Tesi: "Musculoskeletal system – Wounds and injuries"

1

林玊玲 e Yuk-ling Lam. "Patterns of musculoskeletal injuries in collegiate dancers". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31257264.

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Cogger, Naomi. "Epidemiology of musculoskeletal injuries in two- and three-year-old Australian Thoroughbred racehorses". University of Sydney, 2006. http://hdl.handle.net/2123/1611.

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Doctor of Philosophy
The aim of this research was to describe the epidemiology of musculoskeletal (MS) injuries in two- and three-year-old Thoroughbred racehorses. A 27 month longitudinal study commencing in May 2000 was conducted. The study convenience sampled 14 trainers with facilities at metropolitan and provincial racetracks in New South Wales, Australia. In the 2000/01 and 2001/02 racing season, 323 and 128 two-year-olds, respectively, were enrolled in the study. The 451 Thoroughbred horses contributed, 1, 272 preparations and 78, 154 training days to the study. Of the 323 horses enrolled in the 2000/01 racing season, 219 contributed three-year-old data to the study. During the study period 8%, of training days had missing training data and 3% of the 1, 986 starts in the races or barrier trials were incorrectly recorded. The rate of incorrect entries varied with both study month and trainer. Similarly, the rate of training days with missing data varied between trainers and with study month. Four hundred and twenty-eight MS injuries were recorded in association with 395 preparations in 248 two- and three-year-old Thoroughbred racehorses. The IR for all categories of MS injuries, except for tendon and ligament injuries, were higher in twoyear- olds than three-year-olds, although the differences were only significant for shin soreness. Seventy-eight percent of horses enrolled in the study started, in a barrier trial or race, within one year on entering the study. After accounting for other confounders, horses that had sustained a MS injury were 0.50 times less likely to start, in a race or trial, race than those that did not sustain an injury. Seventy percent of horses returned to training after their first MS injury, and the cumulative percentage of these horses that had recovered within six months of the initial MS injury was 55%. After adjusting for clustering at the level of the trainer, the analysis showed that horses that exercised at a gallop pace ≥ 890 m/minute (but had not started in a race) prior to the onset of MS injury, were 2.14 times more likely to recover than horses whose maximum speed, prior to the onset of the first MS injury, was less than 890 m/minute. Similarly, horses that had started in a race or barrier trial were 4.01 times more likely to recover than horses whose maximum speed was less than 890 m/minute. 8 Training days were grouped into units referred to as preparations. A preparation began on the day that the horse was enrolled in the study, or when a horse returned to training after an absence of more than seven days from the stable. The preparation continued until the horse was lost to follow-up or left the stable for a period of more than seven consecutive days. Univariable and multivariable analytical methods were used to examine the association between a range of independent variables and four preparationlevel measures of performance: (i) the duration of preparations, (ii) length of time from the beginning of the preparation until the first start in a race or barrier trial, (iii) length of time from the first start until the end of the preparation and (iv) rate of starts in races or barrier trials. After adjusting for confounders, younger horses tended to have shorter preparations, took longer to start in a race or barrier trial, had a shorter interval from the first start to the end of the preparation and fewer starts per 100 training days. MS injury was not conditionally associated with any of the outcomes considered in this chapter. Multivariate statistical models were used to explore risk factors for MS injuries. The results suggest that MS injuries involving structures in the lower forelimb (carpus to fetlock inclusive) could be reduced by limiting exposure to high-speed exercise. This supports the proposition that training injuries are caused by the accumulation of micro damage. The results suggest there are a number of other factors that vary at the trainer level that may be risk factors for injuries, in particular joint injuries. These include unmeasured variables such as the rate of increase in distance galloped at high-speed, conformation of the horse, skill of the riders and farrier and veterinary involvement.

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Allsop, Li Li. "Investigating the prevalence of playing-related musculoskeletal disorders in relation to piano players' playing-techniques and practising strategies". University of Western Australia. School of Human Movement and Exercise Science, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0090.

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This study placed specific emphasis on the motor-skills and practice strategies employed by piano players when practising and performing in relation to playing-related musculoskeletal disorders (PRMDs). The survey questionnaire-instrument was designed by the researcher to investigate the prevalence of PRMDs among both professional and non-professional piano players. Five hundred and five respondents completed the self-administered survey questionnaire. Out of the total 505 participants, 42% of the players reported PRMDs. The professional players (72%) reported a significantly higher incidence (p < 0.05) of PRMDs in comparison with the non-professional group. The professional players with piano as their major instrument, using predominantly neutral wrist posture (i.e., open-kinetic chain playing technique), reported a significantly higher incidence of PRMDs. Although the present study showed a greater number of years of playing was associated with greater risk of PRMDs, the result also showed that the years of playing had no significant effect on the incidence of PRMDs (p > .05) when it was analyzed with the practice hours within seven days. Moreover, analyzing the practice hours over seven days with the piano major/non-major instrument, the various grade levels and PRMDs; the results showed that the practice hours had no significant effect on the groups with and without PRMDs (p > .05). Although women reported a significantly higher percentage of PRMDs (p < 0.05) than men, there was no significant association between the groups with and without PRMDs when analyzing practice hours over seven days by grade levels and gender. The PRMDs seem to arise when overuse is compounded by misuse and/or adverse playing conditions. The best and safest practice would be to minimize consumption of musculoskeletal force production and combine this with effective practice-breaks between sessions to achieve the optimum goal of daily practice. Keywords: hand injury, PRMDs, wrist pain, hand-span size, playing-technique, and piano player.

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Liu, Ming-chi, e 廖明志. "Musculoskeletal injuries resulting from manual handling in health caresettings: a review of effectiveness forprevention programs". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45173229.

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5

Sheppard, Bronwyn Jane. "Musculoskeletal and perceptual responses of batsmen comparing high- and moderate-volume sprints between the wickets". Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1016366.

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Background: Literature has associated repeated eccentric muscle actions with increased muscle damage of the muscles involved. Eccentric actions are typical in sports which are ‘stop-start’ in nature requiring rapid acceleration and deceleration, typical of a batting activity in cricket. Ultra-structural damage of the skeletal muscle as a consequence of repeated decelerating activities is associated with performance decrements, particularly muscle strength and sprinting speeds. This suggests that eccentric strength decrements may provide an indication for the development of muscle strain injuries during these activities. Despite these findings, limited research has identified the specific musculoskeletal demands placed on cricket batsmen, particularly with reference to various match intensities. Objective: The present study, therefore, sought to determine the specific musculoskeletal, physiological and perceptual demands placed on specialised batsmen during two work bouts of different intensities; one representing a highintensity work bout and the other a moderate-intensity work bout. The dependent variables of interest were muscle activation, isokinetic strength changes, heart rate, ‘central’ and ‘local’ ratings of perceived exertion (RPE), body discomfort and performance. Methods: The two experimental conditions, representative of a high- (HVR) and moderate-volume running (MVR) batting protocol, required players to perform a simulated batting work bout of either twelve or six runs an over, within a laboratory setting. Selected physiological, perceptual and performance measures were collected at specific time intervals throughout the work bout while the biophysical measures were collected prior to, and following both protocols. Results: Of the variables measured, heart rate, ‘central’ and ‘local’ RPE values were observed to increase significantly (p<0.05) over time. This increase was greater as a consequence of the HVR in comparison to the MVR. No change in sprint times was documented during the MVR, in contrast, significant (p<0.05) increases over time were observed during the HVR, further highlighting the elevated demands associated with this condition. In addition, an ‘end spurt’ was observed particularly following the HVR condition, suggesting athletes were conserving themselves through the adoption of a pacing strategy. Reductions in biceps femoris and semitendinosus muscle activation levels were observed following the HVR. This was further supported by the significantly greater levels of semitendinosus activation following the MVR when compared to the HVR. Peak concentric and eccentric knee extensor (EXT) (-17.17% and -16.07% respectively) and eccentric flexor (FLEX) (- 17.49%) values decreased significantly (p<0.05) following the HVR at 60°.s-1. In addition, concentric and eccentric total work produced by the flexors and eccentric extensors resulted in significantly (p<0.05) lower values due to the HVR. Conclusion: The intermittent high-volume batting work bout elicited elevated mean heart rates, perceived ratings of cardiovascular and muscular effort and sprint times. Furthermore, hamstring activation levels and muscle strength, particularly concentric strength of the dominant lower limb were negatively affected by the HVR condition. These results suggest elevated demands were placed on the hamstring musculature as a consequence of the HVR condition, indicating a greater degree of musculoskeletal strain and increased injury risk associated with running between the wickets at this intensity, representative of an aggressive batting scenario.

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Wilson, Rhoda M. "An innovative approach for assessing the ergonomic risks of lifting tasks using a video motion capture system". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Mar%5FWilson.pdf.

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Thesis (M.S. in Human Systems Integration)--Naval Postgraduate School, March 2006.
Thesis Advisor(s): Michael McCauley. "March 2006." Includes bibliographical references (p. 49-51). Also available online.

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Kelly, Patricia J. "Morphological changes of collagenase induced tendinitis of achilles rat tendons utilizing augmented soft tissue mobilization". Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1129629.

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Augmented Soft Tissue Mobilization (ASTM) is a new noninvasive technique utilized to treat chronic musculoskeletal injuries. The purpose of this study was to trace the morphological events in collagenase injured rat Achilles tendons during ASTM treatment and to observe passive occurrence of post treatment remodeling in tendons. Twelve groups of rats were divided into the following categories, A) control, B) sham surgery, C) ASTM only, D) ASTM/sham , E) tendinitis, F) ASTM/tendinitis 1 week, G) ASTM/tendinits 2 weeks H) ASTM/tendinits 3 weeks I) ASTM/tendinits 4 weeks, J) Post ASTM 5 weeks, K) Post ASTM 10 weeks, L) Post ASTM 15 weeks. One week after the last designated treatment, the Achilles tendons were harvested and then prepared for light microscopy, electron microscopy, and bifringence polarizing microscopy. An increase in fibroblast activation and proliferation was noted with the tendinitis, ASTM/tendinitis, and post groups. Ossification occurred in the core of the Achilles tendon in all of the ASTM groups. The presence of inflammatory cells was observed in the tendons and longitudinal remodeling of the collagen fibers did not occur.
Department of Biology

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8

Brusky, Paula. "Performance Related Musculoskeletal Disorders in Bassoon Players". University of Sydney, 2009. http://hdl.handle.net/2123/5136.

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PhD in Performance
Performance related musculoskeletal disorders (PRMDs) are a frequent reality for practicing musicians. Many aspects of the bassoon make bassoon players particularly susceptible to PRMDs. This thesis explored the prevalence of PRMDs among bassoon players and assessed the frequency, types, and locations of PRMDs. Also identified were treatments used for PRMDs, contributing factors to PRMD development, and the perceptions of the bassoon community regarding PRMDs. The International Bassoonist Questionnaire was distributed via the World Wide Web (n = 166, 58% male, 42% female). Eighty-six percent of bassoon players reported PRMDs. Pain was the most common PRMD symptom reported (78%). Females reported PRMDs (96%) more frequently than males (78%). Younger bassoon players reported more PRMDs. Most bassoon players (88%) were attempting to treat their PRMDs. The most common self-administered treatments were rest (60%) and reducing playing time (53%). Bassoonists attributed the cause of PRMDs to “long hours of practice” and “sudden increase in playing time.” Bassoon players felt strongly that the medical profession did not know how to treat a bassoon related injury. They believed that a knowledgeable teacher was the best resource against the onset of PRMDs even though technical aspects of playing were not identified as significant contributors to PRMDs. The bassoon playing population needs more information about PRMDs in order to develop treatment and prevention strategies.

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Jacka, Karen-Louise. "The effect of work-hardening on the physical work capacity of manual labourers within South African industry". Thesis, Rhodes University, 1997. http://hdl.handle.net/10962/d1016237.

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South Africa is a labour-intensive industrially developing country. As a result, in excess of 200 000 workers suffer from musculoskeletal injuries in a year. Research is thus essential to develop more effective strategies in the reduction and rehabilitation of occupational musculoskeletal disorders within industry. It was the hypothesis of this study that by improving the physical work capacity of manual labourers, through participation in an occupation specific work-hardening programme, that the ergonomic stress index and therefore the occurrence of musculoskeletal injuries within industry, may be reduced. Twenty-five male Black and Coloured manual labourers volunteered to participate in this study. In addition to in situ task analyses, the subjects participated in cardiovascular and strength assessments in the laboratory, both pre- and post-participation in the ten-week work-hardening programme. The data were statistically analyzed in order to identify any significant • improvements in the workers' physical work capacity, as measured by cardiovascular, strength and perceptual responses, following the period of work-hardening. Two significant reductions were noted in measures of working heart rate together with significant improvements in grip strength and trunk strength tested at a velocity of 60°.sec·1 at the post-conditioning assessments. In conclusion, the ten-week work-hardening programme resulted in nominal improvements in all the cardiovascular measures and significant improvements in the subjects' strength performance. However, industrialists must recognise that this study dealt with only one aspect of reducing the ergonomic stress index at the workplace and realise that, in addition to this focus, it remains essential to design the task to fit the human operator.

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Menzel, Nancy Nivison. "Manual Handling Workload and Musculoskeletal Discomfort in Nursing Personnel". [Tampa, Fla. : s.n.], 2001. http://purl.fcla.edu/fcla/etd/SFE0000020.

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11

Bauman, Jay Morris. "Injury compensation reveals implicit goals that guide locomotor coordination". Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/51737.

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Locomotion persists despite changes in external and internal circumstances. Motor responses to gait impairment exhibit commonalities across various taxa and types of injury, yet we lack a systematic understanding of compensation strategies. The objective of this dissertation is to uncover principles governing implicit goals within the control of locomotion. I propose that coordination of injured locomotion will demonstrate that these goals follow a hierarchical organization of the neuromuscular system. Accurate quantification of gait deficits in rodents demands sophisticated measurement techniques. I utilize X-ray technology to examine intralimb and interlimb coordination after unilateral injury in rats. My findings indicate that compensation to injury involves the coordination of lower-order motor elements to preserve the pre-injury behaviors of higher-order elements. Specifically I present evidence that preservation of limb angle and limb length are critical task goals that transcend injury states and afferent sensory feedback conditions. Broadening my investigation to include interlimb coordination revealed that task goals may change to satisfy the goals of a higher hierarchical level. This work is a necessary precursor to study locomotor coordination and injury compensation in more complex rodent injury models such as self-reinnervation, sciatic nerve, and spinal cord injury. These results could also translate to clinical gait rehabilitation through future protocols that address motor patterns of the entire limb over the behavior of individual joints.

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Van, Vledder Nicole. "An ergonomic intervention : the effect of a chair and computer screen height adjustment on musculoskeletal pain and sitting comfort in office workers". Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96865.

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Thesis (MScPhysio)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Aims: To assess the effect of a vertical height adjustment of the chair and visual display unit (VDU) on work related upper quadrant musculoskeletal pain (WRUQMP) and sitting comfort in computer users. The upper quadrant refers to the occiput, cervical and upper thoracic spine including the clavicles and scapulae. Methods: An N=1 study was conducted using the ABC design whereby an ergonomic workstation adjustment, of VDU and chair height, was compared to the subject’s usual workstation settings. Pain and sitting comfort were measured using visual analogue scales (VAS). The subject was assessed over the four week phases as she performed her typical VDU work. The results were compiled and tabulated. Results: Both the mean and variance in pain intensity decreased after the workstation intervention. A deterioration was noted in sitting comfort. Conclusion: The vertical height adjustment of the chair and VDU may have contributed to a decrease in WRUQMP in this subject. This safe, economical workstation intervention may be a practical management option for the computer user suffering from WRUQMP. Further research into the measurement of comfort whilst sitting at a computer workstation, is recommended.
AFRIKAANSE OPSOMMING: Doelwitte: Om die effek te bepaal van n vertikale aanpassing van die stoel en beeldskerm van rekenaargebruikers op werksverwandte boonste kwadrant muskuloskeletale pyn en sitgemak. Die boonste kwadrant verwys na die oksiput, servikale en boonste torakale werwelkolom en sluit ook die klavikel en skapula in. Methode: Die N=1 studie is onderneem met gebruik van die ABC ontwerp in terme waarvan n ergonomiese aanpassing van stoel en beeldskerm vergelyk is met die normale gebruik van die deelnemer. Pyn en sitgemak is gemeet deur die gebruik van die Visueel analoogskaal. Die interwensies is ge-evalueer oor vierweekfases tydens normale rekenaar gebruik van die deelnemer. Die resultate is saamgestel en getabuleer. Uitkoms: Beide die gemiddelde en veranderlike pynintensiteit het verminder nadat die werkstasie aangepas is. Geen verbetering in sitgemak is opgemerk nie. Gevolgtrekking: Die vertikale hoogte-aanpassing van die stoel en beeldskerm het moontlik bygedra tot die verminderde pynvlakke in hierdie deelnemer. Hierdie veilige, ekonomiese verstelling is moontlik n praktiese beheeropsie vir rekenaargebruikers wat werksverwandte boonste kwadrant muskuloskeletale pyn verduur. Verder studie in die meet en waarneming van sitgemak tydens rekenaarwerk is nodig.

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Bennett, Anthea Iona. "The effect of load and technique on biomechanical and psychophysical responses to level dynamic pushing and pulling". Thesis, Rhodes University, 2009. http://hdl.handle.net/10962/d1005188.

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Pushing and pulling research has yet to fully elucidate the demands placed on manual workers despite established epidemiological links to musculoskeletal disorders. The current study therefore aimed to quantify biomechanical and perceptual responses of male operators to dynamic pushing and pulling tasks. Three common push/pull techniques (pushing, one handed and two handed pulling) were performed at loads of 250kg and 500kg using an industrial pallet jack in a laboratory environment. Thirty six healthy male subjects (age: 21 ±2 years, stature: 1791 ±43 mm and body mass: 77 ±10 kg) were required to perform six loaded experimental and two unloaded control conditions. Hand force exertion, muscle activity and gait pattern responses were collected during 10m push/pull trials on a coefficient controlled walkway; body discomfort was assessed on completion of the condition. Horizontal hand force responses were significantly (p<0.05) affected by load, with a linear relationship existing between the two. This relationship is determined by specific environmental and trolley factors and is context specific, depending on factors such as trolley maintenance and type of flooring. Hand force exertion responses were tenuously affected by technique at higher loads in the initial and sustained phases, with pushing inducing the greatest hand forces. Comparison of the motion phases revealed significant differences between all three phases, with the initial phase evidencing the greatest hand forces. Muscle activity responses demonstrated that unloaded backward walking evoked significantly higher muscle activation than did unloaded forward walking whilst increased muscular activity during load movement compared to unloaded walking was observed. However increasing load from 250kg to 500kg did not significantly impact the majority of muscle activity responses. When considering technique effects on muscle activity, of the significant differences found, all indicated that pushing imposed the least demand on the musculoskeletal system. Gait pattern responses were not significantly affected by load/technique combinations and were similar to those elicited during normal, unloaded walking. Perceptually, increased load led to increased perception of discomfort while pushing resulted in the least discomfort at both loads. From these psychophysical responses, the calves, shoulders and biceps were identified as areas of potential musculoskeletal injury, particularly during one and two handed pulling. Pushing elicited the highest hand forces and the lowest muscle activity responses in the majority of the conditions whilst psychophysical responses identified this technique as most satisfactory. Current results advocate the use of pushing when moving a load using a wheeled device. Suitability of one and two handed pulling remains contradictory, however results suggest that one handed pulling be employed at lower loads and two handed pulling at higher loads.

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Loos, Benjamin. "Signalling mechanisms involved in TNF-α mediated cytoprotection during ischaemic injury in a C2C12 muscle cell line". Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/17377.

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Thesis (MSc)--University of Stellenbosch, 2006.
ENGLISH ABSTRACT: Both, the cytokine Tumor Necrosis Factor-α (TNF-α) and the enzyme cytosolic phospholipase A2 (cPLA2) are crucial driving forces in mediating the cellular inflammatory response and are involved in ischaemic injury. During an ischaemic insult, TNF-α is endogenously generated. Apart from the recognized effects of TNF- α, such as the induction of apoptosis, proliferation and differentiation, if present in low dosages, it also mediates cytoprotective effects. Upon activation, cPLA2 contributes to the ischaemic challenge with the generation of mediators of cellular injury and apoptosis. Upon stimulation, this calcium dependent enzyme translocates to the phospholipid compartment of the cell membrane and induces the hydrolysis of sn-2 ester bonds in phospholipids. It governs the release of free fatty acids and lysophospholipids and generates role players of inflammation. We suggest a role for cPLA2 in the TNF-α mediated cytoprotection, with a distinct phosphorylation and translocation pattern. Aims The involvement of cPLA2 in TNF-α mediated cytoprotection in the C2C12 murine skeletal muscle cell line in tolerance to ischaemia was examined. To investigate the nature of the cPLA2 phosphorylation pattern, the mitogen activated protein kinases (MAPKs) p38 and extracellular regulated kinase (ERK) as contributors to cPLA2 phosphorylation and activation, were examined at appropriate time points. To dissect out the cPLA2 interplay and dependencies with these MAPKs within the pathway context, the selective cPLA2 inhibitor arachidonyl trifluoromethyl ketone (AACOCF3) was employed and its effect on cell viability was examined. Fluorescence microscopy was used to substantiate cPLA2 activation, by assessing its cellular distribution, translocation and cell organelle target preference, using co-localization and z-stack techniques. In addition, the induction of the apoptotic pathway through analysis of caspase-3 and poly (ADP-ribose) polymerase (PARP) cleavage was examined. The role of caspase-3 in cPLA2 turnover was addressed employing the caspase inhibitor, Z-DEVD-FMK. Methods Cells were grown in Dulbecco’s Modified Eagles Medium (DMEM) with 10% fetal bovine serum (FBS), and incubated under 5% CO2 conditions, until 50%-70% confluent. Using DMEM supplemented with 1% horse serum, cell differentiation into myotubes was induced. Differentiated cells were preconditioned for 30 min classically, with 0.5 ng/ml TNF-α or the cPLA2 selective inhibitor AACOCF3 (10 μM) respectively. Followed by a 60 min washout period the cells were subjected to 8 hrs simulated ischaemia. Cellular viability; and cPLA2 phosphorylation- and translocation events were assessed using Western blots and advanced immunocytochemistry and imaging techniques. Results Preconditioning with TNF-α, ischaemic preconditioning; and the use of the cPLA2 inhibitor AACOCF3, attenuated the decrease is cell viability brough about by ischaemia. Western blot analysis indicates the induction of the apoptotic pathway with caspase-3 and PARP cleavage. A significantly reduced translocation of pcPLA2 to the nuclear region in the TNF-α preconditioned group compared to the ischaemic group, as reflected by reduced mean nuclear fluorescence intensity, was observed. A z-stack analysis confirmed that the nuclear and endonuclear region was the target organelle for cPLA2. 3-dimensional co-localazation analysis of pcPLA2 with the nuclear marker nucleoporin p62 mirrored these results. Discussion and conclusion Our results provide evidence that there is a role for cPLA2 in TNF-α mediated cytoprotection. Although we do not observe a differential activation pattern in terms of cPLA2 phosphorylation at various time points within the ischaemic event, and no differential inactivation of cPLA2 via caspase-mediated cPLA2 cleavage, we describe a differential cPLA2 translocation pattern, similar to that in IPC. Through inhibition of cPLA2 translocation, a functional cPLA2 inhibition might be achieved. This would imply inhibition of the inflammatory pathway and a subsequent reduction in the generation of inflammatory mediators. In addition we describe an effect of TNF-α preconditioning on the efficacy of the caspase inhibitor Z-DEVD-FMK. Our results shed light on the survival mechanisms employed by the ischaemically challenged cell in a setting of TNF-α mediated cytoprotection. This might lead to novel approaches in the context of inflammation treatment, through agents that control differential cPLA2 trafficking within the cell.
AFRIKAANSE OPSOMMING: Beide, die sitokien “Tumor Necrosis Factor-α (TNF-α)” en die ensiem, sitosoliese fosfolipase A2 (cPLA2) is uiters belangrike bemiddelaars van die sellulêre inflammatoriese respons en is verder ook betrokke by isgemiese selskade. TNF-α word endogeen gegenereer tydens ‘n isgemiese intervensie. Afgesien van ‘n verskeidenheid effekte, soos die inisiëring van apoptose, sel-proliferasie en - differensiasie, bemiddel dit ook selbeskermende meganismes indien dit in lae konsentrasies in die sel teenwoordig is. Na aktivering dra cPLA2 by tot die isgemiese intervensie deur die vorming van bemiddelaars van selskade en apoptose. Hierdie kalsium-afhanklike ensiem translokeer na die fosfolipied membraankomponent na stimulering en induseer die hidrolise van die sn-2 esterbinding in die fosfolipied. Die vrystelling van vry vetsure en lisofosfolipiede word sodoende bewerkstellig wat verder gemetaboliseer kan word tot inflammatoriese bemiddelaars. Ons stel voor dat cPLA2 ‘n rol in TNF-α bemiddelde selbeskerming speel en dat dit gepaardgaan met kenmerkende fosforilerings- en translokeringspatrone. Doelwitte Die rol van cPLA2 tydens TNF-α bemiddelde selbeskerming is in ‘n C2C12 skeletspiersellyn na blootstelling aan isgemie ondersoek. Die rol van die MAPKs, p38 en ERK, is ondersoek om vas te stel of hulle betrokke is by die aktivering van cPLA2. Die selektiewe cPLA2 inhibitor, AACOCF3, is gebruik om te bepaal of die fosforilering van MAPKs ook cPLA2-afhanklik is. Die sellulêre cPLA2 verspreiding, translokering en teiken selorganelle is ook ondersoek met behulp van fluoresensie mikroskopie deur gebruik te maak van ko-lokalisering en z-plaat tegnieke. Verder, is die indusering van die apoptotiese paaie ondersoek deur tegnieke wat kaspase- en PARP kliewing meet. Die kaspase inhibitor, Z-DEVD-FMK, is gebruik om vas te stel of kaspase-3 ‘n rol speel in cPLA2 kliewing in ons selmodel. Metodes Selle is gekweek in Dulbecco’s gemodifiseerde Eagles Medium (DMEM) waarby 10% fetale kalf serum (FBS) gevoeg is, en wat geïnkubeer is in 5% CO2 totdat dit 50%-70% konfluent was. Die selle is verder gedifferensieer in miobuise deur gebruik te maak van DMEM waarby 1% perdeserum gevoeg is. Gedifferensieerde selle is vir 30 min klassiek geprekondisioneer asook respektiewelik met 0.5 ng/ml TNF-α en die cPLA2 selektiewe inhibitor, AACOCF3 (10 μM). Na ‘n 60 minute uitwas periode is die selle blootgestel aan 8 h gesimuleerde isgemie. Sellulêre lewensvatbaarheid, cPLA2 fosforilering- and translokering is ondersoek deur onderskeidelik gebruik te maak van die “Western” klad metode en gesofistikeerde immunositochemiese beeld tegnieke. Resultate Prekondisionering met TNF-α, isgemiese prekondisionering asook inhibisie van as cPLA2 met die inhibitor, AACOCF3, het ‘n beduidende toename in sellewensvatbaarheid tot gevolg gehad. Daar is ook dmv die “Western” klad tegniek bewys dat apoptose geïduseer word deur middel van kaspase-3- en PARP kliewing. Daar is insiggewend minder translokasie van cPLA2 na die nukluêre fraksie in die isgemiese groep in vergelyking met die TNF-α geprekondisioneerde groep waargeneem (die gemiddelde nukluêre fluoreserende intensiteit is bepaal om voorafgaande feit te staaf). Die cPLA2 teiken organel is geverifieer as die nukleus en die endonukluêre gebied deur middel van z-plaat analises. Drie-dimensionele kolokaliserings analises van pcPLA2 met die nukluêre merker, nucleoporin p62 het hierdie resultate bevestig. Bespreking en Gevolgtrekking Ons resultate verskaf bewyse vir ‘n rol vir cPLA2 in TNF-α bemiddelde selbeskerming. Alhoewel daar nie ‘n differensiële aktiveringspatroon in terme van cPLA2 fosforilering tydens verskeie tydspunte in die isgemiese intervensie waargeneem is nie, en ook geen kaspase-3 bemiddelde kliewing van cPLA2 nie, word ‘n differensiële translokeringspatroon soorgelyk aan die isgemiese prekondisioneringsgroep, waargeneem. Funsksionele cPLA2 inhibisie kan dus moontlik bewerkstellig word deur inhibisie van cPLA2 translokasie. Die inflammatoriese respons kan dus moontlik so inhibieer word en die vorming van minder inflammatoriese bemiddelaars tot gevolg hê. Verder het TNF-α prekondisionering ook ‘n effek op die effektiwiteit van die kaspase-inhibitor, ZDEVD- FMK. Ons resultate werp ook lig op die meganismes wat deur selle onder isgemiese toestande uitgeoefen word tydens TNF-α bemiddelde selbeskerming. Hierdie resultate mag lei tot nuwe benaderings in die konteks van behandeling teen inflammasie deur gebruik te maak van middels wat cPLA2 translokering in die sel beheer.

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Wolfe, Amy. "The effect of restricted environments on selected postural, physiological and perceptual responses". Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1005193.

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Manual lifting tasks are the predominant means of transporting materials in industry with many of these tasks being performed in confined spaces. Research has tended to focus on the biomechanical implications of working in small spaces with a decided lack of information about the physiological and perceptual responses in these environments. This holistic study therefore investigated the manner in which the human operator responded to conditions where the ceiling height was lowered and reach demands increased. Thirty-two young physically active male subjects (age: 21.55yr; stature: 1810mm) were recruited to complete a 2-way repeated measures experiment during which four lifting protocols where different combinations of ceiling height (‘normal’ or reduced to 1460mm in height) and reach demands (400mm or 800mm) were tested. A crude postural analysis was conducted while physiological responses were detailed and continuously monitored. Perceptual responses were also assessed. The tasks with a ‘normal’ ceiling height (mean compression forces: 2615N; mean shearing forces: 388N) and the greatest reach distance (mean compression forces: 3655N; mean shearing forces: 386N) placed individuals under the highest strain. Mean heart rate (HR) responses were significantly lower (p < 0.05) in the URN condition when compared to the RF condition. Furthermore, HR responses were statistically significantly affected by the height of the ceiling and the reach depth. Statistically significant differences (p< 0.05) in mean tidal volume (VT) occurred in the least (URN) and most (RF) restrictive conditions. Statistically significant differences (p < 0.05) in mean VE were evident between URN and URF, between URN and RF and between RN and RF. Ceiling height and reach demands had a statistically significant effect on all respiratory responses. There was a statistically significant difference in mean oxygen consumption (VO2) between the URN and all other conditions, and between the most restricted task (RF) and all other conditions. Both the effect of ceiling height and reach demands had a statistically statistically significant impact on VO2. Respiratory quotient (RQ) was significantly higher when loads were moved over 800mm compared to 400mm yet ceiling height did not have a statistically significant effect on RQ. Mean energy expenditure was significantly higher in the RF condition compared to the two least restrictive conditions (URN and RN). Statistically significant differences in EE were also evident between URN and RN, and between URN and URF. EE was significantly affected by reductions in ceiling height and increases in reach demands. Perceptually, the RF task (mean ‘Central’ RPE of 11) was perceived to place significantly greater cardiorespiratory demands on the operator compared to the URN (CRPE: 10) and RN (CRPE: 10) conditions. Statistically significant differences in perceived musculoskeletal strain only occurred between URN and RF. The effect of reach was perceived to have a statistically significant effect on both cardiovascular and musculoskeletal demands whereas ceiling height only had a statistically significant effect on musculoskeletal demands. The greatest discomfort was experienced in the lower back with the most intense discomfort occurring in the RN condition.

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Saggu, Rajinder Kaur. "Effect of a chair and computer screen height adjustment on the neck and upper back musculoskeletal symptoms in an office worker". Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96971.

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Thesis (MScPhysio)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Aims: To assess the effect of a chair and computer screen height adjustment on the neck and upper back musculoskeletal symptoms in an office worker. Methods: An N=1 study was conducted using the ABC design. Ethics approval was obtained for the study and the participant provided informed written consent. The participant was assessed over three four week phases as she performed her habitual computer work. The outcome measures assessed during the three phases were the pain intensity and perceived sitting comfort. The three phases were named the baseline, intervention and wash-out phases. During the baseline phase, the outcome measures were obtained at the participant‟s habitual work station. The intervention phase involved a vertical adjustment of the chair and computer screen height. The wash-out phase allowed the participant to adjust the chair and computer screen height to their choice. A follow-up interview was conducted with the participant three months after completion of the study. The mean values and the ranges of the pain intensity and perceived comfort were obtained and compared. The data collected was captured on a Microsoft Excel 2010 spread sheet, where after the data was tabulated and presented graphically. Results: The mean pain intensity of the participant increased slightly during the intervention phase in comparison to the baseline phase, but remained stable during the wash-out phase. The mean perceived sitting comfort deteriorated initially during the intervention phase, but improved later during the intervention phase and showed greater improvement during the wash out phase. The perceived sitting comfort showed more improvement than the pain intensity during the washout phase. Both the pain intensity and perceived sitting comfort showed improvement at the three months follow up assessment, post completion of the study. Conclusion: The vertical height adjustment of the chair and the VDT did not improve the participant‟s pain intensity and perceived sitting comfort when compared to the participant‟s habitual workstation parameters. The findings do not favour the horizontal viewing angle. The findings of this study however support the use of „slightly below horizontal‟ viewing angle as being conducive to reduce the pain intensity and improve the sitting comfort of an office worker.
AFRIKAANSE OPSOMMING: Doelstelling: Om die effek te bepaal van die hoogte aanpassing van die stoel en rekenaarskerm op die nek en bo-rug muskuloskeletale simptome van 'n kantoorwerker. Metodes: „n N=1 studie was uitgevoer deur gebruik te maak van die ABC ontwerp. Etiese goedkeuring was verkry vir die studie en die deelnemer het ingeligte skriftelike toestemming verleen. Die deelnemer was ge-evalueer oor drie vier week-lange fases terwyl sy haar gewone rekenaarwerk verrig het. Die uitkomsmetings ge-evalueer tydens die drie fases was pyn intensiteit en waargenome sitgemak. Die drie fases was genoem die basislyn, intervensie en uitwas fases. Gedurende die basislyn fase was die uitkomsmetings by die deelnemer se gewone werkstasie ingevorder. Die intervensie fase het 'n vertikale aanpassing van die stoel en rekenaarskerm behels. Die uitwas fase het die deelnemer toegelaat om haar stoel en rekenaarskerm se hoogte aan te pas volgens haar keuse. 'n Opvolg onderhoud was gevoer met die deelnemer drie maande na die voltooiing van die studie. Die resultate was vasgelê op 'n Microsoft Excel 2010 data bladsy, waarna die data getabuleer en grafies uitgebeeld is. Resultate: Die gemiddelde pyn intensiteit van die deelnermer het effens toegeneem tydens die intervensie fase in vergelyking met die basislyn fase, maar het stabiel gebly tydens die uitwas fase. Die gemiddelde waargenome sitgemak het aanvanklik verswak tydens die intervensie fase, maar het later verbeter tydens die intervensie fase en het aangehou verbeter tydens die uitwas fase. Die waargenome sitgemak het groter verbetering getoon as die pyn intensiteit tydens die uitwas fase. Beide pyn intensiteit en waargenome sitgemak het verbetering getoon by die drie maande opvolg evaluasie, na voltooiing van die studie. Gevolgtrekking. Die vertikale hoogte aanpassing van die stoel en rekenaarskerm het nie die deelnemer se pyn intensiteit en waargenome sitgemak in vergelyking met die deelnemer se gewone werkstasie parameters verbeter nie. Hierdie bevindinge is nie ten voordeel van die horisontale kykhoek nie. Nietemin, ondersteun die bevindinge van hierdie studie die gebruik van die "effens onder die horisontale" kykhoek as bevorderend om die pyn intensiteit te verminder en die sitgemak van 'n kantoorwerker te verbeter.

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Bandeira, Fábio Henrique. "A termografia no apoio ao diagnóstico de lesão muscular no esporte". Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/886.

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Introdução: Lesões musculares são muito comuns e costumam afastar os atletas da prática esportiva, tornando-se um transtorno também aos clubes. Devido às suas características, o rúgbi é um dos esportes que mais ocasionam lesões. A lesão muscular apresenta uma variação térmica localizada, provocando um acréscimo da temperatura local. Supostamente estes sítios podem ser avaliados através da mensuração da temperatura. Objetivo: o objetivo geral deste estudo foi analisar a utilização da termografia como método de apoio ao diagnóstico de lesões musculares em atletas de rúgbi durante atividades de treino e jogo. Metodologia: participaram deste estudo, 21 atletas de rúgbi do sexo masculino com idades entre 19 e 31 anos, inscritos na Confederação Brasileira de Rúgbi, pertencentes à categoria adulta de um clube profissional de nível nacional, que executam treinamentos diários a mais de dois anos e que tenham participado por pelo menos 40 minutos de um treino ou partida oficial de rúgbi. Foram realizadas duas coletas de sangue para identificação da concentração sérica de CK, expressa em IU/L, sendo uma 48 h pós-treino e outra 48 h pós-jogo. Foi realizada a aquisição da imagem infravermelha dos atletas, sendo estes previamente orientados sobre os procedimentos a serem seguidos no dia dos exames. No momento da coleta, os atletas permaneceram vestidos apenas com a roupa íntima, em pé, por 30 minutos em repouso muscular em uma câmara de adaptação à temperatura, com temperatura e umidade controladas entre 22° e 23 °C e 45 e 50% respectivamente. Foram coletadas imagens do tronco (superior) e das coxas (inferior), nas incidências anterior e posterior. As imagens foram analisadas de forma sistemática e por inspeção. Resultados: a análise sistemática demonstra que não houve correlação entre a variação da CK e a variação de temperatura dos músculos analisados. A temperatura média das áreas selecionadas de todos os músculos foram maiores nos momentos de maior CK, porém, a variação de CK não apresentou correlação positiva significativa com a temperatura nestes mesmos momentos. Quando separado os sujeitos que apresentaram variação maior que 50% no nível sérico de CK entre os momentos de maior e menor concentração, os músculos peitoral esquerdo, reto femoral esquerdo e o semitendíneo esquerdo apresentaram as maiores diferenças com p-valor de 0,037, 0,057 e 0,045, respectivamente. O hemisfério corporal esquerdo apresentou uma maior diferença de temperatura quando comparado com o hemisfério corporal direito. A avaliação por inspeção mostrou que as regiões: superior anterior e inferior posterior apresentaram 13 atletas com aumento de temperatura maior que 0,6 °C coincidindo com um aumento do nível sérico de CK. A região superior posterior e a região inferior anterior apresentaram 11 atletas com variação de temperatura maior que 0,6 °C entre os momentos de maior e menor CK. Conclusões: pode-se concluir que a termografia pode e deve ser utilizada como método de apoio ao diagnóstico de lesão muscular em atletas, recomendando-se a utilização da análise por inspeção visual.
Introduction: Muscle lesions are very common and usually move away athletes from practicing sports, becoming also a nuisance to the clubs. Due to its characteristics, rugby is one of the sports where lesions on athletes happen very often. The muscle lesion presents a thermal variation in the affected area, causing a local increase of temperature. Supposedly these areas can be evaluated through the measurement of temperature. Objective: The general objective of this study was to analyze the use of thermography as a method of support on the diagnosis of muscle lesions in rugby athletes during training activities and games. Methodology: participating in this study were, 21 male rugby athletes, aged between 19 and 31 years old, registered with the Brazilian Rugby Confederation, belonging to the adult categories at a professional level of a national team, who perform daily training for over two years and who have participated for at least 40 minutes of training or of an official rugby match. Twice there were collections of blood samples so the serum CK could be identified, expressed in IU/L; one collection 48 hours after training and another 48 hours after a game. The infrared images of the athletes were obtained, these being previously instructed on the procedures to be followed on the day of the exam. On collection the athletes were dressed only with their underwear, standing up, for 30 minutes with muscle at rest in a chamber which adapts to the temperature, with temperature and humidity controlled between 22° and 23 °C and 45 and 50% respectively. Images were collected from the upper body (superior) and upper-legs (inferior), from anterior and posterior sides. The images were analyzed systematically and by inspection. Results: The systematic analysis revealed that there is no correlation between de CK variation and temperature variation in muscles analyzed. The average temperature in the selected areas of all muscles were higher when the CK was higher, however, the variation of CK did not show any significant positive correlation with the temperature in the same situations. When separating the participants who presented a variation higher than 50% on the serum CK level between moments of higher and lower concentration, the left upper body muscles, left rectus femoris and left semitendinosus presented the biggest differences with p-value of 0.037, 0.057 and 0.045, respectively. The left body hemisphere showed a bigger difference in temperature when compared with the right body hemisphere. The evaluation by inspection showed that the anterior superior and posterior inferior regions presented 13 athletes with increased temperature higher than 0.6 °C coinciding with an increase of the serum CK. The posterior superior and the anterior inferior presented 11 athletes with temperature variation higher than 0.6 °C between the moments of higher and lower CK. Conclusions: It is possible to conclude that thermography can and should be utilized as a supporting method to diagnose muscle lesion in athletes, recommending the use of the visual analysis by inspection.
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Lau, Wing Yin. "Pain assessment and possible mechanism of delayed onset muscle soreness". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2014. https://ro.ecu.edu.au/theses/1275.

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Muscle pain is felt during exercise or daily activities for several days after performing unaccustomed exercise, which is referred to as delayed onset muscle soreness (DOMS). Many people experience DOMS, but its underlying mechanisms are not fully understood. One of the challenges in the investigation of DOMS is its subjective nature, which makes the assessment ambiguous, thus establishing a standardised protocol is necessary. The present thesis scrutinised muscle pain assessments (Study 1, Study 2), developed a new assessment of muscle pain focusing on muscle fascia (Study 3), and investigated why DOMS is reduced after the second than the first bout of eccentric exercise (Study 4). From these studies, DOMS was thought to be more associated with connective tissue than muscle fibre damage and inflammation. In Study 1, the relationship between pain level assessed by a visual analogue scale (VAS) and pain sensitivity assessed by pressure pain threshold (PPT) was examined. Thirty-one healthy young men performed 10 sets of 6 maximal isokinetic eccentric contractions with their non-dominant arm. Before and 1 - 4 days after the exercise, muscle pain perceived upon palpation of the biceps brachii at three sites (5, 9, and 13 cm above the elbow crease) was assessed by VAS with a 100 mm line (0 = no pain, 100 = extremely painful), and PPT of the same sites was determined by an algometer. The VAS increased after exercise and peaked two days post-exercise, while the PPT decreased most at 1 day post-exercise and did not return to baseline for 4 days following exercise (P Muscle pain induced by elbow flexor eccentric exercise was investigated using different assessments in Study 2. Ten untrained men performed 10 sets of 6 maximal isokinetic eccentric contractions of the elbow flexors with one arm. Maximal voluntary isometric contraction torque (MVC), range of motion (ROM) and serum creatine kinase (CK) activity were measured before, immediately after, and 1 to 5 days after exercise as indirect markers of muscle damage. PPT of 50 sites over an exercised upper arm, VAS with a 100-mm line for pain level upon static pressure by a cuff and fingers, and palpation of the biceps brachii at three sites (3, 9, and 15 cm above the elbow crease) and different palpation methods (longitudinal, transverse and circular movements) on the mid-belly of biceps were assessed. Large decreases in MVC and ROM, and significant increases in serum CK activity indicated muscle damage. A significant difference (P In Study 3, changes in the electrical pain threshold (EPT) of the biceps brachii fascia, biceps brachii muscle and brachialis fascia following eccentric elbow flexor contractions, and the relationship between EPT and VAS or PPT were investigated. Ten healthy untrained men performed two eccentric exercise bouts (ECC1, ECC2) consisting of 10 sets of 6 maximal isokinetic eccentric contractions of the elbow flexors with the same arm separated by 4 weeks. Changes in MVC, ROM, VAS and PPT were smaller (P The purpose of Study 4 was to investigate the magnitude of muscle lengthening during the first and second bout of eccentric exercise bouts and whether the muscle length changes are associated with the magnitude of DOMS and changes in other indirect markers of muscle damages between bouts. Ten healthy untrained men performed two eccentric exercise bouts (ECC1, ECC2) consisting of 10 sets of 6 maximal isokinetic eccentric contractions of the elbow flexors using the same arm separated by 4 weeks. Changes in MVC, ROM, muscle thickness, ultrasound echo intensity, serum CK activity and muscle soreness (VAS) were smaller (P

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19

Roberts, Nathan T. "Musculoskeletal injuries in tactical law enforcement". Morgantown, W. Va. : [West Virginia University Libraries], 2010. http://hdl.handle.net/10450/11120.

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20

Contreras, Muñoz Paola. "Nuevas aproximaciones terapéuticas para la regeneración muscular basadas en el ejercicio físico, plasma rico en plaquetas (PRP) y glicosaminoglicanos en modelo de rata". Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/404884.

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Las lesiones del músculo esquelético son las lesiones más comunes en el ámbito deportivo (su frecuencia puede variar del 10-55%), siendo una preocupación importante en la medicina deportiva. Más del 90% de todas las lesiones deportivas son debidas traumas mecánicos, tales como contusiones musculares o lesiones por distensión, que a menudo conllevan la incapacidad del atleta para entrenar o competir durante varias semanas. Estas lesiones se caracterizan por sufrir rotura de sus fibras musculares, lámina basal y capilares cercanos; y se encuentran frecuentemente localizadas cerca de las uniones miotendinosas. El músculo esquelético tiene capacidad regenerativa en respuesta a una lesión, desencadenando un proceso de reparación altamente sincronizado que implica la activación de diversas respuestas celulares. Sin embargo, en lesiones severas, la fase de remodelación puede incluir un proceso de cicatrización (fibrosis) que perjudica la recuperación funcional del músculo y representa un importante riesgo de recurrencia. A pesar de que en los últimos años se han ampliado nuestros conocimientos sobre el proceso de regeneración del músculo esquelético, sus complejas vías de regulación todavía siguen siendo poco conocidas. Por todo ello, se plantea como necesario el desarrollo de nuevas aproximaciones terapéuticas para mejorar la regeneración muscular y evitar los problemas asociados a lesiones músculo-tendinosas; lo que podría generar un fuerte impacto social y económico en el campo de las patologías musculo-esqueléticas y lesiones musculares en el ámbito deportivo. En el presente proyecto se estableció con éxito un nuevo modelo de lesión quirúrgica muscular inducida en ratas, fácil de generar, altamente reproducible y capaz de imitar las lesiones más frecuentes del músculo esquelético observadas en la clínica deportiva humana. Así mismo, se demostró el efecto terapéutico de la administración de una dosis única de PRP mediante inyección intramuscular y, especialmente de la rehabilitación activa temprana (basada en el ejercicio), en la recuperación muscular, tanto a nivel histológico como en la recuperación de la fuerza del músculo esquelético lesionado mediante el uso del nuevo modelo experimental en ratas. No se observó un efecto sinérgico en la combinación de ambos tratamientos, lo que sugiere que el PRP no añade ningún efecto beneficioso al tratamiento basado en el ejercicio en el músculo esquelético lesionado. Estos resultados corroboran la falta de sinergia del PRP con respecto a la rehabilitación por actividad física demostrada en los últimos ECA realizados en clínica humana, donde los atletas fueron sometidos a protocolos de rehabilitación basados en el principio de movilización activa temprana tras la administración de una dosis única de PRP intramuscular. Por otro lado, se evaluaron también los efectos del tratamiento combinado de Condroitín Sulfato y Glucosamina, los cuales demostraron tener un efecto beneficioso en la regeneración del músculo esquelético lesionado en el modelo de lesión muscular en rata, tanto a nivel histológico como en la recuperación de la fuerza muscular, corroborando el papel clave de los componentes de la ECM durante el desarrollo muscular y la regeneración. A pesar de que se requieren más investigaciones, estos enfoques terapéuticos podrían abrir nuevas vías en el tratamiento de las lesiones del músculo esquelético humano y especialmente en el campo de la medicina deportiva.
Skeletal muscle injuries are the most common sports-related injuries in sports medicine. In this work, we have generated a new surgically-induced skeletal muscle injury in rats, by using a biopsy needle, which could be easily reproduced and highly mimics skeletal muscle lesions detected in human athletes. . By means of histology, immunofluorescence and MRI imaging, we corroborated that our model reproduced the necrosis, inflammation and regeneration processes observed in dystrophic mdx-mice, a model of spontaneous muscle injury, and realistically mimicked the muscle lesions observed in professional athletes. MRI imaging analysis demonstrated that our muscle injury model reproduces the grade I-II type lesions detected in professional soccer players, including edema around the central tendon and the typically high signal feather shape along muscle fibers. A significant reduction of 30 % in maximum tetanus force was also registered after 2 weeks of muscle injury. This new model represents an excellent approach to the study of the mechanisms of muscle injury and repair, and could open new avenues for developing innovative therapeutic approaches to skeletal muscle regeneration in sports medicine. We also evaluated the effects of an ultrasound-guided intramuscular PRP injection, administered 24 hours after injury, and/or post traumatic daily exercise training for 2 weeks on skeletal muscle healing in a recently established rat model of skeletal muscle injury. Intramuscular PRP injection and, especially, treadmill exercise improve histological outcome and force recovery of the injured skeletal muscle in a rat injury model that imitates sports-related muscle injuries in athletes. However, there was not a synergistic effect when both treatments were combined, suggesting that PRP does not add any beneficial effect to exercise-based therapy in the treatment of injured skeletal muscle. This could explain why PRP therapies have failed in randomized clinical trials where the athletes have adhered to post-injection rehabilitation protocols based on the principle of early, active mobilization. Moreover, we evaluated the beneficial effects of the combination of chondroitin sulfate (CS) and glucosamine (GLU) hydrochloride administration (both compounds used for the symptomatic osteoarthritis (OA) treatment) on muscle healing. The combined CS+GLU treatment improved muscle healing and force recovery of the injured skeletal muscle in rats, thus suggesting an important role of these products as potential new therapies for the treatment of muscle injuries in sports medicine.

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21

Schabort, Elske Jeanne. "The effect of the TGF-β isoforms on progenitor cell recruitment and differentiation into cardiac and skeletal muscle". Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/1295.

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Thesis (PhD (Physiology (Human and animal))-- University of Stellenbosch, 2007.
Definition: Stem cells are unspecialised cells with the capacity for long-term self-renewal and the ability to differentiate into multiple cell-lineages. The potential for the application of stem cells in clinical settings has had a profound effect on the future of regenerative medicine. However, to be of greater therapeutic use, selection of the most appropriate cell type, as well as optimisation of stem cell incorporation into the damaged tissue is required. In adult skeletal muscle, satellite cells are the primary stem cell population which mediate postnatal muscle growth. Following injury or in diseased conditions, these cells are activated and recruited for new muscle formation. In contrast, the potential of resident adult stem cell incorporation into the myocardium has been challenged and the response of cardiac tissue, especially to ischaemic injury, is scar formation. Following muscle damage, various growth factors and cytokines are released in the afflicted area which influences the recruitment and incorporation of stem cells into the injured tissue. Transforming Growth Factor-β (TGF-β) is a member of the TGF-β-superfamily of cytokines and has at least three isoforms, TGF-β1, -β2, and -β3, which play essential roles in the regulation of cell growth and regeneration following activation and stimulation of receptor-signalling pathways. By improving the understanding of how TGF-β affects these processes, it is possible to gain insight into how the intercellular environment can be manipulated to improve stem cell-mediated repair following muscle injury. Therefore, the main aims of this thesis were to determine the effect of the three TGF-β isoforms on proliferation, differentiation, migration and fusion of muscle progenitor cells (skeletal and cardiac) and relate this to possible improved mechanisms for muscle repair. The effect of short- and long-term treatment with all three TGF-β isoforms were investigated on muscle progenitor cell proliferation and differentiation using the C2C12 skeletal muscle satellite and P19 multipotent embryonal carcinoma cell-lineages as in vitro model systems. Cells were treated with 5 ng/mℓ TGF-β isoforms unless where stated otherwise. In C2C12 cells, proliferating cell nuclear antigen (PCNA) expression and localisation were analysed, and together with total nuclear counts, used to assess the effect of TGF-β on myoblast proliferation (Chapter 5). The myogenic regulatory factors MyoD and myogenin, and structural protein myosin heavy chain (MHC) were used as protein markers to assess early and terminal differentiation, respectively. To establish possible mechanisms by which TGF-β isoforms regulate differentiation, further analysis included determination of MyoD localisation and the rate of MyoD degradation in C2C12 cells. To assess the effect of TGF-β isoforms on P19 cell differentiation, protein expression levels of connexin-43 and MHC were analysed, together with the determination of embryoid body numbers in differentiating P19 cells (Chapter 6). Furthermore, assays were developed to analyse the effect of TGF-β isoforms on both C2C12 and P19 cell migration (Chapter 7), as well as fusion of C2C12 cells (Chapter 8). Whereas all three isoforms of TGF-β significantly increased proliferation of C2C12 cells, differentiation results, however, indicated that especially following long-term incubation, TGF-β isoforms delayed both early and terminal differentiation of C2C12 cells into myotubes. Similarly, myocyte migration and fusion were also negatively regulated following TGF-β treatment. In the P19 cell-lineage, results demonstrated that isoform-specific treatment with TGF-β1 could potentially enhance differentiation. Further research is however required in this area, especially since migration was greatly reduced in these cells. Taken together, results demonstrated variable effects following TGF-β treatment depending on the cell type and the duration of TGF-β application. Circulating and/or treatment concentrations of this growth factor could therefore be manipulated depending on the area of injury to improve regenerative processes. Alternatively, when selecting appropriate stem or progenitor cells for therapeutic application, the effect of the immediate environment and subsequent interaction between the two should be taken into consideration for optimal beneficial results.

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22

Larsson, Helena. "Premature discharge from military service : risk factors and preventive interventions /". Stockholm : Karolinska institutet, 2009. http://diss.kib.ki.se/2009/978-91-7409-435-0/thesis.pdf.

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23

Elliott, Andrew Brent. "Risk assessment and the effects of overhead work - an automotive industry example". Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1005211.

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The focus of this investigation was an analysis of the work demands being placed on South African automotive industry workers as there is a recognised problem with regard to the prevalence of musculoskeletal disorders (MSDs). Preliminary work was conducted to highlight the dominant risks and areas which elicited higher numbers of MSDs within the chosen automotive plant. An area of concern was highlighted through medical record analysis and the use of risk assessment tools, thereby prioritising the need for ergonomic intervention. In particular, the effects of varying restricted and overhead work heights on the biomechanical, physiological and psychophysical responses of an individual were investigated. Twenty-eight subjects were required to complete sixteen conditions. The conditions consisted of the adoption of restricted and upright overhead static postures, with half requiring the holding of four kilograms of weight in the hands and the remaining eight conditions having no weight. Testing was carried out using an electromyography unit, ergospirometer and a perceptual Body Discomfort Map and Scale. This involved a habituation and testing session. The results of the testing revealed the biomechanical and physiological responses were dependant on the change in height. Body discomfort was also shown to be variable over the changing height conditions. This indicates that there is a significant effect of height on an individual’s responses during overhead work. The extreme restricted (-200mm and -100mm) and upright (+300mm and +400mm) overhead conditions within this study were limiting, as they elicited the highest muscle activation, physiological responses and body discomfort ratings. Positions that are preferable to adopt, which were identified from the results in this study, indicate conditions closer to head height (0mm and +100mm) were favourable. The results therefore illustrate how awkward working postures during work are likely to elicit higher demands from an individual, which could lead to an increased risk for the development of a musculoskeletal disorder. The added factor of weight elicited significant results over all variables, excluding a respiratory The focus of this investigation was an analysis of the work demands being placed on South African automotive industry workers as there is a recognised problem with regard to the prevalence of musculoskeletal disorders (MSDs). Preliminary work was conducted to highlight the dominant risks and areas which elicited higher numbers of MSDs within the chosen automotive plant. An area of concern was highlighted through medical record analysis and the use of risk assessment tools, thereby prioritising the need for ergonomic intervention. In particular, the effects of varying restricted and overhead work heights on the biomechanical, physiological and psychophysical responses of an individual were investigated. Twenty-eight subjects were required to complete sixteen conditions. The conditions consisted of the adoption of restricted and upright overhead static postures, with half requiring the holding of four kilograms of weight in the hands and the remaining eight conditions having no weight. Testing was carried out using an electromyography unit, ergospirometer and a perceptual Body Discomfort Map and Scale. This involved a habituation and testing session. The results of the testing revealed the biomechanical and physiological responses were dependant on the change in height. Body discomfort was also shown to be variable over the changing height conditions. This indicates that there is a significant effect of height on an individual’s responses during overhead work. The extreme restricted (-200mm and -100mm) and upright (+300mm and +400mm) overhead conditions within this study were limiting, as they elicited the highest muscle activation, physiological responses and body discomfort ratings. Positions that are preferable to adopt, which were identified from the results in this study, indicate conditions closer to head height (0mm and +100mm) were favourable. The results therefore illustrate how awkward working postures during work are likely to elicit higher demands from an individual, which could lead to an increased risk for the development of a musculoskeletal disorder. The added factor of weight elicited significant results over all variables, excluding a respiratory individual.

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24

Lam, Yuk-ling. "Patterns of musculoskeletal injuries in collegiate dancers /". Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B2342543x.

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25

Prenzler, Elizabeth A. "Musculoskeletal adaptation to dance". Thesis, Queensland University of Technology, 1998. https://eprints.qut.edu.au/36748/1/36748_Prenzler_1998.pdf.

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Training can facilitate adaptive changes in the human body in response to activity, and these changes are evident in dancers. Unique manoeuvres inherent in the training programmes and performance of dancers have a significant influence on adaptive responses of the musculo-skeletal system. These set manoeuvres must be executed to be visually correct and often involve extreme ranges of movement, along with highly repetitive moves and frequent jumping. As dancers often begin training at an early age, physiological changes may take place as their bodies adapt to the positions and loads experienced. Additional factors that may influence adaptation are nutritional deficiencies, menstrual abnormalities, floor surfaces, inadequate footwear and hours of practice. The process of adaptation affects both the skeletal and muscular systems of the body and both positive and negative consequences are evident. Negative effects may be expressed by high injury rates, pertaining mainly to the lower limb and often chronic in nature. A significant factor in the cause of injury relates to the inability to effectively match training levels and intensities with positive adaptation. Bone mineral density (BMD) is one measure that can be taken to examine the adaptive response of bone. Following training, BMD has been found to increase at specific sites in response to loading at those sites. However, if the loads or frequency of loads are too great, failure may occur which may ultimateiy lead to stress fractures. Muscular adaptation to training may be evident by increases in muscular strength and the presence of muscle imbalance, although a precise definition of what constitutes an imbalance is unclear. Studies claim that symmetry in terms of strength should exist between muscles on opposite sides of the body, or that a specific ratio is found between the agonisUantagonist muscle groups of the same extremity. A discrepancy of more than 10% from expected values has been classified as an imbalance, potentially causing injury, and muscle imbalances have frequently been linked with dancing injuries. While many studies have investigated imbalance and injury, the relationship between them is still unclear and few studies have targeted specific muscle groups in the area of dance. It is necessary to prospectively examine this relationship and to more closely monitor training intensities and subsequent changes in the musculo-skeletal system. The purpose of this study was to investigate prospectively the relationship between factors commonly associated with injuries and the injury profiles of female dancers. The specific aims were to determine the anthropometry, skeletal status, muscular strength and flexibility characteristics of this group of dancers; to investigate the nature of the training program with respect to duration, intensity and frequency components; and to investigate the relationship between these factors and injury throughout a season of dancing. Twenty female dance students from the Queensland University of Technology dance program and five female dance students from the Brisbane Dance Centre participated in the study. Over a 10-month period, five measures were taken at the beginning of the university semester. Muscie strength was measured using a Kin-Com isokinetic dynamometer including hip flexors/extensors, hip abductors/adductors, hip external/internal rotators, knee fiexors/extensors, ankle invertors/evertors and ankie plantar/dorsiflexors. These measures were also used to determine muscle strength ratio's. Passive ranges of movement of the above actions were measured using a Leighton flexometer. The Lunar densitometer was used to measure bone mineral density of the proximal femur and lumbar spine. Anthropometric measures were used to establish body composition and a submaximal fitness test was carried out at each of the test periods. Continual monitoring of activity levels and injuries occurred throughout the 10 month period. Training intensity was established by analysis of dance classes, activity diaries and force plate measurements. The training hours of dancers were not significantly different between injured and non-injured dancers. It was noted however, that there was a discrepancy between the number of hours recorded and the actual number of active hours completed in the dancers training history, due to the nature of the dance classes. No skeletal injuries were recorded, therefore a comparison with BMD measures could not be made, however the values from the dancers from this study were higher than previous dance studies. Muscular characteristics in terms of strength and flexibility did show evidence of adaptation at certain joints compared to normal values, however they were different again to professional dancers. While a number of characteristics showed significant differences between injured and non-injured groups, these were viewed with caution due to the exploratory nature of the study. They did reveal however, that further investigation, particularly around the ankle joint and hip joint is warranted.

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26

Sweitzer, Michael. "Injury surveillance of amateur motocross associated injuries over a six race series concussions versus musculoskeletal injuries /". Morgantown, W. Va. : [West Virginia University Libraries], 2009. http://hdl.handle.net/10450/10225.

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Thesis (M.S.)--West Virginia University, 2009.
Title from document title page. Document formatted into pages; contains vii, 107 p. : ill. (some col.). Includes abstract. Includes bibliographical references. WVU users: Also available in print for a fee.

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27

Margand, Paul Marcus Buchanan. "Ultrastructural changes in electrically damaged x-enopus laevis sciatic nerve". Scholarly Commons, 1991. https://scholarlycommons.pacific.edu/uop_etds/2217.

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Electrical injury is known to alter the normal physiological function of nerves. In most cases, the change in function is only minor, but in severe instances the physiological function may be lost entirely. The changes in function involve the ability of the nerve to transmit an impulse, which is a function of the nerve's ability to create and maintain an electrical gradient across its membrane. When the nerve is exposed to an electrical current, the ability to maintain an electrical gradient across the membrane is reduced or lost. This change may be transient or permanent. The changes in the gradient hinder the nerve from propagating the impulse, which is the means of information transfer to and from the CNS (central nervous system). Due to the manner in which human victims are typically exposed to an electric shock, the peripheral axons usually display the greatest change in physiological function.

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28

Corletto, Federico. "Role of the HIF system in brain injury". Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609260.

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29

Moore, Leah Kathryn. "Neuronal viability and biochemical alterations after mechanical stretch injury: ban in vitro model of traumatic brain injury-induced neourodegeneration". Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/5362.

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30

Leung, Ka-kit Gilberto, e 梁嘉傑. "Trauma system and traumatic brain injury in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42182487.

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31

Dorsch, Angel M. "Design of a rodent dynamometer". Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3317.

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Thesis (M.S.)--West Virginia University, 2004.
Title from document title page. Document formatted into pages; contains x, 122 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 78-83).

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32

Lang, Dianne L. "Subtyping closed head injury patients using the Dean-Woodcock neuropsychological assessment system". Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1137610.

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The present study attempts to further define the neuropsychological characteristics associated with mild, moderate, and severe closed head injuries (CHI). The Dean-Woodcock Neuropsychological Assessment System (D-WNAS), a new neuropsychological battery, was administered to 119 CHI patients. The scores of the cognitive portion of the D-WNAS were then analyzed via cluster analysis in an attempt to further delineate neuropsychological impairment into more specific classifications occurring within types of brain trauma.Results suggested that the cognitive portion of the D-WNAS was effective in separating 4 subtypes within CHI, which are best interpreted as "profiles" or characteristics associated with "levels" of impairment. These levels of impairment were characterized by distinctly different subtest profiles, and were labeled as mild/high functioning, mild, moderate, and severe. The highest performing group, mild/high functioning, showed no neuropsychological deficits. The most severely impaired group was characterized by many deficits in short-term memory, visual stimuli, new learning, processing speed, visual-spatial abilities, abstract reasoning, attention/concentration, and remote memory tasks. A multivariate analysis showed that educational level was significant in differentiating between the subtypes and suggested that, depending on the severity of injury, educational level might also protect individuals from obtaining a poorer prognosis.From this investigation, the cognitive portion of the D-WNAS appears to offer valuable utility in identifying CHI patients and in further classifying their varied neuropsychological characteristics. Implications for diagnosing and differentiating between different levels or profiles of CHI was discussed.
Department of Educational Psychology

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33

Schwellnus, Martin. "Physical activity and overuse injuries : factors associated with the aetiology and management of overuse injuries that occur during physical activity with specific reference to bone stress injuries and the iliotibial band friction syndrome". Doctoral thesis, University of Cape Town, 1992. http://hdl.handle.net/11427/26289.

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34

Chitre, Yougandh. "The development and characterization of a system to impart a mechanical deformation to a culture of neural-like cells to emulate in vivo traumatic brain injury". Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/17826.

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35

Harp, Phillip Allan. "System to compress while electrically stimulating hippocampal brain slices (SCWESH) : design, development, and electromechanical validation". Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/16828.

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36

Spielholz, Peregrin. "A comparison of upper extremity physical risk factor measurement methods /". Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/8468.

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37

Bastos, Lopes Alves João Nuno. "Strategies to block inhibition and restore plasticity in the central nervous system after injury". Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708968.

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38

Reed, Suzanne Rene. "Epidemiology of joint injuries in thoroughbred racehorses in training". Thesis, Royal Veterinary College (University of London), 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559071.

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39

Bell, Heather C., e University of Lethbridge Faculty of Arts and Science. "Playful feedback and the developing brain". Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2008, 2008. http://hdl.handle.net/10133/747.

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The prefrontal cortex (PFC) has long been thought to be the seat of social behaviours in mammals. Lesions of the orbitofrontal cortex (OFC), a subregion of the PFC, are known to cause social deficits in humans. Interestingly, social deficits are also seen in rats with OFC lesions. Rats that are deprived of peer play during development exhibit behaviour similar to OFC-ablated animals. Another subregion of the PFC, the medial prefrontal cortex (mPFC) is interconnected with the OFC. The mPFC and OFC have been shown to be reciprocally responsive to a variety of inuences, in terms of dendritic morphology. It was hypothesized that social experiences are necessary for the proper development of the OFC, and that, because of the interconnectivity, the mPFC would also be sensitive to social experience. The social condition in which juvenile rats were raised was manipulated, and the OFC and mPFC were shown to be differentially responsive to specific aspects of social experience. It was already known that OFC lesions produce specific social deficits, but the contribution of the mPFC to the production of social behaviour was unknown. To investigate the contribution of the mPFC to the performance of social behaviour, animals were given mPFC lesions, and their social play behaviour was quantified. mPFC-ablated animals had altered play patterns that were distinct from those seen in the OFC-ablated animals. It was concluded that the OFC and mPFC are differentially responsive to social stimuli during development, and that the OFC and mPFC make discrete contributions to the production of social behaviour. The results were interpreted in an evolutionary context.
x, 93 leaves : ill. ; 29 cm.

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40

Yuan, Qiuju, e 袁秋菊. "The plasticity of hypothalamic magnocellular system following axonal damage by hypophysectomy in developing and adult rats". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B30301117.

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41

Hobbs, Catherine E., e n/a. "Perinatal hypoxia-ischaemia : neuroprotective strategies". University of Otago. Department of Anatomy & Structural Biology, 2005. http://adt.otago.ac.nz./public/adt-NZDU20070221.145910.

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Perinatal hypoxia-ischaemia is a major cause of disability, including cerebral palsy, yet a neuroprotectant which fully protects the brain remains elusive. Following a hypoxic-ischaemic insult, striatal medium-spiny neurons and hippocampal CA1 neurons are vulnerable to a complex cascade of neurotoxic events. This cascade includes energy failure, a massive release of glutamate, the formation of free radicals and caspase activation. The overall aim of this thesis was to assess the efficacy of three potential neuroprotective strategies that target this cascade from different directions. Short-term, and where appropriate, long-term, neuroprotection was investigated. The first treatment strategy aimed to suppress the generation of free radicals through treatment with the potent free radical spin trap, N-tertbutyl-(2-sulphophenyl)-nitrone (S-PBN). The second compound tested was the caspase-3 inhibitor, minocycline. Finally, the third treatment strategy combined a series of S-PBN injections with 6 hours of moderate hypothermia immediately after hypoxia-ischaemia. Hypothermia is suggested to slow the rate of the neurotoxic cascade, thus potentially allowing other neuroprotective agents greater efficacy. Using an adaptation of the Rice et al. (1981) model, hypoxia-ischaemia was induced on postnatal day (PN) 8 in the right cerebral hemisphere. For the short-term studies, the rats were perfused at 14 days-of-age. The brains were dissected out and embedded in Technovit. Forty [mu]m serial sections were cut through the right striatum and hippocampus. The total number of medium-spiny neurons in the striatum and where appropriate, the total number of neurons in the hippocampal CA1 pyramidal layer, were stereologically determined using the optical disector/Cavalieri method. For the long-term study, fine motor control was assessed in half of the animals through the staircase test from 9-11 weeks-of-age. Neuroprotection was assessed in the remaining animals. All animals were sacrificed at 12 weeks-of-age. The total number of striatal medium-spiny neurons was stereologically determined in the non-behavioural animals as described above. A series of seven injections of S-PBN (100mg/kg) did not offer statistically significant neuroprotection to the striatum at one week after perinatal hypoxia-ischaemia. Similarly, a single injection of minocycline (45mg/kg) immediately after the insult did not offer significant neuroprotection to the striatum nor the CA1 region of the hippocampus at this early time-point. In contrast, when the series of S-PBN injections was combined with 6 hours of moderate hypothermia post-hypoxia-ischaemia, sterelogical analysis revealed significant neuroprotection of the striatal medium-spiny neurons to normal levels at one week after the injury. No significant neuroprotection was seen in the CA1 region of the same animals. To assess whether this impressive striatal neuroprotection was long-lasting and whether it represented functional rescue, the final experiment in this thesis investigated rat pups at 12 weeks-of-age after exposure to hypoxia-ischaemia at PN8. Treatment with S-PBN/hypothermia offered persistent neuroprotection of striatal medium-spiny neurons and preservation of fine motor skills compared to diluent-normothermia-treated controls. The long-term behavioural outcomes were compared with normal, uninjured controls and the total number of medium-spiny neurons was compared with normal numbers from the literature. These comparisons revealed that the histological and functional integrity of the striatum was rescued to normal levels. This is the first study to identify a treatment strategy that offers complete and long-lasting preservation of striatal neuronal numbers, by accurate and unbiased stereological methods, paired with persistent preservation of fine motor control following perinatal hypoxia-ischaemia.

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42

Millner, Mary Angela. "Modulation of CSPG sulfation patterns through siRNA silencing of sulfotransferase expression to promote CNS regeneration". Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24647.

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43

Niu, Chenchen, e 牛晨晨. "The neuroprotective signaling mechanisms of telomerase via the induction by brain-derived neurotrophic factor (BDNF) in nervoussystem injury". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45152883.

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44

Pulido, Kelly Cristina Strazzieri. "Adaptação cultural e validação do instrumento \"Star Skin Tear Classification System\", para a língua portuguesa no Brasil". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/7/7139/tde-23122010-103305/.

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O objetivo do estudo foi realizar a adaptação cultural do STAR Skin Tear Classification System, para a língua portuguesa no Brasil e testar a validade de conteúdo e a confiabilidade inter-observadores da versão adaptada. O estudo é do tipo metodológico com abordagem quantitativa. A adaptação cultural foi desenvolvida em três fases: tradução, avaliação por comitê de juízes e retro-tradução. Foram testadas duas propriedades de medida: validade de conteúdo e confiabilidade inter-observadores. Para as análises estatísticas foi utilizado o índice kappa ponderado. A versão adaptada para o português obteve um nível regular de concordância (kw = 0,286), embora estatisticamente significativo (p = 0,000), quando de sua aplicação por enfermeiros em fotografias de lesão por fricção. Quando de sua aplicação na prática clínica, a versão adaptada em português obteve um nível moderado e estatisticamente significativo de concordância (kw = 0,596; p < 0,001). O estudo sobre o processo de adaptação cultural e validação das propriedades de medida do STAR Skin Tear Classification System possibilitou atestar a validade de conteúdo e a confiabilidade inter-observadores da versão adaptada para uso na língua portuguesa do Brasil
This study aims to perform a cultural adaptation of the STAR Skin Tear Classification System, to the Portuguese language spoken in Brazil and to test its contents validity and the reliability in the translated version. This is a methodological type of study with a quantitative approach. The cultural adaptation was developed in three stages: translation, evaluation by a judges committee and back translation. Two measures were tested: validity and reliability. The statistical analysis used the weighted kappa index. The adapted version had a regular concordance level (kw = 0,286), although statistically significant (p < 0,000) when tested by nurses in skin tears photographs. When tested in clinical practice, the adapted version achieved a moderate and statistically significant concordance level (kw = 0,596; p < 0,001). The study about the cultural adaptation process and validation of the measurements properties of the STAR Skin Tear Classification System confirmed the adapted Brazilian Portuguese version content validity and reliability

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Jin, Ying, e 金瑩. "Neuronal survival and axonal regeneration of the lateral vestibular nucleus in rats after spinal cord injury". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31237113.

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46

Hu, Ying. "Optic nerve regeneration in adult rat". University of Western Australia. School of Anatomy and Human Biology, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0080.

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[Truncated abstract] There is limited intrinsic potential for repair in the adult human central nervous system (CNS). Dysfunction resulting from CNS injury is persistent and requires prolonged medical treatment and rehabilitation. The retina and optic nerve are CNSderived, and adult retinal ganglion cells (RGCs) and their axons are often used as a model in which to study the mechanisms associated with injury, neuroprotection and regeneration. In this study I investigated the effects of a variety of strategies on promoting RGC survival and axonal regeneration after optic nerve injury, including the use of reconstructed chimeric peripheral nerve (PN) grafts, gene therapy, and intraocular application of pharmacological agents and other factors . . . C3 transferase is an enzyme derived from Clostridium botulinum that inactivates Rho GTPase. Because SC myelin contains MAG and PN also contains CSPGs, I tested the effects of intraocular injection of a modified form of C3 (C3-11), provided by Dr Lisa McKerracher (CONFIDENTIAL data, under IP agreement with Bioaxone Therapeutic, Montreal) on RGC axonal regeneration into PN autografts. My results showed that there was significantly more RGC survival and axonal regeneration in PN autografts after repeated intraocular injection of C3. I also tested whether intraocular injections of CPT-cAMP and/or CNTF can act in concert with the C3 to further increase RGC survival and/or regeneration. Results showed that the effect of C3 and CPT-cAMP plus CNTF were synergistic and partially additive. The use of combination therapies therefore offers the best hope for robust and substantial regeneration. The overall results from my PhD project will help determine how best to reconstruct nerve pathways and use pharmacological interventions in the clinical treatment of CNS injury, hopefully leading to improved functional outcomes after neurotrauma.

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Estep, Christina Renee. "Modeling of the human head/neck system using rigid body dynamics". Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-10062009-020148/.

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易亮華 e Leung-wah Yick. "Promotion of neuronal survival and axonal regeneration in Clarke's nucleus after spinal cord injury in adult rats". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31239651.

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Shi, Ri Yi. "Neuronal Survival After Dendrite Amputation: Investigation of Injury Current Blockage". Thesis, University of North Texas, 1988. https://digital.library.unt.edu/ark:/67531/metadc501278/.

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After dendrite transection, two primary injury current pathways may acount for cell death: (1) the lesion current at the site of injury and (2) the voltage sensitive calcium channels along the dendrite. Lesions were made with a laser microbeam in mouse spinal monolayer cell cultures. Polylysine was tried as a positively charged "molecular bandage" to block the lesion current. The calcium channel blockers, verapamil and nifedipine, were used to reduce the calcium channel current. Control toxicity curves were obtained for all three compounds. The results show that neither verapamil, nifedipine, nor polylysine (MW: 3,300) protect nerve cells after dendrite amputation 100 ptm from the soma. The data also indicate that these compounds do not slow the process of cell death after such physical trauma.

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袁秋菊 e Qiuju Yuan. "Effects of neurotrophic factors on motoneuron survival following axonal injury in developing rats". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B42128705.

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Tesi sul tema "Musculoskeletal system – Wounds and injuries"

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