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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
441

The extracellular matrix regulates myoblast migration during wound healing.

Goetsch, Kyle Peter. January 2012 (has links)
Mammalian skeletal muscle can regenerate after injury and this response is primarily mediated by the satellite cell, a muscle stem cell. Following injury, satellite cells are activated to myoblasts, undergo rapid proliferation, migrate towards the injury site, and subsequently differentiate into myotubes in order to facilitate functional muscle repair. Fibrosis, caused by the secretion of structural extracellular matrix (ECM) proteins such as collagen I and fibronectin, by fibroblasts, impairs complete functional repair of the muscle. In this study, the role of the microenvironment during wound conditions was assessed by analysing the effect of specific extracellular matrix and growth factors on myoblast migration. The role of the Rho/ROCK pathway as a possible mechanism in mediating the effects seen was investigated. In order to analyse wound repair in an in vitro setting, we optimised and improved a wound healing model specifically designed for skeletal muscle repair. To this end we also developed a co-culture assay using primary myoblasts and fibroblasts isolated from the same animal. The studies showed that collagen I and fibronectin both increased myoblast migration in a dose-dependent manner. Decorin displayed opposing effects on cellular movement, significantly increasing collagen I-stimulated, but not fibronectin-stimulated, migration of myoblasts. ROCK inhibitor studies revealed a significant increase in migration on uncoated plates following inhibition with Y-27632 compared to untreated control. When cells were cultured on ECM components (Matrigel, collagen I, or fibronectin), the inhibitory effect of Y-27632 on migration was reduced. Analysis of ROCK and vinculin expression, and localization at the leading front, showed that ROCK inhibition resulted in loosely packed focal adhesion complexes (matrix dependent). A reduced adhesion to the ECM could explain the increased migration rates observed upon inhibition with Y-27632. We also investigated the role of TGF-β and decorin during wound repair, as TGF-β is a known pro-fibrotic agent. TGF-β treatment decreased wound closure rates; however, the addition of decorin with TGF-β significantly increased wound closure. The addition of ECM components, Matrigel and collagen I enhanced the effect seen in response to TGF-β and decorin; however, fibronectin negated this effect, with no increase in migration seen compared to the controls. In conclusion, the importance of extracellular matrix components in regulating myoblast migration and therefore skeletal muscle wound repair was demonstrated. We emphasize that, in order to gain a better understanding of skeletal muscle wound repair, the combination of ECM and growth factors released during wounding need to be utilised in assays which mimic the in vivo environment more closely. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
442

The relationship between leg dominance and knee mechanics during the cutting maneuver

Brown, Scott R. 21 July 2012 (has links)
The purpose of this study was to examine the relationship between leg dominance and knee mechanics to provide further information about the etiology of ACL injury. Sixteen healthy females between the ages of 18 and 22 who were NCAA Division I varsity soccer players participated in this study. Subjects were instructed to perform a cutting maneuver; where they sprinted full speed and then performed an evasive maneuver (planting on one leg and pushing off to the other leg in a new direction) at a 45° angle with their dominate leg (DL) and non-dominate leg (NDL). Subjects were required to perform five successful cuts on each side given in a random order. Bilateral kinematic and kinetic data were collected during the cutting trials. After the cutting trials, subjects performed bilateral isometric and isokinetic testing using a Cybex Norm dynamometer at a speed of 60°/sec to evaluate knee muscle strength. During the braking phase the NDL showed greater (P=0.003) power absorption, greater (P=0.01) peak internal rotation angle and greater (P=0.005) peak flexion velocity. During the propulsive phase the DL showed greater (P=0.01) power production, greater (P=0.038) peak internal adductor moment and greater (P=0.02) peak extension velocity. In addition, no differences (P>0.05) in knee extensor and flexor isometric and isokinetic torques between the two limbs were shown. The results of this study show that a difference in knee mechanics during cutting does exist between the DL and NDL. The findings of this study will increase the knowledge base of ACL injury in females and aid in the design of more appropriate neuromuscular, plyometric and strength training protocols for injury prevention. / School of Physical Education, Sport, and Exercise Science
443

Head Trauma Release of Histamine from Dural Mast Cells Alters Blood-Brain Barrier: Attenuation with Zolantidine

Laufer, Susan R. 12 1900 (has links)
This study employed a new model of mild-to-moderate head trauma to specifically identify the role of dural mast cell (MC) histamine in trauma-induced increased permeability in the blood-brain barrier (BBB). A single line was scored partially through the left dorsal parietal skull. Immediately following the trauma, degranulation was seen in 39% of the MCs on the left and in 2% on the right. After a 20 min survival period, left duras showed 55% with MC degranulation (fewer with complete degranulation) compared to 34% on the right. In the other experiments two parallel lines were scored following the injection of Evan's blue. Histamine assay showed histamine increased in the left cortex to 154% at 5 min, 174% at 10 min, and 151% at 20 min. Fluorescent quantitation of extravasated Evan's blue at 20 min following the trauma gave an increase of 1385% over the value measured for the right cortex. Zolantidine, a selective histamine H2 receptor antagonist, administered at 10- and 20- mg/kg 30 min before the trauma blocked 65% of the Evan's blue extravasation compared with the control and 2.5 mg group.
444

The evaluation of ultrasonographic findings in the management of plantar fasciitis in runners and the association with clinical findings

Dunn, Shoshanna Lee January 2005 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2005. Thesis (M.Tech.: Chiropractic)-Dept. of Chiropractic, Durban Institute of Technology, 2005 xiv, 99 leaves / Plantar Fasciitis (PF), also called ‘the painful heel syndrome’, is a common cause of heel pain (Barrett and O’Malley, 1999:2200), accounting for between 7% and 10% of all running injuries (Batt and Tanji, 1995:77; Chandler and Kibler, 1993:345). Primarily an overuse injury, resulting from tensile overload, it involves inflammation and micro-tears of the plantar fascia at its insertion on the calcaneus (Lillegard and Rucker, 1993:168; Barrett and O’Malley, 1999:2200). The body’s attempt to heal these micro-tears leads to chronic inflammation and the formation of adhesions (Ambrosius and Kondracki, 1992:30). Transverse friction massage has been found to be beneficial in the treatment of PF (Hyde and Gengenbach, 1997:478,481; Hertling and Kessler, 1996:137). Cyriax (1984) and Prentice (1994) state the effect of frictions to include the breakdown of adhesions (scar tissue), as well as preventing the formation of further adhesions. Graston Technique Instrument-assisted Soft Tissue Mobilisation (GISTM), based on the principles of frictions, aims to break down adhesions, realign collagen fibres and aid in the completion of the inflammatory process (Carey-Loghmani, 2003:31, 51-62; Hammer, 2001). Enabling us to see changes on ultrasonography, which has been found to be an objective, non-invasive way of evaluating PF (Wall and Harkness, 1993:468; Tsai et al, 2000:259; Cardinal et al, 1996:258). These changes include decreased thickness of the fascia. The aim of the study was to see the effect of GISTM on PF in runners, in terms of ultrasonography, and identify any correlation between these findings and other objective and subjective findings. / M
445

The Role of Injury-related Injustice Perception in Adjustment to Spinal Cord Injury: an Exploratory Analysis

Garner, Ashley Nicole 12 1900 (has links)
Research has begun to explore the presence and role of health-related injustice perceptions in samples of individuals who experience chronic pain associated with traumatic injury. Existing studies indicate that higher level of injustice perception is associated with poorer physical and psychosocial outcomes. However, to date, few clinical populations have been addressed. The aim of the current study was to explore injustice perceptions in a sample of individuals who have sustained a spinal cord injury (SCI), as research suggests that such individuals are likely to experience cognitive elements characteristic of injustice perception (e.g., perceptions of irreparable loss, blame, and unfairness). The study explored the relationship between participants’ level of perceived injustice and several variables associated with outcomes following SCI (depression, pain, and disability) at initial admission to a rehabilitation unit and at three months following discharge. The Injustice Experience Questionnaire was used to measure injustice perceptions. IEQ was found to significantly contribute to depression and anger at baseline. IEQ significantly contributed to depression, present pain intensity, and anger at follow-up. The implication of these preliminary findings may be beneficial for development of future interventions, as many individuals in the United States experience the lifelong physical and psychological consequences of SCI at a high personal and public cost.
446

An investigation into the effectiveness of dry needling of myofascial trigger points on total work and other recorded measurements of the vastus lateralis and vastus medialis muscles in patellofermoral pain syndrome in long distance runners

Weyer-Henderson, Donna January 2005 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2005. / According to Wood (1998), patellofemoral pain syndrome (PFPS) refers to a syndrome that comprises of the following signs and symptoms: anterior knee pain, inflammation, imbalance, instability, or any combination thereof. Prevailing literature suggests that the presence of myofascial trigger points (MFTP’s) in quadriceps femoris (QF) muscle could result in a combination of the following signs and symptoms: - Retro- or peripatella pain, - Weakness of the quadriceps muscle (Chaitow and DeLany, 2002) - Loss of full lengthening (Travell and Simons, 1983:248-250) The aetiology of PFPS is poorly understood (Kannus et al. 1999). The current trend in literature suggests an extensor mechanism dysfunction as the most probable aetiology (Galantly et al., 1994; Juhn, 1999). There appears to be a clinical overlap between the two syndromes, in terms of an extensor mechanism dysfunction and of signs and symptoms. The aim of this investigation was to evaluate the role of active myofascial trigger points in the vastus lateralis (VL) muscle as perpetuating, causative or concomitant factors in the alteration of VL/VM Total Work (TW) in PFPS in distance runners.
447

The relative effectiveness of muscle energy technique compared to manipulation in the treatment of chronic stable ankle inversion sprains

Joseph, Lynette Colleen January 2005 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2005. / An inversion ankle sprain can be defined as an injury caused by landing forcefully on an inverted, plantarflexed and internally rotated foot. This results in the fibres of the surrounding ligaments to become ruptured without disturbing the continuity of the ligament. Chronic stable ankle sprains was defined as the recurrent giving way of the ankle and there may be residual pain and swelling with no mechanical instability. According to literature, mechanisms involved in the development of chronic ankle sprains are: the lack of appropriate and early immobilization in severe cases, the development of scar tissue, lack of strengthening exercises or the development of hypermobility. Many treatments have been suggested to address these factors and would include: peripheral manipulation of the ankle joint, Muscle Energy Technique, muscle strengthening and stretching, proprioceptive training and deep transverse friction massage. Of the above mentioned treatments, Muscle Energy Technique has not been researched in a clinical setting for the treatment of chronic stable ankle inversion sprains. Therefore the purpose of this study was to investigate the relative effectiveness of Muscle Energy Technique compared to Manipulation in the treatment of chronic stable ankle inversion sprains. / M
448

The relationship between myofascial trigger points, total work and other recorded measurements of the vastus lateralis and vastus medialis, in long-distance runners with patellofermoral pain syndrome

Daly, Gail January 2005 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, 2005. / To document the relationship between total work and myofascial trigger points in the vastus lateralis and vastus medialis portion of the quadriceps femoris muscle, whilst providing baseline graphs of these muscles with the use of a Cybex 700 Isokinetic Dynanometer in long distance runners both with and without patellofemoral pain syndrome. Methods: A quantitative, non-intervention clinical exploratory study. Fifty participants were divided into two groups, Group A (40 symptomatics) and Group B (10 asymptomatics). Both groups were screened for vastus lateralis and vastus medialis trigger points. Subjective data was obtained from Group A only, using the Numerical Pain Rating Scale and the Patient Specific Functional Scale. Objective data was obtained from both groups using the algometer, Myofascial Diagnostic Scale, and the Cybex 700 Isokinetic Dynanometer. For descriptive analysis frequency tabulations, box and whisker plots were used to display distributions graphically. Comparisons of categorical and quantitative variables between independent groups were run using chi square and Mann-Whitney testing consecutively. Finally Spearman’s correlation, multivariate generalized linear modelling and repeated measures ANOVA were also used. All statistical analysis was completed at the 95% (p<0.05) level of confidence. / M
449

The effect of ankle joint manipulation on peroneal and soleus muscle activity in chronic ankle instability syndrome

Dicks, Jason January 2016 (has links)
Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2016. / Purpose: Ankle sprains are amongst the most common injury sustained by athletes and the general public. When an ankle is repeatedly sprained it results in chronic ankle instability syndrome (CAIS). This repeated trauma results in disruption of the afferent nerve supply from the injured joint, which affects the motor neuron pool excitability of the peroneal and soleus muscles resulting in arthogenic muscle inhibition (AMI). Traditional treatment for CAIS focuses on rehabilitation of the affected muscles via strength and proprioceptive training. Recent literature has shown that the addition of ankle joint manipulation resulted in improved clinical outcomes in the treatment of CAIS. The mechanism on how joint manipulation affects AMI is under-investigated especially in extremity joints. Thus this study aimed to determine the immediate effect of ankle joint manipulation on peroneal and soleus muscle activity, by assessing surface electromyography (sEMG) H/M ratio to detect a change in the proportion of the total motor neuron pool being recruited, in participants with CAIS. Methods: The study utilised a quantitative, experimental, pre-test post-test study design. Forty two participants with grade I and II CAIS, aged 18-45 years, were randomly allocated into one of three groups. Group one received a single talocrural joint long axis distraction manipulation, group two received a sham manipulation and group three was the control receiving no intervention. sEMG H/M ratio measurements were taken before and immediately after the intervention using a Biopac wireless emg system. Results: The groups were comparable at baseline for age, gender, body mass index and H/M ratio measurements for the soleus and peroneal muscles (p < 0.050). Intra-group analysis of the soleus muscle H/M ratio showed no statistically significant change over time for the manipulation (p = 0.975) and sham (p = 0.056) groups, with the control group showing a statistically significant (p = 0.019) decrease in the H/M ratio. For the peroneal muscle no statistically significant (p > 0.050) differences were observed in any of the three groups. Inter-group analysis of the soleus muscle H/M ratio measurements showed no statistically significant differences between the three groups (p = 0.470; F = 1.010) over time, with Tukey’s HSD post-hoc test revealing a statistically significant (p = 0.028) difference being observed between the sham and control groups in terms of post soleus muscle H/M ratio measurements. Conclusion: This study failed to show that ankle joint manipulation affects the soleus and peroneal muscles in terms of H/M ratio measurements in participants with CAIS. There may have been a trend of an effect of the sham and manipulation interventions counteracting the muscle fatigue experienced in the control group, however further investigation is required. / M
450

A retrospective cross-sectional survey of lumbo-sacral cases recorded at the D.U.T. Chiropractic Day Clinic (1995-2005)

Jaman, Ravina January 2007 (has links)
A dissertation submitted in partial compliance with the requirements for a Master's Degree in Technology: Chiropractic, Durban University of Technology, 2007. / To determine the prevalence and demographics of lumbo-sacral cases recorded at the D.U.T Chiropractic Day Clinic from 13th January 1995 to 30th November 2005. To identify the aetiology, common lumbo-sacral diagnoses, associated signs and symptoms, management and contra-indications to chiropractic treatment recorded on the initial consultation of patients with lumbo-sacral complaints. / M

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