for years later. Given this contribution to poor recovery and its slow progression, secondary injury provides an excellent window of opportunity for therapeutic intervention. A major factor and key link in secondary injury and its perpetuation is reactive aldehyde formation, such as acrolein, from lipid peroxidation. The common formation of acrolein in neurotrauma is attributed to the unique structure of the CNS: with neurons containing a high lipid content from myelin and heavy metabolic activity they are vulnerable to acrolein formation. Thus, acrolein in secondary injury is a point of pathogenic convergence between the various forms of neurotrauma, and may play a role as well in the development of neurotrauma linked disorders and related neurodegeneration. The overall goal of this thesis is to therefore develop better strategies for acrolein removal. We explore here endogenous clearance strategies and targeted drug delivery in SCI, investigate detailed cellular structure changes in bTBI, and acrolein formation and removal in Parkinson’s disease. These findings of pathology, and effectiveness of new or existing acrolein removal strategies, will allow us to better employ treatments in future studies.