Background: Globally, the number of adolescents living with perinatally-acquired HIV continues to rise including in Malawi. To date, this group has received relatively less attention in the field of HIV care; yet they are increasingly surviving into adulthood. There is a growing need for the development of appropriate care and support services for this group; however their sexual and reproductive health (SRH) needs remain poorly addressed. Research Aim: This study aimed to explore perinatally-infected young women’s experiences of growing up with HIV in order to understand their SRH outcomes within their wider socio-cultural and structural context. Methods: A qualitative case study design was adopted whereby each ‘case’ comprised a female adolescent (15-19 years), a nominated caregiver and a service provider. Data was collected for 14 cases through in-depth interviews. The interviews with adolescents were based on an innovative visual method known as ‘my story book’. Results: The study found that young women endured multiple losses that negatively impacted upon their sense of self and belonging. Emotional, material and social support were essential in helping them to build a sense of identity, but their access to such resources was highly variable. Young women’s strategies to seek love, acceptance or support often led them to take sexual risks and left them with little control over their reproductive health. Both the service providers and caregivers often ‘turned a blind eye’ to young women’s sexual activities, leading to poor SRH outcomes. Lack of open discussion on SRH issues was related to cultural and religious norms hindering young women’s access to information and contraception. Conclusion: Addressing the complex needs of the young women poses a key challenge for Malawi’s HIV services. One way forward is to explore ways in which services could develop integrated models of care, offering a ‘one-stop shop’ to this vulnerable group.

No description available.

No description available.

Hepatitis C virus (HCV) causes acute and chronic liver diseases in humans. Its two envelope proteins, E1 and E2, are heavily glycosylated. They interact with host cell receptors and provide a target for host immune recognition. The host virus interactions determine the pathogenesis and outcome of HCV infection. L-ficolin is a soluble pattern recognition molecule of importance in innate immune defence against microorganisms. It activates the lectin complement pathway upon binding to carbohydrate recognition patterns on microorganisms. It was hypothesised that L-ficolin could interact with HCV glycoproteins. Both recombinant and serum derived L-ficolin were investigated for binding to the envelope glycoprotein E1E2 of HCV. Specific, dose-dependent binding of L-ficolin to HCV glycoprotein E1E2 was observed. The interaction between L-ficolin and HCV particles in infected sera was also demonstrated. Binding of L-ficolin to HCV pseudoparticles expressing E1E2 glycoproteins resulted in neutralisation of virus infectivity. The serum L-ficolin level was significantly higher in patients with mild HCV liver fibrosis compared to patients with severe HCV liver fibrosis. These results suggest a potential protective effect of L-ficolin, as an innate immune defence, against HCV infection. To study the role of anti-HCV E1 and E2 (anti-E1E2) in HCV disease, the levels of anti-E1E2 antibodies were evaluated in 230 sera of patients with chronic hepatitis C by enzyme-linked immunosorbent assay. The antigens used were recombinant HCV glycoproteins derived from genotype 1 (H77c) and genotype 3 (UKN3A1.28). Seroreactivity was greater when sera were tested against antigen derived from their homologous genotype than against heterologous antigen. The seroreactivity was inversely proportional to the viral load and to the degree of liver fibrosis. These results demonstrate that seroreactivity against E1E2 depends upon the genotypic origin of the E1E2 antigens and the infecting genotype, and suggest a possible protective effect of anti-E1E2 against disease progression.

Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: This thesis consists of four chapters that present research findings on Colletotrichum diseases associated with Proteaceae worldwide. The first chapter is a review of literature regarding the taxonomy and histology of Colletotrichum species associated with Proteaceae. The literature is not restricted to Proteaceae hosts, as information regarding Colletotrichum on Proteaceae is very limited. In chapter two, Colletotrichum spp. associated with proteaceous hosts growing in various parts of the world were identified based on morphology, sequence data of the internal transcribed spacer region (ITS-I, ITS-2), the 5.8S gene, and partial sequences of the B-tubulin gene. Four species of Colletotrichum were associated with Proteaceae. Colletotrichum gloeosporioides was isolated from Protea cynaroides cultivated in South Africa and Zimbabwe and from a Leucospermum sp. in Portugal, but is known to occur worldwide on numerous hosts. A recently described species, C. boninense, was associated with Zimbabwean and Australian Proteaceae, but also occurred on a Eucalyptus sp. in South Africa. This represents a major geographical and host extension for the species, and a description of the African strains is provided. Colletotrichum crassipes was represented by a single isolate obtained from a Dryandra plant in Madeira. Colletotrichum acutatum was isolated from Protea and Leucadendron in South Africa as well as from other proteaceous hosts occurring elsewhere. Colletotrichum acutatum f. sp. hakea was isolated from Hakea in South Africa. In chapter three, pathogenicity of these Colletotrichum species to certain proteas was established, relative aggressiveness of the different species tested and host response to them were compared as well as the effect that wounding had on host response. From the results obtained it is concluded that C. acutatum and C. gloeosporioides are the primary pathogens associated with Colletotrichum leaf necrosis, and C. acutatum is the main cause of anthracnose and stem necrosis of Proteaceae in South Africa. A histological study was performed in chapter four in response to the findings from the previous chapter. The behaviour of two C. acutatum isolates (one originating from Protea and the other from Hakea, C. acuataum f.sp. hakea) was studied on inoculated Protea leaf surfaces using light and scanning electron microscopy. Colletotrichum acutatum from Protea formed melanised appressoria on the leaf surface, whereas C. acutatum from Hakea formed very low numbers of both melanised and unmelanised appressoria. Most of the appressoria formed by C. acutatum from Protea were formed on the cell junctions and on the periclinal walls of the epidermal cells. From this study it is clear that C. acutatum f. sp. hakea is not a pathogen of Protea. Consequently the current use of this isolate as a biological control agent of Hakea in South Africa poses no threat to indigenous Protea species. Colletotrichum acutatum from Protea (although closely related to C. acutatum f. sp. hakea), is a pathogen of Protea, which was confirmed by histological observations. In conclusion, the present study has shown that several species of Colletotrichum are associated with diseased Proteaceae. These species differed in their pathogenicity and aggressiveness when inoculated onto certain protea cultivars. These differences could be partially explained by examining the behaviour of C. acutatum on the leaf surface. It is clear, however, that the distribution of the different species, their aggressrveness on different Proteaceae and their modes of infection needs to be investigated further. This work provides a basis for future research on the long-term effective management of these pathogens in fynbos production. / AFRIKAANSE OPSOMMING: Hierdie tesis bestaan uit vier hoofstukke wat handeloor navorsing van Colletotrichum siektes van Proteaceae wêreldwyd. Die eerste hoofstuk is 'n oorsig van literatuur rakende die taksonomie en histologie van die Colletotrichum spesies wat met Proteaceae geassosieer word. Die literatuur oorsig is nie beperk tot die Proteaceae nie aangesien baie min inligting rakende Colletotrichum op Proteaceae bestaan. In die tweede hoofstuk word die Colletotrichum spesies wat met proteas in verskeie dele van die wêreld geassosieer word, op grond van morfologie, DNS volgorde data van die interne getranskribeerde spasieerder area ("ITS-I, ITS-2"), die 5.8S geen, en gedeeltelike DNS volgordes van die B-tubulin geen geïdentifiseer. Vier Colletotrichum spesies is met die Proteaceae geassosieer. Colletotrichum gloeosporioides is geïsoleer vanaf Protea cynaroides wat in Suid-Afrika en Zimbabwe gekweek is en vanaf 'n Leucospermum sp. in Portugal, maar is bekend op verskeie gashere wêreldwyd. 'n Spesie wat onlangs beskryf is, C. boninense, is met Zimbabwiese en Australiaanse Proteaceae geassosieer, maar kom ook op 'n Eucalyptus sp. in Suid-Afrika voor. Dit is 'n groot uitbreiding van die geografiese voorkoms en gasheerreeks van hierdie spesie en 'n beskrywing van die Afrikaanse rasse word gegee. Colletotrichum crassipes is verteenwoordig deur 'n enkele isolaat wat vanaf 'n Dryandra plant in Madeira verkry is. Colletotrichum acutatum is vanaf Protea en Leucadendron in Suid-Afrika asook vanaf ander proteas wat elders voorkom, geïsoleer. Colletotrichum acutatum f. sp. hakea is vanaf Hakea in Suid-Afrika geïsoleer. In hoofstuk drie is die patogenisiteit van hierdie Colletotrichum spesies teenoor sekere proteas getoets, die relatiewe aggressiwiteit van die verskillende spesies is vergelyk, asook die gasheer se reaksie teenoor die spesies en die effek wat verwonding op die gasheer gehad het. Daar kan afgelei word vanaf die resultate dat C. acutatum en C. gloeosporioides die primêre patogene is wat met Colletotrichum blaarnekrose geassosieer word, en dat C. acutatum die hoof oorsaak is van antraknose en lootnekrose van Proteaceae in Suid-Afrika. 'n Histologiese studie is in hoofstuk vier uitgevoer in reaksie op die bevindings van die vorige hoofstuk. Die gedrag van twee C. acutatum isolate (een vanaf Protea en die ander vanaf Hakea, C. acutatum f.sp. hakea) op die oppervlaktes van geïnokuleerde Protea blare is bestudeer deur gebruik te maak van lig- en skandeer-elektronmikroskopie. Colletotrichum acutatum vanaf Protea vorm gemelaniseerde appressoria op die blaaroppervlak, terwyl C. acutatum vanaf Hakea klein hoeveelhede van beide gemelaniseerde en ongemelaniseerde appressoria vorm. Meeste van die appressoria wat deur C. acutatum vanaf Protea gevorm word, vorm op die aanhegtingspunte tussen selle en op die periklinale wande van die epidermale selle. Vanuit hierdie studie is dit duidelik dat C. acutatum f. sp. hakea nie 'n patogeen van Protea is nie. Gevolglik hou die huidige gebruik van hierdie isolaat as biologiese beheer agent van Hakea in Suid-Afrika geen gevaar in vir inheemse Protea spesies nie. Colletotrichum acutatum vanaf Protea (alhoewel dit naverwant is aan C. acutatum f. sp. hakea) is 'n patogeen van Protea en hierdie stelling is ook bevestig deur histologiese waarnemmgs. Ter samevatting het hierdie studie getoon dat verskeie Colletotrichum spesies geassosieer word met siektes van Proteaceae. Hierdie spesies het van mekaar verskil rakende patogenisiteit en aggressiwiteit nadat hulle op sekere protea kultivars geïnokuleer is. Hierdie verskille kon gedeeltelik verklaar word deur die gedrag van C. acutatum op die blaaroppervlaktes van verskillende protea kultivars. Dit is duidelik dat die verspreiding van die verskillende spesies, hulle aggressiwiteit op verskillende Proteaceae en hul infeksie metodes verder ondersoek moet word. Hierdie studie verskaf 'n basis vir toekomstige navorsing rakende lang-termyn effektiewe bestuur van hierdie patogene in fynbos aanplantings.

published_or_final_version / Botany / Master / Master of Science

published_or_final_version / Botany / Master / Master of Science

published_or_final_version / Dentistry / Master / Master of Dental Surgery

published_or_final_version / Medicine / Master / Master of Research in Medicine

published_or_final_version / Medicine / Master / Master of Public Health