Includes bibliographical references (21 leaves). Previous studies have found that green tea and its antitoxidant constituents, the catechins, are hypocholesterolaemic in both epidemiological and animal intervetion studies. The main objectives of the present study were to investigate the mechanism by which green tea and its most abundant catechin constituent epigallocatechin gallate increase the low-density lipoprotein (LDL) receptor of HepG2 cells. In addition, it was hoped to determine if a crude catechin extract from green tea could lower plasma cholesterol levels in the hypercholesterolaemic rabbit and ascertain if this effect was due to an increase in the LDL receptor. The study provides evidence that green tea and its catechins exhibit hypocholesterolaemic properties and may therefore provide protection against heart disease.

Includes bibliographical references (21 leaves). / 1 v. (various pagings) : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Previous studies have found that green tea and its antitoxidant constituents, the catechins, are hypocholesterolaemic in both epidemiological and animal intervetion studies. The main objectives of the present study were to investigate the mechanism by which green tea and its most abundant catechin constituent epigallocatechin gallate increase the low-density lipoprotein (LDL) receptor of HepG2 cells. In addition, it was hoped to determine if a crude catechin extract from green tea could lower plasma cholesterol levels in the hypercholesterolaemic rabbit and ascertain if this effect was due to an increase in the LDL receptor. The study provides evidence that green tea and its catechins exhibit hypocholesterolaemic properties and may therefore provide protection against heart disease. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physiology, 2000

The purpose of this dissertation series was to describe sedentary behavior and its associations with cardiovascular disease (CVD) biomarkers and outcomes, and to explore the potential that reducing sedentary behavior may be a secondary prevention target for Acute Coronary Syndrome (ACS) survivors. As such, the following series of research studies evaluate the mechanisms, patterns, and correlates of sedentary behavior in relation to CVD risk and examine whether sedentary behavior might be a risk factor for CVD outcomes among ACS survivors. In Chapter II, a cross-sectional study of young, healthy adults examined a set of biomarkers representing several aspects of endothelial cell health to elucidate the relationship between free-living, habitual sedentary time and endothelial dysfunction. Results showed that there were no differences in measures of endothelial cell injury, endothelial cell reparative capacity, or upper extremity endothelium-dependent vasodilatation in participants with high compared with low volumes of device-measured sedentary behavior in a sample of young, healthy adults. These findings suggest that physiological mechanisms other than endothelial dysfunction may need to be explored as a potential link between habitual prolonged sedentary time and CVD in young adults. Chapter III employed group-based trajectory modeling to identify distinct patterns of sedentary behavior, as measured by accelerometry, in ACS survivors over the 28 consecutive days following hospital discharge, and, secondly, to explore potential correlates of these patterns. Results demonstrated that ACS patients as a group engaged in high volumes of accelerometer-measured sedentary time. Three patterns of sedentary behavior over the first month post-discharge were identified; these involved either gradual or rapid reductions in sedentary behavior. Several measures of disease severity and physical health (e.g., GRACE CVD risk score, physical health-related quality of life), and partner status (i.e., married or partnered or without partner), were associated with the worst patterns of sedentary behavior (i.e., high volume of sedentary time with only a slight decline over time). These findings provide insight on the different patterns of sedentary behavior that emerge as patients resume their daily life over the first month post hospital discharge. Chapter IV, building upon the study presented in Chapter III, examined whether accelerometer-measured sedentary behavior of ACS survivors over the first month post hospital discharge was associated with 1-year health outcomes. The purpose of this study was to understand whether sedentary behavior in the early post hospital discharge period may be an important risk factor in ACS survivors, that might be targeted in secondary prevention strategies. Results demonstrated that the average sedentary behavior over the first month post hospital discharge was not significantly associated with increased risk of 1-year recurrent major adverse cardiovascular events or hospitalizations. These findings do not support sedentary behavior in the early post hospital discharge period as a prognostic risk factor that should be modified in ACS survivors as part of secondary heart disease prevention strategy. However, studies with larger sample sizes, and that evaluate sedentary behavior patterns beyond the first month are needed. Collectively, these studies show that high volumes of sedentary behavior are prevalent in ACS survivors over the first month immediately following hospital discharge. Future work is needed to further study the underlying mechanisms through which sedentary behavior may confer CVD risk and to determine whether sedentary behavior is an important modifiable risk factor in ACS survivors.

No description available.

Positive psychology has led a movement that concentrates on positive characteristics. The current study examined the relationship between positive emotions, negative emotions, flourishing, languishing, and cardiovascular functioning. The study uses guided imagery to help participants recall a negative emotional event and positive emotional event in a counterbalanced order. The reverse order allowed us to examine the differential contributions of stress buffering versus facilitated recovery effects to higher levels of heart rate variability (HRV). The study also examined the relationship between mental health categories and known cardiovascular disease risk. Univariate analysis of variance revealed that positive emotions can serve as a stress buffer and dampen cardiovascular responses to a negative event. Also, analysis revealed a trend for the prediction that positive emotions can facilitate cardiovascular recovery following a negative event. Exploratory analysis did not reveal differences between a facilitated recovery group and a buffering group for cardiovascular measures. Future studies should include tighter control to help compare the differential influences of stress facilitation and stress buffering on cardiovascular functioning. The results from the study indicate that it is still too early to tell whether mental health buffers those individuals from developing CVD, and to answer whether languishing increases the risk of CVD. Longitudinal studies of young individuals without a prior history of any risk of CVD and who are flourishing or languishing might help provide answers to these questions.

BACKGROUND Increasingly, it is recognised that the unique needs of people from culturally and linguistically diverse backgrounds (CaLDB) should be addressed within a framework of cultural competence. To date, there are limited data on the issues facing CaLDB patients in the Cardiac Rehabilitation (CR) setting. Appreciation of an individual???s values, attitudes and beliefs underpins negotiation of behaviour change in the CR setting. Therefore an understanding of patient and professional interactions is of key importance. OBJECTIVES The focus of this study has been to undertake an exploration of CR service delivery to people from culturally and linguistically diverse backgrounds, using Arabic speaking people as an exemplar of a CaLDB group. More broadly, this research project has sought to identify factors, which influence the practice of health professionals towards CaLDB patients, and to develop a model for evaluation of culturally competent health care in the CR setting. The study sought to achieve these aims by addressing the following research questions: 1. In what way do health practitioners in CR adjust their treatment and support to accommodate the perceived needs of CaLDB communities? 2. In what way do factors (such as individual and organisation perspectives) influence the adjustment of clinical practice and service delivery of CR practitioners; and what are practitioners??? and patients??? perception of barriers and facilitators to service delivery? 3. To what level are CaLDB patients satisfied with CR services? This study design is comprised of the following elements: (1) interviews with health practitioners and Arabic speaking background patients as an exemplar of CaLDB patients; (2) review of policy and procedure documents and medical records; and (3) field observation. METHOD This thesis embraces a qualitative approach as the primary method of investigation to align with the exploratory and descriptive nature of the study. The main methods used in the study were: in depth interviews with health professionals and patients; field observations; appraisal of relevant documents and consultation with expert panels. Study samples were selected through a purposive sampling strategy.Data were analysed using the method of content analysis, guided by the research questions. FINDINGS In total, 25 health professionals (20 female and 5 male) and 32 patients (21 male and 11 female) were interviewed. The method of qualitative content analysis was used for data analysis. Data analysis revealed four major themes: 1) The challenging context; 2) Tuning practices; 3) Influencing factors; and 4) Goodness of fit. The study demonstrated a challenging context for CR delivery, both from the perspective of patients and health professionals. Data reveal a process of reflection, negotiation, and navigation of care by CR health professionals in an effort to understand and meet the diverse needs of CALDB patients. CONCLUSION On the basis of the study findings, a process-oriented model of tuning practice to achieve cultural competence in CR delivery is proposed to inform policy, research and clinical practice.

BACKGROUND Increasingly, it is recognised that the unique needs of people from culturally and linguistically diverse backgrounds (CaLDB) should be addressed within a framework of cultural competence. To date, there are limited data on the issues facing CaLDB patients in the Cardiac Rehabilitation (CR) setting. Appreciation of an individual???s values, attitudes and beliefs underpins negotiation of behaviour change in the CR setting. Therefore an understanding of patient and professional interactions is of key importance. OBJECTIVES The focus of this study has been to undertake an exploration of CR service delivery to people from culturally and linguistically diverse backgrounds, using Arabic speaking people as an exemplar of a CaLDB group. More broadly, this research project has sought to identify factors, which influence the practice of health professionals towards CaLDB patients, and to develop a model for evaluation of culturally competent health care in the CR setting. The study sought to achieve these aims by addressing the following research questions: 1. In what way do health practitioners in CR adjust their treatment and support to accommodate the perceived needs of CaLDB communities? 2. In what way do factors (such as individual and organisation perspectives) influence the adjustment of clinical practice and service delivery of CR practitioners; and what are practitioners??? and patients??? perception of barriers and facilitators to service delivery? 3. To what level are CaLDB patients satisfied with CR services? This study design is comprised of the following elements: (1) interviews with health practitioners and Arabic speaking background patients as an exemplar of CaLDB patients; (2) review of policy and procedure documents and medical records; and (3) field observation. METHOD This thesis embraces a qualitative approach as the primary method of investigation to align with the exploratory and descriptive nature of the study. The main methods used in the study were: in depth interviews with health professionals and patients; field observations; appraisal of relevant documents and consultation with expert panels. Study samples were selected through a purposive sampling strategy.Data were analysed using the method of content analysis, guided by the research questions. FINDINGS In total, 25 health professionals (20 female and 5 male) and 32 patients (21 male and 11 female) were interviewed. The method of qualitative content analysis was used for data analysis. Data analysis revealed four major themes: 1) The challenging context; 2) Tuning practices; 3) Influencing factors; and 4) Goodness of fit. The study demonstrated a challenging context for CR delivery, both from the perspective of patients and health professionals. Data reveal a process of reflection, negotiation, and navigation of care by CR health professionals in an effort to understand and meet the diverse needs of CALDB patients. CONCLUSION On the basis of the study findings, a process-oriented model of tuning practice to achieve cultural competence in CR delivery is proposed to inform policy, research and clinical practice.

Thesis (MScMedSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: INTRODUCTION: The mechanism behind obesity-related cardiomyopathies is at present not completely known, however, cardiac insulin resistance has been implicated as one of the main arbitrators of obesity-related cardiovascular disease. A few studies have associated perturbations in the insulin-mediated PI3K/PKB/Akt pathway in mediating this insulin resistance. Moreover, this pathway has been shown to regulate myocardial apoptosis, which in turn has been implicated in a number of cardiovascular diseases. Currently, few studies have compared the early onset and advanced effects of obesity on the heart. AIMS: To compare the early and advanced stages of obesity in terms of myocardial (i) PI3K/PKB/Akt signalling, (ii) apoptotic signalling and (iii) mitochondrial integrity. Furthermore, we aim to assess the cardiac mitochondrial (i) PI3K/PKB/Akt signalling, (ii) apoptotic signalling and (iii) integrity during the advanced stages of obesity. METHODS: Male Wistar rats were randomly assigned to either a control or diet-induced obesity (DIO) group. Controls were fed a standard rat chow diet and the DIO group fed a high caloric diet (standard rat chow supplemented with sucrose and condensed milk). The diets were implemented for either 8 or 20 weeks and thereafter, the body weight, intra-peritoneal fat mass, and fasting blood glucose and insulin levels (including intra-peritoneal glucose tolerance tests (IPGTTs)) were determined. Freeze-clamped hearts from both groups were subjected to cytosolic western blot analysis for PI3K p85 subunit, PKB/Akt, GSK-3α/β, Bad, Bax and Bcl-2. A fraction of each heart was also subjected to WB analysis of the mitochondrial electron transport chain (ETC) complexes (I-V). Thereafter, the above mentioned proteins were also probed for in mitochondria isolated from the 20 weeks group after administering insulin and exposing the hearts to ischemia. Oxidative phosphorylation (OXPHOS) capacity analysis was then conducted on mitochondria isolated from 20 weeks DIO and control groups and thereafter a citrate synthase (CS) activity assay was performed on these mitochondria. RESULTS: After the 8 and 20 weeks diet, the DIOs had significantly increased intra-peritoneal fat mass, fasting plasma glucose and insulin levels, compared to their controls. Cytosolic WB analysis: The tp85, pp85 and pPKB/Akt levels were significantly higher in the DIOs in comparison to the controls after 8 weeks of diet. Furthermore, pBad and Bax expression were significantly elevated in these animals. After 20 weeks of diet, the DIOs had significantly decreased pp85, tPKB/Akt and pPKB/Akt levels. The tBad was significantly elevated, while the Bad phosphorylated over total expression (P/T) ratio was significantly decreased, in these animals. CS activity assay: CS activity was significantly decreased in the DIOs, versus the controls, at 20 weeks. Mitochondrial ETC WB analysis: The subunit expression in complexes I-III and V did not differ significantly after 8 weeks however, the expression was significantly lower in complexes I and II after 20 weeks. Interestingly, the complexes III and V expression was significantly elevated. Mitochondrial OXPHOS analysis: The ADP/O ratio with (1) glutamate or (2) palmitoyl-L- carnitine as substrate, showed a significant decrease in the DIOs at 20 weeks. Mitochondrial WB analysis: The pp85 subunit was significantly elevated in the control and DIO groups, exposed to insulin and ischemia, in comparison to the untreated controls. The Bcl-2 levels were significantly decreased in the insulin and ischemia DIOs, when matched against the untreated DIOs. The tBad expression did not differ significantly between the insulin and untreated controls, while the tBad was significantly augmented in the ischemia controls versus untreated controls. All significant differences were taken as p<0.05. CONCLUSION: The results indicate that the initial stage of diet-induced obesity is associated with cardioprotection as there is augmented PI3K/PKB/Akt pathway signalling and a decrease in apoptotic markers. In contrast, during the advanced stages of obesity a decreased activity in PI3K/PKB/Akt pathway is associated with myocardial apoptosis and decreased mitochondrial function and integrity. / AFRIKAANSE OPSOMMING: INLEIDING: Die meganisme verantwoordelik vir vetsug-verwante kardiomiopatieë is huidiglik nie bekend nie maar kardiale insulienweerstandigheid word geïmpliseer as een van die hoof bemiddelaars van vetsug-verwante hartsiektes. Verskeie studies het versteurings in die insulien-gemediëerde PI3K/PKB/Akt pad geassosieer met die bevordering van hierdie insulienweerstandigheid. Daarbenewens is dit getoon dat hierdie pad betrokke is in die regulering van miokardiale apoptose, wat op sy beurt geïmpliseer is in 'n aantal kardiovaskulêre siektes. Daar is tans min studies beskikbaar wat die vroeë en laat gevolge van obesiteit op die hart vergelyk. DOELWITTE: Om die vroeë en gevorderde stadiums van vetsug te vergelyk in terme van miokardiale (i) PI3K/PKB/Akt seintransduksie, (ii) apoptotiese seintransduksie en (iii) mitokondriale integriteit. Verder, het die studie ten doel om die kardiale mitokondriale (i) PI3K/PKB/Akt en (ii) apoptotiese seintransduksie en (iii) integriteit in die gevorderde stadiums van vetsug te bepaal. METODES: Manlike Wistar rotte is ewekansig toegewys aan óf 'n kontrole of dieet-geïnduseerde vetsug (DIO) groep. Kontroles is met 'n normale rotkos dieet en die DIO groep met 'n hoë kalorie dieet (normale rotkos aangevul met sukrose en kondensmelk) gevoed. Die dieet is vir 8 of 20 weke volgehou en daarna was die liggaamsgewig, intra-peritoneale vet massa, en vastende bloed glukose en insulien vlakke (insluitende intra-peritoneale glukose toleransie toets (IPGTT`s)) bepaal. Gevriesklampte harte van beide groepe is onderwerp aan sitosoliese WB-analise vir die PI3K p85 subeenheid, PKB / Akt, GSK-3α/β, Bad, Bax en Bcl-2. `n Fraksie van hierdie harte is ook onderwerp aan westerse klad analise (WK-analise) van die mitokondriale elektron vervoer ketting (EVK) komplekse (I-V). Daarna is bogenoemde proteïene ondersoek in mitokondrieë geïsoleer uit die 20 weke groep ná die toediening van insulien en die blootstelling van die harte aan iskemie. Die oksigraaf mitokondriale oksidatiewe fosforilering (OXPHOS) kapasiteit analise is dan op mitokondrieë van 20 weke DIO en kontrole groepe uitgevoer en daarna is 'n sitraatsintase (SS) aktiwiteitstoets gedoen. RESULTATE: Na die 8 en 20 weke dieet, het die intra-peritoneale vet massa, vastende plasma glukose en insulien vlakke in die DIOs aansienlik toegeneem, in vergelyking met hul kontroles. Sitosoliese WK-analise: Die tp85, pp85 en pPKB/Akt vlakke was beduidend hoër in die DIOs in vergelyking met die kontroles, na 8 weke van die dieet. Verder is die pBad en Bax vlakke beduidend verhoog in hierdie diere. Na 20 weke van die dieet, het die pp85, tPKB/Akt en pPKB/Akt vlakke beduidend afgeneem in die DIOs, in vergelyking met die kontroles. Die tBad was beduidend verhoog, terwyl die Bad verhouding van gefosforileerde oor die totale proteïen uitdrukking (P/T)-verhouding) beduidend verminder het in hierdie diere. SS aktiwiteitstoets: SS aktiwiteit is beduidend verminder in die DIOs, teenoor die kontroles, op 20 weke. Mitokondriale EVK WK-analise: Die subeenheid uitdrukking in komplekse I-III en V was nie beduidend verskillend na 8 weke nie. Na 20 weke egter, was die uitdrukking aansienlik laer in komplekse I en II. Interessant genoeg, is die uitdrukking aansienlik verhoog in komplekse III en V. Mitokondriale OXPHOS analise: Die ADP/O verhouding met (1) glutamaat of (2) palmitiel-L-karnitien as substraat, het beduidend afgeneem in die DIOs teen 20 weke. Mitokondriale WK-analise: Die pp85 subeenheid was beduidend verhoog in die kontrole en DIO groepe, blootgestel aan insulien en iskemie, in vergelyking met die onbehandelde kontroles. Die Bcl-2 vlakke was beduidend verminder in die insulien en isgemie DIOs, in vergelyking met onbehandelde DIOs. Die tBad uitdrukking het nie beduidend verskil tussen die insulien en onbehandelde kontroles nie, terwyl die tBad beduidend verhoog was in die isgemie kontroles versus onbehandelde kontroles. Alle beduidende verskille is geneem as p<0.05. GEVOLGTREKKING: Die resultate dui daarop dat die eerste fase van dieet-geïnduseerde obesiteit geassosieer is met kardiale beskerming want `n toename in PI3K/PKB/Akt seintransduksie en 'n afname in apoptotiese merkers is waargeneem. In teenstelling, in die gevorderde stadium van vetsug is daar 'n afname in aktiwiteit in die PI3K/PKB/Akt pad wat verband hou met verhoogde miokardiale apoptose en verminderde mitokondriale funksie en integriteit.

The purpose of this research was to obtain information on the content of education within cardiac rehabilitation programs, methods of administering education, what the barriers are to providing education and which professionals administer education.To reach this goal, a questionnaire was modified from a previous study and a pilot study was undertaken to establish reliability of the questionnaire. The questionnaire was then sent to a sample of 100 directors of cardiac rehabilitation programs belonging to The American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR). The questionnaire focused on 13 established areas of education within cardiac rehabilitation programs.Once the questionnaires were completed, the information was transferred to a table format based upon the 13 content areas. The following conclusions were drawn from the research and the data gathered: 11 of the 13 content areas are offered at least 84% of the time, the major barriers for the 13 content areas were lack of time and lack of interest on the patient's behalf, the most frequent methods of education for all 13 content areas were individual education, print materials, and group education, and the primary educator overall for all 13 content areas was the nurse followed by the exercise physiologist and dietitian/nutritionist. / Department of Physiology and Health Science