3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item Evaluation of the South African army physical training programme: fitness attained and injuries sustained(1985) Gordon, Neil FarrylPhysical fitness has remained an essential requisite of modern-day armed forces. Despite considerable advances in the science of exercise training, the South African Army physical training programme has remained essentially unaltered for over a decade. Furthermore, it has been suggested that the efficacy of South African Army basic training centres might be limited by the injurious nature of the physical training modes used. The present 3-part investigation was therefore designed as an initial evaluation of the South African Army physical training programme in terms of both physical fitness attained and exertion-related injuries sustained. In Part I of this study, the effect of 1 year South African Army training on endurance fitness was investigated. The pre-military training maximal 02 consumption of 53.14 mg.kg-1.min-1 did not change significantly during the course of the study. In contrast, lactate turnpoint (m-g O2 ,kg- .min-J") and maximal treadmill performance time were moderately enhanced (7.5% and 8% increase, respectively, p<0.05) by the initial 10-week basic training programme. A further analysis of the results indicated that this endurance training effect was limited to the average and, in particular, the below-average fitness recruits. Although this could be regarded as an adequate situation, the effec= tiveness of the physical training was limited in that 17% of recruits were unable to complete the post-basic training exercise test as a result of exertion-related injuries; of these recruits more than 50% had initial below-average fitness levels. Furthermore, the observed beneficial effect of basic training on recruit endurance fitness levels was transient in nature, the values on completion of 1 year military training being essentially unaltered from those existing prior to military conscription. This preliminary assessment of the South African Army physical training programme demonstrates a need for the introduction of changes during and, in particular, after basic training. In Part II of this study, the effect of 1 year South African Army training on muscular strength, power, power- endurance, speed, and flexibility was investigated. When considering the entire study group, a significant enhance= ment by basic training was observed for the isokinetic muscular strength of the right elbow extensors alone (17% increase, p <0.05). Stratification of training responses on the basis of initial recruit fitness levels revealed significant (p<0.05) improvements with basic training for all measures of muscular strength, power, power-endurance, and speed, but not flexibility, in the below-average fitness recruits. In contrast, with the exception of elbow extensor strength, fitness levels of the average and above-average recruits were not improved by basic training. Furthermore, for all recruit fitness groups, values documented on completion of 1 year military training differed insignificantly from those recorded prior to military conscription. Although further research (aimed at assessing the physical requirements of various military work and emergency situations) is needed to evaluate the desirability of the observed selective enhancement of recruit fitness levels, it is evident from the present data that greater emphasis should, at the very least, be placed on flexibility training and physical conditioning after basic training. Finally, in Part III of this study the incidence and nature of exertion-related injuries sustained at a large South African Army basic training centre were studied. A total of 404 separate injuries were incurred by 359 of 947 recruits during the 10-week basic training cycle. Of these injuries, 18.3% were sustained with (Group 1) and 81.7% without (Group 2) an obvious sudden acute precipitating event. Exertion-related injuries were responsible for a loss of 2 711 recruit-days of basic training. While the knee sustained the largest number of Group 2 injuries, lower-leg injuries resulted in the greatest loss of basic training time. Fourty two separate radiographically confirmed stress fractures were incurred by 39 recruits, the incidence of recruits with stress fractures being 4.12%, a value considerably higher than that of the United States Army. These data leave little doubt that the injurious nature of the South African Army basic training programme studied is costly in terms of training time lost and may prohibit large numbers of recruits from deriving the optimum conditioning benefits.Item Systemic lupus erythematosus: the Johannesburg experience(1986) Morrison, Richard C. A.This study is a predominantly retrospective analysis of patients in Johannesburg who presented with Systemic Lupus Erythematosus at 12 years of age or older. Johannesburg is situated at high altitude and has a high level of ultraviolet light irradiation/ a known exacerbating factor of the disease. This study draws comparisons with reported disease characteristics of lupus patients elsewhere in the world. In addition/ it examines differences in the clinical manifestations of the disease amongst the principle South African racial groups.Item Colorectal cancer (CRC) in young, black South Africans: a Morphological, Immunohistochemical and Molecular study(2007) Cronje, LeandraBackground: Amongst black and white patients a disproportionately large number of young blacks present with colorectal cancer (CRC) in South Africa. We proposed that the comprehensive morphological and molecular analysis of a subset of cases might link them to the features associated with either the so-called “serrated pathway” or the hereditary pathway. Such an analysis could direct the diagnosis and treatment of similar patients in an effort to improve prognosis. Materials and Methods: Pathological review of 1732 cases and molecular analysis on a subset of these cases were retrospectively investigated, without knowledge of family history. Determination of the CpG island methylator phenotype (CIMP) was performed at five loci (methylated in tumour loci MINT1, 2 and 31, and the promoter region of the hMLH1 and MGMT genes) using methylation-specific PCR. Microsatellite status was determined through a multiplex PCR process involving the 5 loci specified by the National Cancer Institute. BRAF and KRAS gene status was determined by real-time PCR. Results: Eighty five percent of young patients (<50 years) were black (p < 0.000), predominantly male (56%; p = 0.026) with proximal tumours (25%; p = 0.064). These patients showed significantly more poorly differentiated tumours (p = 0.001) and extracellular mucin (p = 0.006). Molecular analysis revealed young blacks tended to present with loss of protein expression of the mismatch repair (MMR) proteins hMLH1, hMSH2, hMSH6 and MGMT, which resulted in a low MSI status. Overall methylation phenotype in these patients was low, together with the incidence of mutant KRAS genotype. Young white patients less frequently showed loss of mismatch repair protein expression, but MSI-H resulted from hMLH1 promoter hypermethylation in association with KRAS gene mutations and wild-type BRAF although this phenomenon may relate to the small numbers available for study. Conclusion: Many young black patients may develop CRC through the accumulation of mutations due to MSI that resulted from loss of MMR protein expression. These features are associated with hereditary nonpolyposis colorectal cancer (HNPCC). In contrast, young white patients in this series presented with features reminiscent of sporadic CRC characterized by high levels of CIMP and MSI that results from promoter methylation of the hMLH1 gene, as may be identified in the serrated neoplasia pathway.Item The chemotaxonomy and biological activity of salvia stenophylla ( lamiaceae ) and related taxa(2003-10-13) Gono-Bwalya, AngelaSalvia stenophylla Burch, ex Benth. (Lamiaceae) is a perennial aromatic herb, which is widespread in the high altitude areas of the central and eastern parts of South Africa and also occurs in southwest Botswana and central Namibia. It is closely related to Salvia runcinata L. f. and Salvia repens Burch, ex Benth., with which it forms a species complex. The most recent revision of southern African Salvia species is that by Codd (1985). In this revision, the most important characters used in delimiting the three taxa were corolla size, calyx size and trichome density. As a result of intergrading morphological characters, the specific limits between the three taxa are not clear and positive identification of typical material is often difficult. Taxonomic delimitation through use of chemical characters was therefore the principle objective of this study. The taxa represented in this species complex are known in folk medicine and plant extracts have been used in the treatment of urticaria, body sores, and stomach ailments and as a disinfectant. S. stenophylla is reported to contain a-bisabolol, a compound that has anti-inflammatory properties. Based on the traditional uses of these plants and the international use of a-bisabolol to develop active cosmetic products, establishing a scientific rationale for the known uses was an important secondary objectiveItem Aspects of high-level trimethoprin resistance in gram-negative bacteria isolated in South Africa(1991-02-07) Wylie, Barbara ATrimethoprim is a broad-spectrum antimicrobial agent frequently used either in combination with sulphamethoxazole (cotrimoxazole) or alone in the treatment of urinary and respiratory tract infections. Since the introduction of this drug in 1969 resistance to it has been monitored in several centres in Europe continuously but only intermittently in the United States of America and developing countries in Africa, Asia, Central and South America. In Europe the incidence of trimethoprim resistance has increased significantly in the last 20 years. In developing countries no trends have been established but the incidence of resistance appears to be greater in these countries than in Europe or the USA.Item The preformulation investigation of a combination anti-tuberculosis dosage form(1998-06-04) Ebrahim, SalmaTuberculosis control in South Africa continues to be a major challenge with 90 000 new cases reported in 1995. Major contributory factors towards these epidemic proportions are patient non-compliance and the occurrence of drug resistant tuberculosis. Fixed drug combinations of anti-tuberculosis drugs have been reported to reduce the possibility of resistance arising to any one of the drugs in combination and to improve compliance. However, the combination anti-tuberculosis drugs available at present still suffer the disadvantage of patients having to take 6 tablets per day. Therefore, the purpose of this project was to investigate a formulation that would reduce this disadvantage.Item Patterns of health and nutrition in South African Bantu. Introduction.(1954) Kark, Sydney lItem Patterns of health and nutrition in South African Bantu.Section A(1954) Kark, Sydney lItem Y-chromosome variation in the South African 'coloured' population(2004) Motladiile, Thejane WilsonGenetic polymorphisms within the non-recombining portion of Y-chromosome (NRY) preserve a record of human paternal genetic heritage that has persisted to the present, allowing human evolutionary inference, population affinity and demographic history, to be elucidated. To elucidate the geographic origins of the paternal ancestry of the present- day South African (SA) ‘Coloured’ population, a total sample of 167 individuals consisting of Cape Malay (N=54) and ‘Coloured’ groups from Cape Town (N=48) and Johannesburg (N=65) were analysed at 21 binary and eight short tandem repeat (STR) polymorphic loci within NRY. A SA White sample (present study, N=97) as well as other presumed parental populations were included for comparative analysis. Haplotypes constructed using both biallelic haplogroup and STR haplotype data assisted in resolving the geographic regions of origin of Y-chromosome in these groups. Altogether the proportions of African, European and Asian contributions were estimated to be 0%, 18.5% and 46.3% in the Cape Malay, 31.3%, 25% and 20.1% in the Cape ‘Coloureds’, and 24.6%, 40% and 16.9%, in the ‘Coloured’ group from Johannesburg. Those haplotypes that could not be unambiguously resolved to European or Asian origins were referred to as Eurasian lineages, and constituted 35.2%, 22.9% and 18.5% of Y- chromosomes in the Cape Malays, Cape ‘Coloureds’ and Johannesburg ‘Coloureds’, respectively. While the ‘Coloured’ groups currently residing in Cape Town and Johannesburg were not significantly different from each other, both groups were significantly different from the Cape Malay population. This was further supported from the association of these groups in population trees. For the most part, these data corroborate historical data concerning the history of ‘Coloured’ populations, but is the first study to show how males have contributed in shaping the gene pool of the ‘Coloured’ population from South Africa.Item Viability of high performance liquid chromatography as a method of mycobacterial identification in South African laboratories(2001) Naidoo, ShironaPathogenic mycobacterial infection was in recent decades a health concern so well controlled that eradication seemed imminent. However, it is once again reaching epidemic proportions following the increasing prevalence of AIDS. One important means of curbing this resurgence, is a robust method that has the capability of identifying to a species level speciating disease causing mycobacteria in a matter of days. Several new methodologies are now available that enable dramatic reductions in turn-around times. In this study High Performance Liquid Chromatography was investigated to determine how this system compared with the current mycobacterial system of methodologies adopted in South African laboratories. Four species of pathogenic mycobacteria, with a high prevalence in South Africa, were tested in a sample size of 80. Samples were subjected to HPLC, Gene Probes and Biochemical testing. HPLC was the most capable of identifying the mycobacteria to species level displaying a sensitivity to the organisms of 96.25 %. Gene probes and Biochemical testing had sensitivity values of 82.5 % and 80 % respectively. HPLC was also more cost efficient and displayed a wider range of identification. It is therefore suggested that HPLC replace Gene probes and Biochemical testing for purposes of MOTT identification in the comprehensive mycobacterial identification system. The result is a time saving of at least 3 weeks and a cost reduction of approximately 30 %. The large initial capital investment required for the implementation of the HPLC system is justified by the long term cost saving as well as the additional utility derived from early identification. As a consequence treatment is not empiric but rather tailored to the organism infecting the patient, hence preventing multiple drug resistance developing and ultimately saving a life through rational drug use.