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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.
41

Male circumcision as HIV/Aids prevention strategy in South Africa

Tsimane, Salathiel 23 June 2014 (has links)
M.A. (Public Management and Governance) / This study starts with an introduction and background, and this is followed by a statement of the research problem, research rationale, research objectives, research design, research methodology and the data collection methods. A list of acronyms will be provided, as well as an overview of chapters, conclusions, and acknowledgements. “Around 5.7 million in 2009 had contracted HIV and AIDS and in the preceding year 250,000 South Africans died due to HIV/AIDS related diseases. All age categories and gender are prone to contracting the disease and the resultant loss of life has had a devastating effect on the workforce. Death due to this disease has caused loss of income and family disintegration” (Sottile 2013:2). In 2010, some 280,000 South Africans died of HIV/AIDS. In the decade up to 2010, between 42% and 47% of all deaths among South Africans were HIV/AIDS-related deaths (Sottile 2013:2). Mlambo et al (2011:1) further say that “The Human Sciences Research Council estimates that 10.9% of all South Africans have HIV/AIDS. Additionally, the Central Intelligence Agency estimates that 310,000 individuals died in South Africa from HIV/AIDS in the year 2009”. A study in 2003 made a comparison on two scenarios, an HIV/AIDS scenario and a no-HIV/AIDS scenario and this was based on the annual growth rates between 2002 and 2015. The finding was that “real growth in GDP would be 0.6% lower than if there were no HIV/AIDS, but per-capita growth in GDP would be 0.9% higher. Growth in population would have been 1.5% lower, and growth of the labour force would be 1.2% lower, but the unemployment rate would be 0.9% lower as well” (Avert.Org 2010:2). Different HIV/AIDS prevention strategies are being implemented in South Africa. The focus in this study is on male medical circumcision (hereafter MMC), which is the removal of all or part of the foreskin on the penis. It can either be performed surgically in hospitals or at initiation schools. Initiation schools perform the procedure as a traditional rite of passage from boyhood to manhood, and this is referred to as traditional male circumcision (TMC). This practice has up till now been performed purely for traditional or religious purposes, but it can no longer be viewed only as such. It should, instead, also be seen as a measure to curb the spread of the HIV/AIDS pandemic. A number of observational studies (which will be referenced later) found that circumcised men had smaller chances of contracting HIV infection compared with uncircumcised men...
42

Adherence and non-adherence to antiretroviral treatment in HIV people in Port Elizabeth

Masokoane, Kgomotso Quentinne January 2009 (has links)
The introduction of antiretroviral drugs (ARVs) in 1996 transformed the treatment of HIV and AIDS, improving the quality and greatly prolonging the lives of many infected people. HIV (Human Immunodeficiency Virus) is the virus that is believed to cause AIDS. AIDS (Acquired Immune Deficiency Syndrome) is the collection of illnesses or symptoms that ultimately results in death. Antiretroviral (ARVs) drugs or Highly Active Antiretroviral Therapy (HAART) is the treatment that has been applied to combat the HI virus in a bid to slow down the progression of AIDS and ultimately prolong the life of the infected individual. The study aimed to explore and describe the factors contributing to adherence and non-adherence to ARVs in individuals on treatment. A sample of 81 individuals who have been on ARV and HAART treatment for six months or more was used. The methodology used was exploratory-descriptive and the data obtained was quantitative in nature. A biographical questionnaire and questionnaire with questions aimed at ascertaining the possible factors that contribute to individuals either adhering to or defaulting on their treatment, such as side effects and cost of treatment, was administered. The data obtained was analysed by means of descriptive statistics and frequency counts. The results of the study showed that the sample had a fairly high level of adherence. The factors that could undermine adherence were identified as lack of support, as familial and health provider support acts as a motivator to adhere; substance abuse as it can lead to forgetting to take treatment; unemployment and poverty, as these can lead to an inability to return for follow up clinic visits or failure to have food to take with the pills; and the type of treatment regimen whereby the more complex the treatment is the more likely it is that adherence will be difficult to maintain. Suggestions were made as to future research involving antiretroviral therapy (ART). Finally the limitations as well as the value of the research were outlined.
43

The design and synthesis of novel HIV-1 protease inhibitors

Tukulula, Matshawandile January 2009 (has links)
This study has focused on the synthesis of truncated analogues of the hydroxyethylene dipeptide isosteres, such as Ritonavir®, currently in clinical use as HIV-1 protease inhibitors. The reactions of pyridine-2- and quinoline-2-carbaldehydes with methyl acrylate, in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) or 3- hydroxyquinuclidine (3-HQ) as nucleophilic catalysts, have afforded a series of Baylis- Hillman adducts, acetylation and cyclisation of which have provided access to a series of indolizine-2-carboxylate esters. The carboxylic acids, obtained by base-catalyzed hydrolysis of these esters, have been coupled with various protected (and unprotected) amino compounds using the peptide coupling agent, 1,1’-carbonyldiimidazole (CDI), to afford a series of indolizine-2-carboxamides as indolizine-based truncated Ritonavir® analogues in quantitative yield. Aza-Michael reactions of pyridine-3-carbaldehydederived Baylis-Hillman adducts with various amino compounds have provided access to a range of pyridine-based products as mixtures of diastereomeric aza-Michael products. The assignment of the relative stereochemistry of the aza-Michael products has been established using 1-D and 2-NOESY experiments and computer modelling techniques. Computer modelling studies have also been conducted on selected aza-Michael products using ACCELRYS Cerius2 software, followed by interactive docking into the HIV-1 protease receptor site, using AUTODOCK 4.0. The docking studies have revealed hydrogen-bonding interactions between the enzyme and the synthetic ligands. Saturation Transfer Difference (STD) NMR experiments have also indicated binding of some of the aza-Michael products to the HIV-1 protease subtype C enzyme, thus indicating their binding and possible inhibitory potential.
44

Studies towards the development of novel HIV-1 integrase inhibitors

Lee, Yi-Chen January 2010 (has links)
The project has focused on the preparation of several series of compounds designed as potential HIV-1 integrase inhibitors. Various 2-nitrobenzaldehydes have been reacted with two activated alkenes, methyl vinyl ketone (MVK) and methyl acrylate, under Baylis-Hillman conditions to afford α-methylene-β-hydroxylalkyl derivatives in moderate to excellent yields. The reactions were conducted using the tertiary amine catalysts, 1,4-diazabicyclo[2.2.2]octane(DABCO) or 3-hydroxyquinuclidine (3-HQ) with chloroform as solvent, and yields were optimised by varying the catalyst, reagent concentrations and the reaction time. Reductive cyclization of the Baylis-Hillman adducts via catalytic hydrogenation, using 10% palladiumon-carbon catalyst in ethanol, afforded quinoline and quinoline N-oxide derivatives. In some cases “acyclic” reduction products were also isolated. Reaction of the Baylis-Hillman MVK adducts with HCl, has resulted in effective nucleophilic (SN’) displacement of the hydroxyl group to afford allylic chloride derivatives. Direct substitution of these chloro derivatives by secondary or primary amines, followed by catalytic hydrogenation gave quinoline derivatives containing a 3-aminomethyl substituent. The Baylis-Hillman ester adducts obtained from reaction with methyl acrylate were treated directly with various amines to give diastereomeric conjugate addition products. Reactions with piperazine gave N,N’-disubstituted piperazine products. The piperidine derivatives have been dehydrated to give cinnamate esters in moderate yields. The products, which have all been satisfactorily characterised by elemental (HRMS) and spectroscopic (1- and 2-D NMR) analysis, constitute a “library” of compounds for in silico and in vitro studies as potential HIV integrase inhibitors.
45

Neuroprotective mechanisms of nevirapine and efavirenz in a model of neurodegeneration

Zheve, Georgina Teurai January 2008 (has links)
AIDS Dementia Complex (ADC) is a neurodegenerative disorder implicated in HIV-1 infection that is associated with elevated levels of the neurotoxin, quinolinic acid (QA) which causes a cascade of events to occur, leading to the production of reactive oxygen species (ROS), these being ultimately responsible for oxidative neurotoxicity. In clinical studies, Non-nucleoside reverse transcriptase inhibitors (NNRTIs), efavirenz (EFV) and nevirapine (NVP) have been shown to potentially delay the progressive degeneration of neurons, thus reducing the frequency and neurological deficits associated with ADC. Despite these neuroprotective implications, there is still no biochemical data to demonstrate the mechanisms through which these agents offer neuroprotection. The present study aims to elucidate and further characterize the possible antioxidant and neuroprotective mechanisms of NVP and EFV in vitro and in vivo, using QA-induced neurotoxicity as a model. Research has demonstrated that antioxidants and metal chelators have the ability to offer neuroprotection against free radical induced injury and may be beneficial in the prevention or treatment of neurodegeneration. Hence the antioxidant and metal binding properties of these agents were investigated respectively. Inorganic studies, including the 1, 1-diphenyl-2 picrylhydrazyl (DPPH) assay, show that these agents readily scavenge free radicals in vitro, thus postulating the antioxidant property of these agents. The enhancement of superoxide radical generation and iron mediated Fenton reaction by QA is related to lipid peroxidation in biological systems, the extent of which was assayed using the nitroblue tetrazolium and thiobarbituric acid method respectively. Both agents significantly curtail QA-induced lipid peroxidation and potentially scavenge superoxide anions generated by cyanide in vitro. Furthermore, in vivo results demonstrate the ability of NVP and EFV to protect hippocampal neurons against lipid peroxidation induced by QA and superoxide radicals generated as a consequence thereof. The alleviation of QA-induced oxidative stress in vitro possibly occurs through the binding of iron (II) and / or iron (III), and this argument is further strengthened by the ability of EFV and not NVP to reduce iron (II)-induced lipid peroxidation in vitro directly. In addition the ferrozine and electrochemistry assay were used to measure the extent of iron (II) Fe[superscript 2+] and iron (III) Fe[superscript 3+] chelation activity. Both assays demonstrate that these agents bind iron (II) and iron (III), and prevent redox recycling of iron and subsequent complexation of Fe[superscript 2+] with QA which enhances neuronal damage. Both NNRTIs inhibit the endogenous biosynthesis of QA by inhibiting liver tryptophan 2, 3-dioxygenase activity in vivo and subsequently increasing hippocampal serotonin levels. Furthermore, these agents reduce the turnover of hippocampal serotonin to 5-hydroxyindole acetic acid. NVP and not EFV increase 5-hydroxyindole acetic acid and norepinephrine levels in the hippocampus. The results of the pineal indole metabolism study show that NVP increases the synthesis of melatonin, but decreases N-acetylserotonin, 5-hydroxyindole acetic acid and 5-hydroxytryptophol levels. Furthermore, it shows that EFV decreases 5-hydroxyindole acetic acid and melatonin synthesis. Behavioural studies using a Morris water maze show that the post-treatment of rats with NVP and EFV significantly improves QA-induced spatial memory deficits in the hippocampus. This study therefore provides novel information regarding the neuroprotective mechanisms of NVP and EFV. These findings strengthen the argument that these NNRTIs not only have antiviral effects but possess potential neuroprotective properties, which may contribute to the effectiveness of these drugs in the treatment of ADC.
46

Isolation and evolution of novel nucleoside phosphorylases

Visser, Daniel Finsch January 2010 (has links)
Approximately 33.4 million people are living with HIV/AIDS. Of those, 97% live in low and middle income countries, with 22.4 million in sub-Saharan Africa. Only 42% of the people who require anti-retrovirals (ARVs) in low to middle income countries are receiving anti-retroviral therapy (ART). There is a need to develop novel and cost effective methods for producing antiretroviral drugs. Stavudine and azidothymidine (AZT) were identified as potential targets because they could both be produced through a common intermediate – 5 methyluridine (5-MU). It has been established that the biocatalytic production of 5-methyluridine is possible through a reaction known as transglycosylation, in a process which has not previously been demonstrated as commercially viable. A selection of biocatalysts were expressed either in recombinant E. coli strains or in the wild type organisms, purified and then screened for their ability to produce 5-MU. A combination of Bacillus halodurans purine nucleoside phosphorylase 1 (BHPNP1) and E. coli uridine phosphorylase (EcUP) gave the highest 5-MU yield (80%). This result represents the first combination of free enzymes from different organisms, giving high yields of 5-MU under high substrate conditions. Both enzymes were purified and successfully characterised. The established pH optimum was pH 7.0 for both enzymes. Temperature optima and stability data for BHPNP1 (70 C and t1/2 at 60 C of 20.8 h) indicated that the biocatalytic step was operating within the capabilities of this enzyme and would operate well at elevated temperatures (up to 60 C). Conversely, the temperature optimum and stability data for EcUP (optimum of 40 C and t1/2 at 60 C of 9.9 h) indicated that the enzyme remained active at 40 C for the duration of a 25 h biotransformation, but at 60 C would only be operating at 20% of its optimum activity and would lose activity rapidly. BHPNP1 and EcUP were used in a bench scale (650 ml) transglycosylation for the production of 5-MU. A 5-MU yield of 79.1% was obtained at this scale with a reactor productivity of 1.37 g.l-1.h-1. Iterative saturation mutagenesis was used to rapidly evolve EcUP for improved thermostability. A moderately high throughput colorimetric method was developed for screening the mutants based on the release of p-nitrophenol upon phosphorolysis of a pyrimidine nucleoside analogue. By screening under 20 000 clones the mutant UPL8 was isolated. The mutant enzyme showed an optimum temperature of 60 C and improved stability at 60 C (t1/2 = 17.3 h). The increase in stability of UPL8 is due to only 2 mutations (Lys235Arg, Gln236Ala). These mutations may have caused an increase in stability due to interactions with other structural units in the protein, stabilization of the entrance to the binding pocket, or by decreasing the flexibility of the α-helix at the N-terminus. Transglycosylation experiments showed that the mutant enzyme UPL8 is a superior catalyst for the production of 5-MU. A 300% increase in reactor productivity was noted when free enzyme preparations of UPL8 was combined with BHPNP1 at 1.5% m.m-1 substrate loading. The high yield of 5-MU (75-80% mol.mol-1) was maintained at 9% m.m-1 substrate loading. A commercially viable productivity of 31 g.l-1.h-1 was thus realised. Further optimisation of the process could produce still higher productivities. Future work in directed evolution of nucleoside phosphorylases is envisaged for improved stability and enhanced substrate range for application to other commercially relevant transglycosylation reactions.
47

Rural livelihoods and adherence to HIV and AIDS antiretroviral therapy in Chivanhu Settlement, Nemamwa Village in Masvingo District, Zimbabwe

Wapinduka, Tendai January 2013 (has links)
The Human Immunodeficiency Virus (HIV) and Acquired Immuno Deficiency Syndrome (AIDS) epidemic has had massive detrimental impacts on rural communities across Africa including in Zimbabwe. In response to the HIV and AIDS epidemic, the government of Zimbabwe has developed and adopted comprehensive programmes to address HIV and AIDS prevention, care and support. One of the critical components of these programmes relates specifically to treatment of the HIV infected given that HIV and AIDS is increasingly seen as a manageable threatening disease. However the success and effectiveness of the treatment regimen (involving antiretroviral drugs or ARVs) is dependent heavily on complete adherence to the rigid and complex regimens. It is against this background that this thesis studies a particular rural community in Zimbabwe called Chivanhu (in Masvingo Province) in terms of the relationship between rural livelihoods and HIV and AIDS (particularly HIV treatment and treatment adherence). Unlike other rural communities (notably in communal areas), Chivanhu is an informal and unstable community with a turbulent history. Most rural studies of HIV and AIDS in Zimbabwe and elsewhere in the region have focused on well-established and stable communities in which agricultural production is still of some significance. In such communities, the impact of HIV and AIDS on livelihoods is severe but, in more informal settlements, the vulnerability of households to the epidemic (and challenges pertaining to treatment adherence) is even more pronounced. Using a rural livelihoods framework, this thesis seeks to identify, understand and analyse the conditions which shape levels of adherence to HIV and AIDS in the informalsettlement of Chivanhu in Zimbabwe.
48

Evaluation of the efficacy of Carpobrotus edulis (L.) bolus leaf as a traditional treatment for the management of HIV/AIDS

Omoruyi, Beauty Etinosa January 2014 (has links)
The human immunodeficiency virus (HIV) is one of the most common and dreaded diseases of the 21th century. Today, the disease is still spreading with increasing incidence. “Since the beginning of the epidemic, almost 75 million people have been infected with the HIV virus and about 36 million people have died of HIV. Globally, 35.3 million [32.2–38.8 million] people were living with HIV at the end of 2012” (http://www.who.int/gho/hiv/en/). Several studies have been conducted on herbs under a multitude of ethnobotanical grounds. The use of medicinal plants for the management of HIV has become a common practice especially, in the Eastern Cape Province of South Africa (Wilfred Otang Mbeng, 2013 PhD thesis, UFH). At the beginning of this programme, an ethnomedicinal survey of plants used for the management of HIV infection was carried out in targeted areas of the Province and information on the names of plants, the parts and the methods of preparation were collected. The survey revealed that 18 species representing 12 families were found to be commonly used for the management of HIV, as well as other opportunistic diseases such as tuberculosis, diabetes mellitus, sores, high blood pressure, etc. Carpobrotus edulis was selected for this research because it was the most frequently used in the Province. The foliar micro morphological contents of the plant, its phytochemical and antioxidant activity, in vitro antimicrobial activity, inhibitory effect against HIV-1 protease and reverse transcriptase, mechanisms of action and cytotoxicity were investigated. In terms of the foliar micro morphological contents in plants, an electron microscopy scanning (SEM) was completed. Investigation revealed that both glandular tricomes and calcium oxalate crystals (CaOX) were observed. Consequently, it is hypothesized that the bioactive therapeutic compounds secreted by C. edulis may be produced in the glandular trichomes. An investigation of phytochemical content of the plant extracts (C. edulis) was completed using four solvent extracts (hexane, acetone, ethanol and water). Results of the phytochemical analysis showed that proanthocyanidins (86.9 ± 0.005%) where highest in the aqueous extract with phenolics at 55.7 ± 0.404% in acetone extract, tannin at 48.9 ± 0.28% in ethanol extract, while the hexane extract had the highest levels of flavonoids (0.12 ± 0.05%) and flavonols (0.12 ± 0.05%). Antioxidant studies of the various extracts revealed that aqueous and ethanol extracts were found to be the best solvents for antioxidant activity in C. edulis leaves. GC-MS analysis of the essential oil from C. edulis leaves revealed that the essential oil contained at least 28 compounds. These included, in order of abundance: Oxygenated monoterpenes (36.61%); fatty acids esters (19.25%); oxygenated diterpenes (19.24%); monoterpenes (10.6%); sesquiterpenes (3.58%); and diterpenes (1.43%). Similarly, a GC-MS analysis of the crude hexane, acetone and ethanol extracts from C. edulis leaves identified a total of 59 compounds. Of the 59 compounds, 12 major phyto-metabolites that are active against infectious diseases were identified. To comfirm the potential use of C. edulis to treat infectious disease, antifungal activity of the crude essential oil extract and the four solvent extracts were tested against Candida albicans, Candida krusei, Candida glabrata, Candida rugosa and Cryptococcus neoformans strains. The essential oil extract was found to be the most active against all the fungal strains tested and performed better than the four extracts used various solvents used to extract (hexane, acetone, ethanol and water) the C. edulis leaves were tested for antibacterial and anti HIV-1 reverse transcriptase (RT) activity. The results indicated that both gram-positive and gram-negative isolates were inhibited by the extracts (hexane, acetone and ethanol) but antimicrobial activity was observed for the water extract. The lowest minimum inhibitory concentration values were obtained for the ethanol extract, followed by acetone and hexane extracts. No inhibition of HIV-1 reverse transcriptase was observed for any of the leaf extracts, even up to concentrations of 16 mg/ml. The potential inhibitory activities of the various solvent extracts against HIV-1 protease were evaluated at four different concentrations (16, 1.6, 0.16 and 0.016 mg/ml). Results indicated that the water extract showed almost 100% inhibition of HIV-1 protease activity, with an IC50 of 0.86 mg/ml leaf extract. Other solvent extracts (hexane, acetone and ethanol) however, did not show any inhibition activity above that observed for the DMSO control. The metabolic components in the water extract were subjected to LC-MS/MS analysis, which identified at least 91 compounds present in the water extract. Further studies involving the molecular modelling need to be carried out to confirm the inhibitory potential of these compounds. The cytotoxicity of the water extract of C. edulis leaves was also screened using human Chang liver cells at concentrations ranging bewteen 0.005 mg/ml and 1 mg/ml. Results indicated that the water extracts were not toxic. In conclusion the results from this study support the use of water extracts of C. edulis leaves by traditional healers to treat HIV infections and have identified possible mechanisms of action of the water extracts of C. edulis.
49

A constructivist study of social work's involvement with HIV/AIDS

Hogan, Paula Jaye 01 January 1995 (has links)
No description available.
50

Exploring the interplay between HIV and AIDS treatment discourses and subjectivity in South Africa

Nkomo, Nkululeko January 2017 (has links)
A thesis submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Doctor of Philosophy, July, 2017 / This thesis explores the rearticulation of subjectivity in the context of the struggle for antiretroviral therapy in South Africa, and also in the contemporary era of treatment accessibility for HIV and AIDS. Two sub-aims are investigated: the first concerns exploring how, and with what consequences, subjectivity was deployed in the contestations that characterized the South African ‘AIDS war’; the second concerns inquiring into the intelligibility of subjectivity in public and everyday consciousness in the post-AIDS war period. Integrating qualitative analyses with the theoretical lens of an analytics of governmentality, the data set includes policy-related archival materials, a popular HIV advice column and interviews with people living with HIV and on antiretroviral therapy. The thesis brings into sharp focus the adumbration of the right to health with rational decision-making, dignity and autonomy. Much more than a way of organizing interests, advocating for the right to treatment - to prevent the transmission of HIV from mother to child and to slow-down HIV spread - was a strategy of effecting a rationality-cum-affective transfiguration of a widespread helplessness and despair into self-reliance and hope. At the level of public and everyday consciousness, self-government on antiretroviral therapy lies at the intersection of knowledge, self-care and self-management. However, such a subjective positionality is not adopted unproblematically, or even sustained indefinitely, owing to the relative weight of other disparate requirements upon oneself from day to day. What emerged out of the epic battle for antiretroviral therapy, undergirding the prevailing current public and policy orientation to antiretroviral therapy care, was the combination of an optimistic rationality and a hopeful affectivity for the potential of fashioning an HIV-positive subjectivity, contiguously responsibilized and self-responsibilizing. At the experiential level of living on ARVs, where autonomy is synonymous with self-regulation, the thesis demonstrates that self-responsibility is also an unpredictable and fluid undertaking of navigating the affective tumult of hopefulness, uncertainty, sacrifice and tension. / XL2018

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