Introduction: Cardiovascular disease affects a greater proportion of females than it does males, and is responsible for an estimated 52 percent of female deaths per annum, globally. Due to the loss of oestrogen associated with the menopause, post-menopausal females are at elevated risk for hypercholesterolaemia which is a primary risk factor for cardiovascular disease. It has not yet been conclusively established whether resistance training can be used to ameliorate hypercholesterolaemia. Aim: This randomized controlled trial investigated what effect 12 weeks of progressive resistance training would have on plasma lipoproteins in a sample of post-menopausal females. Methods: Caucasian women (n=30 intervention and n=18 control) between the ages of 55 and 65 years who were not taking hormone replacement therapy were recruited. Participants did not smoke, were sedentary, were not taking any form of cholesterol-lowering medication, had at least one cholesterol abnormality at baseline but were otherwise healthy and able to participate in a strength training programme. Following extensive medical pre-screening, information dissemination and voluntary consent, the sample was divided into two groups. The exercise sample undertook 12 weeks of resistance training on five days of the week. The control group received no intervention. Measurements were obtained at baseline and every four weeks thereafter and included measures of strength, biochemistry (oestradiol, testosterone, full blood lipid profile, glycated haemoglobin and sex hormone binding globulin), anthropometry, morphology and self-reports (dietary intake, energy expenditure and the profile of mood states questionnaire). Results: There was no change to low density lipoprotein cholesterol, high density lipoprotein cholesterol, triglyceride content or total cholesterol as a result of the intervention. Back, chest and leg strength increased significantly (p<0.01) (increases of 51 percent, 35 percent and 43 percent respectively from baseline); waist circumference dropped (p<0.01) by 5 percent overall and diastolic blood pressure decreased significantly (-9 percent, p<0.01) in the exercise cohort but no change was noted in the matched control. Dietary intake, energy expenditure and body mass remained unchanged in both samples. Morphology (sum of skinfolds, estimated body fat content and girth measures) did not change and nor did other biochemical measures (HbA1c and sex hormone binding globulin) or hormone levels (oestradiol and testosterone). Despite the lack of overall change, an important finding was noted in individual results where a clear indication of ‘responders’ and ‘non-responders’ emerged. Conclusion: Overall mean results suggest that 12 weeks resistance training undertaken five days of the week was ineffective in reducing hypercholesterolaemia in this sample. Despite there being no identifying characteristics determined in this sample, evidence of responders and non-responders to the intervention indicates that reliance on mean data may not be sufficient when analysing data from exercise interventions. Therefore, while progressive resistance training had a positive effect on strength, waist circumference and diastolic blood pressure, it did not positively influence the plasma lipoproteins in this cohort of post-menopausal women. / Maiden name: Kelly, Janet Erica

Made available in DSpace on 2014-06-11T19:32:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-08Bitstream added on 2014-06-13T20:03:22Z : No. of bitstreams: 1 galhardi_cm_dr_botfm.pdf: 637330 bytes, checksum: b34f8ee4fe9c7e5db5a586c6aa38d77c (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Estudos relacionados às conseqüências metabólicas da ingestão de dietas ricas em sacarose ou frutose ainda são limitados. Assim como os estudos que envolvem a restrição no número de refeições diárias. No presente trabalho foram utilizados 24 ratos machos wistar, de peso inicial médio de 222,69 l 16,49g, divididos aleatoriamente em quatro grupos AD, RT, ADS, RTS com seis ratos cada. O grupo AD foi considerado controle, recebendo dieta basal ad libitum. Os animais do grupo RT receberam a mesma quantidade de dieta ingerida pelo grupo AD, oferecida diariamente no período restrito de duas horas (9:00 às 11:00h). Os animais do grupo ADS receberam ração controle ad libitum e para beber, solução aquosa de sacarose 30% ad libitum. Ratos do grupo RTS foram tratados com a mesma quantidade de ração ingerida pelo grupo ADS, oferecida durante o tempo restrito de 2 horas diárias e solução aquosa de sacarose 30% ad libitum. Após 30 dias de tratamentos os animais foram sacrificados. O soro foi utilizado para determinação do perfil lipídico e marcadores do estresse oxidativo. Restrição no tempo de ingestão alimentar desenvolveu dislipidemia com elevação nos fatores de riscos para aterosclerose, elevação no estresse oxidativo, bem como, diminuição de marcadores de defesa antioxidantes. A elevação na atividade sérica da fosfatase alcalina sugere a existência de alteração hepática. O modelo de dieta rica em carboidratos apresentou característica fenotípica de síndrome metabólica, que foi confirmada pela dislipidemia, acompanhada de hipertrigliceridemia. A restrição no tempo de ingestão alimentar com dieta rica em carboidrato induziu dislipidemia, elevação na ALP sugerindo alteração hepática, bem como elevação nos marcadores de estresse oxidativo e diminuição nas defesas antioxidantes. / Not available.

Orientador: Ethel Lourenzi Barbosa Novelli / Banca: Marília Afonso Rabelo Buzalaf / Banca: Rodrigo Cardoso de Oliveira / Banca: Ana Angélica Henrique Fernandes / Banca: Regina Coeli de Miranda Burneiko / Resumo: Estudos relacionados às conseqüências metabólicas da ingestão de dietas ricas em sacarose ou frutose ainda são limitados. Assim como os estudos que envolvem a restrição no número de refeições diárias. No presente trabalho foram utilizados 24 ratos machos wistar, de peso inicial médio de 222,69 l 16,49g, divididos aleatoriamente em quatro grupos AD, RT, ADS, RTS com seis ratos cada. O grupo AD foi considerado controle, recebendo dieta basal ad libitum. Os animais do grupo RT receberam a mesma quantidade de dieta ingerida pelo grupo AD, oferecida diariamente no período restrito de duas horas (9:00 às 11:00h). Os animais do grupo ADS receberam ração controle ad libitum e para beber, solução aquosa de sacarose 30% ad libitum. Ratos do grupo RTS foram tratados com a mesma quantidade de ração ingerida pelo grupo ADS, oferecida durante o tempo restrito de 2 horas diárias e solução aquosa de sacarose 30% ad libitum. Após 30 dias de tratamentos os animais foram sacrificados. O soro foi utilizado para determinação do perfil lipídico e marcadores do estresse oxidativo. Restrição no tempo de ingestão alimentar desenvolveu dislipidemia com elevação nos fatores de riscos para aterosclerose, elevação no estresse oxidativo, bem como, diminuição de marcadores de defesa antioxidantes. A elevação na atividade sérica da fosfatase alcalina sugere a existência de alteração hepática. O modelo de dieta rica em carboidratos apresentou característica fenotípica de síndrome metabólica, que foi confirmada pela dislipidemia, acompanhada de hipertrigliceridemia. A restrição no tempo de ingestão alimentar com dieta rica em carboidrato induziu dislipidemia, elevação na ALP sugerindo alteração hepática, bem como elevação nos marcadores de estresse oxidativo e diminuição nas defesas antioxidantes. / Abstract: Not available. / Doutor

As the leading cause of death in the United States, coronary heart disease (CHD) is a growing public health problem, despite the fact that many risk factors for the disease are preventable, especially if addressed early in life. The purpose of the current study was to examine the effects of loss-framed versus gain-framed versus information-only health messages on both intention to attend and actual attendance at an appointment to get screened for CHD risk factors (i.e., hypertension, diabetes, and dyslipidemia). It was hypothesized that a population of young adults would be more likely to view screening for CHD risk factors as a low-risk, health-affirming behavior as opposed to a risky, illness-detecting behavior and would thus be more strongly influenced by gain-framed messages than loss-framed messages. Additional goals included the exploration of the extensively researched individual health beliefs of perceived threat (as defined by the health belief model) and health locus of control as they relate to message frames. One hundred forty-three undergraduate students were randomly assigned to either the loss-framed, gain-framed, or information-only control conditions. Framing manipulation checks revealed that participants failed to discern differences in the tone and emphasis of the experimental pamphlets. As a result, no tests of framing effects could be conducted. Sixteen (11.2%) of the 143 participants who participated in Part 1 of the experiment participated in Part 2 (i.e., attended a risk factor screening appointment). Multiple regression analysis revealed risk index, age, and powerful others health locus of control as significant predictors of screening intention. Gender was the only demographic or health related variable that was significantly related to screening outcome, such that women were more likely to get screened than men. Limitations and recommendations are discussed.

Les maladies cardiovasculaires constituent la première cause de décès dans le monde et l’athérosclérose est le premier facteur causal de ces maladies. Parmi les multiples facteurs de risque athéromateux, un facteur est souvent décrit :la modification des lipoprotéines de basse densité (LDLs). Bien que le phénomène d’athérogénèse ne soit pas encore complètement résolu, il est actuellement admis que les LDLs natives passent la paroi vasculaire et s’accumulent au niveau sous-endothélial où elles sont oxydées et endocytées par les macrophages. Une théorie plus récente indique que les LDLs peuvent être également modifiées dans la circulation.<p>Néanmoins, le processus par lequel ces lipoprotéines sont modifiées reste hautement controversé. Depuis quelques années, le modèle de modification des LDLs par la myéloperoxydase est apparu comme un modèle physiopathologique contrairement au modèle longuement utilisé de l’oxydation des LDLs par le cuivre. La myéloperoxydase est une enzyme présente dans les granules primaires des neutrophiles mais qui lors d’inflammations chroniques, comme dans l’athérosclérose, peut se retrouver dans le milieu extracellulaire et former un oxydant puissant qui attaque les protéines, les lipides ou les acides nucléiques. Les LDLs modifiées par la myéloperoxydase ne sont plus reconnues par le récepteur membranaire spécifique pour les LDLs. De plus, très peu d’études ont décrit à ce jour les modifications apportées par la myéloperoxydase aux LDLs.<p>Dans ce contexte, nous avons étudié la spécificité de la myéloperoxydase à modifier les LDLs. Dans ce modèle, la partie protéique de la lipoprotéine est majoritairement touchée. C’est pourquoi nous avons développé et optimisé des méthodes d’analyse par spectrométrie de masse de l’apolipoprotéine B-100, la seule protéine de la LDL. De plus, l’activité de la myéloperoxydase à la surface des LDLs a également été investiguée. <p>Les résultats de ce travail montrent que la myéloperoxydase s’attaque de manière spécifique aux LDLs et que le modèle chimique utilisant de l’acide hypochloreux pour mimer l’action de la myéloperoxydase n’est pas parfait. Enfin, nous avons également observé des changements dans l’activité enzymatique lorsque la myéloperoxydase est adsorbée à la surface des LDLs.<p> / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished

Thesis (M. Med.(Paediatrics and Child Health)) -- University of Limpopo, 2019 / Background: Congenital heart disease (CHD) is a significant contributor to Under 5 Mortality rate(U5MR) in Limpopo. Atrioventricular septal defect (AVSD) is the best ascertained lesion in Limpopo and is strongly associated with Down syndrome. Few children from Limpopo with CHD including AVSD access cardiac diagnostic and surgical services. Objectives: The study aimed to enumerate, describe syndromes associated with AVSD and outcomes of children with AVSD at Pietersburg hospital. Methods: This is a Retrospective study of all children (n=80) diagnosed with AVSD from 1 January 2010 to 31 December 2014 at Pietersburg hospital. Data were drawn from echocardiogram reports and patient records. District Health Information Software (DHIS) data was used to obtain the number of live births per district during the 5 years study period. Results: Eight hundred and sixty six (n=866) patients had a first diagnosis of CHD confirmed on echocardiography and 80 (9.2%) of these had AVSD (an estimated 31.5% of expected cases of AVSD). Eighty four per cent (84%) of AVSD patients were associated with Down syndrome. 42/67 (63%) AVSD patients were referred for surgical assessment and of those 15/42 (36%) had surgery. The median interval between diagnosis and surgery was 13 months. Seventy five percent (n=50/67) of patients defaulted follow up. Conclusion: The study confirmed that most children with AVSD had associated Down syndrome and that the majority of children with AVSD from Limpopo do no access surgery. There is under referral of children with Down syndrome for screening of CHD.

Indiana University-Purdue University Indianapolis (IUPUI) / Factors released from coronary perivascular adipose tissue (PVAT), which surrounds large coronary arteries, have been implicated in the development of coronary disease. However, the precise contribution of coronary PVAT-derived factors to the initiation and progression of coronary vascular dysfunction remains ill defined. Accordingly, this investigation was designed to delineate the mechanisms by which PVAT-derived factors influence obesity-induced coronary smooth muscle dysfunction. Isometric tension studies of coronary arteries from lean and obese swine demonstrated that both lean and obese coronary PVAT attenuate vasodilation via inhibitory effects on smooth muscle K+ channels. Specifically, lean coronary PVAT attenuated KCa and KV7 channel-mediated dilation, whereas obese coronary PVAT impaired KATP channel-mediated dilation. Importantly, these effects were independent of alterations in underlying smooth muscle function in obese arteries. The PVAT-derived factor calpastatin impaired adenosine dilation in lean but not obese arteries, suggesting that alterations in specific factors may contribute to the development of smooth muscle dysfunction. Further studies tested the hypothesis that leptin, which is expressed in coronary PVAT and is upregulated in obesity, acts as an upstream mediator of coronary smooth muscle dysfunction. Long-term administration (3 day culture) of obese concentrations of leptin markedly altered the coronary artery proteome, favoring pathways associated with calcium signaling and cellular proliferation. Isometric tension studies demonstrated that short-term (30 min) exposure to leptin potentiated depolarization-induced contraction of coronary arteries and that this effect was augmented following longer-term leptin administration (3 days). Inhibition of Rho kinase reduced leptin-mediated increases in coronary artery contractions. Acute treatment was associated with increased Rho kinase activity, whereas longer-term exposure was associated with increases in Rho kinase protein abundance. Alterations in Rho kinase signaling were also associated with leptin-mediated increases in coronary vascular smooth muscle proliferation. These findings provide novel mechanistic evidence linking coronary PVAT with vascular dysfunction and further support a role for coronary PVAT in the pathogenesis of coronary disease.

B. Tech. (Department of Biotechnology, Faculty of Applied and Computer Sciences), Vaal University of Technology. / Cardiovascular diseases (CVDs) are the leading cause of death worldwide, and the prevalence thereof is on the rise in developing countries due to the demographic transition and urbanization. The inflammatory process, atherosclerosis, is at the root of the majority of CVDs and is caused by unresolved inflammation. Various cardiovascular risk factors such as hyperglycaemia, dyslipidaemia, hypertension, smoking and aging stimulate the development of atherosclerosis through triggering inflammation. Being in a state of chronic low-grade inflammation therefor places an individual at higher risk of developing CVD, with inflammation playing a cause and effect role. The aim of this study was to investigate the inflammatory status of an elderly black South African population by analysis of inflammatory markers HS-CRP, TNF-α and IL-6, as well as the genetic polymorphism C174G associated with increased serum levels of IL-6 in some populations. The research was conducted in the field of Biomedical Sciences as a quantitative, cross-sectional, analytical observational design. The study was ethically approved and involved collection of 84 blood samples from volunteers in a purposively selected population as part of a larger collaborative study. Serum was used to analyse HS-CRP, TNF-α and IL-6 and DNA was extracted from whole blood for analysis of the C174G polymorphism. The median serum HS-CRP of 6.44mg/L (IQR = 2.82 - 9.86mg/L) fell within the highest risk (>5mg/L) of CVD and 75% of participants were at high (3.01-5mg/L) or very high (>5mg/L) risk. The median TNF-α of 0.00pg/mL was within the normal range and only 2.6% of participants had high serum TNF-α levels. The median serum IL-6 level was 1.92pg/mL and was also within the normal range with only 2.6% of participants who had high serum IL-6 levels. For the C174G polymorphism analysis, 98.6% had the GG, 1.4% the GC genotype and no participants had the CC genotype. The median serum IL-6 level of the homozygous GG group was 6.51mg/L, higher than the 4.13mg/L serum IL-6 of the heterozygous GC group. The difference in IL-6 should be considered with caution as only one participant had the C allele. A highly significant (p=0.001) correlation was found between HS-CRP and IL-6, as well as between IL-6 and TNF-α (p = 0.048). The elderly black Sharpeville community is in an increased inflammatory state which puts them at risk of CVD. The prevalence of the C allele in the C174G polymorphism is low in this population. Further research could be conducted as intervention studies to decrease the inflammatory state of the population and influence health policy changes to improve prevention of CVD.

Thesis (M.Sc. (Physiology)) -- University of Limpopo, 2021 / The purpose of this study was to investigate the effect of cART on renal function and assess the association between renal function and cardiovascular risk factors in a black rural HIV-positive population in Limpopo Province, Mankweng district. We have conducted a cross-sectional study which included both male and female cART-treated patients (n=84), cART-naïve patients (n=27) and HIV-negative controls (n=44). We have measured biomarkers of renal function (plasma cystatin C, clusterin, retinol binding protein 4 [RBP4]) and determined the estimated glomerular filtration rate (eGFR) using the chronic kidney disease-epidemiology collaboration formula (CKD-EPI). We have also measured blood pressure (BP), body mass index (BMI) and fasting blood glucose (FBG). The prevalence of renal dysfunction was similar among the study groups. A significant difference in RBP4 was found among the groups after controlling for covariates (age, gender, alcohol consumption, BMI, systolic blood pressure and FBG) (F (2, 146) = [4.479], p=0.010). The significant difference in RBP4 was specifically observed between the cART-treated and cART-naïve groups (p=0.008). Cystatin C, clusterin and eGFR were not significantly different among the study groups after controlling for the covariates. The cardiovascular risk factors age (β=0.207; p=0.039), CD4+ T-cell count (β=-0.236; p=0.040), and duration of cART (β=0.232; p=0.043) were independently associated with cystatin C. The use of cART independently associated with RBP4 (β=0.282; p=0.004). Age (β=-0.363; p=0.001), CD4+ T-cell count (β=0.222; p=0.034) and duration of cART (β=-0.230; p=0.034) independently associated eGFR. Renal dysfunction is common in this HIV-positive population, with similar rates as the HIV-negative population. Plasma cystatin C as a promising alternative renal biomarker need to be re-evaluated in this HIV-positive population. RBP4 may be a more promising renal function biomarker in the HIV-positive population. Cardiovascular risk factors are associated with renal dysfunction in this rural HIV-positive population and CD4+ T-cell count may be an independent predictor for renal function.

Thesis (M.Sc. (Physiology)) -- University of Limpopo, 2016 / Cardiovascular diseases (CVDs) are major public health problems nowadays in Africa. From prospective studies, it is also known that risk factors for CVDs start early in life and increase morbidity and mortality in sub-Saharan African adults. Mostly the risk factors of CVDs are malnutrition and hypertension. Economic development in South Africa leads to lifestyle changes that contribute to a high prevalence of high blood pressure (BP) and malnutrition. However, little is known about the relationship of anthropometric indicators and BP in children from the developing countries. Therefore the aim of this study was to determine the association between anthropometrics indicators and BP among rural children in Ellisras area of Limpopo province, South Africa. All 1961 children (n=1029 boys, n=932 girls) aged 5-12 years underwent anthropometric and BP measurements using standard procedure. Receiver operating characteristics (ROC) curve was used to assess the ability of anthropometric indicators to discriminate children with high BP. ROC was used to determine the area under curve (AUC), cut-off value, sensitivity and specificity for underweight in children for each age and gender. Linear regression was used to assess the relationship between anthropometric indicators and BP. ROC curve showed that height (AUC = 0.700, 95%Cl 0.581 to 0.818), SH (AUC= 0.690, 95%Cl 0.573 to 0.786) and SH/H (AUC=0.670, 95% 0.533 to 0.807) can significantly (P<0.05) identify Ellisras children with hypertension. AUC for neck circumference (NC) (0.698), mid upper arm circumference (MUAC) (0.677) and body mass index (BMI) (0.636) for boys were statistically significant (P<0.05) for high systolic blood pressure (SBP), while in girls AUC of BMI was not significant (P>0.05) for high diastolic blood pressure (DBP). The regression analysis showed a positive significant (P<0.05) association of SBP with NC (β=0.764, 95%CI 0.475 to 1.052) and MUAC (β=1.286, 95% Cl 0.990 to 1.581) for unadjusted and adjusted age and gender. NC (β=0.628 95% Cl 0.303 to 0.953) and MUAC (β=1.351 95% CI 1.004 to 1.697) showed a significant association with SBP. However, MUAC had a significant association with DBP for both unadjusted and adjusted age and gender. Sitting height (SH) was significantly associated with SBP (β = 0.134, 95% Cl 0.210 to 0.416) and DBP (β = 0.088, 95% Cl 0.086 to 0.259) for unadjusted. After adjusted for age and gender, SH was significantly associated with both SBP (β = 0.161, 95% Cl 0.220 to 0.532) and DBP (β = 0.101, 95% Cl 0.066 to 0.329). There was a positive significant association between BP and anthropometric indicators in this population study, though the association of DBP and NC disappeared after adjustments for age and gender. Furthermore, there is a positive significant association between DBP and SBP with the components of height amongst Ellisras rural children. NC and MUAC are the simplest techniques with good interrater reliability and could be used to screen underweight in children. / Vrije University, Amsterdam, The netherlands University of Limpopo National Research Foundation (NRF)