published_or_final_version / Physiology / Master / Master of Philosophy

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No description available.

No description available.

No description available.

Muscle protein is a major constituent of the animal body and it has been the subject of extensive investigation. Many of the individual skeletal muscle proteins have been studied in connection with their role in muscular contraction. As muscular protein is an important source of food for humans its palatabiliy, processing and storing characteristics are of great interest to the food chemist. It is well established that meat flavour precursors are present in the water extractable fractions of meat and it seems likely that the water soluble proteins are involved in the development of the cooked meat flavour. [...]

The purpose of this study was to investigate the reliability of three different electromyography (EMG) detection systems commonly used to acquire EMG data from the pelvic floor muscles (PFM) at rest, during maximum voluntary contractions (MVCs) and during a coughing task. Twelve nulliparous women between the ages of 24 and 40 participated in the study. EMG data were recorded from each side of the pelvic floor using surface (Femiscan™ and Periform™ vaginal probes), and fine-wire electrodes while subjects performed three repetitions of each task in supine and in standing. RMS amplitudes of baseline and peak PFM activity were computed from the data acquired during the MVC and the coughing tasks. The peak RMS amplitudes from the cough data were also normalized to each subject’s MVC and report as a percent of their maximum voluntary electrical activation (% MVE). Signal to noise ratio (SNR) was calculated for each task. Comparisons were made between the RMS amplitudes and SNR recorded from each side of the PFM. Between-trial and between-day reliability was determined using a variety of measures including intraclass correlation coefficients (ICC), coefficients of variation (CV) and mean absolute difference (MAD). The reliability of the different devices was compared using the MAD normalized to average signal amplitude (nMAD). The results indicated that the EMG data recorded from the right and left sides of the PFM were different, therefore the EMG data acquired from each side of the pelvic floor were analyzed separately. Between-trial reliability assessed by ICC was good for all the devices (left and right average ICC(3,1) = 0.80 – 0.96); the CVs supported these findings (average CV = 12.4 – 17.1%) Between-day reliability was poor and inconsistent across all devices as tasks. When the cough data were normalized however, the between-day RMS amplitudes were very consistent (79.5 – 90.2% MVE). Each device recorded consistent activation amplitudes within a given day. Between-day reliability results indicate that EMG data recorded on separate days with these instruments should not be compared unless data can be normalized. Clinicians and researchers are cautioned to normalize their data if day-to-day comparisons in EMG amplitude are to be made using data recorded with these devices. / Thesis (Master, Rehabilitation Science) -- Queen's University, 2007-12-14 17:31:34.552

The myofibrillar proteins, myosin and actin, were quantitated using N$ sp tau$-methylhistidine determined from selected avian white and red skeletal muscles of randomly chosen young and adult white Leghorn chickens. No significant difference (P = 0.01) was noted with respect to muscle type or age in N$ sp tau$-methylhistidine levels which ranged from 0.383 to 0.637 g/kg protein, translating into a myofibrillar protein content ranging between 532.68 to 579.77 g/kg protein. The connective tissue and collagen content, on the other hand, were calculated using 5-hydroxylysine levels in muscle tissue (0.276 to 1.273 g/kg protein) and were found to be significantly higher (P $<$ 0.01) in avian red muscle tissue ranging from 50.19 to 53.80 g/kg protein as compared to white muscle tissue (13.41 to 19.43 g/kg). / It has also been demonstrated that native skeletal muscle actin isolated from three different species, and cardiac muscle actin isolated from bovine and porcine muscle tissue, who highly conserved amino acid compositions and contain 1 mole of N$ sp tau$-methylhistidine per mole of actin.

No description available.

The gastrocnemius muscle was removed from the hindlimb of female rodents, minced into 1mm3 fragments and autotransplanted. Experimental groups had the sural or tibial nerves laid in the mince as follows: both nerves (BN), sural only (SN), tibial only (TN) or no nerve (NN). Animals were sacrificed 45 days postsurgery and the regenerate and contralateral muscles studied for fiber composition and aerobic capacity. Regenerate mass and aerobic capacity were significantly less than control and followed the order BN > TN > SN > NN. The percentage of Types I, IIA and IIB fibers were also different between treatment groups. The data suggests (1) either a more rapid development of axons associated with IIA fibers following nerve transection or greater reinnervation capacity, and/or (2) a shift in the relative number of these axons in the regenerating nerve.