Made available in DSpace on 2014-06-11T19:23:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-28Bitstream added on 2014-06-13T20:11:33Z : No. of bitstreams: 1 mendes_oc_me_botfm.pdf: 471774 bytes, checksum: 85d9ae9190c29d29bbfa5997d937273b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Em razão de, em estudos que analisam a relação remodelação cardíaca e estenose aórtica supravalvar: ser importante a detecção precoce da disfunção ventricular; o método hemodinâmico ser ideal para detecção da disfunção, porém inadequado para estudos seqüenciais; a taquipnéia manifestar-se, geralmente, quando há deterioração cardíaca grave e não estar estabelecida a relação entre a capacidade funcional e a função ventricular, torna-se necessário identificar se o(s) primeiro(s) sinal(is) de intolerância ao esforço físico está(ão) relacionado(s) a disfunção ventricular. Assim, este trabalho tem como objetivos avaliar em diferentes períodos, 3, 6, 12 e 18 semanas, após indução de estenose aórtica supravalvar em ratos a: 1) função do ventrículo esquerdo em repouso e as alterações morfológicas cardíacas por meio do ecocardiograma; 2) tolerância ao esforço físico, em teste incremental em esteira; 3) relação entre a tolerância ao esforço físico e a função cardíaca determinada em repouso. Foram utilizados 37 ratos Wistar, jovens, machos divididos em dois grupos: controle operado (GC, n=13) e estenose aórtica supravalvar (GEAo, n=24). O GEAo foi submetido a cirurgia com implantação de um clipe na artéria aorta para a indução da estenose aórtica supravalvar. O GC foi submetido à mesma cirurgia, porém sem a implantação do clipe. Os animais foram mantidos com água e ração e ad libitum, em ambiente com temperatura controlada a 23°C e ciclo de luz invertido. Todos os procedimentos foram realizados no ciclo escuro, com o auxílio de iluminação fluorescente vermelha, cuja emissão de onda, por ser longa, não é percebida pelos animais. Dos 24 ratos do grupo estenose aórtica (GEAo), 10 morreram e dois apresentaram sinais de insuficiência cardíaca ao final do experimento, taquipnéia associada a derrame pleural... / Considering that, in studies analyzing the relationship between cardiac remodeling and supravalvar aortic stenosis, the early detection of ventricular dysfunction is important, the hemodynamic method is ideal to detect such dysfunction although it is inadequate for sequential studies, tachypnea is generally manifested when severe cardiac deterioration exists and that the relationship between functional capacity and ventricular function has not been established, it is necessary to identify whether the first sign(s) of exercise intolerance is(are) related to ventricular dysfunction. Hence, this study aimed at evaluating, in different periods - 3, 6, 12 and 18 weeks - after the induction of supravalvar aortic stenosis in rats, the following aspects: 1) function of the left ventricle at rest and cardiac morphological alterations by means of an echocardiogram; 2) exercise tolerance during an incremental test on a treadmill; 3) relationship between exercise tolerance and cardiac function determined at rest. Thirty-seven young male Wistar rats were used. The animals were separated into two groups: operated control (CG, n=13) and supravalvar aortic stenosis (GEAo, n=24). GEAo was submitted to surgery with the implantation of a clip on the aorta artery for induction of supravalvar aortic stenosis. GC was submitted to the same type of surgery although without clip implantation. The animals were given water and chow ad libitum and maintained in a controlledtemperature environment at 23°C and an inverted light-dark cycle. All the procedures were performed in the dark cycle by using red fluorescent illumination, whose long wave emission is not perceived by the animals. Of the 24 rats in the GEAo ten died and two presented signs of cardiac insufficiency at the end of the experiment, tachypnea associated with pleural stroke, thrombus in the left atrium and hypertrophia in the right ventricle, thus... (Complete abstract click electronic access below)

Resumo: Em razão de, em estudos que analisam a relação remodelação cardíaca e estenose aórtica supravalvar: ser importante a detecção precoce da disfunção ventricular; o método hemodinâmico ser ideal para detecção da disfunção, porém inadequado para estudos seqüenciais; a taquipnéia manifestar-se, geralmente, quando há deterioração cardíaca grave e não estar estabelecida a relação entre a capacidade funcional e a função ventricular, torna-se necessário identificar se o(s) primeiro(s) sinal(is) de intolerância ao esforço físico está(ão) relacionado(s) a disfunção ventricular. Assim, este trabalho tem como objetivos avaliar em diferentes períodos, 3, 6, 12 e 18 semanas, após indução de estenose aórtica supravalvar em ratos a: 1) função do ventrículo esquerdo em repouso e as alterações morfológicas cardíacas por meio do ecocardiograma; 2) tolerância ao esforço físico, em teste incremental em esteira; 3) relação entre a tolerância ao esforço físico e a função cardíaca determinada em repouso. Foram utilizados 37 ratos Wistar, jovens, machos divididos em dois grupos: controle operado (GC, n=13) e estenose aórtica supravalvar (GEAo, n=24). O GEAo foi submetido a cirurgia com implantação de um clipe na artéria aorta para a indução da estenose aórtica supravalvar. O GC foi submetido à mesma cirurgia, porém sem a implantação do clipe. Os animais foram mantidos com água e ração e ad libitum, em ambiente com temperatura controlada a 23°C e ciclo de luz invertido. Todos os procedimentos foram realizados no ciclo escuro, com o auxílio de iluminação fluorescente vermelha, cuja emissão de onda, por ser longa, não é percebida pelos animais. Dos 24 ratos do grupo estenose aórtica (GEAo), 10 morreram e dois apresentaram sinais de insuficiência cardíaca ao final do experimento, taquipnéia associada a derrame pleural... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Considering that, in studies analyzing the relationship between cardiac remodeling and supravalvar aortic stenosis, the early detection of ventricular dysfunction is important, the hemodynamic method is ideal to detect such dysfunction although it is inadequate for sequential studies, tachypnea is generally manifested when severe cardiac deterioration exists and that the relationship between functional capacity and ventricular function has not been established, it is necessary to identify whether the first sign(s) of exercise intolerance is(are) related to ventricular dysfunction. Hence, this study aimed at evaluating, in different periods - 3, 6, 12 and 18 weeks - after the induction of supravalvar aortic stenosis in rats, the following aspects: 1) function of the left ventricle at rest and cardiac morphological alterations by means of an echocardiogram; 2) exercise tolerance during an incremental test on a treadmill; 3) relationship between exercise tolerance and cardiac function determined at rest. Thirty-seven young male Wistar rats were used. The animals were separated into two groups: operated control (CG, n=13) and supravalvar aortic stenosis (GEAo, n=24). GEAo was submitted to surgery with the implantation of a clip on the aorta artery for induction of supravalvar aortic stenosis. GC was submitted to the same type of surgery although without clip implantation. The animals were given water and chow ad libitum and maintained in a controlledtemperature environment at 23°C and an inverted light-dark cycle. All the procedures were performed in the dark cycle by using red fluorescent illumination, whose long wave emission is not perceived by the animals. Of the 24 rats in the GEAo ten died and two presented signs of cardiac insufficiency at the end of the experiment, tachypnea associated with pleural stroke, thrombus in the left atrium and hypertrophia in the right ventricle, thus... (Complete abstract click electronic access below) / Orientador: Antônio Carlos Cicogna / Coorientador: Katashi Okoshi / Banca: Leonardo Antonio Mamede Zornoff / Banca: Vilmar Baldissera / Mestre

Exercise Tolerance Testing (ETT) is widely accepted as an important diagnostic and prognostic tool and its primary purpose is to assess patients with known or suspected coronary artery disease. Previous studies have focused on concordance between doctors and other supervising personnel in regards to safety outcomes. ETTs are increasingly supervised by nurses now as a result of medical devolvement in this role. This study contributes a new perspective to international literature and focuses on understanding the process of role development for cardiac nurses who supervise ETTs. The overall aim was to gain greater understanding of how cardiac nurses have developed in the role of supervising ETTs and what their process has been. This is a mixed methods study that has utilised both qualitative descriptive techniques and descriptive quantitative data. These data were obtained by individual interviews with ETT nurses and the Clinical Director of Cardiology, and a survey of technicians who work alongside the ETT nurses at a tertiary hospital. Data were also obtained from a national survey of cardiac centres in New Zealand. Both methods were employed to give greater depth to the subject and place local findings in context with national data and international literature. Findings show there have been a number of international and local evolutionary factors contributing to the emergence of the ETT nurse’s role over time. Specific themes emerged from the interviews that describe individual process of role development. Technicians identified that the ETT service has improved as a consequence of having ‘dedicated ETT nurses’. Variability in regards to work place practices, training and assessment were found in the national survey. There is further potential for both increasing the number of nurses practicing as ETT nurses and further expansion of the role, however continued fragmentation, inconsistent service delivery and variation in national standards for practice in New Zealand may be barriers to collective and individual role development.

Dissertation (Ph.D.)--University of Toledo, 2007. / "In partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biomedical Sciences." Title from title page of PDF document. Bibliography: p. 142-183.

Doctor of Philosophy / Department of Kinesiology / David C. Poole / The onset of skeletal muscle contractions induces rapid and robust increases in metabolic rate (V̇O₂) and blood flow (Q̇) in order to supply the energetic demands of the muscle. In young healthy populations, these variables increase proportionally to maintain oxygen flux into the myocyte for both sexes. However, while the resultant changes in V̇O₂ and Q̇ conflate to establish adequate driving pressures of oxygen (PO₂), it appears that the underlying control processes express distinct sexual dimorphism. Estrogen is crucial for cardiovascular control for young women through its relationship with nitric oxide (NO) and results in lower blood pressure and risk of cardiovascular disease for women. However, in post-menopausal women and some disease states, such as heart failure (HF), these protections are lost due to reductions in estrogen and NO bioavailability which causes women to catch and surpass men in rates of hypertension and cardiovascular disease. The purpose of this dissertation is to explore the mechanisms responsible for establishing the oxygen delivery-to-utilization matching (Q̇O₂/V̇O₂) necessary for skeletal muscle contractions in health and disease. In the first investigation (Chapter 1), we explored the effect of altered NO bioavailability on spinotrapezius muscle interstitial space PO₂ (PO₂is; determined by Q̇O₂/V̇O₂) of healthy male and female rats. We show that both sexes regulate PO₂is to similar levels at rest and during skeletal muscle contractions. However, modulating NO bioavailability exposes sex differences in this regulation with females having greater reliance on basal NO bioavailability and males having greater responsiveness to exogenous NO. In the second investigation (Chapter 2), we sought to determine whether measures of central and peripheral function in HF rats predicted exercise tolerance (as critical speed (CS)). We showed for the first time, that CS can be resolved in HF animals and that decrements in central cardiac (echocardiography) and peripheral skeletal muscle function (PO₂is) predicted CS. Building upon these findings, the third investigation (Chapter 3) aimed to determine if the sex differences in the control of PO₂is seen in healthy rats translated to greater deficits in HF for females. Furthermore, this investigation sought to determine if five days of dietary nitrate supplementation (an exogenous NO source) would raise PO₂is in HF rats, with a greater effect seen in females. We revealed that HF reduces PO₂is at rest and during skeletal muscle contractions and this negative effect is exacerbated for females. However, elevating NO bioavailability with dietary nitrate increases resting PO₂is and alters the dynamic response during contractions with females potentially being more responsive than males. The results herein reveal the importance of NO in the control of Q̇O₂/V̇O₂ in health. The onset of HF results in deleterious declines in exercise tolerance, which are mediated through reductions in central and peripheral function, due, in part, to attenuated NO bioavailability. This creates intensified Q̇O₂/V̇O₂ dysfunction in females with HF; however, this can potentially be countered with dietary supplementation of inorganic nitrate. Altogether, the present dissertation suggests that targeting NO bioavailability, particularly in female HF patients, could be a beneficial non-pharmaceutical therapeutic strategy.

Orientador: Fábio de Olivereira Pitta / Banca: Ercy Mara Cipulo Ramos / Banca: Denilson de Castro Teixeira / Resumo: Avaliar as características de atividades físicas na vida diária de pacientes brasileiros portadores de DPOC e sua relação com diferentes variáveis fisiológicas. Métodos: Quarenta pacientes brasileiros portadores de DPOC (18 homens; 66±8 anos; VEF1 46±16%pred; IMC 27±6 Kg.m-2) e 30 idosos saudáveis foram avaliados quanto às atividades físicas na vida diária utilizando-se um acelerômetro multiaxial (Dynaport Activity Monitor, Holanda) por 12 h/dia durante 2 dias da semana. Foram ainda avaliados: capacidade máxima e funcional de exercício (teste incremental máximo e teste de caminhada de 6 minutos [TC6], respectivamente), pressões máximas inspiratória e expiratória (PImax e PEmax, respectivamente), força muscular periférica (1 repetição máxima e força de preensão manual), qualidade de vida (Saint George Respiratory Questionnaire [SGRQ]), estado funcional (questionário London Chest Activity of Daily Living [LCADL]) e sensação de dispnéia (escala do Medical Research Council [MRC]). Resultados: Pacientes portadores de DPOC apresentaram menor tempo gasto andando/dia quando comparados aos idosos saudáveis (55±33 versus 80±28 min/dia; p=0,001) e menor intensidade de movimento (1,9±0,4 versus 2,3±0,6 m/s2; p=0,004). Os pacientes com DPOC também tenderam a passar mais tempo sentados (294±114 versus 246±122 min/dia; p=0,08). O tempo andando/dia correlacionou-se com TC6 (r=0,42; p=0,007), carga máxima de trabalho (r=0,41; p=0,009), idade, MRC e domínio atividade do SGRQ (-0,31≤ r ≤-0,43; p≤0,05 para todos). Conclusão: Apesar de serem mais ativos do que pacientes europeus estudados previamente, pacientes brasileiros portadores de DOPC são menos ativos em comparação a idosos saudáveis. O tempo gasto andando/dia é apenas moderadamente relacionado à capacidade máxima e funcional de exercício / Abstract: To evaluate the characteristics of physical activities in daily life in Brazilian patients with Chronic Obstructive Pulmonary Disease (COPD) and the relationship of these characteristics with different physiologic variables. Methods: Forty Brazilian COPD patients (18 men; 66±8 years; FEV1 46±16%pred; BMI 27±6 Kg.m-2) and 30 healthy age- and sex-matched subjects performed assessment of physical activity in daily life with an accelerometerbased activity monitor (Dynaport Activity Monitor, The Netherlands) for 12 h/day in 2 weekdays. Other measurements included maximal and functional exercise capacity (incremental exercise test and six-minute walk test [6MWT], respectively), maximal inspiratory and expiratory pressures, peripheral muscle force (1-repetition maximum and handgrip force), quality of life (Saint George Respiratory Questionnaire, SGRQ), functional status (London Chest Activity of Daily Living questionnaire) and dyspnea sensation (Medical Research Council scale, MRC). Results: COPD patients had lower daily time spent walking in comparison to healthy elderly (55±33 versus 80±28 min/day; p=0.001) as well as reduced movement intensity (1.9±0.4 versus 2.3±0.6 m/s2; p=0.004). In addition, COPD patients also tended to have more daily sitting time (294±114 versus 246±122 min/day, p=0.08). Time spent walking in daily life was correlated with 6MWT (r=0.42; p=0.007), maximal workload (r=0.41; p=0.009), age, MRC scale and SGRQ activity domain (-0.31 ≤ r ≤ -0.43; all p≤0.05). Conclusion: Despite being more active than previous reports of European COPD cohorts, Brazilian patients with COPD are less active in comparison to healthy elderly. Daily time spent walking in real life is only moderately related with maximal and functional exercise capacity / Mestre

Exercise tolerance, measured as peak oxygen consumption (VO₂ peak), is very low in patients with end-stage renal failure undergoing maintenance haemodialysis. Due to their associated anaemia and low peak heart rates during maximal exercise it has been argued that the reduced blood oxygen carrying capacity and central cardiovascular limitations are primarily responsible for the poor exercise tolerance of these patients. However, others suggest that peripheral (skeletal muscle) limitations including impaired substrate utilization, muscle weakness caused by peripheral neuropathy and myopathy, malnutrition and general physical deconditioning are responsible for the poor exercise tolerance. The present thesis was therefore designed to study whether central cardiovascular function or anaemia or muscle weakness causes patients with end-stage renal failure to terminate exercise at workrates well below those achieved by healthy controls.

Fatigue and exercise intolerance are common symptoms experienced by patients with chronic heart failure (CHF). Historically it has been argued that central cardiopulmonary factors including pulmonary congestion and reduced lung compliance cause dyspnoea that limits the exercise tolerance of such patients. But recent studies have indicated that exercise capacity in patients with CHF may not be limited solely by central cardiorespiratory factors. Rather the focus has shifted to aspects of the peripheral circulation and skeletal muscle function as possible factors limiting the exercise tolerance of patients with CHF. However there are few studies describing both the structural and functional abnormalities in the skeletal muscle of patients with CHF. In the first study of this dissertation, 11 patients with end-stage heart failure (NYHA class Ill-IV) and 10 healthy control subjects (C) underwent i) graded exercise to exhaustion for determination of peak oxygen consumption (VO₂ peak) and peak work load (Wlpeak); ii) isometric and isokinetic tests of skeletal muscle function and iii) radionuclide angiography for determination of ejection fraction (EF%). VO₂ peak (12.5 ± 1.0 vs 34.3 ± 3.5 mlO₂fkg/min; p<0.001), Wlpeak (73 ± 10 vs 224 ± 14 W; p<0.001), total work performed by the quadriceps muscles (TWQ) in a 30 sec isokinetic test (TWQ; 1565 ± 166 vs 2892 ± 345 J; p<0.05), and hamstring muscles (TWH) (TWH; 604 ± 163 vs 2003 ± 326 J; p<0.05), maximum voluntary isometric contraction (MVC) of the quadriceps muscles (MVC; 134 ± 12 vs 194 ± 11 Nm; p<0.001) and isokinetic peak torque of the ~uadriceps (PKTQ) (PKTQ; 133 ± 15 vs 203 ± 23 Nm; p<0.05) and hamstring muscles (PKTH) (PKTH; 60 ± 8 vs 108 ± 16 Nm; p<0.05) and time to fatigue during a test of isometric endurance (68 ± 12 vs 100 ± 10 sec; p<0.05) were all significantly lower in patients with CHF. However when corrected for the reduced lean thigh volume (muscle mass) in patients with CHF, PKTQ, PKTH and MVC were no longer different from control values. But the total work performed by the quadriceps and hamstring muscles in a 30 second isokinetic test was reduced even when corrected for the reduced lean thigh volume in patients with CHF. Furthermore, patients with CHF terminated progressive cycle exercise to exhaustion at heart rates, rates of ventilation, respiratory exchange ratios and blood lactate concentrations that were significantly lower than values achieved by control subjects during maximal dynamic exercise. These data suggest that skeletal muscle functional abnormalities including a decreased resistance to the development of fatigue exist in patients with severe CHF. In the second study of this dissertation, 10 patients with CHF who participated in the first study and eight control subjects underwent a skeletal muscle biopsy of the vastus lateralis muscle for light and electron microscopic analysis. Significant histological and ultrastructural changes were found in all SM biopsies from patients with CHF. These included atrophy and hypertrophy of fibres, fibre splitting, internalized nuclei, nuclear knots, moth-eaten fibres, increased lipid droplets. Electron microscopy showed a large variety of nonspecific abnormalities, including mitochondrial changes, Z-band degeneration and accumulation of intracellular glycogen. Ultrastructural morphometry revealed capillary basement membrane width significantly increased in the SM of patients with CHF, (409 ± 13 vs 121 ± 3 nm; p<0.01). A novel, blinded, impartially scored method for grading SM pathology showed that SM biopsies of patients with CHF had higher scores for myopathic changes compared to C (12.0 ± 1.5 vs 1.6 ± 1.0 arbitrary units; p<0.05). SM pathology score correlated significantly with VO₂ peak, Wlpeak, and TWQ (p<0.05 to p<0.02) but not with EF%. EF% did not correlate with either VO₂ peak, Wlpeak or TWQ. These data support the hypothesis that: i) severe SM structural and functional abnormalities may limit exercise capacity in patients with CHF; ii) the severity of SM pathology but not resting systolic cardiac function, predicts exercise performance in patients with CHF.

No description available.

This diploma thesis takes interest in the issue of physical activities of children with cystic fibrosis, in possible impacts of such activities on clinical condition, in options of prescription of physical activities based on the actual clinical state of a person with cystic fibrosis, and in options of objectification of changes induced by an exercise programme. The theoretic part of this thesis summarizes the current findings about cystic fibrosis, therapy and physical activities in the context of prognosis of patients with cystic fibrosis. In experimental part, we performed examinations on few participants, who were willing to perform a home-based exercise programme. Also, we made a short exploratory questionnaire focused on the attitude of children with cystic fibrosis towards physical exercises. Methodology: We observed the evolution of maximal oxygen uptake VO2max, forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and of the scores of 1- minute sit-to-stand test (1-MSTST). All the measurements were performed before and after 12- weeks long exercise intervention. The inclusion criteria were diagnosis of cystic fibrosis, age over 10 years, FEV1 over 60 % predicted and no present signs of an acute exacerbation. Participants were assessed by spirometry examination,...