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.

The Home and Community Based Care (HCBC) and Support programme has been established as a cost effective response for communities to tackle HIV and AIDS and many other chronic conditions and vulnerabilities which are faced by individuals, families and communities. In terms of the Framework for Home and Community Based Care and Support Programme (2012: 4) HCBCs create an enabling platform for “individuals, families and communities to have access to holistic and comprehensive services nearest to home, which encourages participations by people, responds to the needs of the people, encourages traditional community life and strengthens mutual support opportunity and social responsibility”. Victor Khanye Local Municipality, IDP (2010-2011: 116) states that VKLM is faced with: a high incidence of HIV and AIDS due to poverty, ignorance and a lack of proper entertainment facilities; shortage of clinics and professional staff members, which makes it difficult for patients to access treatment and maximum care and support; and an increase in the number of OVCs which results in a lack of parental care and guidance, poverty, illiteracy, lack of access to medical care, school drop-outs and ultimately an increase in criminal activity and the further spread of HIV and AIDS. The research will assess the effectiveness of Home Community Based Care programmes (HCBCs) on orphaned and vulnerable children with specific reference to the Victor Khanye sub-district in Nkangala District, Mpumalanga Province. The research was conducted in Delmas and its surrounding farming areas. Victor Khanye sub-District has nine wards, most of which are predominantly farming rural areas. The field research took place during June and August 2013 and represents observations recorded at the field interviews, the local AIDS committee and one-on-one interviews with beneficiaries The study is concluded with conclusions drawn from the field study and recommendations.

Background: Despite the prevalence of HIV/AIDS stabilizing and slightly decreasing in certain provinces, there are a number of People Living With HIV/AIDS (PLWHA) in South Africa. Many people seek help at primary health clinics and hospitals and receive chronic care at these facilities. Caring for these chronic patients and new patients entering the health system can be stressful to the health professionals who are involved. Many studies that have been conducted have focused on the clinical aspects of individual patients, while few studies have focused on the experiences and stressors of health professionals looking after PLWHA. To ensure quality of care for patients with HIV/AIDS, it is important to understand the experiences of health professionals looking after HIV/AIDS patients and how stressful experiences may influence their attitude towards these patients. Aim: The aim of this study is to report the factors health professionals perceive as occupational stressors caring for people living with HIV/AIDS in the public health sector of the Nelson Mandela Metropolitan Municipality. Research design and Methodology: A quantitative, descriptive and non-experimental research design was followed. A pilot study was conducted to determine the clarity of questions, effectiveness of the instructions, completeness of the response sets, the time required to complete the questionnaires and the success of the data collection. The primary method of data collection was self-administered questionnaires. The questionnaires were dispatched to 30 health professionals at the public health facilities in the Nelson Mandela Metropolitan Municipality. A descriptive statistical analysis was done using a Statistical Package. This revealed the following findings. Findings: The following are the findings that were perceived to be occupational stressors: organizational factors, job design factors, career and promotional factors, role-related factors and cultural factors. iv Conclusion and recommendations: There are occupational stressors that affect health care professionals working in an HIV/AIDS setting. The following are the recommendations to rectify or to improve the situation: • Improve the communication of goals and objectives; • Redesign the job; • Human-resources development ; • Improvement of salaries; • Career planning and mentoring; and • Sensitisation of employees to cultural differences.

M.A. / The researcher has undertaken a social constructionist research project that aims to explore the narratives of therapists who work with HIV-positive clients in the South African context. The researcher hoped to generate information regarding the: difficulties or challenges that are peculiar to this type of therapy and the impact of this therapy on the professional and personal lives of the therapist. The initial part of the dissertation covers an investigation of the literature regarding HIV/AIDS and HIV-related therapy. This literature reveals that mental health workers and psychologists experience considerable stress and 'burn-out' related to the many difficult issues provoked by HIV-positive clients. The theoretical foundations of postmodernism and social constructionist research are also described. In line with the researcher's epistemology, the methodology was qualitative in nature and made use of unstructured interviews. The narratives of the participants were then subjected to a qualitative or thematic analysis. The results of the study are presented in terms of the significant themes in the participants' accounts. It is evident in the narratives of the research participants that there are peculiar difficulties in therapy with HIV-positive clients. Also evident are the significant effects that this work has on the therapists' professional and personal beliefs, attitudes, philosophies and behaviour. Finally the results are discussed and a critical evaluation of the study is offered. The objective of the research is not to generalise the findings to all Clinical Psychologists who work with HIV-positive clients. A recommendation based on the findings is that therapists considering working with HIV-positive clients familiarise themselves with the issues that this therapy raises.

People living with HIV/AIDS (PLH) struggle with depression. Recent research suggests that depression affects medical regimen adherence, disease progression, and risky sexual behaviors. The present study uses a stress and coping theory viewing HIV-related stigma and physical symptoms as stressors in PLH. Results suggest whereas symptoms and stigma consistently predict negative affect, positive affect, and overall depression, the role of optimism, pessimism, active coping, denial, and behavioral disengagement is not as clear. Pessimism and denial predict negative affect and depression. Optimism and behavioral disengagement predict depression and positive affect. Active coping only predicts positive affect. Focusing on positive and negative affect as distinct components that contribute to overall depression may help researchers develop interventions more effectively.

AIDS-related stigma and mental health professionals.

The HIV/AIDS epidemic continues to grow and minorities have been affected at a disproportionate rate. Two factors that are hypothesized to be associated with HIV/AIDS stigma include ethnic identity and acculturation. The current study uses a diverse, gender-balanced sample (n= 201, aged 23-68) of African-Americans (54.2%), European Americans (31.8%), and Latinos/Hispanics (10%) to evaluate the relationship among the proposed variables. The study found that higher levels of ethnic identity and other group orientation were associated with lower levels of perceived HIV/AIDS stigma. A stepwise linear regression analysis (adjusted R2 = .13, F(11, 189) = 3.74, p < .001) revealed that as the level of inclusiveness of other ethnic groups (t = -4.263, p < .001) increases, the level of perceived HIV/AIDS stigma decreases. The results from this study suggest that the development of interventions that address stigma and inclusiveness of other ethnic groups may benefit people living with HIV/AIDS.

PhD / Department of Microbiology

Thesis (PhD. (Nursing Science)) --University of Limpopo, 2019 / The ability of professional nurses to support and motivate people living with HIV and AIDS to disclose to sexual partner continue to be a challenge based on the social, economic, psychological and ethical circumstances that surround the process to do so. A qualitative research study using semi-structured interviews with a schedule guide whereby probing questions were used to elicit more data. Two focus groups with 6 professional nurses were also conducted to explore and describe professional nurse’s knowledge and practices as they support People Living With HIV and AIDS (PLWHA) to disclose their positive status to sexual partners. The interviews were carried out in five (5) district hospitals of Limpopo Province, South Africa. Dickoff, James, and Wiedenbach (1968) practice theory guided the study. Study findings revealed that professional nurses do understand the concept but however it is difficult for them to translate and link learning and understanding in the clinical area. Social, economic, psychological and ethical dilemmas pose a challenge for professional nurses to support individuals to disclose to sexual partners. Professional nurses refer individuals with challenges to psychologists and social workers, but however, they do not receive referral back on the outcome. The absence of support groups and link with community-based groups to support PLHWA reduce efforts to improve knowledge on benefits of disclosure to communities led by PLHWA including reduction of stigma and discrimination associated with the diagnosis. The study therefore, recommends a training programme that links the South African Nursing Council statutes, including that of World Health Organization and Department of Health with teaching and learning methods that clarify and simulate real clinical situation to enhance the translation of this policy in the real-life situation. The training programme further suggests a link with community base structures led by PLWHA to enhance disclosure of HIV positive status to a sexual partner, reduction of stigma and discrimination associated with the diagnosis and reduce the incidence of HIV among people living with HIV. Key words: People living with HIV infection, Professional nurses, disclosure of HIV to sexual partners

Thesis (Ph. D. (Statistics)) -- University of Limpopo, 2019 / Refer to document / NRF-TDG