No description available.

No description available.

No description available.

No description available.

No description available.

Mitochondrial myopathies are a group of progressive muscle disorders caused by mutations in the mitochondrial genome (mtDNA) for which there is no effective treatment. Culturing of myoblasts from patients with sporadically occurring mitochondrial diseases has suggested that mtDNA mutations may be lower or absent in muscle stem cells (satellite cells). The activation of muscle satellite cells and subsequent repair of muscle fibres may favourably shift the balance of delete to wild-type (WT) mtDNA, thereby decreasing mtDNA mutation load in affected muscle. This research has investigated muscle precursor cells from patients with mitochondrial myopathy due to sporadically occurring mtDNA deletions. This was to determine if they will benefit from attempts to “gene shift” the balance of WT and mutated mtDNA in their muscles using high intensity resistance training. Fluorescently Activated Cell Sorting (FACS) on the basis of CD56 (NCam) was used to isolate satellite cells and real time PCR to analyse them. In all eight patients investigated mtDNA deletions were detected in satellite cells at levels similar to mature muscle. In most of these patients the mtDNA deletions were lost during the culturing of their myoblasts. In some patients, however, the mutation was maintained, although there was a gradual decline in mutation load as the myoblasts headed towards differentiation. It was hypothesised that this difference between patients in the maintenance or loss of mutations in their myoblasts was attributable to an mtDNA bottleneck effect at the point of satellite cell activation. A second selection point occurred during the process of myoblast proliferation, possibly mediated by segregation of WT and delete mtDNA after cell division. Daughter cells that inherit large amounts of delete mtDNA will be unable to continue to proliferate. If efforts to “gene shift” in these patients will involve the activation of satellite cells to repair damaged muscle, it is paramount that this process does not exhaust the muscle stem cell pool. Satellite cell numbers have been determined in patients harbouring sporadically occurring mtDNA deletions, who will be considered potential beneficiaries of exercise based interventions. No significant difference was observed in satellite cell numbers when patients were compared to controls. In addition, a single patient was examined for satellite cell numbers over eleven years and no reduction in numbers was found. Given that the large majority of single deletion patients will lose their mtDNA mutation during the process of muscle regeneration and that they will not suffer from an exhaustion of the satellite cell pool, “gene shifting” remains a viable therapy in these patients. However, the mechanisms behind the process are somewhat different to what was originally hypothesised.

No description available.

Dystonia is a movement disorder that manifests itself in many forms, from the relatively benign to the extremely severe. It is a disabling condition whose aetiology is unclear and whose treatments are largely unsatisfactory.;The purpose of the work presented in this thesis is to explore the pathophysiology of focal dystonia by utilising the relatively new and powerful tool of Functional Magnetic Resonance Imaging (fMRI). By understanding the benefits and limitations of this technique a number of different studies were designed to further explore the role of the brain in the genesis of this condition. It is hoped that from these investigations a greater understanding of the cortical activations associated with focal dystonia can be elucidated and further theories as to it pathogenesis proposed.;This thesis will be presented in seven chapters outlining the clinical condition of focal dystonia and its place amongst the larger group of dystonias. This includes a review of the current literature on dystonia pathophysiology. Following this the methods used in the investigations will be presented. In the following four chapters the four studies undertaken will be presented and discussed. Finally a summary of the thesis, its findings and limitations and ideas for future investigation will be presented.;In addition to the work presented in this thesis a number of other projects were undertaken in collaboration with others these will be referred to within the thesis, albeit in much less detail.

Myostatin is a negative regulator of muscle mass, and several strategies are being developed to knock down the expression of the myostatin gene as a means to bring about improvements in muscle wasting conditions, including Duchenne muscular dystrophy (DMD). Improved muscle regeneration in the absence of myostatin has been demonstrated in mdx mice by-crossing them with myostatin null mice. Increased muscle strength and improved dystrophic pathophysiology has been found in the mdx mice treated with myostatin antibodies, purified myostatin propeptide (natural binding partner of myostatin) with a mouse fusion protein and AA V -mediated transfer of propeptide. Virus-based strategies have the major drawbacks of uncontrolled insertion into the target genome and undesirable immune response; whereas, injecting binding partners to the target-tissue might have low sustainability over a longer period of time. In this study the design and use of anti sense oligonucleotides (AOs) to manipulate myostatin pre-mRNA splicing and knockdown myostatin has been described. AOs of both 2'O-methyl RNA (2'OMePS-with a phosphorothioate backbone) and phosphorodiarnidate morpholino (PMO) chemistries were designed using different bioinformatics algorithms. Efficiency of destructive myostatin exon skipping was then demonstrated and evaluated comparatively by oligomer transfection of cultured muscle cells, and RT-PCR and bioactivity analyses. Sustained and high levels of destructive exon skipping of the myostatin mRNA, and increases in skeletal muscle mass and fibre sizes was observed up toi months following a single injection of Vivo-PMO (PMO conjugated to a cell-penetrating octa-guanidine moiety) into the tibialis anterior muscle in normal mice. The efficiency of Vivo-PMO was also compared to a PMO conjugated to a cell penetrating peptide moiety (B-PMO) by single intra -muscular treatment of wild type mice. Weekly intravenous injections of Vivo- PMO in normal mice also lead to myostatin exon skipping in selected skeletal muscles, and associated increases in tissue mass, cross-sectional area, and average fibre diameter. Dual exon skipping of myostatin and dystrophin was also carried out successfully in mdx mice. These studies indicate that (i) anti sense-mediated destructive exon skipping can be induced in the myostatin RNA, (ii) anti sense AO treatment reduces myostatin bioactivity and enhances muscle mass in vivo, and (iii) AO-induced myostatin exon- skipping may be a potential therapeutic strategy to counter muscular dystrophy, muscular atrophy, cachexia and sarcopenia.

The overarching aims of this work were to explore the clinical construct of myofascial trigger point pain syndrome, its diagnosis in clinical practice, and its treatment with acupuncture dry needling.