The problem of this study was to review within Dallas and Tarrant Counties the relationship between an "influenza-like" illness within six months prior to contracting Mycobacterium kansasii disease. An interview instrument was developed and used during personal interviews to collect data. Additional data of case rates and reported cases was compiled from local and national governmental public health agencies. Analysis of the data indicated no significant difference between an individual contracting an "influenzalike" illness within six months prior to the acquiring of Mycobacterium kansasii disease. Therefore, there is no relationship between having had influenza-like symptoms within six months of contracting Mycobacteria kansasii.

Thesis (M.Sc.(Microbiology)) -- University of Limpopo, 2022 / This study aimed to investigate antimycobacterial and cytotoxic compounds from Cassia petersiana. Cassia petersiana was selected for the current study based on its traditional use for treating tuberculosis (TB) symptoms. Extraction is an important step in the use of medicinal plants; hence, solvents of varying polarity were employed to extract a wide range of compounds where chloroform was the best extractant (67 mg). As there is no relation between the amount of plant material extracted and the bioactivity of the extracts, standard tests were used to determine the presence of different phytochemical constituents from Cassia petersiana and the total phenolic, flavonoid, and tannin contents were quantified using colorimetric assays. It was revealed that all the tested phytochemical constituents were present, and it was proven that phenolic compounds were the most abundant, followed by the tannins, while the flavonoids were the least among the common phytochemical constituents quantified. The phytochemical compounds were further profiled on thin-layer chromatography (TLC) and developed in BEA, CEF, and EMW solvent systems. Colourful compounds which indicated diverse phytochemicals were visualised with both vanillin-sulphuric acid and ultraviolet light on the phytochemical chromatograms and good separation of the compounds was from the BEA solvent system. The qualitative and quantitative antioxidant activity and antimycobacterial activity assays were used to evaluate the extracts from Cassia petersiana. Minimal antioxidant activity was observed on the qualitative antioxidant activity profile. These findings correlated with the minimal quantity of antioxidants from extracts of Cassia petersiana from the quantitative antioxidant assays; ferric reducing power and DPPH scavenging activity assays. Cassia petersiana extracts had bioactivity against Mycobacterium smegmatis as indicated by the lowest MIC value. The cell viability effects of the acetone crude extract from Cassia petersiana were evaluated against the tryptophan hydroxylase-1 (TPH-1) macrophage cells. Large scale extraction procedure was employed to extract a sufficient amount of plant material in preparation for the isolation of the bioactive compound. Bioassay-guided fractionation combined with column chromatography and TLC were used to isolate and purify the bioactive compound from the n-hexane extract of Cassia petersiana. The purified isolated compound was elucidated as β-sitosterol, which showed remarkable bioactivity against Mycobacterium smegmatis only on the TLC-bioautographic assay, while the quantitative antimycobacterial activity was higher xx with the MIC value of 2.5 mg/mL. Although β-sitosterol is known as a good antioxidant, it showed no antioxidant activity on the qualitative antioxidant activity assay. Therefore, further studies, including in vivo assay, are recommended on the isolated compound to evaluate its biological activities before consideration of its use in the development of alternative drugs.

One of Africa’s neglected tropical diseases, African Trypanosomiasis, is not only fatal but also has a crippling impact on economic development. Heat shock proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. The expression of heat shock proteins increases during these heat shock conditions, and this is considered to play a role in differentiation of these vector-borne parasites. Heat shock protein 70 (Hsp70) is an important molecular chaperone that is involved in protein homeostasis, Hsp40 acts as a co-chaperone and stimulates its intrinsically weak ATPase activity. In silico analysis of the T. brucei genome has revealed the existence of 12 Hsp70 proteins and 65 Hsp40 proteins to date. A novel Hsp70, TbHsp70.c, was recently identified in T. brucei. Different from the prototypical Hsp70, TbHsp70.c contains an acidic substrate binding domain and lacks the C-terminal EEVD motif. By implication the substrate range and mechanism by which the substrates are recognized may be novel. The ability of a Type I Hsp40, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated. The main objective of this study was to biochemically characterize TbHsp70.c and its partnership with Tbj2 to further enhance our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed chaperone activities in their ability to suppress aggregation of thermolabile MDH. TbHsp70.c also suppressed aggregation of rhodanese. ATPase assays revealed that the ATPase activity of TbHsp70.c was stimulated by Tbj2. The targeted inhibition of the function of heat shock proteins is emerging as a tool to combat disease. The small molecule modulators quercetin and methylene blue are known to inhibit the ATPase activity of Hsp70. However, methylene blue did not significantly inhibit the ATPase activity of TbHsp70.c; while quercetin, did inhibit the ATPase activity. In vivo heat stress experiments indicated an up-regulation of the expression levels of TbHsp70.c. RNA interference studies showed partial knockdown of TbHsp70.c with no detrimental effect on the parasite. Fluorescence microscopy studies of TbHsp70.c showed a probable cytoplasmic subcellular localization. In this study both TbHsp70.c and Tbj2 demonstrated chaperone activity and Tbj2 possibly functions as a co-chaperone of TbHsp70.c.

The treatment of tuberculosis (TB) is currently a challenge due to multi- and extensively drug resistant strains of Mycobacterium tuberculosis. Mycobacterium bovis and M. tuberculosis cause clinically indistinguishable tuberculosis in humans. Both M. bovis and M. tuberculosis have been isolated from humans and animals. Plant species contain antimicrobial compounds that may lead to new anti-TB drugs. To conduct in vitro antimycobacterial assays, it is important to include current clinical isolates as new strains of bacteria might be circulating under the ongoing climate change environment. The overall goal and objectives of this study were to isolate and characterize mycobacteria species from South Africa, to test some selected plant species of the Anacardiaceae family for antimycobacterial activity using some of the newly isolated and reference strains of mycobacteria followed by cytotoxicity evaluation of the most active plant species, and finally the isolation and characterization of at least one compound from the most active and least toxic plant. This study led to the discovery of a new isolate of Mycobacterium Avium Complex species from black wildebeest. Other non-tuberculous mycobacteria and M. bovis isolates were identified from other animal species. Five out of 15 plant species screened showed good activity against Mycobacterium species. Five antimycobacterial compounds were isolated from Searsia undulata, the most active plant species. Two out of the five compounds were identified, and one compound appears to be novel, but both compounds have been isolated for the first time from Searsia undulata. An incidental finding was the potential anticancer property of extracts of Searsia undulata. Recommended future activities include isolation and identification of more active compounds from Searsia undulata which were visible in bioautography analysis, as well as synergy evaluation of antimycobacterial activities of the different compounds with current anti-tubercular drugs. / Environmental Sciences / Ph. D. (Environmental Science)