The focus of the present study was on the investigation of the effects of an intervention strategy on an industrial task in situ and a simulation of the same task within a laboratory setting. The task of offloading crates from a truck at a local business was simulated in a laboratory setting for rigorous analysis. The effect of an ergonomically sound intervention on selected physical, physiological and perceptual variables was evaluated in a test - retest experimental set-up using 28 young, healthy male students. Each of the two experimental conditions lasted for 16 minutes. In the pre-intervention task subjects were required to transfer the crates from one point to another by sliding them along the floor. During the execution of the post-intervention task responses to reductions in the stacking height and modifications of the working method were evaluated. Results obtained for spinal kinematics during the simulated industrial task indicated a high biomechanical risk, due to large ranges of motion, high velocities and accelerations in the sagittal and transverse planes. The heavy workload of the task was also evident in elevated physiological responses (HR, RF, VT, VE, VO2, RQ, EE) and perceptual ratings (RPE, Body Discomfort). Assessment of the intervention strategy revealed that the ‘high risk’ industrial task was reduced to ‘moderate acceptable’, with measurements of spinal kinematics, physiological and perceptual variables being significantly reduced. An in situ re-assessment of the workers’ responses to the intervention also elicited reductions in heart rates and perceptual ratings compared to the original task.

Work-related musculoskeletal disorders (WMDs) are a major public health problem in terms of the considerable amount of disability, impairment, and associated economic cost. Among these disorders, the occurrence of WMD symptoms of the neck is prevalent and has been associated with significant disability, long periods of sick leave and loss of productivity in occupational settings. Risk factors for WMDs are multifactorial, and studies have typically focused on ergonomic factors. Psychosocial factors in the work environment have been recently considered; however, findings across these studies have not been consistent. Despite the evidence associated with ergonomic factors on the occurrence of WMDs, widespread prevention and treatment efforts have not been successfully implemented. Psychosocial factors such as high psychological demands, low decision latitude and low social support may play a role in WMD occurrence. The demand-control-support model has been widely used to predict job strain. Particularly for disorders of the neck, job strain seems to play a strong role in their occurrence. The psychosocial work environment and WMDs are listed as research priorities of the National Occupational Research Agenda developed by the National Institute for Occupational Safety and Health. This cross-sectional study looked at job strain and neck symptoms, while controlling for confounders. This project was carried out on a group of semiconductor manufacturing workers. The prevalence of neck symptoms was measured by a self-administered questionnaire. A Chinese version of the Job Content Questionnaire was included to assess psychosocial factors and to test the demand-control-support model. An observational checklist was developed and used to assess ergonomic exposures on individual workers' jobs. The participation rate was 86.5%. The final sample of semiconductor workers consisted of 373 female participants. Their mean age was 28.4 years ranging from 18 to 41 years. The mean length of employment was 4.3 years. The prevalence of symptoms of neck disorders in the semiconductor manufacturing population was 23.9%. It was concluded that the prevalence rates of neck symptoms of WMDs in this study were high, especially given the very conservative outcome definition that was used. The study findings partially supported the job strain model, showing an increase in prevalence of neck symptoms with psychological and physical job demands; however, association with decision latitude and social support were not supported. Further studies with more comprehensive measurements of work-related psychosocial factors are implicated and effective prevention strategies for neck symptoms of WMDs are suggested.

The purpose of this study was to investigate problem areas of organists' performance as indicated by common experiences of pain. The research problems were to determine the specific areas of the body that were affected by pain, to determine the perceived level of that pain on a scale indicative of its severity, and to explore the relationship between demographic and performance-related factors within the population and specific area of reported pain. An examination of the demographic, performance-related, and pain data, as well as subject comments, indicated possible relationships of the pain experience to other factors. Organists attributed their pain to instrument characteristics, such as keyboard action, music rack height, bench design, and pedalboard shape. Pain was also associated with the time spent playing the organ, playing literature which required large reaches and rapid passage work, such as french toccatas, or playing with incorrect posture. To explore these relationships to spinal and upper extremity pain, further research is indicated.

Includes bibliographical references (leaves 292-352) Determines the role of matrix metalloproteinases, MMP-2 and MMP-9 in reperfusion injury following skeletal muscle ischaemia; and, whether inhibition of MMPs by doxycycline protects against tissue damage.

Includes bibliographical references (leaves 292-352) / xvi, 352 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Determines the role of matrix metalloproteinases, MMP-2 and MMP-9 in reperfusion injury following skeletal muscle ischaemia; and, whether inhibition of MMPs by doxycycline protects against tissue damage. / Thesis (M.D.)--University of Adelaide, Dept. of Surgery, 2002

Includes bibliographical references (leaves 292-352) / xvi, 352 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Determines the role of matrix metalloproteinases, MMP-2 and MMP-9 in reperfusion injury following skeletal muscle ischaemia; and, whether inhibition of MMPs by doxycycline protects against tissue damage. / Thesis (M.D.)--University of Adelaide, Dept. of Surgery, 2002

Submitted in fulfillment of the requirements for the Degree of Master of Health Sciences in Nursing, Durban University of Technology. Durban. South Africa, 2017. / Introduction Musculoskeletal disorders (MSDs) are classified as occupational disease. They are described as disorders that affect the musculoskeletal system, and affect the health, productivity and careers of the working population. Dental technicians are at risk of MSDs as much as other members of the dental professionals as a result of their daily activities which involves manual work or they could be labour intensive. The risk factors for MSDs among dental professionals are multifactorial. Problem Statement There are currently no established statistics on the prevalence and risk of musculoskeletal disorders among dental technicians in South Africa. Purpose The purpose of the study was to determine the prevalence and risk of MSDs among dental technicians in South Africa. Research Method A quantitative research approach using a cross sectional correlational survey design was adopted for this study. Using a purposive sampling, the data base of all the dental technicians was obtained from the South African Dental Technician Council (SADTC) and those with valid e-mail addresses and telephone numbers were invited to participate in the study. A modified Nordic musculoskeletal questionnaire was used to collect data, 79 technicians responded with only 72 valid questionnaires available for analysis. Results The twelve month prevalence rate of MSDs among dental technicians in South Africa is 90%. MSDs was reported in all body parts and across all ages and genders. The prevalence for neck, hand/wrist, upper back and low back pain were the highest, having the same prevalence rate of 68.1%. The risk factors for MSDs in at least one body part that were identified in this study are age, prolonged standing and vibration. There was no significant relationship between gender, alcohol intake, smoking, having children and MSDs in any body part. However, a relationship exists between age and MSDs in the wrist/hand, standing and elbow pain, vibration and lower back symptoms. Conclusion The study showed that the prevalence of musculoskeletal disorder is high (90%) among dental technicians in South Africa. The prevalence of MSD is not age or gender related. However, some affected body parts were directly linked to age, standing and vibration. More research needs to be done on the ergonomics and workplace in order to address the high incidence of MSDs. / M

Ergonomics aims to improve worker health and enhance productivity and quality. Knowledge and practical evidence of this relationship would be instrumental for optimising organisational performance particularly in industrially developing countries where the discipline is still in its developmental stages. Therefore this thesis set out to analyse the relationship between ergonomics deficiencies and performance. A survey was first conducted to establish the severity of quality problems in the South African manufacturing industry and to determine if these were related to Ergonomic deficiencies. The results indicated that quality problems continue to plague industry, a challenge associated with huge cost implications. Furthermore organisations were not cognisant of the fact that ergonomics deficiencies such as poor workstation design and awkward or constrained working postures are a major contributing factor to poor quality and performance decrements. This demonstrates that much is yet to be done in raising awareness about the benefits of ergonomics in South Africa and other industrially developing countries. However, for this to be effective, tangible evidence of these purported benefits is required. In lieu of this, a laboratory study was then conducted to establish the relationship between awkward working postures and the performance of precision tasks. Acknowledging that the task and the worker are interrelated elements, the impact of precision task demands on the postural strain experienced by the human was also investigated. A high and low precision task quantified positional precision while a force task (combination of pushing and pulling) was utilised to assess the ability to maintain a precise force over time. These three tasks were performed in eight different postures; namely seated, standing, stooping 300 and 600, working overhead, lying supine, and twisting to either side. A combination of the tasks and postures resulted in 24 experimental conditions that were tested on forty eight healthy male and female participants. The performance related dependent variables were movement time, deviation from the centre of the target, and the trend/slope followed by the force exerted. Muscle activity of eight arm, shoulder and back muscles, iii supplemented with heart rate and local ratings of perceived exertion, were utilised to quantify the impact of the tasks and the postures on the individual. The results revealed that awkward working postures do in fact influence performance outcomes. In this regard, awkward working postures (such as overhead work and lying supine and stooping) were evidenced to significantly affect movement time, deviations from the target and the ability to maintain a constant force over time. These variables have a direct relationship with organisational priorities such as productivity and quality. Furthermore, the results indicated that high precision demands augment postural strain elicited through high muscle activity responses and may have negative implications for the precipitation of musculoskeletal disorders. Essentially, the work done on this thesis reflected the complex nature of ergonomics by drawing on both macro and micro-ergonomics approaches. In so doing, challenges perceived to be relevant to industry as reported by organisations formed the foundation for further laboratory studies. Therefore, more collaborative research and knowledge transfer between industry and ergonomics researchers is a necessity particularly in industrially developing countries where ergonomics is still in its developmental stages.

Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: Tumour necrosis factor alpha (TNFα) is a pleiotropic cytokine and has a wide variety of dose dependent cellular effects ranging from cell growth and differentiation, to inducing apoptosis. It has long been implicated in muscle and non-muscle inflammatory disorders, such as muscle wasting in chronic disease states, and rheumatoid arthritis. However, a physiological role for TNFα in muscle regeneration has been proposed as elevated levels of the cytokine are present when muscle regeneration processes are initiated: TNFα is secreted by infiltrating inflammatory cells, and by injured muscle fibres. Adult skeletal muscle contains a population of resident stem cell-like cells called satellite cells, which become activated, proliferate and differentiate following muscle injury to bring about repair of damaged muscle. Much research on the effects of TNFα on satellite cell differentiation has been conducted in recent years. It is however difficult to get a complete characterisation of the cytokine’s action as all models used slightly differ. We aimed therefore at providing comprehensive assessment of the effects of increasing doses of chronically supplemented TNFα on differentiating C2C12 cells. Cells were allowed to differentiate with or without TNFα supplementation for 7 days. Differentiation was induced at day 0. The effect on differentiation was assessed at days 1, 3, 5, and 7 by western blot analysis, and supplementary immunohistochemical analysis at days 1, 4, and 7 of markers of differentiation - muscle regulatory factors: MyoD and myogenin, markers of the cell cycle p21, PCNA, and the integral signalling molecule, p38MAPK. TNFα supplementation at day 1 tended to positively regulate early markers of differentiation. With continued supplementation however, markers of differentiation decreased dose dependently in treated cultures as the initial effect appeared to be reversed: A trend towards a dose dependent decrease in MyoD, myogenin and p21 protein existed in treated cultures at days 3, 5, and 7. These findings were significant at day 5 (p21, p<0.05), and day 7 (myogenin, p<0.05). A significant dose dependent decrease in p38 phosphorylation was evident at day 3 (p<0.05), while phospho-p38 was dose dependently increased at day 7 (p<0.05). Taken together, these data show that TNFα supplementation for 24 hours following the induction of differentiation in vitro, tends to increase levels of early markers of differentiation, and with continued TNFα supplementation decrease markers of differentiation in a dose dependent fashion. This study provides a comprehensive characterisation of the dose and time dependent effects of TNFα on satellite cell differentiaton in vitro. The model system used in the current study, allows us to make conclusions on more chronic disease states. / AFRIKAANSE OPSOMMING: Tumor nekrose faktor alfa (TNFα) is ‘n pleiotropiese sitokien wat ‘n wye verskeidenheid, dosis afhanklike, sellulêre effekte te weeg bring. Hierdie sellulêre effekte sluit sel groei en differensiasie tot sel dood in. TNFα is by beide spier en niespier inflammatoriese stoornisse soos spier tering in kroniese siektetoestande, en rumatiese artritis betrek. ‘n Fisiologiese rol vir TNFα is egter voorgestel aangesien verhoogde vlakke van die sitokien tydens inisiasie van spier herstel meganismes teenwoordig is: TNFα word deur infiltrerende inflammatoriese selle, asook deur beseerde spier vesels afgeskei. Volwasse skeletspier bevat ‘n populasie stamselagtige selle, sogenoemde satelliet selle. Laasgenoemde word geaktiveer, prolifereer en differensieër volgende spierbesering, om sodoende herstel van beskadigde spier te weeg te bring. Baie navorsing op die effekte van TNFα op satelliet sel differensiasie is onlangs uitgevoer. Dit is egter aansienlik moeilik om volgens hierdie navorsing‘n algehele beeld van TNFα se aksies te vorm aangesien alle modelle wat gebruik word verskil. Ons doel was daarom om ‘n omvangryke assessering van toenemende konsentrasies kronies gesupplementeerde TNFα op differensieërende C2C12 selle op ‘n enkele model uit te voer. Selle was vir 7 dae met of sonder TNFα supplementasie gedifferentieër. Differensiasie was by Dag 0 geïnduseer. TNFα se effek op differensiasie is op dae 1, 3, 5, en 7 deur middel van western blot analise geassesseer. Aanvullende immunohistochemiese bepalings op dae 1, 4, en 7 is verder deurgevoer. Merkers vir differensiasie het die spier regulatoriese faktore MyoD en miogenien, sel siklus merkers p21 en PCNA, asook die integrale sein transduksie molekule p38MAPK ingesluit. TNFα supplementasie by dag 1 het geneig om vroeë merkers van differensiasie positief te reguleer. Met voortdurende supplementasie is die vroeë positiewe effekte (op ‘n dosis afhanklike manier) egter omgekeer: ‘n neiging teenoor (‘n dosis afhanklike) vermindering in MyoD, miogenien en p21 proteïen het in behandelde kulture op dae 3, 5, en 7 bestaan. Hierdie bevindinge was beduidend by dag 5 (p21, p<0.05), en dag 7 (miogenien, p<0.05). A beduidende dosis afhanklike afname in p38 fosforilasie was duidelik by dag 3 (p<0.05), terwyl fosfo-p38 by dag 7 verhoog het met verhoogde konsentrasie TNFα (p<0.05). Bogenoemde saamgevat, dui aan dat TNFα supplementasie 24h volgende die induksie van differensiasie in vitro, verhoogde vlakke van vroeë differnsiasie merkers te weeg bring. Met voortdurende TNFα supplementasie, word differensiasie merkers egter met toenemende dosis verminder. Hierdie studie voorsien ‘n omvattende karakterisering van die dosis- en tyd afhanklike effekte van TNFα op satelliet sel differesiasie in vitro. Die model sisteem in hierdie studie gebruik, maak afleidings oor meer kroniese siektetoestande moontlik.

Orientador: Manoel Barros Bértolo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-18T22:39:29Z (GMT). No. of bitstreams: 1 Mendonca_JoseAlexandre_D.pdf: 2535796 bytes, checksum: 374639057a45bad9800020693b3bc4de (MD5) Previous issue date: 2011 / Resumo: Objetivo: Avaliar sinovite pelo ultrassom (US) articular em pacientes com artrite reumatóide (AR) inicial e correlacionar com os dados clínicos, radiográficos e laboratoriais. Pacientes e Métodos: Este estudo avaliou 832 articulações de 32 pacientes (24 mulheres e 8 homens) com AR inicial selecionados no período de 2008 a 2010 do ambulatório de artrite da Universidade Estadual de Campinas, caracterizado por 20 (62.5%) caucasóides e 12 (37.5%) não caucasóides; um tempo médio de doença de 13 meses, com média de idade de 42 anos. Nesta amostra foram detectadas, pelas escalas semiquantitativas cinza (SG) e pelo power Doppler (PD), 173 articulações com sinovite de grau 0 a 3. Foi usado um ultrassom GE LOGIQ XP-linear de alta frequência (8-10 MHz). Todas as mãos foram radiografadas e analisadas pelo score de Larsen com variação de grau entre 0 a V. Resultados: Este estudo evidenciou correlações significativas e positivas entre os dados ultrassonográficos, clínicos e laboratoriais: SGUS e PDUS do punho D e PCR (r=0.41 a 0.42), SGUS do 3ªMTF D, 4ªMTF D com o HAQ - DI (r=0.37 a 0.38), SGUS do 4ªMTF E e o PCR (r=0.42), SGUS do 2ªMTF D e o FR (r=0.40), SGUS-Score 7mod com o DAS28 (PCR) (r=0.38) e o PDUS-Score 7mod com o PCR (r=0.39). Houve correlações significativas negativas com o SGUS 2ªMTCF D com a dose e o tempo de uso MTX (r=-0.36 a -0.37). O PCR nesta amostra pode ser considerado um indicador de atividade inflamatória quando existe sinovite detectada pelo US. Conclusão: A utilização do US mostrou ser uma importante ferramenta na avaliação de AR inicial e dá um suporte mais seguro no diagnóstico para iniciativas terapêuticas mais precisas e seletivas / Abstract: This study evaluated 832 joints of 32 patients (24 women and 8 men) with early RA enrolled for the period 2008 to 2010 of the arthritis clinic of the Universidade Estadual de Campinas (UNICAMP), characterized by 20 (62.5%) Caucasians, 12 (37.5%) non-Caucasians, an average disease was 13 months, with a mean age of 42 years. This sample was detected by semi-quantitative gray scale (GS) and power Doppler (PD) 173 joints with synovitis of degree 0 to 3. It was used a GE LOGIQ XP-linear ultrasound and high frequency (8-10 MHz) transducer. All hands were X-rayed and analyzed by the Larsen score, with grades ranging from 0 to V. This study showed positive and significant correlation between sonographic, clinical and laboratory data: GSUS/PDUS of right wrist and CRP (r = 0.41 to 0.42), GSUS of the right 3ºMTP, GSUS of the right 4ºMTP and HAQ - DI (r = 0.37 to 0.38), GSUS of the left 4ºMTP and CRP (r = 0.42), GSUS of the right 2ºMTP and FR (r = 0.40), GSUS 7mod-score with the DAS28 (CRP) (r = 0.38) and PDUS 7mod-Score to CRP (r = 0.39). There was a significant negative correlation with the right 2ºMCP with dose and duration of MTX use (r = -0.36 to -0.37). The CRP in this sample can be considered an indicator of inflammatory activity, when analyzed separately or with all the joints committed. Using the US was an important tool in the evaluation of RA and gives a more secure support for initiatives in the diagnosis and treatment more precise and selective / Doutorado / Clinica Medica / Doutor em Clínica Médica