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Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, 2014. / Aim: To determine the effect of long axis manipulation of the third metacarpophalangeal joint (MCP) on articular surface separation, peri-articular soft tissue movement and joint cavitation. Participants: Forty two right-handed healthy individuals between 18 and 28 years of age from the Durban University of Technology campuses, KwaZulu Natal. Methodology: Written informed consent was obtained from each participant. A case history, physical examination and a hand and wrist orthopaedic assessment was conducted for each participant. Study specific data, such as sex, age, height and weight were recorded. A diagnostic ultrasound (US) scan was done to the left third MCP joint for each participant while distractive manipulation was applied to the joint. The presence or absence of audible release was noted and the tension levels applied to the joint was measured with a digital tension meter. Joint surface separation (JSS), synovial membrane position (SMP), gas bubble presence and location were assessed on the US recordings at baseline, just prior to cavitation, at maximum traction and in the post-traction resting joint. IBM SPSS version 20 was used to analyse the data. Independent sample t-tests were used to compare the means between the two groups and the associations were compared using Pearson’s chi square tests. A p value <0.05 was considered as statistically significant. Results: Long axis manipulation resulted in audible release in 22 of the participants (Group and no audible release in 20 of the participants (Group 2). No significant difference in joint surface separation or the synovial membrane position could be established between MCP joints that cavitated and MCP joints that did not cavitate at the baseline, as well as in maximum traction and in the post-procedure resting joint (p > 0.05; t-test). Hyperechoic gas bubbles were present in 21 of the 22 participants of Group 1 and no gas bubbles could be visualised in the participants in Group 2. The presence of intra-articular hyperechoic gas bubbles was highly associated with audible release (p < 0.001; Pearson’s chi square test). Due to the predefined features of cavitation, gas bubble inception was could not be detected in the Group 1 participants prior to cavitation. In Group 1, 95.5% of the gas bubbles were present in the middle third of the joint at maximum traction. At the post traction resting joint evaluation, no gas bubble was evident in 42.9% (n = 9) of the joints; 42.9% (n = 9) indicated bubbles were present only in the dorsal third, whilst 9.5% (n = 2) presented bubbles in the middle and dorsal third; and in one case gas bubbles were seen in the dorsal, middle and ventral thirds of the joint space. The mean manipulative force recorded in participants in which gas bubble inception took place during manipulation was 5.7 kg, and in those with no gas bubble inception was 12 kg. There was a significant difference between the mean traction force applied to those with and to those without a gas bubble appearance (p < 0.001; t-test). Conclusion: No significant differences were observed between the cavitation and non-cavitation groups for the joint surface separation and synovial membrane movement at various stages of manipulation. A significant association was established between the audible release of a joint that was manipulated and the appearance of intra-articular gas bubbles or micro-bubbles. The mean traction force that was required to cause cavitation was significantly lower than the force to which joints with no cavitation were tensioned. The findings concur with those of previous studies that cavitation is a necessary component of joint manipulation.

As cartilage tissue has limited repair capacities, tissue engineering has emerged as a promising alternative for cartilage repair. The scaffold is a primary component of the tissue engineering design, yet little information exists regarding the effects of polymer and scaffold properties on tissue growth. In this study, we have developed a novel scaffold, PLG microspheres, for use in cartilage tissue engineering, which has the capacity for alterations in polymer and scaffold. We examined the effects of molecular weight, hydrophobic capping, delivery of Mg(OH)2, microsphere size, and controlled release of IGF-I. Our findings demonstrated that polymer parameters distinctively affect tissue and matrix output. Specifically, micro spheres with high molecular weight polymer produced tissue with high GAG content and tissue mass in vivo and in vitro, while micro spheres with capped polymer induced steady tissue and matrix accumulation, but may have precluded cell attachment. Release of buffer to the growing cartilage had negative effects on tissue formation in vivo and in vitro. Additionally, increasing microsphere diameter generated more samples with center of necrotic tissue. The presence of microspheres induced greater cartilage mass and matrix content than cartilage from cells alone. Delivery of IGF-I induced a dose-dependent effect on matrix and tissue production in vivo, with the highest effective load of IGF-I (0.3%) generating the most matrix and tissue accumulation. In contrast, the in vitro IGF-I dose-dependent effect induced on matrix and tissue production peaked at a dose of 0.02% IGF-I, with higher doses generating less tissue and matrix. Taken together, changes in polymer or scaffold composition and release of growth factor can be optimized to form cartilage with enhanced tissue parameters. Moreover, these results demonstrate a novel scaffold with potential to support cartilage regeneration and provide simultaneous drug delivery.

Cartilage Tissue Engineering. Joint pain and functional impairment due to cartilage damage from osteoarthritis and other means is a major source of disability for adults the world over. Cartilage is an avascular tissue with a very limited capacity for self repair. Current medical and surgical approaches to cartilage repair also have limited efficacy, and in all cases fail to completely restore a normal, healthy cartilage phenotype. Tissue engineering is a relatively new approach to cartilage repair that seeks to fabricate a replacement tissue, indistinguishable from healthy, native tissue. The basic idea of the tissue engineering approach is to seed tissue synthesizing cells into a shapeable, biocompatible/bioabsorbable scaffold that serves as a temporary extracellular matrix with a localized source of bioactive molecules to direct the development of new tissue. The challenge of tissue engineering is to identify cells, scaffolds, and growth conditions that will be optimal for tissue regeneration. The goal of the current studies was to evaluate one aspect of all three of the major components of cartilage tissue engineering: cell source, scaffolding material and preparation, and controlled growth factor delivery. We evaluated the chondrogenic potential of human nasal chondrocytes grown in calcium alginate in an in vivo culture system, the potential of computer-aided design and injection molding with calcium alginate to reliably reproduce complex geometries with high dimensional tolerances, and the potential for the controlled release of TGF-β1 from calcium alginate modified by the covalent addition of a recently discovered TGF-β binding peptide. We found that adult human nasal chondrocytes show significant chondrogenic potential when grown within an alginate scaffold. We also found that alginate is readily amenable to an injection molding process that utilizes precision made molds from computer-aided design and solid free form fabrication, allowing for the fabrication of tissue engineered constructs with very precise shape fidelity. Additionally, we found that calcium alginate could be reliably modified by the covalent addition of peptides, and that the addition of a newly discovered TGF-β binding peptide delayed the release of pre-loaded TGF-β1. Together these results show some of the encouraging prospects for cartilage tissue engineering. `Menière’s Syndrome.Menière’s syndrome is an inner ear disorder characterized by idiopathic endolymphatic hydrops with associated periodic tinnitus, vertigo, and progressive sensorineural hearing loss. It affects approximately 0.2% of the population, for whom it can be quite devastating. In addition to progressive hearing loss people with Menière’s syndrome are prone to sudden attacks of vertigo and tinnitus that are severe enough that they can lead to falls and potentially serious injury. People subject to frequent attacks are unable to drive, with obvious consequences on standard of living. In the current studies we evaluated the standard animal model of Menière’s syndrome by comparing cochlear turn specific hearing thresholds and the degree of hydrops in that turn. A positive correlation between these had previously been established in the study of human temporal bones from people with Menière’s syndrome, but had not been reported in the animal model. We also evaluated the potential of aminoguanidine, a relatively specific inhibitor of the inducible isoform of nitric oxide synthase, as a neuroprotective therapeutic agent for preservation of hearing in animals with surgically induced endolymphatic hydrops. We found, for the first time, a partial correlation between cochlear turn specific hydrops and hearing thresholds in the most commonly used animal model of Menière’s syndrome, helping to validate the utility of this animal model for future studies. We also found that aminoguanidine did indeed partially preserve hearing in animals with surgically induced Menière’s syndrome. This encouraging result appears to be the first report of a medical intervention protective against hearing loss in an animal model of Menière’s syndrome, and may help us to understand the etiology pathology seen in Menière’s syndrome.

Made available in DSpace on 2015-08-20T17:09:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-23. Added 1 bitstream(s) on 2015-08-20T17:26:30Z : No. of bitstreams: 1 000841548_20160128.pdf: 759734 bytes, checksum: ead02abf55ea1951547807a775c663d9 (MD5) Bitstreams deleted on 2016-01-28T17:44:57Z: 000841548_20160128.pdf,. Added 1 bitstream(s) on 2016-01-28T17:45:38Z : No. of bitstreams: 1 000841548.pdf: 1623935 bytes, checksum: dedbf055acde7dcc862327cd1e1e6078 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O pacu (Piaractus mesopotamicus) é um peixe brasileiro que apresenta elevado interesse econômico para a piscicultura, devido a características como rusticidade e rápido crescimento. O crescimento pós-natal do músculo esquelético em peixes ocorre por hiperplasia e/ou hipertrofia, processos dependentes da proliferação e diferenciação de mioblastos. Uma classe de pequenos RNAs não codificantes, conhecidos como microRNAs (miRNAs), reprime a expressão de mRNAs alvo, e muitos estudos mostram que o miR-1, miR-133, miR-206 e miR-499 regulam diferentes processos no músculo esquelético pelo silenciamento da HDAC4, SRF, Pax7 e Sox6, respectivamente. O objetivo do nosso trabalho foi avaliar a expressão dos miRNAs e de seus supostos mRNAs alvo nos músculos esqueléticos de contração rápida e lenta do pacu durante o crescimento. Nossos resultados mostraram uma correlação inversa entre a expressão dos miRNAs e de seus mRNAs alvo, e houve evidências de que o miR-1, miR-133 e miR-206 podem regular a proliferação e diferenciação de mioblastos. Por outro lado, o miR-499 foi altamente expresso no músculo de contração lenta, sugerindo seu envolvimento na especificação e manutenção do fenótipo lento nas fibras musculares. A expressão dos miRNAs mostrou variações entre diferentes estágios de desenvolvimento e entre fenótipos de contração muscular distintos. Esse trabalho forneceu a primeira identificação do perfil de expressão de miRNAs relacionados ao músculo esquelético no pacu e sugere um importante papel dessas moléculas nesse tecido / Pacu (Piaractus mesopotamicus) is a Brazilian fish with high economic interest for pisciculture due to features such as rusticity and fast growth. Postnatal growth of skeletal muscle in fish occurs by hyperplasia and/or hypertrophy, processes that are dependent on the proliferation and differentiation of myoblasts. A class of small noncoding RNAs, known as microRNAs (miRNAs), represses the expression of target mRNAs, and many studies demonstrate that miR-1, miR-133, miR-206 and miR-499 regulate different processes in skeletal muscle through the mRNA silencing of HDAC4, SRF, Pax7 and Sox6, respectively. The aim of our work was to evaluate the expression of miRNAs and their putative target mRNAs in fastand slow-twitch skeletal muscle of pacu during growth. Our results revealed an inverse correlation between the expression of miRNAs and their target mRNAs, and there was evidence that miR-1, miR-133 and miR-206 may regulate the proliferation and differentiation of myoblasts. On the other hand, miR-499 was highly expressed in slow-twitch muscle, which suggests its involvement in the specification and maintenance of the slow phenotype in muscle fibres. miRNA expression exhibited variations between different development stages and between distinct muscle twitch phenotypes. This work provided the first identification of miRNA expression profiles related to skeletal muscle in pacu and suggests an important role of these molecules in this tissue / FAPESP: 2013/01892-2

Assessments of skeletal muscle functional capacity or bilateral muscular asymmetry often necessitate maximal contractile effort, which exacerbates muscle fatigue or injury. Tensiomyography (TMG) has been investigated in laboratory settings, as a means to assess muscle contractile function following fatigue; however observations have not been contextualised by concurrent physiological measures. TMG has more sparingly been applied in the field, with elite athletes. The aim of this thesis was to examine acute alterations and underlying variations in muscle contractile mechanics, through the application of TMG, contextualised with established physiological measures; and to apply TMG within high performance sports programmes. TMG successfully detected fatigue, evident from reduced strength, by displaying impaired muscle displacement, accompanied by elevated resting muscle tension. Greater asymmetry was detected in individuals with asymmetric strength; however, symmetry was masked during more complex tasks. Increased day-to-day variability was detected among highly trained athletes compared to recreationally active individuals. Acute training adaptations were detected, in contractile mechanics, in individual muscles. TMG could be useful in establishing fatigue status of skeletal muscle without exacerbating the functional decrements of the muscle, whilst also providing useful screening information for detecting asymmetry which may not be apparent during functional actions.

Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2018. / Musculoskeletal disorders (MSDs) are the most common health complaints in the working population and the advancement in technology is a big contributor. Many offices and work spaces have been revolutionised with technological advances, most notably through computer usage, which has become an integral part of life. Intensive use of computers has shown to result in MSDs. The aim of this study was to examine the occurrence of MSDs in a library setting at a University of Technology with the objectives of: determining the prevalence of MSDs in the library staff, to describe the workstations of the staff, and to describe any associations between the workstations and MSDs. This was a cross sectional study at two libraries at a University of Technology with a sample of 59 library staff. The study involved a two part process in which an observational assessment of the library staff was conducted by the researcher with each staff member individually, followed by a questionnaire completed by each participant. The observational checklist was used as a means to assess the ergonomic environment of the library staff. The questionnaire included demographic information, pain-related questions, psychosocial questions, and perception-based questions regarding the participants’ work environment. Statistical analysis was performed using SPSS (version 24), including descriptive and inferential statistics. Statistics included frequencies, measures of central tendency, and variance and measures of association for example chi-square, Cronbach’s alpha and correlation statistics. The study indicated a prevalence of 96% for some kind of MSD. One out of every two participants had reported that the MSDs or pain interferes with their work. Certain risk factors were evident from the study, namely: inappropriate desk height, reaching for items in the work place, noise, inappropriate chairs and inadequate leg room. The most commonly reported MSDs related to neck (55.9%), shoulders/upper arm (55.9%), head (49.2%), and knees/legs (49.2%). The significant associations that were present included head and neck MSDs with noise and upper arm positioning in worker posture and hand pain. Significant rates of MSDs were reported by the participants with half of them reporting that pain caused interference with their work and only a small portion of participants seeking treatment for these conditions. It would be beneficial for the library staff to become more aware of MSDs and their ergonomic environments both at work and privately and to take corrective action to better equip themselves to mitigate MSDs and seek treatment when needed. / M

Orientador: Maeli Dal Pai / Banca: Fernanda Losi Alves de Almeida / Banca: Fernanda Antunes Alves da Costa / Resumo: O pacu (Piaractus mesopotamicus) é um peixe brasileiro que apresenta elevado interesse econômico para a piscicultura, devido a características como rusticidade e rápido crescimento. O crescimento pós-natal do músculo esquelético em peixes ocorre por hiperplasia e/ou hipertrofia, processos dependentes da proliferação e diferenciação de mioblastos. Uma classe de pequenos RNAs não codificantes, conhecidos como microRNAs (miRNAs), reprime a expressão de mRNAs alvo, e muitos estudos mostram que o miR-1, miR-133, miR-206 e miR-499 regulam diferentes processos no músculo esquelético pelo silenciamento da HDAC4, SRF, Pax7 e Sox6, respectivamente. O objetivo do nosso trabalho foi avaliar a expressão dos miRNAs e de seus supostos mRNAs alvo nos músculos esqueléticos de contração rápida e lenta do pacu durante o crescimento. Nossos resultados mostraram uma correlação inversa entre a expressão dos miRNAs e de seus mRNAs alvo, e houve evidências de que o miR-1, miR-133 e miR-206 podem regular a proliferação e diferenciação de mioblastos. Por outro lado, o miR-499 foi altamente expresso no músculo de contração lenta, sugerindo seu envolvimento na especificação e manutenção do fenótipo lento nas fibras musculares. A expressão dos miRNAs mostrou variações entre diferentes estágios de desenvolvimento e entre fenótipos de contração muscular distintos. Esse trabalho forneceu a primeira identificação do perfil de expressão de miRNAs relacionados ao músculo esquelético no pacu e sugere um importante papel dessas moléculas nesse tecido / Abstract: Pacu (Piaractus mesopotamicus) is a Brazilian fish with high economic interest for pisciculture due to features such as rusticity and fast growth. Postnatal growth of skeletal muscle in fish occurs by hyperplasia and/or hypertrophy, processes that are dependent on the proliferation and differentiation of myoblasts. A class of small noncoding RNAs, known as microRNAs (miRNAs), represses the expression of target mRNAs, and many studies demonstrate that miR-1, miR-133, miR-206 and miR-499 regulate different processes in skeletal muscle through the mRNA silencing of HDAC4, SRF, Pax7 and Sox6, respectively. The aim of our work was to evaluate the expression of miRNAs and their putative target mRNAs in fastand slow-twitch skeletal muscle of pacu during growth. Our results revealed an inverse correlation between the expression of miRNAs and their target mRNAs, and there was evidence that miR-1, miR-133 and miR-206 may regulate the proliferation and differentiation of myoblasts. On the other hand, miR-499 was highly expressed in slow-twitch muscle, which suggests its involvement in the specification and maintenance of the slow phenotype in muscle fibres. miRNA expression exhibited variations between different development stages and between distinct muscle twitch phenotypes. This work provided the first identification of miRNA expression profiles related to skeletal muscle in pacu and suggests an important role of these molecules in this tissue / Mestre

Submitted in partial compliance with the requirements for a Master’s Degree in Technology, Durban University of Technology, Durban, South Africa, 2018. / Background: Chiropractors are a unique group of health care professionals who are at risk for developing work-related musculoskeletal injuries. Diversity of daily practice imposes different physical demands on the chiropractor. The present study aims to determine the prevalence of work-related musculoskeletal injuries in chiropractors in eThekwini municipality and selected risk factors associated with work-related musculoskeletal injuries. There are very few studies available that look at the chiropractor holistically in terms of work-related musculoskeletal injuries. However, these existing studies suggest that chiropractors are at a greater risk for the development of work-related musculoskeletal injuries. Method: The study design was a quantitative, cross-sectional, descriptive study utilising a self- administered questionnaire, developed specifically for this research, using an expert group and pilot study. The questionnaire contained sections on personal as well as practice demographics, with questions pertaining to the single most severe work-related musculoskeletal injury, as well as the second and third most severe work-related musculoskeletal injury. Risk factors for work- related musculoskeletal injury were tested by using chi square in the case of categorical variables. In the event of violation of the expected frequencies, the Fisher’s exact test was used to obtain the p-value. Logistical regression was used to obtain odds rations in the presence of more than one explanatory variable. A p-value of <0.05 was used to indicate statistical significance. Results: Sixty-two chiropractors responded, giving a response rate of 64%. The life-time prevalence of work-related musculoskeletal injuries was 69%. A predominance of injuries to the upper extremity (50%) and lower back (28.3%) were recorded. The hand/wrist was the most common anatomical site of injury (31.5%) followed by the lower back. Number of years in practice was considered a risk factor for injury as most injuries occurred within the first five years of practice (41.6%). The likelihood of injury decreases with an increase in the number of years in practice. The majority of injuries affected the soft tissue, including ligament sprains (27.5%) and muscle strains (26.6%) and occurred while the practitioner was performing manipulation (38.2%) of the lumbosacral (80.77%) area with the patient in the side posture (61.53%). Conclusion: The results concur with other studies on work-related musculoskeletal injuries in chiropractors and add insight into risk factors predisposing this population to injury. Chiropractors need to understand the risk factors for occupational injury to implement strategies to avoid risk of injury. / M

Made available in DSpace on 2016-06-07T17:12:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-25. Added 1 bitstream(s) on 2016-06-07T17:16:40Z : No. of bitstreams: 1 000864238.pdf: 3148372 bytes, checksum: a37fda8f4a1502a786d3f1ffe3bda3ff (MD5) / O entendimento dos mecanismos celulares e moleculares envolvidos com os processos de hipertrofia e atrofia muscular têm sido alvo de muitas pesquisas. Tal fato contribui para desenvolvimento de estratégias terapêuticas eficazes para atenuar ou até mesmo bloquear a perda de massa muscular. Neste contexto, fatores miogênicos e microRNAs (miRNAs) têm sido estudados para melhor compreender as respostas adaptativas do músculo esquelético. Os objetivos do presente trabalho foram avaliar as adaptações morfofuncionais, a expressão gênica de fatores miogênicos, anabólicos e catabólicos e a expressão dos miRNAs no músculo esquelético de ratos submetidos à estimulo atrófico, seguido de treinamento físico, aeróbico e resistido. Foram utilizados 80 ratos Wistar machos (80 dias, 250 a 300 g), divididos em 10 grupos (n=8): C: controle; I: imobilizado; C3: controle 3 dias; R3: recuperado sem exercício 3 dias; T3: treinamento aeróbico 3 dias; TF3: treinamento de força 3 dias; C7: controle 7 dias; R7: recuperado sem exercício 7 dias; T7: treinamento aeróbico 7 dias e TF7: treinamento de força 7 dias. Inicialmente, os animais dos grupos I, R3, R7, T3, T7, TF3 e TF7 foram submetidos a um período de 7 dias de imobilização dos membros posteriores. Foram analisados os músculos plantar (Pl - glicolítico e de contração rápida) e sóleo (Sol - oxidativo e de contração lenta). A atrofia muscular foi confirmada pela análise da área de secção transversal (AST) das fibras nos animais dos grupos I e C. Os grupos T3 e T7, foram submetidos a um programa de recuperação muscular com exercício aeróbico (natação) no período de 3 e 7 dias respectivamente enquanto os grupos TF3 e TF7 foram submetidos a um programa de recuperação muscular com exercício resistido (salto). Ao término do experimento os músculos Pl e Sol foram submetidos às análises: morfológica, histoquímica, bioquímica e molecular. Observamos atrofia muscular em... / Understanding the cellular and molecular mechanisms involved in hypertrophy and atrophy processes have been the subject of much research. This fact contributes to development of effective therapeutic strategies to attenuate/block the muscle mass loss. However, myogenic factors and muscle-specific miRNAs have been studied to understand the skeletal muscle adaptive responses. The aim of this study were to evaluate the morphological and functional adaptations, the gene expression of myogenic, anabolic and catabolic factor, and the expression of microRNAs in skeletal muscle of rats submitted to atrophic stimulus followed by physical training. 80 male Wistar rats were used (80 days 250 to 300 g) were divided into 10 groups (n = 8) C: Control; IM: immobilizated; C3: control 3 days; R3: recovered without exercise 3 days; T3: aerobic training 3 days; TF3: strength training 3 days; C7: control 7 days; R7: recovered without exercise 7 days; T7: aerobic training 7 days and TF7: strength training 7 days. Initially, the animals of I, R3, R7, T3, T7, TF3 and TF7 groups were underwent period of hindlimb immobilization by 7 day. Plantaris (Pl - glycolytic and fast twitch) and soleus (Sol - oxidative and slow twitch) muscles were analyzed. Muscle atrophy was confirmed by the analysis of cross-sectional area (CSA) of fibers in groups I and C. The T3 and T7 groups, were underwent a muscle recovery program with aerobic exercise (swimming) 3 period and 7 days respectively while the TF3 and TF7 groups were underwent a muscle recovery program with resistance exercise (jump). At the end of experiment the Pl and Sol muscles were submitted to analysis: morphological, immunohistochemical, biochemical and molecular. Muscle atrophy was observed in both muscles after immobilization, but after 7 days of recovery, only the T7 group showed recovery in CSA. Gene expression data showed: increase in genes involved in muscle atrophy in group I in Sol (MAFbx, PGC-1α and ...