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Chronic obstructive pulmonary disease, pulmonary function and cardiovascular diseaseMcAllister, David Anthony January 2011 (has links)
Cardiovascular disease is common in Chronic Obstructive Pulmonary Disease (COPD), and forced expiratory volume in one second (FEV1) independently predicts cardiovascular morbidity and mortality. Pathological changes in the systemic vasculature have been proposed as potential mechanisms linking COPD to cardiovascular disease, and patients with COPD may be at increased risk of acute myocardial infarction during acute exacerbations. Notwithstanding causation, FEV1 may be a useful prognostic marker in patients undergoing cardiac surgery. This thesis examined these three aspects of cardiovascular co-morbidity in relation to COPD and FEV1. In 2,241 consecutive cardiac surgery patients, FEV1 was associated with length of hospital stay (p<0.001) and mortality (p<0.001) adjusting for age, sex, height, body mass index, socioeconomic status, smoking, cardiovascular risk factors, chronic pulmonary disease, and type/urgency of surgery. In a survey of Scottish Respiratory Consultants there was no consensus regarding the investigation and management of acute coronary syndrome in exacerbation of COPD. In a case-series of 242 patients with exacerbations 2.5% (95% CI 1.0 to 5.6%) had chest pain, raised serum troponin and serial electrocardiogram changes suggestive of acute coronary syndrome. However, over half reported chest pain, while raised troponin was not associated with chest pain or serial ECG changes. Carotid-radial pulse wave velocity (PWV), aortic distensibility, and aortic calcification were measured to assess the relationship of the systemic vasculature to FEV1 and emphysema severity on CT. In adjusted analyses, emphysema was associated with PWV in patients with COPD (p = 0.006) and, in population based samples, with extent of distal aortic calcification (p=0.02) but not with aortic distensibility (p=0.60). This thesis found that FEV1 was associated with mortality and length of hospital stay in patients undergoing cardiac surgery, and that chest pain and raised troponin were common but unrelated in exacerbation of COPD. In the vascular studies distal but not proximal vascular pathology was associated with FEV1, and if COPD is truly related to systemic arterial disease, the distal arterial tree is implicated.
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Supporting the prescription of exercise in spinal cord injured populationsPaulson, Thomas A. W. January 2013 (has links)
Following a spinal cord injury (SCI), participation in regular exercise can enhance physical capacity and performance in activities of daily living. With this in mind, the use of subjective ratings of perceived exertion (RPE) may provide an easy-to-administer alternative to traditional methods of regulating exercise intensity (e.g. heart rate and power output (PO)). A physically active lifestyle is also associated with a reduced risk of cardiovascular disease, in part because exercise exerts anti-inflammatory effects. Examining the plasma response of inflammation-mediating chemical messengers, known as cytokines, to traditional and novel exercise modalities may help maximise the anti-inflammatory potential of regular exercise. Participants with a cervical level SCI successfully self-regulated a 20 min bout of moderate intensity wheelchair propulsion (Chapter three). No differences in physiological or PO responses were observed during the imposed-intensity and self-regulated wheelchair propulsion in the trained population group. In a non-SCI group of novice wheelchair-users, a differentiated RPE specific to the exercising muscle mass (RPEP) was the dominant perceptual signal during submaximal wheelchair propulsion (Chapter four). The novice group successfully self-regulated a 12 min bout of moderate intensity wheelchair propulsion, comprising of a discontinuous 3 x 4 min protocol, using differentiated RPEP. In contrast, a more accurate self-regulation of light intensity wheelchair propulsion was observed when employing traditional overall RPE compared to RPEP. Following strenuous wheelchair propulsion, plasma concentrations of the inflammation-mediating cytokine interleukin-6 (IL-6) were significantly elevated in non-SCI and thoracic level SCI participants (Chapter five). Impaired sympathetic nervous system (SNS) function was associated with a reduced IL-6 response in participants with a cervical level SCI. The plasma IL-6 response to 30 min moderate intensity (60% VO2peak) arm-crank ergometry (ACE) was associated with an elevation in the anti-inflammatory cytokine IL-1 receptor antagonist (IL-1ra) independent of SNS activation (Chapter six). Light intensity ACE resulted in a small, significant plasma IL-6 response but no IL-1ra response. The addition of functional electrical stimulation-evoked lower-limb cycling to concurrent hand cycling, termed hybrid exercise, resulted in a greater plasma IL-6 response compared to moderate intensity hand cycling alone in participants with a thoracic level SCI (Chapter seven).
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Effects of exercise on cardiovascular disease risk markers in South Asian versus White European menArjunan, Saravana P. January 2013 (has links)
Globally, cardiovascular disease (CVD) is a major cause for morbidity and mortality. Exaggerated postprandial lipaemia has been implicated in the development of atherosclerosis, and by lowering postprandial triacylglycerol (TAG) concentrations, atherogenic progression may be delayed. Many studies have revealed that exercise, in particular acute exercise, can attenuate postprandial TAG concentration. Most of this evidence relates to studies conducted in Western participants. South Asians are a population predisposed to CVD, and their adverse lipid profiles and physical inactivity may be among the underlying reasons. Hence, the studies described in this thesis examined the potential of acute bouts of exercise to favourably modify postprandial lipaemia and other CVD risk markers in young, healthy, South Asian men. The first experimental study described in this thesis compared the effect of 60 minutes of brisk walking on postprandial TAG concentration in 15 South Asian and 14 White European men. Trials were conducted over two days with exercise (or rest) taking place on day 1 and postprandial testing on day 2. A key finding from this study was that postprandial TAG, glucose and interleuklin-6 (IL-6) concentrations were elevated in South Asian compared with White European participants after consumption of high fat meals. This study also revealed a non-significant trend for brisk walking to reduce postprandial TAG concentrations in response to high fat meals in both groups. The second experimental study reported here examined the effect of 60 minutes of treadmill running at 70% of max on postprandial lipaemia and other CVD risk makers on the next day in 10 South Asian and 10 White European men. A significant main effect of trial was shown for postprandial TAG, IL-6 and soluble intercellular adhesion molecule-1 (sICAM-1), showing that TAG and IL-6 concentrations were lower on the exercise trial while sICAM-1 concentrations were higher on the exercise trial. In addition, ethnic group differences were observed for postprandial TAG, glucose and insulin concentrations indicating higher values in South Asians than White Europeans. A significant trial by group interaction effect was also observed for TAG, indicating a greater decrease after exercise in the South Asian men than the European men. In the third experimental study in this thesis the effect of 30 minutes of treadmill running on one day was compared with running for 30 minutes on three consecutive days in 11 South Asian men with regards to postprandial lipaemia. Neither a single bout of running nor three consecutive days of running influenced postprandial TAG in response to high fat meals when compared with the response on a control trial. It is not clear why exercise was ineffective in reducing postprandial lipaemia in this study but possibly the energy expenditure of exercise was insufficient to elicit change. The final experimental chapter described in this thesis combined the data from the first three studies. The objective of this chapter was to enhance the sample size in an effort to clarify the effects of acute exercise and to clarify the effects of ethnic group with respect to several fasting and postprandial CVD risk markers. The key findings were: 1) fasting and postprandial TAG and postprandial glucose concentrations were significantly reduced by exercise; 2) There were significant main effects of ethnic group for fasting high density lipoprotein cholesterol (HDL-C), total cholesterol/ HDL-C, IL-6 and systolic blood pressure (SBP), indicating lower values of HDL-C and SBP and higher values of total cholesterol/HDL-C and IL-6 in South Asian participants. Additionally, there were significant main effects of ethnic group for postprandial TAG and IL-6 indicating higher values in South Asian participants. Taken together, these data indicate that South Asians have an adverse CVD risk factor profile in comparison with White Europeans and this may explain, at least in part, their elevated risk of CVD. Importantly, the data produced within this thesis show for the first time that acute bouts of exercise can be effective for lowering postprandial plasma TAG concentrations in South Asians, at least transiently. Thus, exercise has the potential to serve as a non-pharmacological medicine in South Asians.
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Obesity in chronic inflammation using rheumatoid arthritis as a model : definition, significance, and effects of physical activity & lifestyleStavropoulos-Kalinoglou, Antonios January 2009 (has links)
Background: Inflammation is the natural reaction of the body to an antigen. In some conditions, this reaction continues even after the elimination of the antigen, entering a chronic stage; it targets normal cells of the body and causes extensive damage. Rheumatoid arthritis (RA) is such a condition. It associates with significant metabolic alterations that lead to changes in body composition and especially body fat (BF) increases. In the general population, increased body fat (i.e. obesity) associates with a number of health disorders such as systemic low grade inflammation and a significantly increased risk for cardiovascular disease (CVD). Both effects of obesity could have detrimental effects in RA. Increased inflammation could worsen disease activity while obesity could further increase the already high CVD risk in RA. However, obesity in RA has attracted minimal scientific attention. Aims: The present project aimed to: 1) assess whether the existing measures of adiposity are able to identify the changes in body composition of RA patients, 2) if necessary develop RA-specific measures of adiposity, 3) investigate the association of obesity with disease characteristics and CVD profile of the patients, 4) and identify factors that might affect body weight and composition in these patients. Methods: A total of 1167 volunteers were assessed. Of them 43 suffered from osteoarthritis and 82 were healthy controls. These, together with 516 RA patients were used in the first study. Their body mass index (BMI), BF, and disease characteristics were assessed. In the second, third, fourth and fifth studies a separate set of 400 RA patients was assessed. In addition to the above assessments, their cardiovascular profile and more detailed disease characteristics were obtained. For the final study, 126 RA patients were assessed for all the above and also data on their physical activity levels and their diet were collected. Results: Assessments of adiposity for the general population are not valid for RA patients. Thus, we proposed RA-specific measures of adiposity. These are able to better identify RA patients with increased BF. We were also able to find associations between obesity and disease activity. Both underweight and obese RA patients had more active disease compared to normal-weight patients. Obese patients had significantly worse CVD profile compared to normal-weight. The newly devised measures of adiposity were able to identify those at increased risk. However, not all obese individuals were unhealthy and not all normal-weight healthy. Among our patients we were able to identify subtypes of obesity with distinct phenotypic characteristics that warrant special attention. Finally, we were able to identify factors that influence body weight and composition. Cigarette smoking protected against obesity while its cessation associated with increased adiposity. Physical activity was also found to be protective against obesity while diet or inflammation of the disease failed to produce any significant results. Conclusions: Obesity is a significant threat to the health of RA patients. The measures of adiposity developed herein should be used to identify obese RA patients. Physical activity seems like the sole mode for effective weight management in this population. Health and exercise professionals should actively encourage their patients to exercise as much as they can. This study has created more questions than it answered; further research in the association of obesity and inflammation, as well as in ways to treat it, is essential.
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ZHX2 REGULATION OF LIPID METABOLISM AND THE BALANCE BETWEEN CARDIOVASCULAR AND HEPATIC HEALTHCreasy, Kate Townsend 01 January 2015 (has links)
The growing obesity epidemic in America carries with it numerous health risks, including diabetes, increased serum lipid levels, and excess fat accumulation in the liver. If these conditions persist or become exacerbated, they may lead to the development of cardiovascular disease, the current leading cause of death among Americans, or to nonalcoholic fatty liver disease (NAFLD) which can progress to hepatocellular carcinoma (HCC), one of the deadliest forms of cancer. Better understanding of the genes involved in these diseases can lead to improved identification of at-risk individuals and treatment strategies.
Our lab previously identified zinc fingers and homeoboxes 2 (Zhx2) as a regulator of hepatic gene expression. The BALB/cJ mouse strain has a hypomorphic mutation in the Zhx2 gene, causing a 95% reduction in Zhx2 protein expression. The near ablation of Zhx2 in BALB/cJ mice confers protection from cardiovascular disease when fed a high fat diet, yet these mice show increased hepatic lipid accumulation and liver damage. Microarray data indicates Zhx2 may be involved in the regulation of numerous genes involved in lipid metabolism. Recent GWAS studies indicate ZHX2 may contribute to the risk of cardiovascular disease and liver damage in humans as well.
In this dissertation, I characterize the role of Zhx2 expression in the liver and how it affects the risk of both cardiovascular disease and liver damage. I generated liver-specific Zhx2 knockout mice and confirmed Zhx2 regulates several novel targets that could contribute to the fatty liver phenotype seen in BALB/cJ mice. Further studies revealed that hepatic Zhx2 expression is necessary for proper sex-specific expression of several Cyptochrome P450 (CYP) genes and could contribute to gender differences in disease susceptibility. Lastly, I performed studies into the functional role of the Zhx2 target gene Elovl3. A mouse model of HCC revealed that Elovl3 is completely repressed in HCC tumors. Cell viability and cell cycle assays indicate that Elovl3 expression slows cell proliferation and may be important for proper cell cycle checkpoints. Together, these data indicate that Zhx2 and/or its targets could be clinically relevant in the detection, prevention, or treatment of cardiovascular disease, fatty liver, and HCC.
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Development of a bioreactor imaging system for characterizing embryonic stem cell-derived cardiomyocytesAbilez, Oscar John 21 September 2010 (has links)
Cardiovascular disease (CVD) affects more than 70 million Americans and is the number one cause of mortality in the United States. Because the regenerative capacity of adult tissues such as the heart is limited, human embryonic stem cells (hESC) have emerged as a source for potential cardiac therapies. However, despite the use of a variety of biochemical differentiation protocols, current yields of hESC-derived cardiomyocytes (CM) have been low. In the case of hESC-CM, which are inherently electromechanically active, additional forms of inducing a mature cardiac fate have not been fully explored. In order to non-invasively visualize and quantify biochemical, electrical, and mechanical stimulation on hESC-CM differentiation in future studies, a bioreactor imaging system has been developed and is described in this report. / text
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ENDOTHELIAL CELL DYSFUNCTION BY ENVIRONMENTAL CONTAMINANTSOesterling, Elizabeth Grace 01 January 2008 (has links)
Within the last few decades, epidemiological evidence has linked exposure to air pollution, both its particles and its organic components, with cardiovascular disease (CVD) progression. CVD is a life long disease with the disruption of the endothelium being the inaugural event in this inflammatory process. The vascular endothelium is extremely susceptible to environmental insults given its tremendous surface area and that it is in constant contact with blood and components circulating within the blood, including xenobiotics. The endothelium is important as a barrier from blood constituents however, dysfunction of this barrier leads to the influx of lymphocytes and granulocytes that lead to the fatty build‐up characteristic of atherosclerosis.
The studies presented in this dissertation tested the hypothesis that two unique environmental contaminants, alumina nanoparticles and benzo[a]pyrene (B[a]P), lead to increased endothelial cell dysfunction, characterized by increased adhesion molecule expression. Alumina nanoparticles induced vascular cell adhesion molecule‐1 (VCAM‐1), intercellular adhesion molecule‐1 (ICAM‐1), and E‐selectin (ELAM‐1), as well as increased monocyte adhesion to activated endothelium. Polystyrene nanoparticles did not elicit this response. B[a]P induced ICAM‐1 expression, but only after toxification by aryl hydrocarbon receptor (AhR) controlled enzymes. Silencing of either AhR or the membrane microdomains called caveolae attenuated the B[a]P‐induced ICAM‐1 response. It was also shown that the induction of ICAM‐1 occurred by signaling through MEK, p‐38 MAPK, and activator protein‐1 (AP‐1). These data provide a novel mechanism by which air pollutants like B[a]P may cause increased atherosclerosis and describe a new toxicant, alumina nanoparticles, as a possible threat for the development of inflammatory diseases, such as atherosclerosis.
Little is known about dietary interventions capable of alleviating xenobiotic‐induced toxicity. Nutrition is an obtainable and inexpensive means of possible preventative therapy. With this in mind, it was also hypothesized that plant polyphenols, such as flavonoids, can down‐regulate B[a]P‐induced ICAM‐1. Selective flavonoids, containing both a 4’ B‐ring hydroxyl substitution and a 2‐3 C‐ring double bond, protected against B[a]P‐induced ICAM‐1 activation, however this protection did not correlate with the flavonoid’s antioxidant capacity.
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Oral health and cardiovascular diseaseHolmlund, Anders January 2008 (has links)
<p>In the past two decades studies have indicated that oral health might be associated with the prevalence for cardiovascular disease (CVD), although the biological link still remains unknown. Bacteria and inflammatory mediators causing periodontal disease have also been suggested to influence the progression of atherosclerosis.</p><p>The aims of this thesis were to study oral inflammation and associations between different oral health parameters and CVD. </p><p>Inflammatory mediators such as interleukin-1 (IL-1) as well as bone resorption activity (BRA) were significantly higher in gingival crevicular fluid (GCF) from sites with periodontal disease compared to healthy sites. Treatment resulted in a reduction of BRA as well as the levels of IL-1 for most of the diseased pockets. The levels of IL-1 were not correlated to the amount of BRA.</p><p>Number of teeth (NT) was consistently associated to CVD and was the only oral health parameter that related to all-cause mortality and mortality in CVD in a dose-dependent manner. Subjects with <10 teeth had a 7-fold increase risk for mortality in coronary heart disease compared to those with >25 teeth. Furthermore, NT was also significantly associated to the levels of leukocytes and to the metabolic syndrome, which consists of a combination of cardiovascular risk factors.</p><p>Other investigated oral health parameters, such as severity of periodontal disease, number of deepened pockets, and bleeding on probing, were not related to CVD in a consistent way.</p><p> Oral health parameters as well as myocardial infarction (MI) were related to serum antibody levels against Porphyromonas gingivalis (Pg), indicating that Pg might be a link between oral health and MI.</p><p>In conclusion, treatment reduced the increased levels of IL-1 and BRA in GCF from sites with periodontal disease. Oral health was associated to CVD with number of teeth being the only oral health parameter that consistently was associated to CVD. Serum antibody levels against P. gingivalis were related to myocardial infarction (MI) as well as to oral health parameters, suggesting that this bacteria could be a link between oral health and CVD.</p>
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Model-based cardiovascular monitoring in critical care for improved diagnosis of cardiac dysfunctionRevie, James Alexander Michael January 2013 (has links)
Cardiovascular disease is a large problem in the intensive care unit (ICU) due to its high prevalence in modern society. In the ICU, intensive monitoring is required to help diagnose cardiac and circulatory dysfunction. However, complex interactions between the patient, disease, and treatment can hide the underlying disorder. As a result, clinical staff must often rely on their skill, intuition, and experience to choose therapy, increasing variability in care and patient outcome.
To simplify this clinical scenario, model-based methods have been created to track subject-specific disease and treatment dependent changes in patient condition, using only clinically available measurements. The approach has been tested in two pig studies on acute pulmonary embolism and septic shock and in a human study on surgical recovery from mitral valve replacement. The model-based method was able to track known pathophysiological changes in the subjects and identified key determinants of cardiovascular health such as cardiac preload, afterload, and contractility. These metrics, which can be otherwise difficult to determine clinically, can be used to help provide targets for goal-directed therapies to help provide deliver the optimal level of therapy to the patient. Hence, this model-based approach provides a feasible and potentially practical means of improving patient care in the ICU.
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Cardiovascular disease and diabetes or renal insufficiency : the risk of ischemic stroke and risk factor interventionJakobsson, Stina January 2015 (has links)
Background In patients with diabetes mellitus (DM) or chronic kidney disease (CKD), established cardiovascular disease (CVD) is associated with an increased risk of recurrent events and poor outcome. Ischemic stroke after an acute myocardial infarction (AMI) is a devastating event that carries high risks of decreased patient independence and death. Among patients with DM or CKD, the risk of an ischemic stroke within a year following an AMI is not known. Improved risk factor control is required to reduce the likelihood of CVD recurrence. Guidelines recommend target lipid profile and blood pressure values; however, data show that these targets are often not met. Therefore, there remains an urgent need for improved cardiovascular secondary preventive follow- up. Aims The aims of the present studies were to define trends in the incidence and predictors of ischemic stroke after an AMI in patients with DM or CKD. Furthermore to assess whether secondary preventive follow-up with nurse-based telephone follow-up including medication titration after CVD improves risk factor values in patients with DM or CKD and to investigate if this method performs better than usual care to implement a new treatment guideline in diabetic patients. Methods To assess the risk of post-AMI ischemic stroke, patient data were obtained from the Swedish Register of Information and Knowledge about Swedish Heart Intensive Care Admissions (RIKS-HIA). In separate studies, we compared a total of 173 233 AMI patients with and without DM, and 118 434 AMI patients with and without CKD. Within the nurse-based age-independent intervention to limit evolution of disease (NAILED) trial, we investigated a nurse-based cardiovascular secondary preventive follow-up protocol. Patients with acute coronary syndrome, stroke, or transient ischemic attack were randomized to receive either nurse-based telephone follow-up (intervention) or usual care (control). Low-density lipoprotein (LDL-C) levels and blood pressure (BP) were measured at 1 month (baseline) and 12 months post- discharge. Intervention patients with above-target baseline values received medication titration to achieve treatment goals, while the measurements for control patients were forwarded to their general practitioners for assessment. We calculated the changes in LDL-C level and BP between baseline and 12 months post-discharge, and compared these changes between 225 intervention patients and 215 control patients with concurrent DM or CKD. During the course of the NAILED trial, new secondary preventive guidelines for DM patients were released, including a new LDL-C target value. To assess adherence to the new guidelines within the NAILED trial, we compared LDL-C levels in the 101 intervention patients and 100 control patients with DM. Results Ischemic stroke after AMI The rates of ischemic stroke within one-year after admission for an AMI decreased over time, from 7.1% in 1998–2000 to 4.7% in 2007–2008 among DM patients, and from 4.2% to 3.7% during the same time periods for non-diabetic patients. Lower stroke risk was associated with percutaneous coronary intervention (PCI) and initiation of secondary preventive treatments in-hospital. In-hospital ischemic stroke occurred in 2.3% of CKD patients and 1.2% of non-CKD patients, with no change in these incidences over time. The rates of one-year post- discharge ischemic stroke decreased between 2003–2004 and 2009–2010 from 4.1% to 2.5% among CKD patients, and from 2.0% to 1.3% among non-CKD patients. Lower rates of post-discharge stroke were associated with PCI and statins. Cardiovascular secondary preventive follow-up Among DM and CKD patients with above-target baseline values in the NAILED trial, the median LDL-C value at 12 months was 2.2 versus 3.0 mmol/L (p<0.001) and median systolic BP was 140 versus 145 mmHg (p=0.26) for intervention and control patients, respectively. Before the guideline change, 96% of the intervention and 70% of the control patients reached the target LDL-C value (p<0.001). After the guideline change, the corresponding respective proportions were 65% and 36% (p<0.001). Conclusion Ischemic stroke is a fairly common post-AMI complication among patients with DM and CKD. This risk of stroke has decreased during recent years, possibly due to the increased use of evidence-based therapies. Compared with usual care, cardiovascular secondary prevention including nurse-based telephone follow-up improved LDL-C values at 12 months after discharge in patients with DM or CVD, and led to more efficient implementation of new secondary preventive guidelines.
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