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Dissertations / Theses on the topic 'Cardiovascular conditions'
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FEVOLA, ELISA. "Boundary conditions estimation techniques for cardiovascular modeling." Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2972100.
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Arif, Sayqa. "Investigating the role of nitric oxide clones in cardiovascular conditions." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5299/.
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Previously thought to be inert, nitrite is now deemed to be an important endogenous source of nitric oxide (NO), particularly during hypoxia and ischaemia. Largely animal and some limited human studies propose a role for nitrite in ‘hypoxic vasodilatation’ and ischaemia-reperfusion injury. One study explores the effect of systemic nitrite infusion on cardiac and peripheral haemodynamic parameters in healthy subjects, during normoxia and hypoxia. Despite a lack of observed effects in healthy subjects, a study performed in patients with heart failure during normoxia demonstrated favourable haemodynamic effects on cardiac output, albeit at high doses of nitrite. In patients undergoing coronary artery bypass surgery, low dose nitrite infusion afforded protection against ischaemia-reperfusion injury. Several mechanisms of nitrite reduction to NO have been described and remain to be fully elucidated. The role of one of these putative mechanisms, namely mitochondrial aldehyde dehydrogenase (ALDH2) was explored during normoxia and hypoxia. Ex vivo human vascular ring studies confirmed ALDH2 as an important nitrite reductase, in contrast to in vivo observations in the forearm vasculature, suggesting that numerous mechanisms are involved in vivo which are harder to isolate. Furthermore, this hypoxia vasodilatory role was not replicated in with GTN in the human forearm vasculature.
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Adeyemi, Oladipupo. "Exploring novel applications for ursodeoxycholic acid in the treatment of cardiovascular conditions." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/39570.
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As a bile acid, ursodeoxycholic acid (UDCA) is found endogenously formed in humans and other mammals where it is primarily involved in lipid metabolism. It is approved under a number of different brand names for the treatment of gallstones and Primary Billiary Cholangitis (PBC). Previous studies in cardiac cell models of Intrahepatic Cholestasis of Pregnancy (ICP) have demonstrated that UDCA can also be protective against the conduction slowing effects of the bile acid, taurocholic acid (TC). Therefore, this thesis aimed to identify novel applications for UDCA in the treatment of fetal arrhythmiasin ICP. It describes the development of a novel isolated-perfused neonatal rat heart model as a model of the fetal heart (FH) and an adult female rat heart model as a model of the maternal heart (MH) for evaluating the mechanism of bile acid induced arrhythmias. Using optical mapping and electrocardiogram (ECG) recording techniques, it separately evaluated TC effects in the atria and ventricles of the FH and compared them to effects in the MH model. It also evaluated the effects of UDCA in ischemia in a pilot study. It was observed that TC treatment induced significant conduction slowing in both the atria (ECG PR interval prolongation) and ventricles of the FH, but as occurs in ICP, these effects were absent or less pronounced in the MH model. Interestingly, co-administration of UDCA with TC was protective as it inhibited the observed conduction slowing effects. Using selective cardiac calcium channel blockers, it demonstrated that the conduction slowing effects of TC were mediated by blockade of the T-type calcium channel subtype. This was confirmed using the patch clamp technique that demonstrated that TC reduces the calcium current amplitude in neonatal rat and adult human fetal cardiomyocytes and this effect was inhibited with UDCA treatment. No beneficial effects were identified for UDCA in the treatment of acute global ischemia.
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Shi, Yubing. "Lumped-parameter modelling of cardiovascular system dynamics under different healthy and diseased conditions." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/4198/.
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Cardiovascular disease is the most common cause of death in the modern society, and research into the diagnosis and treatment of cardiovascular diseases is an urgent task. Lumped-parameter mathematical modelling as an efficient and effective research technique has been extensively applied in the cardiovascular dynamics research, and has achieved enormous success in assisting the cardiovascular physiology study. This thesis reports a coherent work of lumped-parameter cardiovascular modelling based on some selected works that the author has conducted and published in the past several years. After a critical and comprehensive review of the concurrent lumped-parameter modelling technique, an improved lumped-parameter model that effectively describes the important cardiovascular features of heart valve dynamics and atrial-ventricular septum motion is presented. The model is then adapted to study several application cases of typical heart failure condition with ventricular assist device support, and extension of the lumped-parameter modelling for the optimisation of a pulsatile bioreactor in cardiovascular tissue engineering study. Some on-going works and future directions are also introduced. The reported modelling studies are useful for the cardiovascular physiology research and design optimisation of cardiovascular prosthetic organs.
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D'Ascenzi, Flavio. "Atrial function and loading conditions in athletes." Doctoral thesis, Umeå universitet, Institutionen för folkhälsa och klinisk medicin, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-134873.
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Intensive training is associated with hemodynamic changes that typically induce an enlargement of cardiac chamber. Despite LA dilatation in athletes has been interpreted as a benign adaptation, little evidence is available. The aim of this thesis is to demonstrate that LA size changes in response to alterations in loading conditions and to analyse atrial myocardial function in athletes through the application of novel echocardiographic techniques. We found that top-level athletes exhibit a dynamic morphological and functional LA remodelling, induced by training, with an increase in reservoir and conduit volumes, but stable active volume. Training causes an increase in biatrial volumes which is accompanied by normal filling pressures and stiffness. These changes in atrial morphology are not associated with respective electrical changes. Extending the evidence from adult athletes to children, we found that training-induced atrial remodelling can occur in the early phases of the sports career and is associated with a preserved biatrial function. Finally, in a meta-analysis study of the available evidence we demonstrated that atrial function and size are not affected by aging. In conclusions, athlete’s heart is characterized by a physiological biatrial enlargement. This adaptation occurs in close association with LV cavity enlargement, is dynamic and reversible. This increase in biatrial size is not intrinsically an expression of atrial dysfunction. Indeed, in athletes the atria are characterized by a preserved reservoir function, normal myocardial stiffness, and dynamic changes in response to different loading conditions.
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Brauer, Paula Mae. "Familial aggregation of diabetes, hypertension and cardiovascular conditions in a case-control study of colorectal neoplasia." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0023/NQ49836.pdf.
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Rodier, Marion. "Impact du t-PA sur les taux cérébraux de BDNF en conditions physiologiques et sur les taux circulants en conditions ischémiques : études chez l' Homme et chez l'animal." Thesis, Dijon, 2014. http://www.theses.fr/2014DIJOS054/document.
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L’objectif de ce travail a été de tester l’hypothèse selon laquelle l’effet bénéfique de l’administration de la forme recombinante de l’activateur tissulaire du plasminogène (rt-PA) chez le patient victime d’un accident vasculaire cérébral (AVC) ischémique ne résulte pas uniquement de son action fibrinolytique mais aussi de sa capacité à augmenter le brain-derived neurotrophic factor (BDNF) dans le cerveau. Dans ce but, nous avons conduit une première étude visant à évaluer chez l’animal sain, l’effet du rt-PA sur les taux cérébraux de BDNF. Dans une seconde approche, nous avons étudié l’effet du rt-PA sur les taux sériques de BDNF chez le patient victime d’un AVC ischémique et chez l’animal soumis à une ischémie cérébrale focale. Le sang a été prélevé chez l’Homme à l’admission (J0), J1, J7 et J90 après l’AVC, et chez le Rat avant et après (1h, 4h et 24h) l’ischémie. Le BDNF a été mesuré dans le cerveau par technique de Western blot et dans le sang par technique ELISA. Dans les deux études le rt-PA (Actilyse®) a été administré sous forme d’un bolus suivi d’une perfusion d’une heure. La première étude montre que 1) le rt-PA augmente les taux de BDNF dans l’hippocampe, 2) le traitement par MK801 (un antagoniste des récepteurs NMDA) mais pas par l’acide tranexamique (un inhibiteur de la plasmine) annule l’effet du rt-PA sur les taux de BDNF. La deuxième étude met en évidence que 1) la récupération neurologique est meilleure chez les patients recevant le rt-PA, 2) le traitement par rt-PA augmente les taux sériques de BDNF à J1 et J7 chez l’Homme, mais ne modifie pas les taux sanguins de BDNF chez l’animal, 3) les taux de BDNF ne sont pas corrélés à la récupération neurologique mais sont inversement corrélés au score cardiovasculaire du patient. En conclusion, nos résultats suggèrent que le rt-PA peut exercer un effet protecteur extra-fibrinolytique en augmentant les taux de BDNFm par une potentialisation de l’activité glutamatergique. Même si le rt-PA induit une meilleure récupération neurologique et augmente les taux circulants de BDNF chez les patients victimes d’un AVC, l’absence de corrélation entre ces deux paramètres n’est pas en faveur de l’utilisation du BDNF circulant comme un marqueur prédictif de récupération neurologique, mais pourrait être un reflet de la capacité de l’endothélium à sécréter le BDNFOur objective was to test the hypothesis that the beneficial effect of the administration of the recombinant form of tissue plasminogen activator (rt-PA) in ischemic stroke patient not only results from its fibrinolytic activity but also from its ability to increase brain-derived neurotrophic factor (BDNF) in the brain. To this end, we conducted an initial study to evaluate the effect of rt-PA on brain BDNF levels in healthy animals. In a second study, we investigated the effect of rt-PA on serum BDNF levels in ischemic stroke patients and in animals subjected to permanent focal cerebral ischemia. Blood samples were obtained from patient on admission (D0), D1, D7 and D90 after stroke and in rats before and after (1h, 4h and 24h) ischemia. BDNF was measured in the brain by Western blot and in the blood by ELISA. In both studies, the rt-PA (Actilyse®) was administered as a bolus followed by an infusion of one hour. The first study evidences that 1) rt-PA increases the BDNF levels in the hippocampus, 2) treatment with MK801 (a NMDA receptor antagonist) but not with tranexamic acid (a plasmin inhibitor) canceled the effect of rt-PA on BDNF levels. The second study exhibits that 1) neurological recovery was higher in the patients receiving rt-PA, 2) treatment with rt-PA increases serum BDNF at D1 and D7 in patients, but does not change the blood BDNF levels in animals, 3) BDNF levels are not correlated with neurological recovery but are inversely correlated to the patient cardiovascular score. In conclusion, our results suggest that rt-PA may have a protective extra-fibrinolytic effect by increasing in BDNF levels through a potentiation of glutamatergic pathway. Although rt-PA induces a better neurological recovery and increases circulating BDNF levels in stroke patients, the lack of correlation between these two parameters is not in favor of using circulating BDNF as a predictive marker of neurological recovery, but could be a reflect of the endothelium ability to synthesize BDNF
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Chan, Meanne. "Implicit measures of early-life family conditions : relationships to psychosocial characteristics and cardiovascular disease risk in adulthood." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36745.
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An implicit measure of early-life family conditions was created to help address potential biases in responses to self-reported questionnaires of early-life family environments. We investigated whether a computerized affect attribution paradigm designed to capture implicit, affective responses (anger, fear, warmth) regarding early-life family environments was a) stable over time, b) associated with self-reports of childhood family environments, c) able to predict adult psychosocial profiles (perceived social support, heightened vigilance), and d) able to predict adult cardiovascular risk (blood pressure) either alone or in conjunction with a measure of early-life socioeconomic status. Two studies were conducted to examine reliability and validity of the affect attribution paradigm (Study 1, N = 94) and associated adult psychosocial outcomes and cardiovascular risk (Study 2, N = 122). Responses on the affect attribution paradigm showed significant correlations over a 6-month period, and were moderately associated with self-reports of childhood family environments. Greater attributed negative affect about early-life family conditions predicted lower levels of current perceived social support and heightened vigilance in adulthood. Attributed negative affect also interacted with early-life socioeconomic status to marginally predict resting systolic blood pressure, such that those individuals high in early-life SES but who had implicit negative affect attributed to early-life family conditions had SBP levels that were as high as individuals low in early-life SES. Implicit measures of early-life family conditions are a useful approach for assessing the psychosocial nature of early-life environments and linking them to adult psychosocial and physiological health profiles.
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Höglund, Niklas. "Atrial fibrillation : treatment, associated conditions and quantification of symptoms." Doctoral thesis, Umeå universitet, Kardiologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-138378.
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Background: Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia. There is a need for new pharmacological treatment strategies since the current antiarrhythmic drugs have a modest efficacy and may have severe side effects. Cardioversion (CV) of AF offers an opportunity to study related conditions in sinus rhythm (SR) and during AF. Since catheter ablation of AF is a symptomatic treatment, it is important to have tools for measurement of arrhythmia-related symptoms. Aims: To evaluate the effect of atorvastatin on maintaining SR after CV of persistent AF. To assess if highsensitivity C-reactive protein (hsCRP) predicts the recurrence of AF after CV in a population randomized to treatment with either atorvastatin or placebo. To quantify the symptomatic effect of left atrial catheter ablation of AF. To assess if the restoration of SR by CV, in a population with persistent AF, affects sleep apnea. Methods: Paper I: A total of 234 patients were randomized to treatment with either high dose atorvastatin or placebo prior to CV. Paper II: In a pre-specified substudy which included 128 of the patients in study I, hsCRP was analyzed before and after CV. Paper III: Umea 22 Arrhythmia Questions (U22) is a questionnaire that quantifies paroxysmal tachycardia symptoms. A total of 105 patients underwent first-time pulmonary vein isolation and answered U22 forms at baseline and follow-up 304 (SD 121) days after ablation. Paper IV: Polysomnography was performed before and after CV in 23 patients with persistent AF scheduled for elective CV. Results: Paper I: An intention-to-treat analysis with the available data, by randomization group, showed that 57 (51%) in the atorvastatin group and 47 (42%) in the placebo group were in SR 30 days after CV (OR 1.44, 95%CI 0.85–2.44, P=0.18). Paper II: HsCRP did not significantly predict recurrence of AF at 30 days. However, after adjusting for treatment with atorvastatin, hsCRP predicted the recurrence of AF (OR 1.14, 95% CI 1.01–1.27). Six months after CV, hsCRP at randomization predicted recurrence of AF in both univariate analysis (OR 1.30, 95% CI 1.06–1.60) and in multivariate logistic regression analysis (OR 1.33, 95% CI 1.06– 1.67). Paper III: The U22 scores for well-being, arrhythmia as cause for impaired well-being, derived timeaspect score for arrhythmia, and discomfort during attack detected relevant improvements of symptoms after the ablation. U22 showed larger improvement in patients undergoing only one procedure than in patients who later underwent repeated interventions. Paper IV: Obstructive sleep apnea occurred in 17/23 patients (74%), and central sleep apnea in 6/23 patients (26%). Five patients had both obstructive and central sleep apnea. SR at follow-up was achieved in 16 patients. The obstructive apnea-hypopnea index, central apneahypopnea index, and the number of patients with obstructive or central sleep apnea did not differ before and after restoration of SR. Conclusions: Atorvastatin is not a treatment option with regards to maintaining SR after CV in patients with persistent AF. HsCRP was associated with AF recurrence 1 and 6 months after successful CV of persistent AF. U22 quantifies the symptomatic improvement after AF ablation with adequate internal consistency and construct validity. Both obstructive and central sleep apneas are highly prevalent in patients with persistent AF. Obstructive sleep apneas are unaffected by the CV of AF to SR.
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Konrad, David. "Cardiac function in experimental septic and non-septic conditions with special reference to the endothelin system /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-984-X/.
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Rich, Kelly A. "Investigating Genotype-Phenotype Correlations in TTN-related Neuromuscular and/or Cardiomyopathy Conditions." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555059134283087.
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Shafer, Sarah T. "Behavioral and biological effects of housing conditions and stress in male rats -- relevance to heart disease /." Download the thesis in PDF, 2006. http://www.lrc.usuhs.mil/dissertations/pdf/Shafer2006.pdf.
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Cirillo, Dominic J. "The effect of statin use on incident immune-mediated and infectious conditions among U.S. veterans." Diss., University of Iowa, 2008. http://ir.uiowa.edu/etd/9.
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Myers, Katherine Joyce. "Acceptability and Familiarity of Genetic Treatment Technologies: A Survey of Individuals with Sudden Arrhythmia Death Syndrome (SADS) Conditions." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1554993385165476.
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Schneider, Harald Jörn, Jens Klotsche, Bernhard Saller, Steffen Böhler, Caroline Sievers, David Pittrow, Günther Ruf, et al. "Associations of age-dependent IGF-I SDS with cardiovascular diseases and risk conditions: cross-sectional study in 6773 primary care patients." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-100953.
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Objective: We aimed at investigating the association of age-dependent IGF-I SDS with diabetes, dyslipidemia, hypertension, and heart diseases, in a large patient sample.
Background: IGF-I has been suggested to be associated with several diseases and a prognostic marker for the development of cardiovascular diseases and risk factors. The findings, though, have been inconsistent possibly due to the methodological factors.
Methods: We studied 6773 consecutive primary care patients, aged 18+ years, in a cross-sectional, epidemiological study in primary care, Diabetes Cardiovascular Risk-Evaluation: Targets and Essential Data for Commitment of Treatment study. All patients underwent a standardized clinical diagnostic and laboratory assessment. IGF-I levels were measured with an automated chemiluminescence assay system. We calculated the odds ratios (OR) for diseases in quintiles of IGF-I, and additionally analyzed the association of age-dependent IGF-I SDS with these conditions.
Results: After multiple adjustments for confounders, we found increased ORs for coronary artery disease in patients with high IGF-I. Women, but not men, with low IGF-I also showed increased ORs for coronary artery disease. Dyslipidemia was positively associated with IGF-I. Type 2 diabetes showed a curvilinear association with IGF-I SDS.
Conclusions: The findings suggest the existence of multiple and complex interactions between IGF-I and several health conditions. The complex nature of disease- and subgroup-specific associations along with the methodological factors can be held responsible for divergent findings in previous studies.
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Schneider, Harald Jörn, Jens Klotsche, Bernhard Saller, Steffen Böhler, Caroline Sievers, David Pittrow, Günther Ruf, et al. "Associations of age-dependent IGF-I SDS with cardiovascular diseases and risk conditions: cross-sectional study in 6773 primary care patients." BioScientifica, 2008. https://tud.qucosa.de/id/qucosa%3A26326.
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Objective: We aimed at investigating the association of age-dependent IGF-I SDS with diabetes, dyslipidemia, hypertension, and heart diseases, in a large patient sample.
Background: IGF-I has been suggested to be associated with several diseases and a prognostic marker for the development of cardiovascular diseases and risk factors. The findings, though, have been inconsistent possibly due to the methodological factors.
Methods: We studied 6773 consecutive primary care patients, aged 18+ years, in a cross-sectional, epidemiological study in primary care, Diabetes Cardiovascular Risk-Evaluation: Targets and Essential Data for Commitment of Treatment study. All patients underwent a standardized clinical diagnostic and laboratory assessment. IGF-I levels were measured with an automated chemiluminescence assay system. We calculated the odds ratios (OR) for diseases in quintiles of IGF-I, and additionally analyzed the association of age-dependent IGF-I SDS with these conditions.
Results: After multiple adjustments for confounders, we found increased ORs for coronary artery disease in patients with high IGF-I. Women, but not men, with low IGF-I also showed increased ORs for coronary artery disease. Dyslipidemia was positively associated with IGF-I. Type 2 diabetes showed a curvilinear association with IGF-I SDS.
Conclusions: The findings suggest the existence of multiple and complex interactions between IGF-I and several health conditions. The complex nature of disease- and subgroup-specific associations along with the methodological factors can be held responsible for divergent findings in previous studies.
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Zhou, Haiyun, and 周海韵. "Risk factors driving ambulatory care sensitive conditions hospitalisation among elderly with chronic obstructive pulmonarydisease or heart disease." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47055819.
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Kyriakidou, Despina. "Play integrated in physiotherapyy for children with chronic health conditions : A systematic literature review." Thesis, Högskolan för lärande och kommunikation, Högskolan i Jönköping, HLK, CHILD, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-30454.
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Background: Play is the child’s natural world. According to psychoanalytical studies, play has an important role in children’s development, and the absence of play during a child’s life could lead to severe pathological implications. Based on this theory and being aware that physiotherapy treatment programs could be long lasting, tiresome and lacking motivation for children, this literature review presents a perspective regarding the integration of play within physiotherapy programs and examines the physical and emotional outcomes during this integration. Aim: To investigate the outcomes of integrating play in physiotherapy for children with chronic health conditions. Method: The research strategy for this review was a thorough search of peer-reviewed articles in the databases CINAHL and AMED which include articles from the fields of allied and complementary medicine, as well as the database Scope Med. Participants were children with chronic health conditions, ranging from 2-18 years old. In the term ‘play’ virtual reality and video game activities were included due to the lack of research. In addition, articles from a previous literature review conducted by the author were also included in the present paper. Results: The focus of researchers on children with CP and the lack of evidence for children with other health conditions, the persistence of physiotherapists to assess mainly physical outcomes and not emotional needs of children, and the measurement tools used for this purpose are presented. Conclusions: For children with chronic health conditions who attend physiotherapy sessions, play could serve as a mediate and an appropriate developmental approach in order to achieve physical and emotional changes. There is a need for physiotherapists to balance physical and emotional needs, and have a more ‘human’ relationship, rather than a ‘bodily’ - strict professional relationship with children. Although the information presented in this review is not considered as sufficient to draw conclusions, it could serve as a first step for researchers to study this integration in greater depth, and to focus on children with conditions other than CP.
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Meliala, Andreanyta 1971. "Dietary phytoestrogens and hormone-related health conditions in men and women." Monash University, Monash Asia Institute, 2002. http://arrow.monash.edu.au/hdl/1959.1/8504.
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Hicks, Jason Matthew Tory. "The regulation of the cardiovascular system of red-eared sliders (Trachemys scripta) acclimated to either 5 or 22 degrees C under normoxic or anoxic conditions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq24153.pdf.
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Govind, Satish C. "Myocardial Effects of Type 2 Diabetes, Co-morbidities, and Changing Loading Conditions : a Clinical Study by Tissue Velocity Echocardiography." Doctoral thesis, Stockholm : Skolan för teknik och hälsa, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4359.
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Erskine, Nathaniel A. K. "Barriers to Healthcare Access and Patient Outcomes After a Hospitalization for an Acute Coronary Syndrome and Other Acute Conditions." eScholarship@UMMS, 2017. https://escholarship.umassmed.edu/gsbs_diss/930.
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Background: Guideline-concordant therapies for survivors of an acute coronary syndrome (ACS) hospitalization require healthcare access, something that millions of Americans lack.
Methods and Results: Using data from a prospective cohort study of over 2,000 survivors of a hospitalization for an ACS in central Massachusetts and Georgia from 2011 to 2013, the first two aims of this thesis sought to identify the post-discharge consequences for survival and health status of having: 1) financial barriers to healthcare, 2) no usual source of care, and 3) transportation barriers. We found that patients lacking a usual source of care and having a transportation barrier were more likely to have died within two years following hospital discharge compared to those without such barriers. Also, patients with financial barriers to healthcare were more likely to experience clinically meaningful declines in physical and mental health-related quality of life over the six months after hospital discharge. The third aim sought to better understand factors influencing the success of care transitions home after an unplanned hospitalization through a qualitative study of 22 patients. Participants described how adequate healthcare access, particularly having insurance and transportation to clinical appointments, facilitated the receipt of follow-up care and adherence to treatments.
Conclusions: Limitations in healthcare access may contribute to poorer survival, health-related quality of life, and survival. Additional research is needed to identify interventions to improve healthcare access and test whether improved access leads to better patient outcomes.
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Jimenez-Mejia, Jorge Hernan. "The loading and function of the mitral valve under normal, pathological and repair conditions : an in vitro study /." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-11102006-003456/.
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Thesis (Ph. D.)--Biomedical Engineering, Georgia Institute of Technology, 2007.Ajit Yoganathan, Committee Chair ; Thomas Vassiliades, Committee Member ; Joseph Gorman, Committee Member ; Marc Levenston, Committee Member ; John N. Oshinski, Committee Member.
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Van, Vuuren Annemari. "The association between influenza vaccination and hospitalization rates of respiratory and cardiovascular conditions among elderly members of a private medical scheme during the winter season of 2004 in South Africa." Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-04302009-134441.
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Fitzgibbons, Timothy P. "Role of Perivascular and Visceral Adipose Tissues in Murine Models of Obesity and Atherosclerosis: A Dissertation." eScholarship@UMMS, 2012. https://escholarship.umassmed.edu/gsbs_diss/619.
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Expansion of visceral adipose tissue correlates with the metabolic syndrome and increased cardiovascular risk. Hypertrophied visceral fat becomes inflamed, causing increased lipolysis, decreased triglyceride storage, and lipotoxicity in skeletal muscle and liver resulting in insulin resistance. Perivascular adipose tissue is a normal component of the adventitia of arteries in humans and animals. Whether or not perivascular adipose also becomes inflamed in obesity is an important question, as this may be an additional, direct mechanism by which obesity causes vascular inflammation and disease.
Thus, for the first part of my thesis, we asked the question: does perivascular adipose in mice become inflamed with high fat feeding? In contrast to visceral adipose, macrophage gene expression was not increased in perivascular adipose in response to high fat diet, and this correlated with reduced F480 antigen positive cells as seen by immunohistochemistry and flow cytometry. Interestingly, perivascular adipose surrounding the thoracic aorta was similar to brown adipose tissue, a highly thermogenic fat depot, as shown by histology and DNA microarrays. Moreover, inter-scapular brown adipose was also resistant to diet induced inflammation in comparison to visceral adipose. These findings suggest that brown adipose in the perivascular niche may serve to protect the vasculature from diet induced inflammation, or from cold exposure, or both; whether or not brown perivascular adipose tissue exists in humans has yet to be determined.
In the second part of my thesis, we evaluated the role of perivascular adipose tissue in the apolipoprotein E knockout mouse, which exhibits severe hyperlipidemia and atherosclerosis, but is resistant to diet induced obesity and glucose intolerance. We tested the hypothesis that in this model of severe atherosclerosis, inflammation of perivascular adipose does occur. However, we were surprised to find that macrophage specific gene expression, as determined by either microarray analysis or quantitative polymerase chain reaction, was not increased in either the perivascular or the visceral adipose of high fat diet fed apolipoprotein E knockout mice. While the visceral adipose of wild type mice had extensive alterations in gene expression in response to high fat diet, in particular, enrichment of inflammatory gene expression and broad down regulation of peroxisome proliferator activated receptor gamma target genes, apolipoprotein E knockout visceral adipose did not. Importantly, the apolipoprotein E knockout visceral adipose instead showed increased expression of genes encoding enzymes in fatty acid oxidation pathways. High fat diet fed apolipoprotein E knockout visceral adipose was also characterized by smaller adipocyte size.
We conclude that, 1) inflammation in thoracic perivascular adipose does not occur in conjunction with diet induced obesity in normal animals nor with atherosclerosis in apolipoprotein E knockout mice, 2) thoracic perivascular adipose tissue is essentially identical to brown adipose tissue in mice, thus potentially protecting the vasculature from the cold, and 3) apolipoprotein E knockout mice remain lean on a high fat diet, despite hyperlipidemia and atherosclerosis, and the decreased adiposity correlates with decreased adipocyte size and adipose inflammation but increased oxidation of fatty acids. Consistent with previous work showing apolipoprotein E controls adipocyte uptake and deposition of triglyceride, its absence prevents adipocyte hypertrophy and resultant inflammation of visceral adipose tissue. Thus limiting adipocyte acquisition of fatty acids may be advantageous, provided that compensatory mechanisms to prevent sustained hyperlipidemia and peripheral organ lipotoxicity can be activated.
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McManus, David D. "Incidence, prognosis, and factors associated with cardiac arrest in patients hospitalized with acute coronary syndromes (the GRACE Registry): A master's thesis." eScholarship@UMMS, 2012. https://escholarship.umassmed.edu/gsbs_diss/593.
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Objectives: Contemporary data are lacking with respect to the incidence rates of, factors associated with, and impact of cardiac arrest from ventricular fibrillation or tachycardia (VF-CA) on hospital survival in patients admitted with an acute coronary syndrome (ACS). The objectives of this multinational study were to characterize trends in the magnitude of in-hospital VF-CA complicating an ACS and describe its impact over time on hospital prognosis.
Methods: The study population consisted of 59,161 patients enrolled in the Global Registry of Acute Coronary Events Study between 2000 and 2007. Overall, 3,618 patients (6.2%) developed VF-CA during their hospitalization for an ACS. Incidence rates of VF-CA declined over time, albeit in an inconsistent manner. Patients who experienced VF-CA were on average older and had a greater burden of cardiovascular disease, yet were less likely to receive evidence-based cardiac therapies than patients in whom VF-CA did not occur. Hospital death rates were 55.3% and 1.5% in patients with and without VF-CA, respectively. There was a greater than 50% decline in the hospital death rates associated with VF-CA during the years under study. Patients with a VF-CA occurring after 48 hours were at especially high risk for dying during hospitalization (82.8%).
Conclusions: Despite reductions in the magnitude of, and short-term mortality from, VF-CA between 2000 and 2007, VF-CA continues to exert a significant adverse effect on survival among patients hospitalized with an ACS. Opportunities exist to improve the identification and treatment of ACS patients at risk for VF-CA to reduce the incidence of, and mortality from, this serious arrhythmic disturbance.
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Boulet-Le, Gouar Lysiane. "Etude de la voie catabolique du tryptophane dans différentes conditions pathologiques : exemple de la phénylcétonurie et perspectives dans les maladies cardiovasculaires Is tryptophan metabolism involved in sleep apnea-relatedcardiovascular co-morbidities and cancer progression? Neuropathology of Kynurenine Pathway of Tryptophan Metabolism Simultaneous determination of tryptophan and 8 metabolites in humanplasma by liquid chromatography/tandem mass spectrometry." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALV040.
Full textAbstract:
Le métabolisme du tryptophane (Trp) a été investigué dans différentes pathologies, incluant les maladies cardiovasculaires, la cancérologie et les maladies neurodégénératives. Le Trp, acide aminé essentiel, est catabolisé en périphérie et au niveau central selon 2 voies : celle des kynurénines, quantitativement majoritaire et impliquée dans les cardiopathies et la tolérance immune, et celle de la sérotonine, connue pour son implication dans la dépression et le sommeil. Dans le cadre de ce travail, nous nous sommes intéressés à l’implication de cette voie métabolique dans la phénylcétonurie (PCU) et les maladies cardiovasculaires.Dans la première partie de ce travail, nous avons mis au point une technique analytique de dosage de 9 métabolites de la voie du Trp, incluant ses 2 voies cataboliques. La méthode proposée, en HPLC-MS/MS, est fiable, reproductible, peu coûteuse, avec un processus pré-analytique simple et une durée d’analyse de 15 min. Ses critères sont conformes aux exigences du laboratoire selon les recommandations de la norme NF EN ISO 15189.Dans la deuxième partie, nous nous sommes intéressés au métabolisme du Trp dans la phénylcétonurie (PCU ; OMIM 261600). Cette maladie, due à un déficit de la phénylalanine hydroxylase hépatique (PAH ; EC 1.14.16.1), entraine une accumulation de phénylalanine (Phe) associée à un déficit en tyrosine. Cette pathologie, causant principalement un profond retard mental (QI < 50), est traitable grâce à l’instauration le plus précocement possible d’un régime restreint en Phe.Plusieurs éléments rapprochent le métabolisme du Trp de celui de la Phe, que ce soient les transporteurs, cofacteurs et enzyme chaperone communs, ou les inhibitions de l’une des voies par des métabolites de l’autre voie. De plus, certains adultes atteints de PCU présentent des dysfonctions neuropsychologiques inexpliquées par leur concentration de Phe sanguine, ce qui pourrait être dû à des modifications de la voie métabolique du Trp, plusieurs kynurénines possédant des propriétés neuroactives.Nous avons mis en évidence une modification du métabolisme du Trp dans une population phénylcétonurique adulte française (n=151 patients), avec en particulier une diminution des concentrations sanguines de kynurénine (KYN) et d’acide 3-hydroxykynurénique (3HK) par rapport à notre population de référence (p-value < 0.0001), ces résultats étant modulés par le type de régime suivi.La troisième partie de notre travail a consisté en l’évaluation du métabolisme du Trp dans le contexte des maladies cardiovasculaires. La prévention de ces pathologies est un enjeu de santé publique majeur, et se base sur la maitrise des facteurs de risque, dont le syndrome d’apnées obstructives du sommeil (SAOS) qui touche 6 à 17% des adultes à travers le monde. Ce syndrome se caractérise par un collapsus pharyngé partiel ou total, une fragmentation du sommeil et une augmentation des efforts respiratoires et donc des séquences d’hypoxie – réoxygénations (hypoxie intermittente) responsables d’une inflammation de bas grade. Plusieurs études explorant les maladies cardiovasculaires et le métabolisme du Trp ont été publiées récemment, mais très peu apportaient un lien mécanistique. Nous présentons ici les prochaines études cliniques et pré-cliniques que nous souhaitons mener dans ce domaine, afin de caractériser les modifications du métabolisme du Trp dans le SAOS traité ou non, mais également lors de l’hypoxie intermittente (modèle animal du SAOS) ou lors d’un réentrainement à l’effort.Il est à présent évident que la voie métabolique du Trp est impliquée dans différentes conditions pathologiques. Nous avons mis en évidence lors de ce travail ses modifications dans la PCU. L’impact physiopathologique des modifications observées reste cependant à explorer dans de nombreuses pathologiesTryptophan (Trp) metabolism was investigated in various pathology, including cardiovascular diseases, cancerology and neurodegenerative diseases. Trp, an essential aminoacid, is catabolized into two major pathways: kynurenine (KYN) pathway represents 98% of Trp catabolism and is involved in cardiopathy and immune tolerance, as serotonin (5HT) pathway is implicated in depression and sleep. In this work, we have studied Trp pathway in phenylketonuria (PKU) and cardiovascular diseases.Firstly, we developed a simple method for quantification of Trp and 8 of its metabolites, involved in both KYN and 5HT pathways, using liquid chromatography coupled to tandem mass spectrometry. This method, with a quick chromatographic runtime (15 min) and simple sample preparation, has been validated according to NF EN ISO 15189 criteria.Secondly, we explored Trp metabolism in phenylketonuria (OMIM 261600), a pathology caused by deficiency of phenylalanine hydroxylase enzyme (EC 1.14.16.1), that catalyses hydroxylation of phenylalanine (Phe) to tyrosine. Early low-Phe diet treatment, results in the prevention of severe mental retardation (IQ < 50) seen in untreated PKU patients.Many similarities between Trp and Phe metabolisms exist: transporters, cofactor and chaperone enzyme, and inhibition of one pathway by metabolites of the other pathway. As some of these metabolites have neuroactive properties, they should be considered in neurological impairment seen in this pathology and not totally explained by blood Phe concentrations.We assessed here a change of Trp metabolism in 151 adult PKU patients, with diminution of plasmatic concentrations of KYN and 3-hydroxykynurenic acid (3HK) in PKU patients compared to general population (P < .0001). These modifications were modified by diet type.In third line, we evaluated Trp metabolism in cardiovascular diseases. Prevention of these diseases representes a serious public health issue, based on diminution of co-morbidities like obstructive sleep apnoea (OSA). This syndrome affects 6-17% of adults worldwide, and is characterized by complete or partial pharyngeal collapse, sleep fragmentation and increased respiratory efforts, resulting in intermittent hypoxia and low-grade inflammation. Recent studies have explored Trp metabolism in cardiovascular diseases, but mainly in epidemiologic studies. We highlighted here clinical and preclinical studies that we will conducted in this field, in the way to characterized Trp modification in treated or untreated OSA, intermittent hypoxia (animal model of OSA) and exercise training.Trp metabolism is clearly involved in various pathological conditions. In this work, we have highlighted its modification in PKU. Physiopathological impact of these modifications have to been explored in various pathologies
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Awad, Hamza H. "Use of Multinational Registries to Assess and Compare Outcomes of Patients with an Acute Coronary Syndrome: A Dissertation." eScholarship@UMMS, 2011. https://escholarship.umassmed.edu/gsbs_diss/546.
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Background Acute coronary syndromes (ACS) are a major cause of mortality and morbidity in the developed world. By 2020, ACS will be the leading cause of morbidity and mortality worldwide, largely due to substantial increases in ACS burden in developing countries. The developing world has been under-represented in international ACS registries. The Arabian Gulf area is a part of the developing world where little is known about the epidemiology of ACS. The first aim of the dissertation is to compare ACS patient characteristics, current practice patterns, and in-hospital outcomes in the Arabian Gulf area to a large multinational sample. Patients with an ACS suffer numerous clinical complications that worsen their prognosis. Cardiogenic shock (CS) is the most serious complication of ACS and the leading cause of in-hospital death. Despite advances in therapies; CS hospital mortality rates continue to exceed 50%. The second aim of the dissertation is to describe the characteristics of patients presenting with ACS complicated by cardiogenic shock, their management, and outcomes in a large multinational sample.
In recent years, ACS has been increasingly affecting younger patients. While marked age-related differences have been observed in the risk of developing as well as the prognosis of ACS, few studies however examined time trends in the epidemiology of ACS in young adult patients. The third aim of the dissertation is to examine trends in frequency rates, patient characteristics, treatment practices, and outcomes in young adults hospitalized with an ACS.
Methods Data from two large multinational registries of patients hospitalized with an ACS were used for this investigation. Nearly 65,000 patients were enrolled in the Global Registry of Acute Coronary Events (GRACE) between 2000 and 2007, while 6,700 patients participated in the Gulf Registry of Acute Coronary Events (Gulf RACE) in 2007.
Results Aim1: Patients in Gulf RACE were significantly younger and were more likely to be male, diabetic, and smoke Compared to GRACE. Patients in Gulf RACE were less likely to receive evidence based therapies. Short-term mortality rates were comparable between the two patient cohorts. Aim2: Compared to patients with no CS, patients with CS were more likely to be older, female, have a history of diabetes, and heart failure. Patients with CS were less likely to receive effective cardiac catheterization and adjunctive cardiac medications. In-hospital case-fatality rate of patients with CS were 59.4%. While in-hospital mortality declines over the study period, incidence rates only showed minor declines. Aim2: Baseline characteristics of patients < 55 years of age did not significantly change, while the use of evidence based therapies increased significantly during the years under study. Rates of short-term adverse outcomes and mortality significantly declined over time.
Conclusions We observed marked regional differences in the risk profile, clinical management, and outcomes of patients with an ACS internationally compared to the Arab Middle East. Despite the encouraging trends in the use of evidence based therapies which have likely contributed to the improving trends in the prognosis of ACS, rates of development of ACS, as well as mortality due to ACS complications, remain high.
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Chueh, Juyu. "Mechanical Flow Restoration in Acute Ischemic Stroke: A Model System of Cerebrovascular Occlusion: A Dissertation." eScholarship@UMMS, 2010. https://escholarship.umassmed.edu/gsbs_diss/493.
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Stroke is the third most common cause of death and a leading cause of disability in the United States. The existing treatments of acute ischemic stroke (AIS) involve pharmaceutical thrombolytic therapy and/or mechanical thrombectomy. The Food and Drug Administration (FDA)-approved recombinant tissue plasminogen activator (tPA) administration for treatment of stroke is efficacious, but has a short treatment time window and is associated with a risk of symptomatic hemorrhage. Other than tPA, the Mechanical Embolus Removal in Cerebral Ischemia (MERCI) retriever system and the Penumbra Aspiration system are both approved by the FDA for retrieval of thromboemboli in AIS patients. However, the previous clinical studies have shown that the recanalization rate of the MERCI system and the clinical outcome of the Penumbra system are not optimal. To identify the variables which could affect the performance of the thrombectomy devices, much effort has been devoted to evaluate thrombectomy devices in model systems, both in vivo and in vitro, of vascular occlusion. The goal of this study is to establish a physiologically realistic, in vitro model system for the preclinical assessment of mechanical thrombectomy devices.
In this study, the model system of cerebrovascular occlusion was mainly composed of a human vascular replica, an embolus analogue (EA), and a simulated physiologic mock circulation system. The human vascular replica represents the geometry of the internal carotid artery (ICA)/middle cerebral artery (MCA) that is derived from image data in a population of patients. The features of the vasculature were characterized in terms of average curvature (AC), diameter, and length, and were used to determine the representative model. A batch manufacturing was developed to prepare the silicone replica.
The EA is a much neglected component of model systems currently. To address this limitation, extensive mechanical characterization of commonly used EAs was performed. Importantly, the properties of the EAs were compared to specimens extracted from patients. In the preliminary tests of our model system, we selected a bovine EA with stiffness similar to the thrombi retrieved from the atherosclerotic plaques. This EA was used to create an occlusion in the aforesaid replica. The thrombectomy devices tested included the MERCI L5 Retriever, Penumbra system 054, Enterprise stent, and an ultrasound waveguide device. The primary efficacy endpoint was the amount of blood flow restored, and the primary safety endpoint was an analysis of clot fragments generated and their size distribution.
A physiologically realistic model system of cerebrovascular occlusion was successfully built and applied for preclinical evaluation of thrombectomy devices. The recanalization rate of the thrombectomy device was related to the ability of the device to capture the EA during the removal of the device and the geometry of the cerebrovasculature. The risk of the embolic shower was influenced by the mechanical properties of the EA and the design of the thrombectomy device.
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Galil, Arise Garcia de Siqueira. "Influência do uso do tabaco em população com múltiplas condições crônicas." Universidade Federal de Juiz de Fora (UFJF), 2016. https://repositorio.ufjf.br/jspui/handle/ufjf/3695.
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O tabagismo representa um fator de risco para o desenvolvimento de complicações de doenças crônicas não transmissíveis, sendo classificado como uma delas e potencializador de outras condições semelhantes. Abordar tabagismo é intervenção custo-efetivo, em todos os níveis de atenção, prevenindo agravos, reduzindo tanto complicações quanto mortalidade cardiovascular e global. Para a população de alto risco cardiovascular (especialmente hipertensa, diabética e com doença renal crônica), com comorbidades presentes, parar de fumar pode ser a melhor intervenção a ser realizada. Em todas as intervenções que visem ampliar o alcance da cessação do tabaco, deve-se entender melhor o perfil dos fumantes de forma detalhada, e assim, traçar de forma efetiva, planos estratégicos para atenção individualizada e melhores resultados. Objetivos: Em usuários com múltiplas condições crônicas de alto e muito alto risco cardiovascular, identificar, conforme o uso do tabaco: 1. O perfil psicossocial, indicadores clínicos, metabólicos e comorbidades associadas; 2. As associações deste perfil de acordo com o uso do tabaco; 3. Avaliar temporalmente, num seguimento de 12 meses, indicadores clínicos (especialmente desfechos cardiovasculares e progressão da doença renal), segundo o uso do tabaco. Métodos: Estudo transversal, realizado no Centro HIPERDIA Minas Juiz de Fora, Brasil, que administra os pacientes com alto risco cardiovascular, hipertensão arterial, diabetes mellitus e doença renal crônica. Resultados: Dos 1558 participantes, 12% eram fumantes; 41% ex-fumantes e 47% nunca fumaram. Na análise univariada, tabagismo atual foi associado com sexo, idade, atividade física, consumo de álcool, sintomas depressivos, excesso de peso, e aterosclerose. Nas análises multinomiais, várias doenças crônicas foram associadas com o uso atual ou anterior do tabaco; doença pulmonar obstrutiva cônica e doença aterosclerótica foram mais prevalentes entre os pacientes que eram fumantes. Não houve diferenças estatísticas significativas na avaliação longitudinal de desfechos clínicos ou velocidade da filtração glomerular, segundo o uso do tabaco. Conclusão: O tabagismo foi tão prevalente na populacao estudada quanto na população geral. Fumantes apresentavam pior perfil clínico comparado aos exfumantes ou aos que nunca fumaram. O apoio à cessação do tabagismo pode render benefícios consideráveis, aliado à redução de custos de cuidados com a saúde, especialmente, em população com múltiplas condições crônicas de alto risco cardiovascular.
Smoking is a risk factor for the development of complications of chronic non communicable diseases and is classified as one potentiator and other similar conditions. Addressing tobacco use is cost-effective intervention at all levels of care, preventing diseases, reducing both complications as cardiovascular and overall mortality. For people at high cardiovascular risk (especially hypertension, diabetes and chronic kidney disease), with co-morbidities, smoking cessation may be the best intervention to be performed. In all interventions aimed at increasing the scope of tobacco cessation, should better understand the profile of smokers in detail, and thus draw effectively, strategic plans for individualized attention and better results. Aims: In users with multiple chronic conditions of high and very high cardiovascular risk, identify as tobacco use: 1. The psychosocial profile, clinical indicators, metabolic and associated comorbidities; 2. Associations of the profile according to the use of tobacco; 3. Evaluate temporally following a 12 month clinical indicators (especially cardiovascular outcomes and renal disease progression), according tobacco use. Methods: Cross-sectional study conducted in HIPERDIA Center Juiz de Fora Minas Gerais, Brazil, which manages patients with high cardiovascular risk, hypertension, diabetes mellitus and chronic kidney disease. Results: Of the 1558 participants, 12% were smokers; 41% former smokers and 47% had never smoked. In univariate analysis, current smoking was associated with sex, age, physical activity, alcohol consumption, depressive symptoms, overweight, and atherosclerosis. In multinomial analysis, several chronic diseases were associated with current or previous use of tobacco; chronic obstructive pulmonary disease and atherosclerosis were more prevalent among patients who were smokers. There were no statistically significant differences in the longitudinal evaluation of clinical outcomes or glomerular filtration rate, according to tobacco use. Conclusion: Smoking was so prevalent in the population studied as the general population. Smokers had poorer clinical profile compared to former smokers or those who never smoked. Support for smoking cessation can yield considerable benefits, combined with the reduction of care costs to health, especially in people with multiple chronic conditions and high cardiovascular risk.
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Rocheleau, Jessica Marie. "Effect of KCNE1 and KCNE3 Accessory Subunits on KCNQ1 Potassium Channel Function: A Dissertation." eScholarship@UMMS, 2008. https://escholarship.umassmed.edu/gsbs_diss/397.
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The KCNE1 and KCNE3 type I transmembrane-spanning β-subunits assemble with the KCNQ1 voltage-gated K+ channel to afford membrane-embedded complexes with dramatically different properties. Assembly with KCNE1 produces the very slowly activating and deactivating IKs current that shapes the repolarization phase of cardiac action potentials. Genetic mutations in KCNQ1 or KCNE1 that reduce IKs current cause long QT syndrome and predispose affected individuals to potentially fatal cardiac arrhythmias. In contrast, complexes formed between KCNQ1 and KCNE3 produce rapidly activating and mostly voltage-independent currents, properties that are essential for function in K+ recycling and Cl−secretion in gastrointestinal epithelia.
This thesis addresses how these two homologous accessory peptides impart their distinctive effects on KCNQ1 channel gating by examining two important protein regions: 1) a conserved C-terminal motif in the β-subunits themselves, and 2) the voltage sensing domain of KCNQ1 channels.
Sequences in both the transmembrane domain and C-terminus of KCNE1 and KCNE3 have been identified as contributing to the divergent modulatory effects that these β-subunits exert. The homology of transmembrane-abutting C-terminal residues within the KCNE family and the presence of long QT-causing mutations in this region highlight its importance. A bipartite model of modulation was proposed that suggests the transmembrane domain of KCNE1 is passive, allowing the C-terminal domain to control modulation. Chapter II builds on this model by investigating the effect of mutating specific amino acids in the KCNE1 C-terminal domain. Point mutants that produce ‘high impact’ perturbations in gating were shown to cluster in a periodic fashion, suggesting an alpha-helical secondary structure that is kinked by a conserved proline residue and interacts with the Q1 channel complex.
In Chapter III, the voltage sensing domain of Q1 channels is examined in the presence of either KCNE1 or KCNE3. To determine the influence of these two peptides on voltage sensing, the position of the S4 voltage sensor was monitored using cysteine accessibility experiments. In the slowly opening KCNQ1/KCNE1 complexes, voltage sensor activation appears to occur much faster than the onset of current, suggesting that slow channel activation is not due to slowly moving voltage sensors. KCNE3, on the other hand, shifts the voltage sensor equilibrium to favor the active state, producing open channels even at negative voltages.
Taken together, these findings provide mechanistic detail to illustrate how two homologous peptides radically alter the gating properties of the same K+ channel and present a structural scaffold to map protein-protein interactions.
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Mandigout, Stéphane. "Effet de l'entraînement en endurance sur le système cardiovasculaire de filles et de garçons prépubères." Orléans, 2001. http://www.theses.fr/2001ORLE2072.
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L'objectif de ce travail est d'évaluer l'influence d'un programme d'entraînement en endurance sur 1-le VO2max déterminé par méthode directe à l'issue d'un exercice triangulaire réalisé sur ergocycle, 2-les caractéristiques morphologiques et fonctionnelles du VG déterminé au repos par échocardiographie-Doppler, 3-les réponses hémodynamiques à l'exercice sous-maximal et maximal évaluées par la méthode Doppler, et 4-sur la variabilité de la FC calculée au moyen d'une analyse temporelle et fréquentielle d'un enregistrement-Holter chez l'enfant prépubère. La population d'étude est composée de 132 garçons et filles âgés de 10-11ans. 65 sujets ont bénéficié du programme d'entraînement et constituent le groupe expérimental et 67 sujets n'ayant pas bénéficier du programme constituent le groupe contrôle. Ce travail a permis de mettre en évidence qu'un programme d'entraînement de 13 semaines organisé sur la base de 3 sessions par semaine avec 25-35min de travail effectif réalisé à une intensité supérieure à 80% de la fréquence cardiaque maximale, améliore le VO2max de filles et de garçons prépubères. Quel que soit le sexe, le volume d'éjection systolique(VES) maximale semble être le seul facteur responsable de l'augmentation de VO2max induite par l'entraînement. De plus, les variables influençant l'augmentation du VES de repos après entraînement (augmentation des diamètres internes du ventricule gauche, amélioration de certains indices de la fonction diastolique, diminution de la post-charge) pourraient être critiques dans le déterminisme du VESmax et donc de VO2max.
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Marin-Couture, Elisa. "Le phénotype "fit-actif" : pour mieux refléter les bienfaits de la participation à l'activité physique vigoureuse au cours de la vie sur la santé." Master's thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/67569.
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Les bienfaits d’une pratique régulière de l’activité physique sur la composition corporelle et ses complications métaboliques sont bien établis dans la littérature. Cependant, les interventions cliniques prônant une perte de poids par la pratique d’activité physique seule ne procureraient pas les bénéfices recherchés sur la composition corporelle et la santé métabolique contrairement à une intervention de saines habitudes alimentaires prescrite à elle seule. Cela soulève la question à savoir dans quelle mesure le stimulus de l’exercice a été suffisamment caractérisé pour refléter l’empreinte à long terme d’un mode de vie actif sur le risque de développer l’obésité et les complications métaboliques associées. Ce mémoire documente ce problème en résumant les évidences et en présentant des données montrant qu’une classification basée sur la capacité aérobie et la pratique d’activité physique permettent de mieux refléter l’impact d’une pratique d’activité physique vigoureuse tout au long de la vie sur la composition corporelle et la santé métabolique. En outre, nous renforçons la pertinence de cette classification en présentant des données provenant de l’Étude des familles de Québec (QFS) comparant les individus « fit-actifs » à ceux « unfit-inactifs ». Les résultats des deux sexes montrent que les individus « fitactifs » présentent des profils morphologique et métabolique beaucoup plus favorables que ceux des individus « unfit-inactifs ». Les bénéfices semblent provenir davantage des variations de condition cardiorespiratoire que celles de la pratique d’activité physique. En résumé, ces observations suggèrent que les bénéfices d’une pratique d’activité physique vigoureuse à long terme seraient bien représentés par une classification basée sur la capacité aérobie et la pratique d’activité physique rapportée.Regular physical activity participation has been recognized over time as an essential component of a lifestyle contributing to the prevention of obesity and non-communicable diseases. Recently, the emphasis on sedentary behaviors and physical inactivity as additional factors, independent of physical activity practice, has to some extent confirmed the relevance to encourage regular physical activity habits in the prevention and management of obesity. This optimistic vision is however toned down by some clinical interventions that demonstrate that the inclusion of a physical activity component in a weight reducing program is not producing substantial additional benefits on body composition and metabolic health compared to when a healthy diet is prescribed alone. This raises the question as to which extent the exercise stimulus has been adequately characterized to reflect the long-term print of an active lifestyle on the risk to develop obesity and related metabolic complications. This thesis documents this issue by summarizing evidences and presenting relevant data showing that a classification based on aerobic fitness and physical activity practice provides indications of greater impact of a lifelong vigorous physical activity practice compared to what may be anticipated from existing literature. Furthermore, we reinforce the pertinence of this classification by presenting relevant data from the Quebec Family Study to compare the fit-active to the unfit-inactive individuals. For both sexes, fit-active individuals displayed much more favorable morphological and metabolic profiles than their unfit-inactive counterparts. The fitness variations of the profile seem to generate more benefits than the physical activity practice in the profile. In summary, these observations suggest that the benefits of a lifelong physical activity practice may well be reflected by a classification based on both fitness and reported physical activity practice.
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Fabayo, Oluwayomi. "Perceived Cardiovascular Risk Among West Africa Immigrants in DeKalb County, Georgia." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5328.
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West African immigrants appear to carry a heavier burden of hypertensive heart disease than the native-born African Americans in the United States. In this study, I used the socioecological model theory as a guide to examine the association between perceived stress, length of stay in United States, smoking status, housing conditions, and the risk of hypertensive heart disease among West African immigrants, ages 18 - 54 years in DeKalb County, Georgia. In this quantitative, cross-sectional design, self-reported data were collected from a sample of West African immigrant (N=107) in the DeKalb County of Georgia, using a demographic data/screening sheet and the Perceived Stress Scale. Multivariate logistic regression analysis was used to determine the association between hypertensive heart disease and perceived stress, smoking status, length of stay in the United States, and housing condition, having adjusted for the modifying variables age and education. Results indicated that length of stay in the United States [p =.019, Phi =.331], housing condition [p=.156, R2 =.019], smoking status [p=.050, R2 =.036] and experienced perceived stress experienced [p=.312, R2=.010] are associated with risk of developing hypertensive heart disease. There was a statistically significant association between age [p=.002] and the development of hypertensive heart disease. The result of this study can contribute to positive social change by helping public health agencies to target some of the identified risk factors for hypertensive heart disease in foreign born African American population so as to mitigate the adverse health outcomes associated with hypertensive heart disease.
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DUQUE, Ivan Leonardo. "L’aptitude cardio-respiratoire chez les patients lombalgiques chroniques. : Evolution de la consommation maximale d’oxygène au cours d’un programme de restauration fonctionnelle et incidence des facteurs limitant l’effort maximal pendant les tests d’effort." Paris 13, 2010. http://www.theses.fr/2010PA132017.
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Cette étude a analysé l’évolution de l’endurance cardiovasculaire et respiratoire chez les patients lombalgiques chroniques, et l’interférence des facteurs limitant l’effort maximal pendant la mesure de la consommation maximale d’oxygène. Les tests d’effort ont été réalisés avant et après un programme de restauration fonctionnelle, comprenant un part importante de reconditionnement par l’exercice physique. Les patients ont bénéficié d’une prise en charge thérapeutique par la restauration fonctionnelle d’une durée de 6 semaines. Ils ont passé une épreuve d’effort standardisée avant et après le réentraînement. Chez 101 sujets nous avons démontré une augmentation statistiquement significative de la consommation maximale d’oxygène. Lorsque les sujets sont regroupés en fonction des critères d’atteinte de la consommation maximale d’oxygène, une augmentation significative a été observée seulement chez les sujets du groupe 1 (consommation maximale d’oxygène avant et après entraînement). Dans les trois autres groupes les critères cliniques et paracliniques interfèrent avec la réalisation des efforts maximaux. La comparaison avec un groupe de sujets sains sédentaires appariés confirme que les patients lombalgiques chronique présente un syndrome de déconditionnementThis study analyzed the evolution of the respiratory and cardiovascular endurance in patients with chronic low back pain, and interference factors limiting the maximum effort during measurement of maximal oxygen uptake. Stress tests were performed before and after a functional restoration program, including a substantial reconditioning through exercise. Patients received a therapeutic treatment for functional restoration of a period of 6 weeks. They spent a standardized exercise test before and after exercise training. In 101 subjects we demonstrated a statistically significant increase in maximal oxygen consumption. When subjects are grouped according to the criteria for attainment of maximal oxygen consumption, a significant increase was observed only in subjects in group 1 (maximal oxygen uptake before and after training). In the other three groups clinical and paraclinical interfere with achieving the maximum stresses. The comparison with a group of healthy subjects matched sedentary confirms that patients with low back pain syndrome has a chronic deconditioning
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Joulia, Fabrice. "Modifications de la fonction cardio-vasculaire associées aux conditions de ventilation en charge (normobare et hyperbare)." Aix-Marseille 2, 1992. http://www.theses.fr/1992AIX20652.
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Bauer, Michael, Rita Bauer, Tasha Glenn, Sergio Strejilevich, Jörn Conell, Martin Alda, Raffaella Ardau, et al. "Internet use by older adults with bipolar disorder: international survey results." Springer, 2018. https://tud.qucosa.de/id/qucosa%3A33426.
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Abstract
Background:
The world population is aging and the number of older adults with bipolar disorder is increasing. Digital technologies are viewed as a framework to improve care of older adults with bipolar disorder. This analysis quantifes Internet use by older adults with bipolar disorder as part of a larger survey project about information seeking.
Methods:
A paper-based survey about information seeking by patients with bipolar disorder was developed and translated into 12 languages. The survey was anonymous and completed between March 2014 and January 2016 by 1222 patients in 17 countries. All patients were diagnosed by a psychiatrist. General estimating equations were used
to account for correlated data.
Results:
Overall, 47% of older adults (age 60 years or older) used the Internet versus 87% of younger adults (less than 60 years). More education and having symptoms that interfered with regular activities increased the odds of using the Internet, while being age 60 years or older decreased the odds. Data from 187 older adults and 1021 younger adults were included in the analysis excluding missing values.
Conclusions:
Older adults with bipolar disorder use the Internet much less frequently than younger adults. Many older adults do not use the Internet, and technology tools are suitable for some but not all older adults. As more health services are only available online, and more digital tools are developed, there is concern about growing health
disparities based on age. Mental health experts should participate in determining the appropriate role for digital tools for older adults with bipolar disorder.
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Brindle, Christopher T. "Incidence and Predictor Variables of Pressure Injuries in Patients Undergoing Ventricular Assist Device and Total Artificial Heart Surgeries: An Eight-Year Retrospective Review." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/6038.
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BACKGROUND
Cardiac surgery patients have some of the highest reported incidence and prevalence of pressure injuries (PI). A growing subset of cardiac surgery include patients with end-stage heart failure who undergo ventricular assist device (VAD) or total artificial heart (TAH) surgery. The risk of PI and their natural history of development in this population are unknown and the specific risk factors for PI development remain unexplored.
OBJECTIVES
To perform a systematic review of the literature to identify the incidence and risk factors of PI development in patients undergoing VAD-TAH surgery and thereby inform study design and variables in an eight-year retrospective study of all patients undergoing VAD-TAH surgery at a large academic university medical center.
METHODS
The preferred reporting items for systematic reviews and meta-analyses or PRISMA statement guided this systematic review. Quality of evidence was determined using the Johns Hopkins Nursing Evidence-Based Practice Rating Scale. Two reviewers independently appraised manuscripts matching the eligibility criteria for study inclusion. Four databases including PubMed, CINAHL, Web of Science, Google Scholar, and hand searches of journals based on reference lists from included studies were utilized. Initial results of this primary search revealed zero studies that met inclusion and this search methodology was confirmed by medical librarian consultation. Therefore, a follow up retrospective study was necessary to identify incidence of PI in the VAD-TAH population. However, a secondary search, dropping keywords of VAD-TAH and instead focusing on studies of on-pump cardiac surgery and mixed surgical studies where cardiac surgery patients were included, was conducted to establish variables to guide a retrospective study of all VAD-TAH surgeries between 2010-2018. The retrospective study evaluated the incidence of pressure ulcers by case, patient and incidence density for each of the respective 1000 patient days during the study period. Univariate statistics are reported by four different VAD-TAH devices. Variables significant in bivariate analysis were entered in a stepwise logistic regression model.
RESULTS
In the systematic review, 312 articles were identified from the databases with eight additional articles from hand searches. Following abstract review, 208 were excluded for not meeting inclusion criteria or study quality metrics. 77 articles were read in full, with 61 excluded, leaving 16 articles for inclusion. 31 risk factors were identified for PI development in on-pump cardiac surgery patients with 11 risk factors which were identified as significant in multivariate analysis for inclusion in the retrospective study.
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Bas, Tuba. "Co– and Post–Translational N–Linked Glycosylation of Cardiac Potassium Channel Subunits: A Dissertation." eScholarship@UMMS, 2010. https://escholarship.umassmed.edu/gsbs_diss/490.
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KCNE1 (E1) peptide is the founding member of the KCNE family (1-5), which is a class of type I transmembrane ß-subunits. KCNE1 peptides assemble with and modulate the gating, ion conducting properties and pharmacology of a variety of voltage-gated K+ channel a-subunits, including KCNQ1 (Q1). Mutations that interfere with the function of either E1 and/or Q1 and disrupt the assembly and trafficking of KCNE1- KCNQ1 channel complexes give rise to diseases such as Romano-Ward (RW) and Jervell Lange Nielsen Syndrome (JLNS), two different forms of Long QT Syndrome (LQTS).
Using enzymatic deglycosylation assays, immunofluorescence techniques and quantitative cell surface labeling, we showed that KCNE1 peptides are retained in the early stages of the secretory pathway as immaturely N-linked glycosylated proteins. KCNE1 co-assembly with KCNQ1 leads to E1 progression through the secretory pathway and glycan maturation, resulting in cell surface expression.
N-linked glycosylation of some membrane proteins is critical for proper folding, co-assembly and subsequent trafficking through the biosynthetic pathway. Previous studies have shown that genetic mutations that disrupt one of the two N-linked glycosylation sites on KCNE family members lead to LQTS (T7I, KCNE1 and T8A, KCNE2) (Schulze-Bahr et al., 1997; Sesti et al., 2000a; Park et al., 2003). Having confirmed that KCNE1 proteins acquire N-linked glycans, we examined the kinetics and efficiency of N-linked glycan addition to KCNE1. We showed that KCNE1 has two distinct N-linked glycosylation sites. The N-terminal sequon is a traditional co-translational site. The internal sequon (which is only ~ 20 residues away from the N-terminal sequon) acquires N-linked glycans primarily after protein synthesis (post-translationally). Surprisingly, mutations that prevent N-glycosylation at the cotranslational site also reduce the glycosylation efficiency of post-translational glycosylation at the internal sequon, resulting in a large population of unglycosylated KCNE1 peptides that are retained in the early stages of the secretory pathway and do not reach the cell surface with their cognate K+ channel. We showed that KCNE1 post-translational N-glycosylation in the endoplasmic reticulum is a cellular mechanism that ensures E1 proteins acquire the maximal number of glycans needed for proper channel assembly and trafficking. Our findings provide a new biogenic mechanism for human disease by showing that the JLNS mutation, T7I, not only inhibits glycosylation of the N-terminal sequon, but also indirectly prevents the glycosylation of the internal sequon, giving rise to a large population of assembly incompetent hypoglycosylated KCNE1 peptides.
To further investigate the two N-linked glycosylation sites on KCNE1, we generated structure-function deletion scans of KCNE1 and performed positional glycosylation scanning mutagenesis. We examined the glycosylation pattern of glycosylation mutants in an effort to define the glycosylation window important for proper KCNE1 assembly and trafficking. Our findings suggested a nine amino acid periodicity to serve as a desirable glycosylation site and a better substrate for N-glycosylation.
Appendix II shows work on the characterization of the C-terminally HA-tagged KCNE1 protein, which was used throughout the experiments presented in Chapter II, Chapter III and Chapter IV. Analysis of the C-terminally HA-tagged KCNE1 protein revealed that in heterologous expression systems KCNE1 had an internal translational start site, a methionine at position 27. A proteolytic cleavage site was also identified at the arginine cluster spanning residues 32 through 38 bearing the two known Long QT mutations (R32H and R36H) (Splawski et al., 2000; Napolitano et al., 2005).
My work in Professor Craig C. Mello’s lab during the first four years of my graduate study is presented in Appendix I. The highly conserved Wnt/Wingless glycoproteins regulate many aspects of animal development. Wnt signaling specifies endoderm fate by controlling the fate of EMS blastomere daughters in 4-cell stage Caenorhabditis elegans embryos. A suppressor genetic screen was performed using two temperature sensitive alleles of mom-2/Wnt to identify additional regulators of the Wnt/Wingless signaling pathway during C. elegans endoderm specification. Five intragenic suppressors and three extragenic suppressors of mom-2/Wnt embryonic lethality were identified. We cloned ifg-1, eIF4G homologue, as one of the extragenic suppressors suggesting an intriguing connection between the Wnt signaling pathway and the translational machinery.
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Li, Xia. "C - Reactive Protein, Coronary Heart Disease and Ischemic Stroke in the Elderly: The Cardiovascular Health Study." VCU Scholars Compass, 2006. http://hdl.handle.net/10156/2037.
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Diaz-Zuccarini, Vanessa Alexandra Lefèvre Jacques Delgado Marisol. "Étude des conditions d'efficacité du ventricule gauche par optimisation téléonomique d'un modèle de son fonctionnement." [S.l.] : [s.n.], 2003. http://www.univ-lille1.fr/bustl-grisemine/pdf/extheses/50376-2003-287-288.
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Thèse doctorat : Productique : Automatique et Informatique industrielle : Lille 1 : 2003.N° d'ordre (Lille 1) : 3424. Pagination ajoutée entre crochets pour les annexes et la bibliographie. Bibliogr. 12 p.
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Mills, Kyly M. "'Work it out': Evaluation of a chronic condition self-management program for urban Aboriginal and Torres Strait Islander people with or at risk of cardiovascular disease." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/90737/1/Kyly_Mills_Thesis.pdf.
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This thesis evaluates a chronic condition self-management program for Aboriginal and Torres Strait Islander people in urban south-east Queensland who have or are at risk of cardiovascular disease. Outcomes showed short-term improvements for some anthropometry measures which could be a trend for improvement in other anthropometry indicators over the longer term. The program was of particular benefit for participants who had several social and emotional wellbeing conditions. The use of an Aboriginal and Torres Strait Islander conceptual framework was critical in undertaking culturally competent quantitative research in this project.
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Provost, Romain. "Adaptation cardiovasculaire de l'astronaute : en confinement et en microgravité réelle et simulée." Thesis, Tours, 2015. http://www.theses.fr/2015TOUR3307/document.
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Le présent travail de Doctorat porte sur l’adaptation et le déconditionnement cardiovasculaire chez l’astronaute en microgravité réelle prolongée, en microgravité simulée de courte durée (avec et sans contremesures par hypergravité), et en confinement de longue durée. Afin de répondre à cette thématique, 3 études expérimentales sur l’humain ont été réalisées, et de fait, ce présent travail de Doctorat se divise en 3 parties distinctes. La première est la mission « Mars 500 » qui comprend un confinement de 520 jours de 6 sujets-volontaires. La seconde est le projet « Vessel Imaging » qui comprend un vol spatial respectif de 6 mois à bord de la « Station Spatiale Internationale (ISS) » de 10 sujets-astronautes. La troisième est l’étude «Short Time Bed-Rest (STBR)» (12 sujets) qui comprend une courte période de microgravité simulée par alitement prolongé à -6° (5 jours) avec et sans l’utilisation de deux contremesures cardiovasculaires par hypergravité (continue ou intermittente)This PhD work focuses on astronaut cardiovascular adaptation and deconditioning in real prolonged microgravity, short simulated microgravity (with and without countermeasures) and long-term confinement. To answer to this topic 3 humans experimental studies have been performed, and thus the present PhD work is divided into 3 distinct parts . The first one is the mission « Mars 500 » which consists in 520-days confinement with 6 subjects-volunteers mission. The second is the project « Vessel Imaging » whitch consit in a 6-months spaceflight aboard the « International Space Station » with 10 subjects-astronauts. The third is the « Short Time Bed -Rest (STBR) » study (12 subjects) which consist in a short period of bedrest (-6°, 5 days) with and without the use of two cardiovascular countermeasures by hypergravity (continuous or intermittent)
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McKay, Caroline Mae. "The role of social structural and social contextual factors in shaping chronic disease and chronic disease risk behavior : a multilevel study of hypertension, general health status, and mental distress." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001434.
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Piquet, Lydie. "Etude par effet Doppler ultrasonore de la circulation musculaire à l'effort chez des sujets sains et pathologiques : application chez 419 sujets normaux ou porteurs de pathologies." Tours, 2000. http://www.theses.fr/2000TOUR3303.
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Objectifs : étude par Doppler ultrasonore de la réponse à l'effort de sujets sains et pathologiques (419 sujets). Etude des courbes de vitesse instantanées et moyennes au niveau de l'artère fémorale commune, au repos, et immédiatement après l'exercice, de manière à corréler les paramètres du flux sanguin avec la capacité de transfert d'O2 des poumons vers les muscles, et donc à priori avec la vitesse de récupération du sujet testé. Les enregistrements Doppler sont réalisés avec le capteur Doppler plat du Flow-Tester. A partir des enregistrements, il est possible de calculer les périodes de récupération de la vitesse du flux sanguin (PRF), de la fréquence cardiaque (PRfc) et du volume d'éjection fémoral (PRVEF). Une étude réalisée sur 50 sujets montre la bonne correspondance entre la vitesse du flux sanguin mesurée par le Flow-Tester et le débit sanguin calculé par système Duplex Echo-Doppler. Les tests ont été réalisés dans deux types de population : chez des sujets sains, sédentaires ou sportifs, nous obtenons toujours une très bonne corrélation entre les principaux paramètres ; chez 20 volontaires sains, allongement important sous β bloquants de PRF, PRVEF. En pathologie respiratoire et cardiaque ( 43 patients) il existe une excellente corrélation entre la PRF et la VO2 max. Que ce soit après exercice sous maximal ou exercice maximal. Une modélisation par systèmes compartimentaux montre le rôle des différents paramètres intervenant dans le transfert d'O2 de l'air ambiant à la cellule musculaire ainsi que le rôle de l'entraînement sur cette capacité de transfert. En conclusion, grâce à un système à effet Doppler simple, il est possible de suivre l'entraînement des sportifs, de vérifier l'efficacité d'un traitement et d'évaluer la progression de patients en réeducation.
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Chartrand, Dominic. "Adiposité viscérale et contenu en lipides du foie : contribution de la condition cardiorespiratoire." Master's thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/67223.
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En 2016, l’American Heart Association publie un rapport de prise de position sur l’importance de mesurer la condition cardiorespiratoire en pratique clinique. La capacité de cette mesure à optimiser la stratification du risque de mortalité et du risque cardiométabolique a été démontrée. Il a également été rapporté que la condition cardiorespiratoire est un plus puissant marqueur de risque de mortalité que les marqueurs traditionnels comme le cholestérol, le tabagisme et le diabète. Plusieurs études démontrent que son association négative avec les marqueurs du risque cardiométabolique est médiée par l’adiposité viscérale ou par le contenu en lipides du foie. Cependant, la contribution respective de ces dépôts lipidiques sur l’association entre la condition cardiorespiratoire et les marqueurs du risque cardiométabolique n’a jamais été étudiée. Ce projet de maîtrise vise donc à documenter la contribution respective de l’adiposité viscérale et du contenu en lipides du foie dans l’association entre la condition cardiorespiratoire et les marqueurs du risque cardiométabolique chez des femmes et des hommes sans maladie cardiovasculaire connue. Une épreuve d’effort maximal sur tapis roulant avec mesure des échanges gazeux et une résonance magnétique incluant une spectroscopie du foie ont été réalisées chez les participants (135 femmes et 177 hommes). Plusieurs marqueurs du risque cardiométabolique ont aussi été mesurés dont la glycémie et l’insulinémie lors d’un test d’hyperglycémie orale provoquée (OGTT). Les résultats démontrent que l’association négative entre la condition cardiorespiratoire et les aires sous la courbe du glucose et de l’insuline mesurées lors d’une OGTT semble attribuable aux variations concomitantes dans l’adiposité viscérale et le contenu en lipides du foie. Bien que ces travaux ne puissent pas démontrer un lien de causalité, ils soulignent qu’une bonne condition cardiorespiratoire est associée à des quantités moindres de tissu adipeux viscéral et de lipides au foie, ce qui pourrait expliquer son lien avec une bonne santé cardiométabolique.In 2016, the American Heart Association published a position statement addressing the importance of measuring cardiorespiratory fitness in clinical practice. The capacity of this measurement to significantly improve the reclassification of risk for adverse outcomes has been firmly established. It has also been demonstrated that cardiorespiratory fitness is a stronger predictor of mortality than established risk factors such as high cholesterol, smoking and type 2 diabetes. A large body of evidence has demonstrated that the negative association between cardiorespiratory fitness and cardiometabolic risk markers is mediated by visceral adiposity or liver fat content. Nonetheless, the respective contribution of these fat depots in the association between cardiorespiratory fitness and markers of cardiometabolic health has never been studied. This Master’s project therefore aims at documenting the respective contribution of visceral adiposity and liver fat content in the association between cardiorespiratory fitness and cardiometabolic risk markers in women and men without evidence of cardiovascular disease. A maximal treadmill exercise test combined with ventilatory expired gas exchange analysis as well as magnetic resonance imaging including spectroscopy of the liver were performed among 135 women and 177 men. Cardiometabolic risk markers such as plasma glucose and insulin during an oral glucose tolerance test (OGTT) were also measured. The results show that the negative association between cardiorespiratory fitness and glucose and insulin areas under the curve measured during the OGTT seems dependent of the concomitant variations in visceral adiposity and liver fat content. Although it cannot confirm causality, this work highlights the association between high cardiorespiratory fitness and low levels of visceral and hepatic fat which might in turn explain its association with good cardiometabolic health.
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Hassler, Sven. "The health condition in the Sami population of Sweden, 1961-2002 : Causes of death and incidences of cancer and cardiovascular diseases." Doctoral thesis, Umeå : Department of Public Health and Clinical Medicine, Umeå University, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-519.
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Van, Dyk A. P. "The effects of a sports vision training programme on selected visual-motor skills in a non-fatigued and fatigued cardiovascular condition." Thesis, University of the Western Cape, 2014. http://hdl.handle.net/11394/4284.
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Philosophiae Doctor - PhDThe aim of the study was to determine the effects of a sports vision training programme on peripheral awareness, eye-hand coordination, eye-body coordination, visual reaction time and visual-motor response time of physically active males when in a non-fatigued condition and when in an induced-fatigue condition that simulates levels experienced when playing field-based sports. Scheduling challenges made it necessary to use a sample of convenience rather than random sampling to divide the 49 participants into a treatment group (n=16) and a control group (n=33). A pre-test was administered according to assessment protocols for five selected visual skills performed in both a nonfatigued and fatigued condition. The treatment group participated in an eight-week visual training intervention programme. The purpose of this visual training programme was to train the five selected visual skills (peripheral awareness, eye-hand coordination, eyebody coordination, visual reaction time and visual-motor response time and to practice these skills during fatigued cardiovascular conditions. The post test was administered immediately after the intervention period. Interaction effects were found for three variables: peripheral awareness, eye-hand coordination and visual reaction time, so conclusions could be drawn only for eye-body coordination and visual-motor response time. No significant differences were found for visual-motor response time in the non-fatigued condition. It can be concluded that the sports vision training programme, as implemented in this study, resulted in a significant improvement in visual-motor response time of the treatment group as compared to the control group, when performing under fatigue conditions.
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Fournier, Tristan. "Une sociologie de la décision alimentaire : l'observance diététique chez des mangeurs hypercholesterolémiques." Thesis, Toulouse 2, 2011. http://www.theses.fr/2011TOU20033.
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Cette thèse tente d’apporter, en la sociologisant, des éléments de réponse à une question émanant du monde médical : pourquoi des individus atteints d’hypercholestérolémie et donc surexposés à des risques cardio-vasculaires ne mettent-ils pas en application les conseils diététiques formulés par leur médecin ? Trois phases d’enquête ont été menées : 1) des entretiens d’experts, dans le but d’identifier les controverses qui ont transformé l’hypercholestérolémie en un problème de santé publique majeur ; 2) des entretiens individuels et collectifs auprès de « mangeurs à risques », afin de saisir les principaux freins au suivi des règles hygiéno-diététiques prescrites et les formes de régulation sociale de la pathologie ; et 3) une enquête quantitative, avec passation de questionnaires auprès de 800 individus, ayant pour but la description socio-démographique de la population d’étude et la validation des résultats qualitatifs. Si les rapports à l’alimentation et à la santé apparaissent comme étant en partie surdéterminés par des variables sociales et culturelles, les résultats invitent surtout à resituer les individus dans leurs contextes interactionnels et familiaux. Les décisions alimentaires et les manières de faire face à cette pathologie chronique ne sont pas construites dans une perspective individuelle. Au final, l’articulation entre la sociologie de l’alimentation et les champs de la santé, du risque, de la famille et du genre a permis de renouveler la problématique de l’observance et d’ouvrir un vaste territoire de recherches sur les effets du « manger ensemble » et du « vivre ensemble ». En cela, la thèse entend contribuer à une sociologie de la décision alimentaireThis thesis attends answering a question originated from the medical world, by framing it through a sociological perspective: why do some hypercholesterolaemic individuals not comply with their doctor’s dietetic advice although being overexposed to cardiovascular risks? Three surveys were conducted: 1) some experts’ interviews, so as to identify the controversies that have led hypercholesterolaemia to be considered as a major public health problem; some in-depth interviews and a focus group with “at risk eaters”, in order to grasp the main obstacles to the dietary compliance and the forms of social regulation for the pathology; and 3) a quantitative survey, carried out by questionnaires among 800 people and developed with the aim of collecting sociodemographic data on the population, and validating the qualitative results. Notwithstanding that the relations with food and health are partly over-determined by social and cultural variables, results underlined the need to situate individuals in their interactional and family environment. Neither eating choices nor the ways to cope with this chronic pathology are constructed within an individual perspective. Connecting the sociology of food with other works from the health, risk, family and gender domains eventually enabled revitalizing the compliance issue and initiating a vast field of researches on the effects of “eating together” and “living together”. This thesis therefore intends contributing to a sociology of eating choices
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Stowell, Jeffrey Ronald. "Interactions between Basal Forebrain Cholinergic Lesions and Benzodiazepine receptor modulation on behavioral and Cardiovascular responses in a conditioned suppression paradigm /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488192119264761.
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