Thesis (MScMedSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The purpose of this study was to investigate the association of the selected MYH9 single nucleotide polymorphisms (SNPs) with chronic kidney disease (CKD) and its related co-morbidities in the South African mixed ancestry population residing in Bellville South, Cape Town. In 2008, two landmark studies identified SNPs in the MYH9 gene which explained most of the increased risk for non-diabetic CKD in African Americans. These polymorphisms were later found to be weakly associated with diabetic nephropathy. Three SNPs that exhibited independent evidence for association with CKD were selected (rs5756152, rs4821480 and rs12107). These were genotyped using a Taqman genotyping assay on a BioRad MiniOpticon and confirmed by sequencing in 724 subjects from Bellville South, Cape Town, South Africa. Prevalent CKD was defined based on the estimated glomerular filtration rate calculated using the modification of diet in renal disease (MDRD) formula. Chronic kidney disease was present in 214 subjects (29.6%), 96.3% were stage 3 and only 8 subjects were stage 4. In additive allelic models, adjusted for age and gender, rs5756152 demonstrated an association with kidney function whereby each G allele of rs5756152 increased eGFR by 3.67 ml/min/1.73, reduced serum creatinine by 4.5% and increased fasting plasma glucose by 0.51 mmol/L. When an interaction model was used, the effect of rs5756152 on serum creatinine, eGFR and blood glucose levels was retained, and enhanced, but only in diabetic subjects. In addition, rs4821480 T allele increased eGFR while rs12107 A allele decreased glucose levels in diabetic subjects. In contrast to reports that MYH9 SNPs are strongly associated with non-diabetic end stage renal disease, our study demonstrated that rs5756152 and rs4821480 are associated with early kidney function derangements in type 2 diabetes whilst rs12107 is associated with glucose metabolism. Our findings, along with previous reports, suggest that the MYH9 gene may have a broader genetic risk effect on different types of kidney diseases than previously thought. / AFRIKAANSE OPSOMMING: Hierdie studie het ondersoek ingestel na die verband tussen drie gekose MYH9-enkelnukleotied-polimorfismes (SNP’s) en chroniese niersiekte (hierna ‘niersiekte’), wat verwante ko-morbiditeite insluit, onder ’n Suid-Afrikaanse populasie van gemengde afkoms in Bellville-Suid, Kaapstad. Twee rigpuntstudies het in 2008 op SNP’s in die MYH9-geen afgekom wat verklaar het waarom Afro-Amerikaners ’n hoër risiko vir niediabetiese niersiekte toon. Later is bevind dat hierdie polimorfismes ook ’n swak verband met diabetiese nefropatie het. Drie SNP’s wat elk onafhanklik bewys gelewer het van ’n verband met niersiekte is vervolgens gekies (rs5756152, rs4821480 en rs12107). Die SNP’s is daarná met behulp van die Taqman-toets op ’n BioRad MiniOpticon aan genotipering onderwerp, en is toe deur middel van reeksbepaling by 724 proefpersone van Bellville-Suid, Kaapstad, Suid-Afrika, bevestig. Die voorkoms van niersiekte is bepaal op grond van die geraamde glomerulêre filtrasietempo (eGFR), wat aan die hand van die ‘niersiekte-dieetveranderings’- (MDRD-)formule bereken is. Daar is bevind dat 214 proefpersone (29,6%) aan chroniese niersiekte ly – 96,3% was in fase 3 en slegs agt proefpersone in fase 4. In toegevoegde alleliese modelle wat vir ouderdom en geslag aangepas is, het rs5756152 ’n verband met nierfunksie getoon: Elke G-allel van rs5756152 het eGFR met 3,67 ml/min/1,73 verhoog, serumkreatinien met 4,5% verlaag en vastende plasmaglukose met 0,51 mmol/L verhoog. Toe ’n interaksiemodel gebruik is, is die effek van rs5756152 op serumkreatinien, eGFR en bloedglukosevlakke behou en versterk, hoewel slegs by diabetiese proefpersone. Daarbenewens het die T-allel van rs4821480 eGFR verhoog, terwyl die A-allel van rs12107 ook glukosevlakke by diabetiese proefpersone verlaag het. In teenstelling met bewerings dat MYH9-SNP’s ’n sterk verband met niediabetiese eindstadiumniersiekte toon, het hierdie studie bewys dat rs5756152 en rs4821480 met vroeë nierfunksieversteurings by tipe 2-diabetes verband hou, terwyl rs12107 weer met glukosemetabolisme verbind word. Tesame met vorige studies, doen hierdie navorsingsbevindinge dus aan die hand dat die MYH9-geen dalk ’n groter genetiese risiko-effek op verskillende tipes niersiekte het as wat voorheen vermoed is. / Cape Peninsula University of Technology Research Fund / University of Stellenbosch Merit Bursary

Thesis (MScMedSc (Rehabilitation))--University of Stellenbosch, 2008. / Stroke is the second commonest cause of mortality worldwide and remains a leading cause of adult physical disability. It is estimated that sixty percent of South African stroke survivors require assistance with at least one activity of daily living. This burden is predominantly on the shoulders of mostly untrained caregivers. The process of enabling caregivers to make choices conducive to their own health as well as the health of the stroke survivors is multidimensional. One of the cornerstones of this process is the provision of information. In 1995, the Centre for Rehabilitation Studies of the University of Stellenbosch started to develop a training package for stroke care at home. The training takes the form of an interactive workshop and a booklet with practical information. The aim of this study was to refine and pilot this booklet for implementation with the training. The study found that existing guidelines to evaluate the appropriateness of written material for developing communities (measured by Hugo’s grading model), were inadequate. Consequently, a new checklist, based on twenty existing checklists, was compiled. This list, as well as the Suitability Assessment of Material (SAM), was used to evaluate the booklet and make recommendations for a pre-pilot refinement. Even though this checklist has not been validated, it revealed similar results to the SAM when applied to the booklet. After cosultation with the authors, improvements were effected to the booklet The booklet was tested with four samples of the target audience. The functional literacy of the participants was determined using a standardised literacy test. A fifth sample completed a questionnaire on their preference between the pre- and postrefined booklet. Experts in the field of rehabilitation and graphic design also commented on the booklet. This study confirmed the need of stroke survivors and their caregivers for written health information. The refined booklet was found to be an appropriate tool to address the needs of the target audience. The participants perceived the booklet as useful and comprehensible and the readability level was shown to correspond with the tested literacy level of the samples. However, there is a need for printed material on topics related to stroke not currently covered in the booklet, e.g. spasticity. This study showed that the checklist could be used to tailor written health information that is preferred by the target audience. It confirmed that the testing of printed material with stakeholders could expose additional gaps after applying the checklist. Recommendations for further improvements were made based on the comments of the participants. It is foreseen that the new checklist could be a valuable tool for developing future written health material. Finally, it is recommended that an interdisciplinary team that includes a graphic designer be involvement from the planning stages.

Thesis (MAud (Interdisciplinary Health Sciences. Speech-Language and Hearing Therapy)--Stellenbosch University, 2008. / Over the past decade an increasing number of learners with cochlear implants have been placed in mainstream settings in South Africa (Müller & Wagenfeld, 2003). The aim of the present study was to describe possible factors that influence the initial grade 1 school placement as well as subsequent changes in placement of learners with cochlear implants. Data collection consisted of a retrospective record review of the children implanted at the Tygerberg Hospital-University of Stellenbosch Cochlear Implant Unit and a questionnaire aimed at assessing parental perceptions regarding the basis of grade 1 school placement for their children. The record review incorporated children implanted in 1988, the year of inception of the unit and included the most recently implanted children who have already started grade 1. Results of the 47 participants indicated that multiple factors influenced the selection of grade 1 school placement. Recommendations by professionals and parental preference were the most important determinants in the selection process. The mainstreamed learners were implanted at a much younger age than the learners placed in special school settings and therefore had a longer duration of implant use at the start of grade 1. Subsequent to grade 1 placement, the number of learners in mainstream placement, increased from 55% to 70%. The aspects identified in the study could be utilised when counselling parents during the school placement decision making process. Long term monitoring of the academic achievement of these learners needs to be an aim of future research.

Thesis (MScMedSc (Rehabilitation))--University of Stellenbosch, 2005. / Many South African National Defence Force (SANDF) soldiers have suffered spinal cord injury either in the line of duty or otherwise. This injury affects all spheres of life (physical, emotional, social and psychological). Servicemen are often considered heroes of their country and are often the ones who need to set aside their emotions in order to fulfil their roles as soldiers. However, it is anticipated that a permanent impairment/disability e.g. SCI will have an impact on their quality of life (QOL) and satisfaction with living (SWL). This study aims to explore whether emotional support offered to soldiers with spinal cord injury (SCI) during rehabilitation improve their long-term QOL and SWL. Thirteen soldiers who have been re-employed post injury were asked to complete a selfcompiled, self-administered questionnaire regarding the emotional support offered during rehabilitation and the impact thereof on long-term QOL and SWL. The questionnaire focused on their ratings of the QOL and SWL in different areas of their lives and circumstances and asked what they would advise newly injured individuals regarding SCI and rehabilitation. Data was analysed using a combination of qualitative and quantitative methods. Pearson’s chi-square test and the M-L chi-square tests were used to analyse the data with the Statistica programme. A p-value of < 0.05 were calculated as statistically significant. Emotional support during rehabilitation showed a significant impact on QOL (p=0.0497). Ninety-two percent (n=12) of participants rated their QOL as good or excellent while 77% (n=10) rated their SWL as good. Participants who were older than 26 reported a significantly higher rate of SWL than younger ones (p=0.0292). Furthermore, results showed that the family was the most constant source of support during rehabilitation (54%, n=7). Despite that, 77% (n=10) of participants felt that they received excellent emotional support from the rehabilitation team. The study results are intended to facilitate growth and development in the rehabilitation process and guide professionals in the offering of emotional support.

Thesis (PhD)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Diabetes Mellitus (DM) is synonymous with "B-cell failure". Ligation of the pancreatic duct distally to its confluence into the bile duct has been shown to induce endocrine tissue regeneration from a number of probable sources. The cells responsible for regeneration are supposed to possess either dormant pluripotent stem cell ability and/or the plasticity to undergo metaplasia to form new and surplus endocrine tissue able to replace pathologically and/or experimentally compromised pancreas. The sequence of events (cell lineage) during this process of neogenesis, has been the source of controversy for quite some time as various studies suggest that the cell lineage differs from in vivo and in vitro studies, according to experimental model and species of laboratory animal. The object of this study was to utilise an established experimental laboratory animal model to study islet morphological changes, neogenesis and or both in vivo. Further aims of the study were to determine the extent, sequence and magnitude of pancreatic duct ligation (PDL) induced endocrine neogenesis/morphogenesis in a laboratory rat model using occlusive pancreatic duct ligation. PDL's were performed on six groups of 25 normal adult Sprague-Dawley (SD) rats (300g+) according to the method of Hultquist and Jonsson (1965). Experimental animals were sacrificed at 12 hr intervals from day one post-PDL to day 10 and every 24 hrs thereafter to day 14 as described by Wang, Klëppel, Bouwens (1995). Animals received BrdU (a thymidine marker and cell proliferation indicator) 50mglkg intraperitoneally as described by Wang et al. (1995), one hour prior to removal of the pancreas after which it was fixed in Bouin's solution and histologically processed. Seven consecutive 3-6 urn thick serial sections were sequentially stained with H & E, insulin (I), glucagon (G), somatostatin (ST), pancreatic polypeptide (PP), neuropeptide tyrosine (NPY) and peptide tyrosine tyrosine (PYY). Immunolabeling was done according to the method of Guesdon, Temynck , Avrameas (1979). Double immunolabeling for BrdU and each pancreatic peptide was performed on the sections on days 3,5, 7, 9 and 11 as described by Wang et al (1994). Cellular transformation between one and 3Yz days was characterised by simultaneous total deletion and/or transdifferentiation of the acinar compartment and the appearance of immunoreactive cells for I (11.53 ±1.5%), G (1.85 ±0.8%), pp (1.50 ±0.09%), and ST (1.96 ±0.24%). Changes in the endocrine composition in existing islets, occurred along a pathway that saw PP- and ST-cells invading the islet core, islet mantle glucagon deletion and random appearance of all endocrine cell types within the inter-islet interstitium on day 3Yz. Days 4 to 6Yz saw further endocrine expansion while days 7 to 14 were distinguished by islet reconstitution and consolidation. NPY immunoreactivity appeared on day 4Y2 and persisted intermittently throughout while PVV first appeared on day 4 and disappeared after day 7Yz. The results suggest that PDL firstly induced the development of endocrine tissue distributed haphazardly throughout the space previously occupied by acinar parenchyma. Secondly, the appearance of insulin is preceded by the appearance of PP, glucagon and somatostatin by 24-hours. A still to be determined proportion of the ligation induced endocrine formation appeared to be associated with existing islets, resulting in a number of very large islets, some of which might have secretory access through the glomerularlike capillary network known to occupy the islet core. The remainder appeared to form separate "new" islets, which have a dubious access to the blood stream. In conclusion, if it is true that the pancreas can regenerate some of its endocrine tissue then it has potential clinical implication for the stabilising of diabetes mellitus. Ligated exocrine pancreatic tissue, devoid of its acinar component, has been shown to contain notable quantities of insulin positive cells. This presents intriguing possibilities as an alternative for donor tissue, usually obtained from rat foetuses, during foetal rat pancreas transplantation studies. Pancreas tissue harvested from duct ligated rats could replace the foetal tissue currently used in the treatment of experimental diabetes mellitus in laboratory animals in this laboratory. / AFRIKAANSE OPSOMMING: Diabetes Mellitus is sinoniem met B-sel disfunksie. Endokriene regenerasie kan segmenteel bewerkstellig word deur eksperimentele afbinding van die pankreasbuis distaal tot sy samesmelting met die gemene galbuis. 'n Verskeidenheid van selle word vermoedelik by hierdie proses betrek. Dormante stamselle besit die vermoë en/of plastisiteit om 'n aantal vorms van metaplasie te ondergaan om nuwe en/of oortollige endokriene weefsel te vorm wat patologiese en/of eksperimenteel gekompromiseerde weefsel vervang. Die selontwikkelings volgorde wat tydens hierdie proses plaasvind is al vir 'n geruime tyd die middelpunt van 'n meningsverskil. Sommige studies dui daarop dat die in vivo selontwikkelingsvolgorde verskil van in vitro, volgens eksperimentele model en tipe proefdier gebruik. Die doel van die studie was die gebruik van 'n bestaande eksperimentele laboratorium proefdier model om pankreas eiland morfologiese verandering en/ofneogenese of beide in vivo te evalueer. Die oogmerk van die studie was om die omvang en volgorde van veranderings in die endokriene kompartement (neogenese/morfogenese) te bepaal deur gebruik te maak van 'n pankreas buis afbindings (PBA) model wat totale afsnyding van die buis tot gevolg het. PBA's is uitgevoer op ses groepe van 25 volwasse normale Sprague-Dawley (SD) laboratorium rotte (±300g) soos beskryf deur Hultquist en Jonsson (1965). Proefdiere is elke 12 uur geoffer vanaf dag een post-PBA tot dag tien en elke 24 uur daarna tot dag 14 soos beskryf deur Wang, Bouwens, Kloppel (1995) na die toediening van 50 mg/kg 5-Bromo-2-deoksi-uridien intraperitoneaal ('n selprolifererings aanduider) soos beskryf deur Wang et al. (1995). Die pankreas is werwyder, in Bouin se oplossing gefikseer en histologies geprosesseer. Sewe openvolgende seriesnitte (3-6 urn) is alternatiewelik gekleur met H & E, en immunositochemies, soos beskryf deur Guesdon, Terugnek, Avrameas (1979), vir insulien (I), glukagon (G), somatostatien (ST), pankreatiesepolipeptied (PP), neuropeptied tirosien (NPY) en peptied tirosien-tirosien (PYY). BrdU dubbel-immuunkleuring is ingesluit op dae 3,5, 7, 9 en 11 soos beskryf deur Wang et al. (1994). Sellulêre transformasie tussen dae een en 3~ dae is gekenmerk deur gelyktydige en totale uitwissing en/ofmetaplasie van die asinêre kompartement en die verskyning van selle immunorektiefvir I(11.53 ±1.5%), G (1.85 ±0.8%), PP (1.50 ±0.09%), ST (1.96 ±0.24%). Metaplasie was verantwoordelik vir merkbare veranderings in bestaande endokriene weefsel langs In transformasie weg waar eiland insulien kemselle vervang is deur PP- en ST-selle, glukagon buitelaag uitwissing en die toevallige verskyning van alle endokriene seltipes in the inter-eiland interstitium teen dag 3Y2. Dae 4Y2deur 6~ is gekenmerk deur verdere endokrinetoename terwyl dag 7 deur 14 gekenmerk is deur eiland hersamestelling en konsolidering. NPY immunoreaktiwiteit was vanaf dag 4~, met afwisseling, te bespeur terwyl PVV slegs tussen dae 4 en 7 In verskyning gemaak het. . Die resultate suggereer eerstens, PBA induseer die ontwikkeling van oortollige endokriene weefsel op In lukrake wyse versprei deur die ruimte voorheen deur asinêre parenchiem beset. Tweedens, dat die verskyning van insulien deur dié van PP, glukagon en somatostatien met minstens 24-uur voorafgegaan is. Die verhouding, van nuutgevormde endokriene weefsel wat met bestaande eilande assosieer om In aantal baie groot eilande te vorm, moet nog vasgestel word. Sulke strukture mag moontlik afskeidings toegang hê tot die bloedstroom, deur die glomerulusagtige kapillêre netwerk, in die eilandkern teenwoordig terwyl die oorblywende nuutgevormde endokrine weefsel "nuwe" apparte eilande vorm wat wel of gladnie toegang tot die bloedstroom mag hê nie. As gevolgtrekking, indien dit waar is dat volwasse pankreas eilandweefsel wel regenerasie kan ondergaan, dan het dit kliniese implikasie vir die stabilisering van diabetes mellitus. Weefsel verkry uit PBA bevat geen asinêre weefsel nie maar wel merkbare hoeveelhede endokriene weefsel, veral insulin positief. Dit bied dan interessante alternatiewe as skenker weefsel by fetal rot pankreas oorplantings. PBA en/of die oorplanting van pankreasbuis afgebinde weefsel, na in vitro weefsel kultuur, bied moontlikhede vir die behandeling van diabetes mellitus.

Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Title The Effect of Highly Active Antiretroviral Therapy on Human Papilloma Virus Infection and Cervical Cytological Abnormalities in Women Living With HIV Background Human Papillomavirus (HPV) infection causes cervical cancer. The prevalence of HPV-related dysplastic lesions is significantly higher in patients co-infected with the HI virus and thought to be linked to possible more persistent HPV infection. There is, however, conflicting evidence as to whether treatment of Human Immunodeficiency Virus (HIV) infection with antiretroviral agents may influence cervical HPV infection and the behaviour of Squamous Intraepithelial Lesions (SIL). Aims To examine the effect of the initiation of combination antiretroviral therapy (cART) on: 1) the persistence of cervical Low-grade SIL (LSIL); 2) The progression of cervical LSIL to High-Grade SIL (HSIL); 3) The effectiveness of excision treatment of HSIL 4) HPV genotypes detected, in HIVinfected and uninfected women at the Infectious Diseases Clinic and the Colposcopy Clinic, Tygerberg Teaching Hospital, Cape Town, South Africa. Design and Methods We conducted a retrospective cohort analysis of 1720 women with LSIL of the survival of progression-free-time or time-to-clearance. Time to progression or persistence was compared according to HIV status, antiretroviral treatment and CD4 count. In another retrospective cohort analysis, we investigated the effectiveness of excision treatment in 1848 women who underwent LLETZ or CKC biopsy was used. Logistic regression and survival analysis were used to compare excision treatment failure and recurrence-free time between groups according to HIV status, antiretroviral therapy and CD4 count. To investigate the effect of antiretroviral therapy on the cervical HPV infection, 300 HIV-infected women were prospectively enrolled and followed at 6-monthly interval. Cytological testing and cervical HPV sampling were done at each visit. Biopsy of suspicious lesions and excision treatment were done at colposcopy clinic according to standard a protocol. The Roche Linear array HPV genotyping test was used for HPV detection. Generalized Estimating Equation (GEE) multivariate analysis was applied to investigate the effect of cART on the detection of HPV infection, while adjusting for time-dependent covariates such as CD4 count, sexual activity and excision treatment. The effect on each HPV type was then also compared to the effect on HPV16. Results Overall, we found that there was no difference between the progression of LSIL to HSIL by HIV status. However, among HIV-infected patients, those who started ART before first LSIL had a significantly lower risk for progression (HR 0.66, 95% CI 0.54-0.81). CD4 count did not have an impact on the risk for progression. We also found lower persistence of SIL in the HIV uninfected group (HR 0.69, 95% CI 0.57-0.85) and that cART was independently associated with decreased persistence of LSIL. On the other hand, a higher CD4 count at the time of first LSIL was not associated with lower persistence of the lesion. HIV infected women with HSIL experienced much higher excision treatment failure than uninfected women (53.8% vs. 26.9%, p<0.001). Factors that improved outcome were higher CD4 count and complete excision. cART reduced the risk of detection of any HPV type by 47% (OR 0.53, 95% 0.49-0.58, p<001). When adjusted for covariates, time of exposure to cART and CD4 had a stronger effect. Every month of cART exposure reduced the risk detection of any HPV type with 7%. The effect was also significant on HPV16 alone (OR 0.93, 95% CI 0.90-0.95). All non-oncogenic subtypes were influenced similarly or more strongly than HPV16, as well as oncogenic HPV52. Only one oncogenic subtype HPV subtype, HPV39, was influenced marginally less (ratio of OR 0.95, CI 0.90-0.99, p=0.04). There was an increased risk for any HPV detection at CD4 count<200 (OR 1.63, 95% CI:1.50-1.77), but when adjusted, the time of cART exposure again remained the strongest predictor of risk (OR 0.94, 95% CI:0.93-0.95). Conclusion cART impact the outcome of cervical HPV infection by increasing clearance, decreasing progression of LSIL and recurrence after excision treatment. This effect is time dependent and also associated with CD4 count. Specifically, HPV16 detection risk is also reduced by cART, and all HPV types are influenced at least as much as HPV16, except possibly HPV39. It seems that increased cervical HIVproviral load is associated with HPV detection risk, and both are lowered by cART time. / AFRIKAANSE OPSOMMING: Titel Die Effek van Kombinasie Antiretrovirale Terapie op Menslike Papilloomvirusinfeksie en Servikale Sitologiese Abnormaliteite in Menslike Immuniteitsgebrekvirus-geïnfekteerde Vroue Agtergrond Menslike Papilloomvirusinfeksie (MPV) veroorsaak servikale kanker. Die prevalensie van MPVverwante displastiese letsels is betekenisvol hoër in pasiënte wie ook met Menslike Immuniteitsgebrekvirus (MIV) geïnfekteer is en dit word gereken dat dit te wyte is aan meer persisterende MPV infeksie. Daar is egter teenstrydige bewyse oor of die behandeling van MIV infeksie met antiretrovirale (ART) middels die infeksie met MPV en die gedrag van Plaveisel Intraepiletiële letsels (PIL) kan beïnvloed. Doelwitte Om die effek van die inisiasie van kombinasie ART op: 1) die persistering van Laegraadse PIL (LPIL); 2) die progressie van servikale LPIL na hoëgraadse PIL (HPIL) 3) die sukses van eksisiebehandeling van HPIL; 4) MPV genotypies waarneembaar, in MIV-geïnfekteerde vroue by die Infeksiesiektekliniek en die Kolposkopiekliniek,Tygerberghospitaal, Kaapstad, Suid-Afrika, te ondersoek. Studie-ontwerp en Metodes `n Retrospektiewe kohort-analise op 1720 vroue met LPIL van die oorlewing van progressive-vrye tyd en tyd tot opklaring van PIL is gedoen. Tyd tot progressie of opklaring is vergelyk na aanleiding van die pasiënt se MIV status, behandeling met antiretrovirale terapie en CD4-telling. In nog `n retrospektiewe kohort-analise is die effektiwiteit van eksisiebehandeling in 1848 vroue wie LLETZ or Kouemeskonus eksisie ondergaan het, ondersoek. Logistiese regressie en oorlewingsanalise is toegepas om die voorkoms van onsuksesvolle uitkoms en tyd sonder herhaling van letsels tussen groepe te vergelyk na aanleiding van MIV status, ART en CD4-telling. Om die effek van antiretroviral therapie op servikale MPV infeksie te ondersoek, is 300 MIVgeïnfekteerde vroue opgeneem in `n prospektiewe studie en sesmaandeliks opgevolg. Sitologiese en MPV servikale smere is met elke besoek geneem. Biopsies van verdagte letsels en eksisiebehandeling is by die Kolposkopiekliniek gedoen volgens die standaardpraktyk. Die Roche Linear Array HPV Genotyping toets is gebruik vir MPV deteksie. Algemeen-beraamde vergelyking (GEE) meerveranderlike analise is toegepas om die effek van die anti-MIV terapie op die teenwoordigheid van MPV op die serviks te ondersoek. Die aangepaste effek is ook getoets deur die CD4-telling, die seksuele aktiwiteits- en eksisiebehandelingstatus by elke besoek in ag te neem. Die effek op elke MPV genotipe is laastens dan ook vergelyk met die effek op ‘n spesifieke basislyn genotype; in hierdie geval was MPV16 gekies. Resultate Daar was geen statisties beduidende verskil tussen die progressie van LPIL na HPIL na aanleding van HIV status nie, maar pasiënte wie met ART begin het voordat hulle vir die eerste keer met LPIL gediagnoseer was, het ‘n laer risiko gehad vir progressie (HR 0.66, 95% VI 0.54-0.81). Daar is ook gevind dat dit onafhanklik van die CD4 telling was. Die persistering van PIL was laer in die MIV negatiewe groep (HR 0.69, 95% VI 0.57-0.85), maar ook hier was antiretrovirale behandeling geassosieer met verminderde persistering. Weer eens was daar nie ‘n verband met die CD4 telling nie. MIV-geinfekteerde vroue met HPILwas baie meer geneig tot gefaalde eksisiebehandeling (53.8% teenoor 26.9%, p<0.001). Verbeterde uitkoms was geassosieer met ‘n hoër CD4-telling en ‘n eksisie wat as volledig beskryf was. ART wat reeds voor die eksisiebehandeling begin was, het nie die risiko vir onsuskesvolle uitkoms statisties beduidend verminder nie, maar het egter die risiko vir herhaling van letsels na die eksisie sterk verlaag. ART het die kans dat enige MPV tipe waargeneem sou word, met 47% verlaag (OR 0.53, 95% VI 0.49-0.58, p<001). Wanneer aangepas vir ander faktore, was die tyd wat verloop het sedert ART begin was, sowel as vir die CD4 telling, sterker. Vir elke maand sedert ART begin was, het die kans dat enige MPV tipe waargeneem word, met 7% verminder. `n Soortgelyke effek is op HPV16 alleen gevind (OR 0.93, 95%, VI 0.90-0.95). Die effek was net so sterk of sterker op alle subtipes. Slegs een onkogeniese subtipe, MPV39, was gering minder beïnvloed (ratio van OR 0.95, VI 0.90-0.99, p=0.04). Die kans vir waarneming van enige MPV subtype is hoër wanneer die CD4 telling laer as 200 selle/ɥl is (OR 1.63, 95% VI: 1.50-1.77), maar wanneer aangepas, was die tyd van ART weer eens die sterkste voorspeller van MPV infeksie (OR 0.94, 95% VI:0.93-0.95). Gevolgtrekkings ART verbeter die uitkoms van servikale infeksie met MPV deur progressie en persistering van LPIL en herhaling van PIL na eksisie te verminder. Die effek is tydsafhanklik en word ook deur die CD4 telling beïnvloed. Die kanse dat MPV16 spesifiek waargeneem word, word ook deur ART verminder, en all MPV tipes ondervind dieselfde of groter verlaging van waarnemingsrisiko as MPV16, behalwe miskien MPV39. Ons kon aandui dat verhoogde teenwoordigheid van servikale MIV verband hou met die risiko vir die waarneming van MPV infeksie, en beide word verminer deur die tyd waarmee die pasiënt met ARV terapie behandel is.

Dissertation (PhD)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: Heart failure due to cardiomyopathy or cardiac conduction disease is a major cause of mortality and morbidity in both developed and developing countries. Although defined as separate clinical entities, inherited forms of cardiomyopathies and cardiac conduction disorders have been identified that present with overlapping clinical features and/or have common molecular aetiologies. The objective of the present study was to identify the molecular cause of progressive familial heart block type II (PFHBII), an inherited cardiac conduction disorder that segregates in a South African Caucasian Afrikaner family (Brink and Torrington, 1977). The availability of family data tracing the segregation of PFHBII meant that linkage analysis could be employed to identify the chromosomal location of the disease-causative gene. Human Genome Project (HGP) databases have provided additional resources to facilitate the identification of positional candidate genes. Clinical examinations were performed on individuals of the PFHBII-affected family, and, where available, clinical records of subjects examined in a previous study by Brink and Torrington (1977) were re-assessed. Retrospective data suggested redefining the classification of PFHBII. Subsequently, linkage analysis was used to test described dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM) and cardiac conduction-causative loci on chromosomes 1, 2, 3, 6, 7, 9, 11, 14, 15 and 19 for their involvement in the development of PFHBII. Once a locus was mapped, bioinformatics tools were applied to identify and prioritise positional candidate genes for mutation screening. The retrospective and prospective clinical study redefined PFHBII as a cardiac conduction and DCM-associated disorder and simultaneously allowed more family members to be traced.Fortuitously, candidate loci linkage analysis mapped the PFHBII locus to chromosome 1q32, to a region that overlapped a previously described DCM-associated disorder (CMD1D), by the generation of a maximum pairwise lod score of 3.13 at D1S3753 (theta [θ]=0.0) and a maximum multipoint lod score of 3.7 between D1S3753 and D1S414. However, genetic fine mapping and haplotype analysis placed the PFHBII-causative locus distal to the CMD1D locus, within a 3.9 centimorgan (cM) interval on chromosome 1q32.2-q32.3, telomeric of D1S70 and centromeric of D1S505. Bioinformatics analyses prioritised seven candidate genes for mutation analysis, namely, a gene encoding a potassium channel (KCNH1), an extracellular matrix protein (LAMB3), a protein phosphatase (PPP2R5A), an adapter protein that interacts with a cytoskeletal protein (T3JAM), a putative acyltransferase (KIAA0205) and two genes encoding proteins possibly involved in energy homeostasis (RAMP and VWS59). The PFHBII-causative mutation was not identified, although single sequence variations were identified in four of the seven candidate genes that were screened. Although the molecular aetiology was not established, the present study defined the underlying involvement of DCM in the pathogenesis of PFHBII. The new clinical classification of PFHBII has been published (Fernandez et al., 2004) and should lead to tracing more affected individuals in South Africa or elsewhere. The identification of a novel disease-causative locus may point toward the future identification of a new DCM-associated aetiology, which, in turn, might provide insights towards understanding the associated molecular pathophysiologies of heart failure. / AFRIKAANSE OPSOMMING: Hartversaking as gevolg van kardiomiopatie of kardiale geleidingsiekte is ‘n hoof-oorsaak van mortaliteit and morbiditeit in beide ontwikkelde en ontwikkelende lande. Alhoewel gedefinieer as verskillende kliniese entiteite is oorerflike vorms van kardiomiopatie en kardiale geleidingsstoornisse geïdentifiseer met oorvleuelende kliniese eienskappe en/of molukulêre oorsake. Die doelwit van hierdie studie was om die molukulêre oorsaak van progressiewe familiële hartblok tipe II (PFHBII), ‘n oorerflike kardiale geleidingsstoornis, wat in ‘n Suid-Afrikaanse Kaukasiër familie segregeer (Brink en Torrington, 1977), te identifiseer. Die beskikbaarheid van familie data, beteken dat koppelingsanalise gebruik kan word om die chromosomale posisie van die siekte-veroorsakende geen te identifiseer. Menslike Genoom Projek (MGP) databanke het addisionele hulpbronne beskikbaar gestel om die identifikasie van posisionele kandidaat gene te vergemaklik. Kliniese ondersoeke is uitgevoer op PFHBII-geaffekteerde familielede, en waar beskikbaar is kliniese rekords van persone, wat in ‘n vorige studie deur Brink en Torrington (1977) geassesseer was, herontleed. Retrospektiewe data-analise het die kliniese herdefinisie van PFHBII voorgestel. Daarna is koppelingsanalise gebruik om dilateerde kardiomiopatie (DKM), hipertrofiese kardiomiopatie (HKM) en kardiale geleidingssiekte-veroorsakende loki op chromosoom 1, 2, 3, 6, 7, 9, 11, 14, 15 en 19 te ondersoek vir hul moontlike bydrae tot die ontwikkeling van PFHBII. Toe die lokus gekarteer was, is bioinformatiese ondersoeke gebruik om posisionele kandidaat gene te identifiseer en prioritiseer vir mutasie analise. Die retrospektiewe en prospektiewe kliniese ondersoek het PFHBII herdefinieer as ‘n geleidingsstoornis en DKM-verbonde siekte, en terselfde tyd het dit gelei tot die opsporingvan nog familielede. Toevallig het kandidaat loki-analise die PFHBII lokus op chromosoom 1q32 gekarteer, na ‘n gebied wat met ‘n voorheen-beskyfde DKM-verbonde stoornis (CMD1D) oorvleuel, met die opwekking van ‘n makisimum paargewyse lod-getal van 3.13 by D1S3753 (theta [θ] = 0.0) en ‘n maksimum multipunt lod-getal van 3.7 tussen D1S3753 en D1S414. Genetiese fynkartering en haplotipe-analise het die PFHBII-veroorsakende lokus afwaards van die CMD1D lokus geplaas, in ‘n 3.9 centimorgan (cM) gebied op chromosoom 1q32.2-q32.3, telomeries van D1S70 en sentromeries van D1S505. Bioinformatiese analise het daarnatoe gelei dat sewe kandidaat gene vir mutasie analise geprioritiseerd is, naamlik, gene wat onderskeidelik ‘n kalium kanaal (KCNH1), ‘n ekstrasellulêre matriksproteïen (LAMB3), ‘n proteïen fosfatase (PPP2R5A), ‘n aansluiter proteïen wat met ‘n sitoskilet proteïen bind (T3JAM), ‘n asieltansferase (KIAA0205) en twee gene moontlik betrokke in energie homeostase (RAMP en VWS59) enkodeer. Die PFHBII-veroorsakende geen is nie geïdentifiseer nie, alhoewel enkele volgorde-wisselings geïdentifiseer is in vier van die sewe geanaliseerde kandidaat gene. Alhowel die molekulêre oorsaak van die siekte nie vasgestel is nie, het die huidige studie die onderliggende betrokkenheid van DKM in die pathogenese van PFHBII gedefinieer. Die nuwe kliniese klassifikasie van PFHBII is gepubiliseer (Fernandez et al., 2004) en sal lei tot die identifisering van nog geaffekteerde persone in Suid Afrika of in ander lande. Die identifikasie van ‘n nuwe siekte-verbonde lokus mag lei tot die toekomstige identifikasie van ‘n nuwe DKM-verbonde genetiese oorsaak wat, opsig self, dalk insig kan gee in die molekulêre patofisiologie van hartversaking.

Thesis (PhD)--Stellenbosch University, 2004. / Bibliography / ENGLISH ABSTRACT: Heart failure due to cardiomyopathy or cardiac conduction disease is a major cause of mortality and morbidity in both developed and developing countries. Although defined as separate clinical entities, inherited forms of cardiomyopathies and cardiac conduction disorders have been identified that present with overlapping clinical features and/or have common molecular aetiologies. The objective of the present study was to identify the molecular cause of progressive familial heart block type II (PFHBII), an inherited cardiac conduction disorder that segregates in a South African Caucasian Afrikaner family (Brink and Torrington, 1977). The availability of family data tracing the segregation of PFHBII meant that linkage analysis could be employed to identify the chromosomal location of the disease-causative gene. Human Genome Project (HGP) databases have provided additional resources to facilitate the identification of positional candidate genes. Clinical examinations were performed on individuals of the PFHBII-affected family, and, where available, clinical records of subjects examined in a previous study by Brink and Torrington (1977) were re-assessed. Retrospective data suggested redefining the classification of PFHBII. Subsequently, linkage analysis was used to test described dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM) and cardiac conduction-causative loci on chromosomes 1, 2, 3, 6, 7, 9, 11, 14, 15 and 19 for their involvement in the development of PFHBII. Once a locus was mapped, bioinformatics tools were applied to identify and prioritise positional candidate genes for mutation screening. The retrospective and prospective clinical study redefined PFHBII as a cardiac conduction and DCM-associated disorder and simultaneously allowed more family members to be traced. Fortuitously, candidate loci linkage analysis mapped the PFHBII locus to chromosome 1q32, to a region that overlapped a previously described DCM-associated disorder (CMD1D), by the generation of a maximum pairwise lod score of 3.13 at D1S3753 (theta [θ]=0.0) and a maximum multipoint lod score of 3.7 between D1S3753 and D1S414. However, genetic fine mapping and haplotype analysis placed the PFHBII-causative locus distal to the CMD1D locus, within a 3.9 centimorgan (cM) interval on chromosome 1q32.2-q32.3, telomeric of D1S70 and centromeric of D1S505. Bioinformatics analyses prioritised seven candidate genes for mutation analysis, namely, a gene encoding a potassium channel (KCNH1), an extracellular matrix protein (LAMB3), a protein phosphatase (PPP2R5A), an adapter protein that interacts with a cytoskeletal protein (T3JAM), a putative acyltransferase (KIAA0205) and two genes encoding proteins possibly involved in energy homeostasis (RAMP and VWS59). The PFHBII-causative mutation was not identified, although single sequence variations were identified in four of the seven candidate genes that were screened. Although the molecular aetiology was not established, the present study defined the underlying involvement of DCM in the pathogenesis of PFHBII. The new clinical classification of PFHBII has been published (Fernandez et al., 2004) and should lead to tracing more affected individuals in South Africa or elsewhere. The identification of a novel disease-causative locus may point toward the future identification of a new DCM-associated aetiology, which, in turn, might provide insights towards understanding the associated molecular pathophysiologies of heart failure. / AFRIKAANSE OPSOMMING: Hartversaking as gevolg van kardiomiopatie of kardiale geleidingsiekte is ‘n hoof-oorsaak van mortaliteit and morbiditeit in beide ontwikkelde en ontwikkelende lande. Alhoewel gedefinieer as verskillende kliniese entiteite is oorerflike vorms van kardiomiopatie en kardiale geleidingsstoornisse geïdentifiseer met oorvleuelende kliniese eienskappe en/of molukulêre oorsake. Die doelwit van hierdie studie was om die molukulêre oorsaak van progressiewe familiële hartblok tipe II (PFHBII), ‘n oorerflike kardiale geleidingsstoornis, wat in ‘n Suid-Afrikaanse Kaukasiër familie segregeer (Brink en Torrington, 1977), te identifiseer. Die beskikbaarheid van familie data, beteken dat koppelingsanalise gebruik kan word om die chromosomale posisie van die siekte-veroorsakende geen te identifiseer. Menslike Genoom Projek (MGP) databanke het addisionele hulpbronne beskikbaar gestel om die identifikasie van posisionele kandidaat gene te vergemaklik. Kliniese ondersoeke is uitgevoer op PFHBII-geaffekteerde familielede, en waar beskikbaar is kliniese rekords van persone, wat in ‘n vorige studie deur Brink en Torrington (1977) geassesseer was, herontleed. Retrospektiewe data-analise het die kliniese herdefinisie van PFHBII voorgestel. Daarna is koppelingsanalise gebruik om dilateerde kardiomiopatie (DKM), hipertrofiese kardiomiopatie (HKM) en kardiale geleidingssiekte-veroorsakende loki op chromosoom 1, 2, 3, 6, 7, 9, 11, 14, 15 en 19 te ondersoek vir hul moontlike bydrae tot die ontwikkeling van PFHBII. Toe die lokus gekarteer was, is bioinformatiese ondersoeke gebruik om posisionele kandidaat gene te identifiseer en prioritiseer vir mutasie analise. Die retrospektiewe en prospektiewe kliniese ondersoek het PFHBII herdefinieer as ‘n geleidingsstoornis en DKM-verbonde siekte, en terselfde tyd het dit gelei tot die opsporing van nog familielede. Toevallig het kandidaat loki-analise die PFHBII lokus op chromosoom 1q32 gekarteer, na ‘n gebied wat met ‘n voorheen-beskyfde DKM-verbonde stoornis (CMD1D) oorvleuel, met die opwekking van ‘n makisimum paargewyse lod-getal van 3.13 by D1S3753 (theta [θ] = 0.0) en ‘n maksimum multipunt lod-getal van 3.7 tussen D1S3753 en D1S414. Genetiese fynkartering en haplotipe-analise het die PFHBII-veroorsakende lokus afwaards van die CMD1D lokus geplaas, in ‘n 3.9 centimorgan (cM) gebied op chromosoom 1q32.2-q32.3, telomeries van D1S70 en sentromeries van D1S505. Bioinformatiese analise het daarnatoe gelei dat sewe kandidaat gene vir mutasie analise geprioritiseerd is, naamlik, gene wat onderskeidelik ‘n kalium kanaal (KCNH1), ‘n ekstrasellulêre matriksproteïen (LAMB3), ‘n proteïen fosfatase (PPP2R5A), ‘n aansluiter proteïen wat met ‘n sitoskilet proteïen bind (T3JAM), ‘n asieltansferase (KIAA0205) en twee gene moontlik betrokke in energie homeostase (RAMP en VWS59) enkodeer. Die PFHBII-veroorsakende geen is nie geïdentifiseer nie, alhoewel enkele volgorde-wisselings geïdentifiseer is in vier van die sewe geanaliseerde kandidaat gene. Alhowel die molekulêre oorsaak van die siekte nie vasgestel is nie, het die huidige studie die onderliggende betrokkenheid van DKM in die pathogenese van PFHBII gedefinieer. Die nuwe kliniese klassifikasie van PFHBII is gepubiliseer (Fernandez et al., 2004) en sal lei tot die identifisering van nog geaffekteerde persone in Suid Afrika of in ander lande. Die identifikasie van ‘n nuwe siekte-verbonde lokus mag lei tot die toekomstige identifikasie van ‘n nuwe DKM-verbonde genetiese oorsaak wat, opsig self, dalk insig kan gee in die molekulêre patofisiologie van hartversaking.

Thesis (PhD (Biomedical Sciences. Molecular Biology and Human Genetics))--University of Stellenbosch, 2009.

Thesis (PhD (Biomedical Sciences. Medical Physiology))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Background: There has been a dramatic increase in the use of dietary creatine supplementation among sports men and women, and by clinicians as a therapeutic agent in muscular and neurological diseases. The effects of creatine have been studied extensively in skeletal muscle, but knowledge of its myocardial effects is limited. Objectives: To investigate the effects of dietary creatine supplementation with and without exercise on 1) basal cardiac function, 2) susceptibility to ischaemia/reperfusion injury and 3) myocardial protein expression and phosphorylation and 4) mitochondrial oxidative function. Methods: Male Wistar rats were randomly divided into control or creatine supplemented groups. Half of each group was exercise trained by swimming for a period of 8 weeks, 5 days per week. At the end of the 8 weeks the open field test was performed and blood corticosterone levels were measured by RIA to determine whether the swim training protocol had any effects on stress levels of the rats. Afterwards hearts were excised and either freeze-clamped for biochemical and molecular analysis or perfused on the isolated heart perfusion system to assess function and tolerance to ischaemia and reperfusion. Five series of experiments were performed: (i) Mechanical function was documented before and after 20 minutes global ischaemia using the work heart model, (ii) A H2O filled balloon connected to a pressure transducer was inserted into the left ventricle to measure LVDP and ischaemic contracture in the Langendorff model, (iii) The left coronary artery was ligated for 35 minutes and infarct size determined after 30 minutes of reperfusion by conventional TTC staining methods. (iv) Mitochondrial oxidative capacity was quantified. (v) High pressure liquid chromatography (HPLC) and Western Blot analysis were performed on blood and heart tissue for determination of high energy phosphates and protein expression and phosphorylation. Results: Neither the behavioural studies nor the corticosterone levels showed any evidence of stress in the groups investigated. Hearts from creatine supplemented sedentary (33.5 ± 4.5%), creatine supplemented exercised rats (18.22 ± 6.2%) as well as control exercised rats (26.1 ± 5.9%) had poorer aortic output recoveries than the sedentary control group (55.9 ± 4.35% p < 0.01) and there was also greater ischaemic contracture in the creatine supplemented exercised group compared to the sedentary control group (10.4 ± 4.23 mmHg vs 31.63 ± 4.74 mmHg). There were no differences in either infarct size or in mitochondrial oxygen consumption between the groups. HPLC analysis revealed elevated phosphocreatine content (44.51 ±14.65 vs 8.19 ±4.93 nmol/gram wet weight, p < 0.05) as well as elevated ATP levels (781.1 ±58.82 vs 482.1 ±75.86 nmol/gram wet weight, p<0.05) in blood from creatine supplemented vs control sedentary rats. These high energy phosphate elevations were not evident in heart tissue and creatine tranporter expression was not altered by creatine supplementation. GLUT4 and phosphorylated AMPK and PKB/Akt were all significantly higher in the creatine supplemented exercised hearts compared to the control sedentary hearts. Conclusion: This study suggests that creatine supplementation has no effects on basal cardiac function but reduces myocardial tolerance to ischaemia in hearts from exercise trained animals by increasing the ischaemic contracture and decreasing reperfusion aortic output. Exercise training alone also significantly decreased aortic output recovery. However, the exact mechanisms for these adverse myocardial effects are unknown and need further investigation. / AFRIKAANSE OPSOMMING: Agtergrond: Die gebruik van kreatien as dieetaanvulling het in die afgelope aantal jaar dramaties toegeneem onder sportlui, sowel as mediese praktisyns wat dit as ‘n terapeutiese middel vir die behandeling van spier- en neurologiese siektes aanwend. Die effekte van kreatien op skeletspier is reeds deeglik ondersoek, maar inligting aangaande die miokardiale effekte van die preperaat is beperk. Doelwitte: Om die effekte van kreatien dieetaanvulling met of sonder oefening ten opsigte van die volgende aspekte te ondersoek: 1) basislyn miokardiale funksie, 2) vatbaarheid vir iskemie/herperfusie besering, 3) proteïenuitdrukking en -fosforilering in die miokardium en 4) mitochondriale oksidatiewe funksie. Metodes: Manlike Wistar rotte is ewekansig in kontrole of kreatien aanvullings groepe verdeel. Helfte van elke groep is aan oefening in die vorm van swemsessies, vir ‘n periode van 8 weke, 5 dae per week blootgestel. Gedrags- en biochemiese toetse is aangewend om die moontlike effek van die swemprotokol op die rotte se stres vlakke te bepaal. In hierdie verband is die oop area toets gebruik, asook bloed kortikosteroon vlakke gemeet deur radioaktiewe immuunessais. Harte is daarna uit die rotte gedissekteer en gevriesklamp vir biochemiese en molekulêre analise, of geperfuseer op die geïsoleerde werkhart perfusiesisteem om sodoende funksie en weerstand teen iskemie en herperfusie beskadeging te bepaal. Vyf eksperimentele reekse is uitgevoer: (i) Meganiese funksie is noteer voor en na 20 minute globale isgemie in die werkhart model; (ii) ‘n Water gevulde plastiek ballon, gekoppel aan ‘n druk omsetter, is in die linker ventrikel geplaas om sodoende linker ventrikulêre ontwikkelde druk (LVDP), asook iskemiese kontraktuur te meet; (iii) Linker koronêre arterie afbinding is vir ‘n periode van 35 minute toegepas en die infarktgrootte bepaal na 30 minute herperfusie deur gebruik te maak van standaard kleuringsmetodes; (iv) Mitochondriale oksidatiewe kapasiteit is gemeet; (v) Hoë druk vloeistof chromatografie (HPLC) en Western Blot analises is uitgevoer op bloed en hartweefsel vir die bepaling van hoë energie fosfate (HEFe), sowel as proteïenuitdrukking en -fosforilering. Resultate: Beide gedragsstudies en kortikosteroonvlakke het geen teken van stres in die betrokke groepe getoon nie. Die groep blootgestel aan kreatienaanvulling en oefening se harte het na iskemie funksioneel swakker herstel as harte van die onaktiewe kontrole groep (18.22±6.2% vs 55.9±4.35%; p<0.01), asook ‘n groter ikgemiese kontraktuur in vergelyking met die onaktiewe kontrole groep ontwikkel (31.63±4.74 mmHg vs 10.4±4.23 mmHg). Daar was geen verskille in infarktgrootte of mitochondriale suurstofverbruik tussen die verskillende groepe waargeneem nie. HPLC analise het verhoogde fosfokreatien (44.51±14.65 vs 8.19±4.93 nmol/gram nat gewig, p<0.05) en adenosientrifosfaat (ATP) bloedvlakke (781.1±58.82 vs 482.1±75.86 nmol/gram nat gewig, p<0.05) in kreatien aanvullings vergelyk met die kontrole groepe getoon. Daar was egter geen meetbare veranderings in HEF vlakke in hartweefsel nie. Gepaardgaande hiermee het kreatienaanvulling geen effek gehad op die uitdrukking va die kreatien transporter nie. In vergelyking met onaktiewe kontrole harte was GLUT4, en fosforileerde AMPK en PKB/ Akt beduidend hoër in harte van geoefende rotte met kreatienaangevulling. Gevolgtrekking: Hierdie data dui daarop dat kreatienaanvulling geen effek op basislyn miokardiale funksie het nie. Kreatienaanvulling het egter die miokardium se weerstand teen iskemiese skade verlaag in harte van rotte blootgestel aan oefening: iskemiese kontraktuur is verhoog en aorta-uitset tydens herperfusie is verlaag. Die presiese meganismes hierby betrokke is egter onbekend en vereis dus verdere studie. / Division of Medical Physiology (University of Stellenbosch), The National Research Foundation and the Harry Crossley Fund for financial support.