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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

An investigation into the antibacterial activities of medicinial plants traditionally used in the Eastern Cape to treat secondary skin infections associated with burn wounds

Weideman, Liezel January 2005 (has links)
Traditional medicine has a long history of being used for treating various ailments ranging in severity. Although traditional medicine has typically been the health care for the poorest levels of society, there is a worldwide growth in popularity. The growing popularity of traditional medicine, termed the green boom, may be ascribed to people taking a more holistic approach to maintain their health. Traditional medicine is widely used on a regular basis by 70% of South Africans. Various indigenous medicinal plants are used for the preparation of traditional herbal medicine. These plants are mostly indigenous to the regions were it is used. In this study four medicinal plants (Bulbine frutescens, Leonotis leounurus, Melianthus major & Zantedecshia aethiopica) that are traditionally used in the Eastern Cape region for treating burn wound infections, were collected for investigation. The in vitro antibacterial activity of these plants was tested against different bacterial strains of eight different bacteria. The bacteria used in this investigation included bacterial strains of four Gram-positive bacteria, S. aureus, methicillin-resistant S. aureus (MRSA), E. feacalis, S. pyogenes and four Gramnegative bacteria, P. aeruginosa, A. baumanii, K. pneumoniae and P. mirabilis. Traditional preparations as well as three different extracts (methanol, aqueous & acetone) of the plants were used for in vitro antibacterial activity testing. The microtitre plate assay and agar dilution assay were used for determining the antibacterial activity of the traditional preparations and plant extracts against the different bacterial strains. In the microtitre plate assay the antibacterial activity was tested using the bacterial growth indicator, INT and a microtitre plate spectrophotometer to determine the minimal inhibitory concentrations of the plant extracts and traditional preparations. The microtitre plate assay was used for testing the antibacterial activity of the plants against the bacterial strains of five bacteria, S. aureus, MRSA, P. aeruginosa, A. baumanii and K. pneumoniae. The bacterial strains of the three bacteria, S. pyogenes, E. feacalis and P. mirabilis were not compatible with the microtitre plate assay using INT and spectrophotometric readings to determine bacterial inhibition. Therefore the agar dilution assay were used as an alternative method for determining the MIC’s of the plant extracts against the bacterial strains of these bacteria. The initial plant extract concentration in the microtitre plate assay differed with the different plant extracts in the microtitre plate assay. Acetone followed by methanol extracted the highest plant extract concentrations with the different medicinal plants. M. major followed by L. leonurus produced the highest plant extract concentrations following extraction with the different extraction solvents. Consequently the acetone extract of M. major had the highest plant extract concentration before serial dilution in the microtitre plate assay. Uniform plant extract concentrations were tested in the agar dilution assay. The methanol extract followed by the acetone extract of the plants gave the highest antibacterial activity against the different bacterial strains. The extracts of M. major followed by L. leonurus inhibited the highest number of bacterial strains in the microtitre plate assay and the extracts of B. frutescens inhibited the lowest number of bacterial strains. The acetone and methanol extracts of M. major were the only extracts that displayed antibacterial activity in the agar dilution assay. The bacterial strains of P. mirabilis were the only bacteria that were inhibited using this method. The bacterial strains of S. pyogenes and E. feacalis were not inhibited at any of the plant extract concentrations in the agar dilution assay.
142

Isolation of bioactive metabolites with activity against HIV-1 target proteins from extracts of Sutherlandia frutescens and Lobostemon trigonus

Dambuza, Ntokozo Shirley January 2007 (has links)
Acquired Immunodeficiency Syndrome (AIDS) is a human disease caused by the human immunodeficiency virus type 1 (HIV-1) and it is one of the biggest social, economic and health challenges in the world. The Joint United Nations Programme on HIV/AIDS (UNAIDS) and World Health Organization (WHO) estimated that between 33.4 to 46.0 million people around the world were living with HIV/AIDS in December 2005 and the highest estimates are in the Sub-Saharan Africa (around 25 million). In more developed countries a combined antiretroviral therapy called highly active antiretroviral therapy (HAART) is used, which results in reduced progression to AIDS in most patients. Despite the beneficial effects of HAART, significant side effects are experienced by treated patients. In addition, most infected people live in countries where the treatment is very expensive or, in many cases, not available at all. These people therefore rely on medicinal plants for health care. In this study, aqueous extracts from Sutherlandia frutescens and Lobostemon trigonus were screened for potential anti-HIV activities in a series of in vitro enzymatic assays, including reverse transcriptase, HIV-1 protease and glycohydrolases. Two extracts of Sutherlandia leaves (SFL-1 and SFL-2) were prepared that inhibited HIV reverse transcriptase and a Lobostemon leaf extract (LTL) was shown to also inhibit this enzyme. All extracts were assayed at 1.25mg/ml. Tannin content was determined for all active extracts using a tannic acid assay. SFL-1 and SFL-2 were found to contain about 6 percent and 7 percent tannins, respectively, and LTL contained 31% tannins by weight. Tannins were removed using polyamide columns and three fractions were collected for each. The extracts were also fractionated with Sephadex G-25, Amberlite IR 120 and Dowex 1-X8 as size exclusion, cation exchange and anion exchange, respectively. Extracts were also fractionated by preparative thin layer chromatography where two compounds were separated from S. frutescens extract with high activity against reverse transcriptase while showing insignificant inhibition towards other enzymes tested. SFL-BFW-10 and SFL-WEF-7 inhibited reverse transcriptase by almost 100 percent and the IC50 values calculated for these compounds were 0.34 and 0.23mg/ml, respectively. Cytotoxicity of these compounds was evaluated on Chang liver cells and peripheral blood mononuclear cells (PBMCs). None of these compounds showed any significant inhibition of cell proliferation. The purity of these compounds could not be confirmed because there was insufficient material to use in the techniques required to show purity and identification. Therefore, TLC was used to determine the nature of these compounds. SFL-BFW-10 was identified as an organic acid and SFL-WEF-7 was identified as flavonoid.
143

Production of biologically active recombinant HIV-1 protease and intehrase for the purpose of screening medicianl plant extracts

Bosch, Janine January 2009 (has links)
Human immunodeficiency virus (HIV) and its gradual weakening of the immune system is an ever growing threat. Acquired immune deficiency syndrome (AIDS), the final stage of HIV, renders a person vulnerable to various opportunistic infections, which in the end lead to death. Apart from intensive vaccine studies, treatment research mainly focuses on preventing the individual HIV enzymes (reverse transcriptase, integrase and protease) from performing their functions. Entry inhibitors, however, block viral entry into the cell, while antisense drugs lock onto the viral genome to keep it from functioning. In this study production of active recombinant HIV-1 protease and integrase was attempted for future drug screening programs. HIV-1 protease was cloned into a pET28b(+) vector and expressed in ROSETTA(DE3)pLysS cells. The protein was purified using a nickel-affinity column utilizing the hexa-histidine tag encoded by the vector. Gel filtration chromatography was attempted after refolding of the protease, but protease yield seemed to decrease with the additional purification step. Partially purified protease was characterized with kinetic studies. Kinetic parameters of HIV-1 protease were determined to be Km = 592 μM, Vmax = 0.59 μM/min and kcat = 31 s-1. HIV-1 integrase, which was cloned into a pET15b vector, was expressed in E. coli BL21(DE3) cells. The coding sequence had been mutated to introduce the amino acid substitutions F185K and C280S, increasing solubility of the protein. The first step in purification of this protein was nickel-affinity chromatography, after which cation exchange chromatography was attempted. HIV-1 integrase concentration was low throughout experiments and no clear elution from the cation exchange column could be observed. A non-radioactive enzyme linked HIV-1 integrase assay failed to detect integrase activity. Modifications to future studies of the integrase are suggested in the chapter involved.
144

Evaluation of plant extracts : artemisia afra and annona muricata for inhibitory activities against mycobacterium tuberculosis and human immunodeficiency virus

Pruissen, Megan Colleen January 2013 (has links)
Mycobacterium tuberculosis and Human Immuno-Deficiency Virus (HIV) have a high prevalence in South Africa. The development and spread of drug resistant tuberculosis is a serious problem which is exacerbated by tuberculosis (TB) co-infection in HIV patients. Traditional medicinal plants like Annona muricata and Artemisia afra are used for respiratory ailments and antiviral therapies respectively. The aim of this study was to evaluate Annona muricata (ethanolic extract) and Artemisia afra (ethanolic and aqueous extracts) for inhibitory activities against M. tuberculosis and HIV. In vitro bioassays for anti-TB activity included: microplate alamar blue assay (MABA), flow cytometry and ρ-iodonitrotetrazolium chloride assays while anti-HIV activity was determined using an HIV-1 reverse transcriptase colorimetric ELISA kit and an HIV-1 integrase colorimetric immunoassay. Cytotoxicity of plant extracts were assessed by the MTT assay on Chang Liver and HepG2 cells. Potential synergistic effects were determined using the basis of Combination Index. Potential interactions of plant extracts with drug metabolic pathways were evaluated with the Glutathione-S-Transferase assay kit as well as the CYP3A4 assay kit. A. muricata ethanolic extract exhibited anti-TB activity with MIC 125 μg/mL. MABA was shown to be the most sensitive and effective method for the detection of anti-TB activity. Artemisia afra aqueous extract showed HIV-1 reverse transcriptase inhibition exhibiting ˃85 percent inhibition at 1 mg/mL while the ethanolic extracts of A. afra and A. muricata showed inhibition of HIV-1 integrase activity at ˃86.8 percent and ˃88.54 percent respectively at concentrations >0.5 - 4 mg/mL. The aqueous extract of A. afra displayed inhibition of HIV-1 integrase ˃52.16 percent at 0.5 mg/mL increasing to 72.89 percent at 4 mg/ml of the extract. A. muricata was cytotoxic at an IC50 of 30 μg/mL and 77 μg/mL on Chang Liver and HepG2 cells respectively, whilst A. afra aqueous and ethanol extracts were not cytotoxic to both cell lines. The ethanolic extract of A. muricata showed both antagonistic and synergistic properties at various IC values, when used in conjunction with rifampicin. A. afra ethanolic extract interrupted GST activity while aqueous extracts of A. afra and A. muricata had a slight effect. All extracts interrupted CYP3A4 activity, however the ethanolic extracts of A. muricata and A. afra showed greater inhibition than the aqueous extract of A. afra. These extracts should be investigated further as they could be an important source of compounds for treatment of M. tuberculosis and HIV respectively.
145

An investigation into the antimicrobial and anticancer activities of Geranium incanum, Artemisia afra and Artemisia absinthium

Freidberg, Ryno January 2009 (has links)
It has been estimated that between 3000 and 4000 plant species are used for their medicinal properties throughout South Africa, with approximately 27 million South Africans making use of traditional medicines. Of this 27 million, 3 million South Africans rely on traditional medicine as their primary source of health care. Of the 250 000 to 500 000 known plant species, very few have been investigated for their pharmacological qualities, and compounds of significant medicinal value may still remain undiscovered in many plant species. The aims of this study included investigating the antimicrobial properties of Geranium incanum and Artemisia afra, both plants traditionally used for their medicinal properties, and comparing the antimicrobial activity of the latter to that of Artemisia absinthium, as well as investigating the anticancer properties of G. incanum and A. afra, and comparing the anticancer activity of the latter to that of A. absinthium. Infusions, aqueous-, methanol- and acetone extracts of the three plants were prepared and used for anticancer and antimicrobial screening. Plant specimens used to prepare extracts for antimicrobial activity were collected and extracted over three seasons, while extracts used for anticancer screening were prepared from plants collected during the summer only. Considerable variation existed in the percentage crude extract yields obtained when different extractants were used, while the season in which the plants were harvested and extracted also appeared to play a significant role in the amount of extract obtained. The plant extracts were screened for antimicrobial activity against various strains of Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus and Bacillus cereus, using an agar dilution method. G. incanum and A. afra possessed activity for C. albicans, while all three plants showed activity for S. aureus and B. cereus. Activity was largely dependent on the extraction method used. iii The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay was used to screen for anticancer activity of the respective extracts, at varying concentrations, against MCF-7 (human breast adenocarcinoma) cells, HT-29 (human colonic adenocarcinoma) cells and HeLa (human cervical cancer) cells. All of the extracts showed cytotoxic activity in all three cell lines to varying extents, depending on the extract used and cell line screened. The acetone extract of A. afra proved to be the most effective inhibitor with the lowest IC50 (2.65 ± 1.05 μg/ml) having been shown in MCF-7 cells. A. afra and A. absinthium showed similar inhibitory patterns, with the methanol- and acetone extracts having been the most potent inhibitors of each of the respective cell lines in general. Fluorescence microscopy employing 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) and propidium iodide (PI) staining indicated that the acetone extract of A. afra induces apoptosis in MCF-7 cells as apposed to necrosis, and the results were comparable to those obtained for cells exposed to cisplatin. Screening of the A. afra acetone extract for toxicity in normal human cells using the CellTiter-Blue® assay indicated the extract to be toxic to peripheral blood mononuclear cells (PBMC’s) at concentrations comparable to that for MCF-7 cells, while cell cycle analysis of MCF-7 cells exposed to the A. afra acetone extract indicated the extract’s ability to induce apoptosis comparable to that of cisplatin, with the extract exerting its activity at a point during or just prior to the S phase of the cell cycle.
146

The effect of OsteoEze Gold™ on the inflammatory marker CRP and quality of life in osteoarthritis of the knee

Levy, Romy 13 October 2014 (has links)
M.Tech. (Homoeopathy) / Osteoarthritis (OA) is a chronic and debilitating condition, characterized by irreversible damage to the joint space, most commonly affecting the knees, hips, hands and spine (Colledge et al., 2010). OA is the leading cause of joint pain and disability in middle-aged and elderly persons (Long et al., 2001). The prevalence of OA of the knee in adults living in the United Sates has grown from a reported 21 million in 1990 to a total estimate of 26.9 million in 2005 (CDC, 2011). By the age of 65 years, 80% of the total population has been reported as showing radiographic evidence of OA; while a 20-30% of the total population is symptomatic with radiographic evidence of OA (Doherty et al., 2006). Conventional treatment for OA of the knee is aimed at pain management by use of analgesics and non-steroidal anti-inflammatory drugs (NSAIDs). Some negative effects of these drugs include drug dependency, liver and kidney damage, cardiovascular pathologies, gastric upset and depression. Corticosteroid injections are also used to alleviate chronic inflammation and joint pain, but may lead to further joint destruction (Shamoon and Hochberg, 2000; Mayo Foundation for Medical Education and Research, 2011). OsteoEze Gold™ is a nutraceutical product that contains chondroitin sulphate, glucosamine sulphate, vitamin C and manganese. In combination, the constituents of OsteoEze Gold™ have been shown to be useful in the treatment for OA of the knee (Clegg et al., 2006). In addition, studies have shown that these ingredients prove effective in reducing moderate to severe pain in sufferers of OA of the knee (Vidyasagar et al., 2004). The aim of this study was to determine the effect of OsteoEze Gold™ on the inflammatory marker C-reactive protein (CRP) and quality of life in OA of the knee using blood tests and the Arthritic Impact Measurement Scales (AIMS2SF) respectively. This was a 16-week, double blind, placebo-controlled study using matched pairs according to age, gender and severity of symptoms, and formed part of a group study, with another researcher, who utilized the Intermittent and Constant Osteoarthritis Pain scale (ICOAP) Short Physical Performance Battery (SPPB) and the same sample...
147

The efficacy of chiropractic care in the treatment of plantar fasciitis utilising foot and ankle manipulation, gastrocsoleus stretching and cross friction massage of the plantar fascia

Rama, Sunil 04 June 2012 (has links)
M. Tech. / Plantar fasciitis is the most common cause of heel pain for which professional care is sought (Singh, 2008). Plantar fasciitis is a common injury, and one which is known to be stubborn to many forms of treatment. The aim of the study was to determine the most effective treatment for individuals suffering with plantar fasciitis comparing three protocols, i.e. mobilisation and manipulation of the foot and ankle with cross friction massage of the plantar fascia versus stretching of the gastroc-soleus complex with cross friction massage of the plantar fascia or a combination of the aforementioned treatments. Participants in the study were recruited from information pamphlets, the University of Johannesburg Chiropractic and Podiatry Day Clinics and running clubs. Only those participants that conformed to the selection criteria were allowed to participate in the study. A total of forty five participants were included. These participants were randomly placed into one of three groups of fifteen participants in each group. Group one received manipulation and mobilisation therapy to the foot and ankle with cross friction massage of the plantar fascia. Group two received cross friction massage of the plantar fascia and stretching of the gastroc-soleus muscle. Group three received a combination of the aforementioned therapies. Subjective data was collected using the Short Form McGill Pain Questionnaire (SF-MPQ) and the Foot Function Index (FFI). Objective data was collected using the algometer to test differences in pain at the plantar fascia as well as ankle range of motion in dorsiflexion and plantarflexion which was measured using a goniometer. The results of this study indicate that cross friction massage of the plantar fascia and stretching of the gastroc-soleus complex would appear to have shown the greatest overall improvement in terms of reducing the pain and disability and ankle dorsiflexion range of motion. Manipulation of the foot and ankle, cross friction massage of the plantar fascia and stretching of the gastroc-soleus complex proved to have shown the greatest overall improvement in plantarflexion only. Based on the results of the study, cross friction massage and gastroc-soleus stretching is the most effective treatment protocol for plantar fasciitis.
148

Factors contributing to non-adherence of patients to highly active antiretroviral treatment at Kanyamazane Clinic, Ehlanzeni District, Mpumalanga Province

Mahlalela, Maria Sizakele January 2014 (has links)
Thesis (M.CUR.) --University of Limpopo, 2014. / Background: The national HAART programme in South Africa was launched in April 2004. Highly Active Antiretroviral Therapy (HAART) is the medication that slows down the progression from HIV to AIDS, while it had been introduced in Western countries in 1996. Adherence to ART is the major factor in ensuring the virologic success of an initial regimen and is a significant determinant of survival for HIV-infected patients with the wild type virus who are on highly active antiretroviral treatment. Patients with suboptimal adherence are at risk, not only of HIV progression but also of the development of drug resistance and consequent narrowing of options for future treatment. Sub-Saharan Africa carries the highest burden of HIV infections and HIV / AIDS related mortality in the world. South Africa is reported to have the largest population living with the HIV infection. Aims: The aim of the study was to explore factors that contributed to non- adherence of patients to HAART at the Kanyamazane Clinic, Ehlanzeni District, Mpumalanga Province. Study method: A qualitative, exploratory, descriptive, and contextual research design was used for this study. A non-probability purposive sampling method was used to select participants ranging from 15 to 60 years of age and who were on HAART for more than one year. Fifteen participants were selected and the sample size was determined by data saturation. Semi-structured interviews were conducted to collect data through the use of an interview guide on their structured follow-up dates and audio recordings of the interviews were made. Data was analysed following the Tesch’s method. Themes and sub-themes were developed. Results: Findings indicate that factors contributing to non-adherence of patients to HAART are the patient-provider relationship and delivery of services, waiting hours and overcrowding, working hours of the facility, forgetfulness and experiencing better health, belief systems, side-effects, pill burden, migration due to employment, poverty and unemployment, as well as disclosure, stigma, and discrimination. Conclusion and recommendations: The study recommends that HAART services should be provided every day, including on weekends, to improve access and to reduce waiting times; and economic empowerment through skills acquisition programmes to participants and provision of jobs to earn a living. Keywords: Non-adherence, highly active antiretroviral treatment, regimen, drug resistance.
149

Proteomics analysis of anti-cancer effects of gynostemma pentaphyllum saponins in Apc min/+ colorectal cancer mouse model

Wong, Wing Yan 01 January 2012 (has links)
No description available.
150

Treatment of neuropathic pain : by Chinese scorpion (Buthus martensii Karsch)

Wong, Shing Chau 01 January 2011 (has links)
No description available.

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