Thesis (M.S.)--University of Michigan, 1984.

Thesis (M.S.)--University of Michigan, 1984.

La posture, composante statique du contrôle moteur permettant une position érigée du corps, repose sur une décharge tonique des motoneurones innervant nos muscles antigravitaires. La décharge prend la forme de « potentiel de plateau » au niveau de motoneurones matures chez de nombreux vertébrés. Pour déterminer une éventuelle concordance entre l'émergence des propriétés de plateau et le développement postural, notre travail a eu pour but d'étudier la maturation et la nature ionique des potentiels de plateau des motoneurones innervant le muscle triceps surae (extenseur de la cheville) chez le rat nouveau-né.La réalisation de ces travaux de thèse nous a permis de dégager un mécanisme fondamental dans la genèse des propriétés de plateau des motoneurones lombaires. Ce mécanisme dont le fondement repose sur l'activation d'un « ménage à trois » jouerait un rôle majeur dans le développement moteur chez le rat. Dans la mesure où les potentiels de plateau des motoneurones sont fortement perturbés à la suite d'une lésion médullaire, cette avancée scientifique permettra éventuellement de mieux comprendre l'origine de certains déficits sensori-moteurs (spasticité, hyperalgésie...) et le développement de nouvelles stratégies thérapeutiques. / Posture allowing an erect posture of the body relies on spiking activity of motoneurons innervating antigravitary muscle. Discharge could take the form of plateau potential on mature motoneurons of numerous vertebrates. To determine a possible concordance between the emergence of plateau potential and postural control development, we studied the maturation and ionic nature of plateau potential of motoneurons innervating triceps surae muscle of neonatal rat.The conclusion of our work allows us to propose a fundamental mechanism in the genesis of plateau potential on lumbar motoneurons. This mechanism based on a "ménage a trois" seems to play an important role in the neonatal motor development. This scientific advance could eventually lead to a better understanding of the origin of some sensori-motor impairments (spasticity, hyperalgesia...) and development of therapeutic strategies.

This study aims to explore, and to a certain extent to clarify, what it means psychologically to experience Traumatic spinal cord injury (TSCI) in a South African spinal unit. The target time chosen for analysis is the acute medical period. The study presents a review of the literature on psychological adjustment to TSCI and then proceeds to introduce and extensively articulate the hermeneutic approach and methodology. Subsequently, an interpretive research strategy is presented for the purpose of studying the acute phase of TSCI. The data for the study was obtained by means of three dialogical interviews which were tape recorded, transcribed and analyzed with~n a cyclical framework consisting of three interdependent levels. The interpretive procedure is modeled upon the 'reading guide' developed by Brown, Tappan, Gilligan, Miller and Argyris (1989). The analysis follows a course from the individual psychological descriptions of the experience to the generation of a general, nomothetic narrative account of the acute phase. The findings are then discussed in relation to the existing literature and evaluated on the basis of the goals of the study. The study highlights the value of some of the 'stage' ways of thinking about SCI adjustment, while simultaneously stressing the need for placing adjustment within a more personalized, and individually meaningful context. Significant differences between the psycho-physical experiences of patients in the categories of complete and -incomplete SCI were found, which suggests that a sharper distinction be made in the literature between these two groups, in order to account for the marked variations in their experiences.-- The study also contains a number of shortcomings, such as a lack of understanding about certain historical and contextual factors which may have mediated the experiences of the trauma for the individuals concerned. These shortcomings and some suggestions fro their resolution are then discussed. The study concludes with an evaluation of the research strategy and methodology and also offers some suggestions for future research.

This thesis assessed the suitability of unilateral, electrolytic lesions as a model of spinal cord damage and repair in the adult rat. This type of lesion resulted acutely in localized damage in the upper motor neuron at the L2-L3 level of the spinal cord. Minimal acute damage to ascending sensory pathways was indicated by preserved somatosensory evoked potentials elicited by stimulation of the tibial nerve. Immediately after lesion generation one of several substrates was injected into the lesion cavity. These substrates were saline buffer, liquid collagen solution, foetal spinal cord cells from 14 day old rat embryos, and a mixture of collagen and E 14 foetal spinal cord cells. The 4 groups were compared for functional recovery over 3 months using the inclined plane test and a Tarlov movement scale. After sacrifice, the tibialis anterior muscles were dissected and weighed to assess atrophy due to lower motor neuron injury. After removing and embedding the spinal cords in paraffin, transverse and longitudinal sections were taken for cytoarchitectural investigation. Cresyl violet was used to indicate Nissl substance, Luxol fast blue stained for myelin and anti - glial fibrillary acidic protein (GFAP) antibody revealed the expression of GFAP in the cord sections. Chronic electrolytic lesions were characterized by the highly variable degree of cavitation, demyelination and macrophage infiltration that was present. There was no significant performance deficit on the inclined plane test in any of the lesioned groups when compared to unoperated animals. The tibialis muscles from all groups were of normal weight, indicating that the lower motor neurons were not significantly damaged by the lesions used. There was, however, a marked decrease in the number of GFAP reactive astrocytes in the lesioned animals when compared to unlesioned controls (P < 0.01, Wilcoxon test). Moreover, this reduction of GFAP - like immunoreactivity was not prevented by implants of foetal neurons, collagen or foetal neurons suspended in collagen. Possible explanations for the reduced GFAP - like immunoreactivity seen in all electrolytically lesioned cords are discussed. / Medicine, Faculty of / Cellular and Physiological Sciences, Department of / Graduate

No description available.

No description available.

Thesis advisor: Mary E. Duffy / Ten people with tetraplegic spinal cord injuries participated in a nurse-coached exercise intervention/single subject design study over a period of six months. Four pieces of exercise equipment were used: the RT300S Functional Electrical Stimulation Bike, the VIta Glide, the NuStep TRS 4000, and the Easy Stand Evolv Glider. Measurement of variables of the Manual Muscle Test (MMT), Catz-Itzkovich Spinal Cord Independence Measures (CI-SCIM), and Moorong Self-Efficacy Scale (MSES) were collected at baseline, at three months into the exercise intervention, and at six months (at the conclusion of the intervention). Results were determined by visual analysis of graphs, in keeping with single subject design methods, and statistical analysis of combined data. Of those muscles that demonstrated some strength at baseline, 75% experienced increased strength at three and/or six months into the intervention. Of those muscles that demonstrated no strength at baseline and that were adjacent to muscles that demonstrated some strength at baseline, 66% were found to have increased strength at three and/or six months. Nine of ten participants experienced upward trends in CI-SCIM scores overall (p<.0001). The results of the subscales of Self-Care (p<.0001) and Mobility (p<.0001) indicated statistically significant changes over time. The subscale Respiratory and Sphincter Management was not statistically significant (p>.05). Visual analysis of graphs demonstrated that each of ten participants experienced strong improvements in self-efficacy scores from baseline to three months and from three months to six months into the intervention. R-ANOVA (p<.0001) confirmed statistical significance across ten participants. The Sheehy Spinal Cord Injury Functional Improvement Via Exercise (SCI-FIVE) Model was constructed prior to the study and validated throughout the course of the study. The results of the study validated all components of the Model and demonstrated increased muscle strength, increased self-efficacy, and improved quality of life for the ten study participants who participated in a nurse-coached exercise intervention for people with tetraplegic spinal cord injuries. / Thesis (PhD) — Boston College, 2010. / Submitted to: Boston College. Connell School of Nursing. / Discipline: Nursing.

Chondroitin sulfate proteoglycans (CSPGs) are one major class of axon growth inhibitors that are upregulated and accumulated around the lesion site after spinal cord injury (SCI), and result in regenerative failure. To overcome CSPG-mediated inhibition, digestion of CSPGs with chondroitinase ABC (chABC) has been explored and it has shown promising results. chABC digests glycosaminoglycan chains on CSPGs and can thereby enhance axonal regeneration and promote functional recovery when delivered at the site of injury. However, chABC has a crucial limitation; it is thermally unstable and loses its enzymatic activity rapidly at 37 ºC. Therefore, it necessitates the use of repeated injections or local infusions with a pump for days to weeks to provide fresh chABC to retain its enzymatic activity. Maintaining these infusion systems is invasive and clinically problematic. In this dissertation, three studies are reported that demonstrate our strategy to overcome current limitations of using chABC and develop a delivery system for facilitating chABC treatment after SCI: First, we enhanced the thermostability of chABC by adding trehalose, a protein stabilizer, and developed a system for its sustained local delivery in vivo. Enzymatic activity was assayed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and dimethylmethylene blue (DMMB), and conformational change of the enzyme was measured via circular dichroism (CD) with and without trehalose. When stabilized with trehalose, chABC remained enzymatically active at 37 ºC for up to 4 weeks in vitro. We developed a lipid microtube-agarose hydrogel delivery system for a sustained release and showed that chABC released from the delivery system is still functionally active and slowly released over 2 weeks in vitro. Second, the hydrogel-microtube system was used to locally deliver chABC over two weeks at the lesion site following a dorsal over hemisection injury at T10. The scaffold consisting of hydrogel and chABC loaded lipid microtubes was implanted at the top of the lesion site immediately following injury. To determine effectiveness of topical delivery of thermostabilized chABC, animal groups treated with single injection or gel scaffold implantation of chABC and penicillinase (P'ase) were included as controls. Two weeks after surgery, the functionality of released chABC and the cellular responses were examined by immunohistological analysis with 3B3, CS-56, GFAP and Wisteria floribunda agglutinin (WFA). The results demonstrated that thermostabilized chABC was successfully delivered slowly and locally without the need for an indwelling catheter by using the hydrogel-microtube delivery system in vivo. The results demonstrated that released chABC from the gel scaffold effectively digested CSPGs, and therefore, there were significant differences in CSPG digestion at the lesion site between groups treated with chABC loaded microtube-hydrogel scaffolds and controls. Third, a long term in vivo study (45 days) was conducted to examine axonal sprouting/regeneration and functional recovery with both a single treatment each of microtube loaded chABC or Neurotrophin-3 (NT-3), and a combination of them by using the hydrogel-microtube delivery system. Over the long term study period, the treated animals showed significant improvement in locomotor function and more sprouting of cholera toxin B subunit (CTB)-positive ascending dorsal column fibers and 5-HT serotonergic fibers around the lesion site. We demonstrated that this significant improvement of chABC thermostability facilitates the development of a minimally invasive method for sustained, local delivery of chABC that is potentially a useful and effective approach for treating SCI. In addition to that, we demonstrated that combinatorial therapy with chABC and neurotrophic factors could provide a synergistic effect on axonal regrowth and functional recovery after SCI.

published_or_final_version / Psychiatry / Master / Master of Philosophy