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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

EFEITO DO TREINAMENTO AERÓBIO NOS PARÂMETROS CARDIOVASCULARES DE PACIENTES EM HEMODIÁLISE / EFFECT OF AEROBIC TRAINING IN PARAMETERS CARDIOVASCULAR PATIENTS IN HEMODIALYSIS

AZOUBEL, Luana Manaisse 05 May 2017 (has links)
Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-07-18T13:47:20Z No. of bitstreams: 1 Luana Azoubel.pdf: 13315246 bytes, checksum: f1f9522c4da46dc3eae1e7295ce5f6e8 (MD5) / Made available in DSpace on 2017-07-18T13:47:45Z (GMT). No. of bitstreams: 1 Luana Azoubel.pdf: 13315246 bytes, checksum: f1f9522c4da46dc3eae1e7295ce5f6e8 (MD5) Previous issue date: 2017-05-05 / CNPQ / Introduction: Chronic kidney disease is an epidemical problem raising all over the world, it is estimated that one million individuals undergo dialysis treatment and in Brazil this number is around 112.000. Several studies have been shown the high prevalence of autonomic disfunction in hemodialysis patients and this disfunction is associated to cardiac events such sudden cardiac death, heart failure and myocardial infarction. In contrast, aerobic training is an important ally in autonomic improvement and hence in heart rate variability. Objective: Verify cardiovascular adaptations 12 weeks post aerobic training in hemodialysis patients. Materials and methods: 14 patients undergoing hemodialysis treatment joined the study, they were divided in two groups, a control group (GC) and active group (GA), both with 7 subjects (4 women). This study occurred at Centro de Prevenção de Doenças Renais at Hospital Universitário Presidente Dutra of Universidade Federal do Maranhão and Centro de Nefrologia do Maranhão. The subjects of GA underwent an aerobic exercise protocol, an intensity between 60% and 80% of maximal heart rate. The data normality was analyzed by Shapiro-Wilk test, for groups characterization we adopted Student’s paired T test and Wilcoxon for non parametrics values. Statistical analysis between groups was tested with two-way ANOVA and post-hoc Student Newman-Keulls. Results: Body composition between groups was different for both body mass index from 24,71±2,34 to 18,88±1,83 and fat mass 22,70±4,94 to 13,69±3,05 in GA. Cardiovascular parameters in GA, resting heart rate was lower in post training 77,14±9,08 to 69,86±7,53 and VO2 values rised significantly from 18,98±0,82 to 22,53±2,63 in comparision between baseline and after 12 weeks the values. Systolic blood pressure was lower at sleep period, with 120,80±10,85 (mmHg) in baseline and 109,00±15,00 (mmHg) post training at Day 1 and also in Day 2, with 127,20±15,82 mmHg in baseline and 110,70±16,40 mmHg post training. In Day 2, after aerobic protocol intervention there was a reduction in systolic blood pressure value from waking period to sleep period, with 125,50±17,03 mmHg and 110,70±16,40 mmHg respectively. In regard to GA autonomic modulation, HF (n.u) index improved from 47,41±15,95 (n.u) to 69,35±19,3 (n.u) and sympathovagal balance decreased from 1,20±0,60 to 0,59±0,68, when compared their baselines and after 12 weeks values. Between groups, GA showed better values, HF (n.u) index and LF/HF respectively were 69,35±19,37 (n.u); 0,59±0,63 and 43,63±21,07 (n.u); 2,40±3,13 and GC the values were 43,63±21,07 (n.u); and 2,40±3,13. Conclusion: Moderate aerobic training, in 12 weeks, improved cardiorespiratory fitness and autonomic modulation in hemodialysis patients. Besides, GA at the end of this study had better body composition values then GC. / Introdução: A Doença Renal Crônica (DRC) é um crescente problema epidemiológico, estimase que no mundo mais de 1 milhão de pessoas realize tratamento dialítico, e no Brasil este número aparece em torno de 112 mil indivíduos aproximadamente. Estudos têm demonstrado alta prevalência de disfunção autonômica em pacientes submetidos à hemodiálise, e esta disfunção está associada à eventos cardíacos como morte súbita, insuficiência cardíaca e infarto do miocárdio. O treinamento aeróbio é um importante aliado na melhora do balanço autonômico e consequentemente na variabilidade da frequência cardíaca (VFC). Objetivo: Avaliar as alterações cardiovasculares de pacientes em hemodiálise após 12 semanas de treinamento aeróbio. Materiais e métodos: 14 pacientes submetidos ao tratamento dialítico participaram deste estudo, estes foram alocados em dois grupos, ativos (GA) e controle (GC) com 7 indivíduos (4 mulheres e 3 homens) cada. Este estudo foi realizado no Centro de Prevenção de Doenças Renais (CPDR), do Hospital Universitário Presidente Dutra (HUPD), da Universidade Federal do Maranhão (UFMA) e Centro de Nefrologia do Maranhão (CENEFROM). Os participantes do GA foram submetidos a um protocolo de treinamento aeróbio com intensidade de 60% a 80% da frequência cardíaca máxima. Os dados tiveram sua normalidade testada através do teste de Shapiro-Wilk, e para caracterização entre grupos adotamos o teste T pareado de Student e Wilcoxon para variáveis não pareadas. A análise estatítica entre os grupos foi realizada através do teste two-way ANOVA com post-hoc Student Newman-Keulls. Resultados: A composição corporal entre os grupos foi diferente para o índice da massa corpórea de 24,71±2,34 kg/m² para 18,88±1,83 kg/m² e massa gorda de 22,70±4,94 kg para 13,69±3,05 kg, o GA apresentou valores melhores em relação ao GC. Na análise dos parâmetros cardiovasculares, no GA a FC de repouso reduziu de 77,14±9,08 bpm para 69,86±7,53 bpm e o VO2 pico aumentou significativamente em relação aos seus níveis basais de 18,98±0,82 ml.kg.min para 22,53±2,63 ml.kg.min, o valor do VO2 após 12 semanas de intervenção foi maior no GA, com valor de 22,53±2,63 ml.kg.min para 18,23±0,82 ml.kg.min do GC. A PAS no período do sono, teve seus valores diminuídos ao compararmos basal e pós tanto no Dia-1 de 120,80±10,85 mmHg para 109,00±15,00 mmHg, como no Dia-2 de 127,20±15,82 mmHg para 110,70±16,40 mmHg. No Dia-2 após a intervenção com protocolo aeróbio houve redução do valor da PAS do período de vigília para o período do sono, de 125,50±17,03 mmHg para 110,70±16,40 mmHg, respectivamente. Os valores ecocardiográficos não obtiveram diferenças significativas. No que concerne à modulação autonômica do GA, este alcançou melhora no índice HF (n.u) de 47,41±15,95 (n.u) para 69,35±19,37 (n.u) e no balanço simpatovagal com redução de 1,20±0,60 para 0,59±0,68, comparando seus valores basais e pós 12 semanas. Entre grupos, o GA obteve melhores valores de VFC, o índice HF (n.u) e o LF/HF do GA foram respectivamente 69,35±19,37 (n.u); 0,59±0,63 e para o GC os valores foram 43,63±21,07 (n.u); 2,40±3,13. Conclusão: O treinamento aeróbio de intensidade moderada, em 12 semanas, proporcionou melhora cardiorrespiratória e autonômica nos pacientes submetidos à hemodiálise. Além disso, o GA obteve valores de composição corpórea melhores que os sedentários ao final do estudo.
232

EFEITO DO FORTALECIMENTO MUSCULAR INSPIRATÓRIO NA FORÇA MUSCULAR RESPIRATÓRIA, VARIABILIDADE DA FREQUÊNCIA CARDÍACA, PRESSÃO ARTERIAL E QUALIDADE DE VIDA DE MULHERES EM HEMODIÁLISE. / EFFECT OF INSPIRATIONAL MUSCULAR STRENGTH IN RESPIRATORY MUSCLE FORCE, VARIABILITY OF HEART RATE, BLOOD PRESSURE, AND QUALITY OF LIFE OF WOMEN IN HEMODIALYSIS.

DIAS, Aíla Maria Castro 07 July 2017 (has links)
Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-11-27T17:07:13Z No. of bitstreams: 1 Aíla.pdf: 9853381 bytes, checksum: 2f057088f4fd20c386228011f9af7aa4 (MD5) / Made available in DSpace on 2017-11-27T17:07:13Z (GMT). No. of bitstreams: 1 Aíla.pdf: 9853381 bytes, checksum: 2f057088f4fd20c386228011f9af7aa4 (MD5) Previous issue date: 2017-07-07 / CAPES. / Introduction: Chronic Kidney Disease (CKD) is a gradual onset disease in which the individual becomes subject to dialysis, defined by structural abnormalities of the kidneys that can lead to a reduction in renal function, diagnosed by a glomerular filtration of less than 60 ml/min /1.73 m2 for a period of three months or more. Hemodialysis (HD) is the most used treatment, being responsible for extracorporeal blood filtration. In the muscular system, the most affected by muscular atrophy would be the respiratory system. Cardiovascular diseases are the main cause of morbidity and mortality in this population. More than 50% of all deaths occurring in renal patients are due to cardiovascular events. With the dysfunctional autonomic nervous system (ANS), there is a reduction in heart rate variability (HRV) and the development of complex arrhythmias. The multiple limitations and complications of CKD have a negative impact on the quality of life of these patients.Objective: Investigating whether inspiratory muscle training (IMT) in chronic renal patients on hemodialysis can provide additional benefits to the cardiopulmonary system, the autonomic nervous system, and quality of life. Methods: Thirteen women in Hemodialysis Treatment were selected for an inspiratory muscle training program (IMT) with Threshold IMT at 40% of Maximum Inspiratory Pressure (MIP) for 30 daily minutes, during 7 days, for 12 weeks. The maximal MIP and Expiratory Pressure (MEP), blood pressure (BP) before and after each training, Heart Rate Variability (HRV) analysis, pulmonary functional capacity were assessed by the 6-minute walk test (6MWT) and the quality of life by KDQOLSFTM. Results: MIP increased -35.33 ± 20.49 cmH20 to -58.89 ± 23.02 cmH20 (p <0.0028), from MEP 51.67 ± 30 cmH20 to 65.56 ± 20.07 cmH20 (p <0.0281). In the HRV there was no statistically significant improvement. Quality of life improved on Symptoms/ Problems scores at weeks 4, 8 and 12 compared to week 0 (p <0.0009), and on Cognitive Function with improvement at week 12 compared to week 0 (p <0.0491) . The creatinine values presented a statistically significant decrease in the values of weeks 4, 8 and 12 compared to week 0, with p = 0.0004. Conclusion: IMT proved to be an easily applicable alternative treatment for improving respiratory muscle strength and serum creatinine levels, and may be widely used in patients with CKD, concomitant with hemodialysis treatment. / Introdução: A Doença Renal Crônica (DRC) é uma doença de início gradativo, na qual o indivíduo se torna sujeito ao tratamento dialítico, definido por anormalidades estruturais dos rins que podem levar à redução da função renal, diagnosticada por uma filtração glomerular menor que 60 ml/min/1,73 m2 durante um período de três meses ou mais. A hemodiálise (HD) é o tratamento para a DRC mais utilizada, sendo responsável pela filtração extracorpórea do sangue. No sistema muscular, o mais afetado por atrofia muscular, é o sistema respiratório. As doenças cardiovasculares são a principal causa de morbidade e mortalidade nessa população. Mais de 50% do total de mortes que ocorrem nos doentes renais são por eventos cardiovasculares. Com o sistema nervoso autônomo (SNA) disfuncional, há uma redução na variabilidade da frequência cardíaca (VFC) e o desenvolvimento de arritmias complexas. As limitações e complicações múltiplas da DRC têm um impacto negativo na qualidade de vida desses pacientes. Objetivo: Investigar se o treinamento muscular inspiratório (TMI) nos pacientes renais crônicos em hemodiálise pode proporcionar benefícios adicionais ao sistema cardiopulmonar, ao sistema nervoso autônomo e na qualidade de vida. Metodologia: Foram selecionadas 13 mulheres em Tratamento Hemodialítico, para um programa de treinamento da musculatura inspiratória (TMI), com Threshold IMT, a 40% da Pressão Inspiratória Máxima (PImax) por 30 minutos diários, 7 dias, por 12 semanas. Foram avaliadas a PImáx e Pressão Expiratória máxima (PEmáx), pressão arterial (PA) antes e após cada treino, análise da Variabilidade da Frequência Cardíaca (VFC), capacidade funcional pulmonar pelo Teste de caminhada de 6 minutos (TC6) e da qualidade de vida pelo KDQOL-SFTM. Resultados: Foi encontrado aumento da PImáx -35,33±20,49 cmH20 para -58,89± 23,02cmH20 (p<0,0028), da PEmáx 51,67±30cmH20 para 65,56± 20,07cmH20 (p<0,0281). Na VFC não houve melhora estatisticamente significativa. A qualidade de vida apresentou melhoras nos escores Sintomas/Problemas nas semanas 4,8 e 12 comparado à semana 0 (p<0,0009), e na Função Cognitiva com melhora na semana 12 comparada à semana 0 (p<0,0491). Os valores de creatinina apresentaram diminuição estatisticamente significativa nos valores das semanas 4, 8 e 12 comparados a semana 0, com p = 0,0004. Conclusão: O TMI mostrou ser uma alternativa de tratamento de fácil aplicação para melhora da força muscular respiratória e nos valores de creatinina sérica, podendo ser amplamente utilizado em pacientes com DRC, concomitante ao tratamento hemodialítico.
233

Interação entre limiar de dor e função autonômica após restrição de sono em indivíduos saudáveis

Dall'Agnol, Letizzia January 2011 (has links)
Introdução: Embora a relação entre privação de sono e limiar de dor tenha sido estudada em condições patológicas de quadros álgicos agudos e crônicos, os mecanismos envolvidos neste processo ainda carecem de investigações. Nesse contexto, sabe-se que são crescentes as situações nas quais a restrição de sono aguda é induzida por atividades laborais cotidianas, e a compreensão desta relação demanda modelos que permitam observar o efeito em condições em que os estímulos sejam padronizados e controlados. Assim sendo, investigamos o efeito da restrição aguda de sono na função autonômica e sua relação com limiares de dor em indivíduos saudáveis. Objetivos: Avaliar a relação entre respostas autonômicas e percepção a estímulos nociceptivos térmicos e elétricos pós-restrição aguda de sono ocasionada por estresse laboral. Métodos: Foram avaliados 19 estudantes de Medicina saudáveis após noite de sono habitual (SN) e após plantão noturno de 12 horas (RS). Primeiramente examinamos características clínicas dos sujeitos utilizando escalas para avaliação de sono e sintomas psiquiátricos. Foram realizados também testes quantitativos de sensibilidade para sensações térmicas e elétricas e registradas respostas cutâneas simpáticas (RCS) induzidas por estímulo elétrico duplo com diferentes intervalos interestímulos (ISI). Resultados: A média de duração do sono durante as 12 horas de plantão noturno foi de 120+ 28 minutos. Os escores de ansiedade foram maiores na fase RS quando comparados com os da fase SN (p<0,01). Após restrição de sono, houve diminuição no limiar de dor, mas não nos limiares de calor e elétricos. Em relação às respostas autonômicas, foram evidenciadas maiores amplitudes da RCS bem como aumento do número de duplas respostas em ISI 2s na fase RS. Também foi observada moderada correlação inversa entre limiares de dor e amplitudes da RCS (r= -0,45; p<0,01). Não foi encontrada correlação entre escores de ansiedade e parâmetros RCS. No entanto, no modelo de regressão linear multivariada, a percepção do limiar de dor ao estímulo térmico foi significativamente correlacionada com a amplitude da resposta cutânea simpática (β = - 0.55; 95% CI, -0.65 to -0.07), mas não com escores de ansiedade (p>0.05). Conclusões: Os efeitos da restrição aguda de sono no limar de dor são específicos e parecem não estar relacionados com alterações na percepção sensorial geral. Hiperalgesia foi associada com respostas autonômicas anormais, mas não com aumento da ansiedade, sugerindo a existência de uma associação entre o sistema nociceptivo e o autonômico, independente do estado emocional. / Background: Although the relationship between sleep deprivation and pain threshold has been studied in pathological acute and chronic conditions, the mechanisms involved in this process still require investigation. In this context, it is known that there is an increasing of situations where acute sleep restriction is induced by daily working activities and to understand this relationship is necessary models that allow the observation of the effect in situations in which the stimuli are standardized and controlled. Therefore, we investigated the effect of the acute sleep restriction on autonomic function and its relation with pain thresholds in healthy subjects. Objectives: Evaluating the relationship between autonomic responses and perception of thermal and electrical nociceptive stimuli after acute sleep restriction caused by stressful work. Methods: We evaluated 19 healthy medical students after normal night of sleep (NS) and after 12-hour night shift (SR). First we examined clinical characteristics of the subjects using scales for assessment of sleep and psychiatric symptoms. Also, we performed quantitative tests of sensitivity to thermal and electrical sensations and recorded double-electric-induced sudomotor skin responses (SSR) at different inter-stimulus intervals (ISI). Results: The total mean duration of sleep was 120 ± 28 minutes out of 12 hours of night shift. The anxiety scores were higher in SR Phase in comparison with those from NS Phase (p<0.01). After SR, there was a decrease in heat pain, but not in warm neither electrical threshold. Regarding autonomic responses, SR subjects showed higher SSR amplitudes and increased number of double responses at ISI 2s. It was also observed a moderate inverse correlation between heat pain thresholds and SSR amplitude (r = -0.45; P<0.01). However, there was no correlation between anxiety scores and SSR parameters. Indeed, in the multivariate linear regression model, heat pain perception was significantly correlated with SSR amplitudes (β = - 0.55; 95% CI, -0.65 to -0.07), but not with anxiety scores (p>0.05). Conclusions: The effects of SR on pain are specific and seem to be not related to general changes in sensory perception. Hyperalgesia was associated with abnormal autonomic responses, but not with increased anxiety, suggesting an association between the nociceptive and autonomic systems, independent of the emotional state.
234

Modulação do sistema nervoso autônomo mensurado pela análise da variabilidade da freqüência cardíaca em pacientes com fibromialgia / Modulation of autonomic nervous system measured by heart rate variability in patients with fibromyalgia

Necchi, Lúcia Helena de Góes 14 February 2007 (has links)
INTRODUÇÃO: Pacientes com fibromialgia (FM) apresentam distúrbios no sistema de resposta ao estresse, o qual é composto pelo eixo hipotalâmico-pituitário-adrenal (HPA) e pelo sistema nervoso autônomo. Recentemente, tem havido muito interesse na possível função do sistema nervoso autônomo na patogênese da FM. O objetivo deste estudo foi avaliar a interação entre os sistemas simpático e parassimpático, em mulheres com FM e mulheres saudáveis, utilizando a análise da variabilidade da freqüência cardíaca (VFC). MÉTODOS: Foram estudadas 20 mulheres com FM com idades entre 35 e 55 anos, e 20 controles saudáveis pareados pela idade, gênero e índice de massa corporal. A VFC foi analisada sobre gravações eletrocardiográficas, obtidas através da monitorização eletrocardiográfica ambulatorial (Holter) de 24 horas, e avaliada pelos índices da VFC no domínio do tempo (SDNN, SDANN, SDNNi, RMSSD e pNN50) e no domínio da freqüência (LF, HF, WF e LF/HF). A VFC foi analisada durante o período de 24 horas e também durante o período noturno, entre 01:00 e 04:00 h AM, consideradas como horas de sono. O equilíbrio simpato-vagal foi analisado através da razão LF/HF, sendo as faixas de freqüências da LF (0,04-0,15 Hz) considerada como predominantemente simpática, e da HF (0,15-0,50 Hz) considerada como predominantemente parassimpática. RESULTADOS: Não houve diferença de idade entre pacientes com FM e o grupo controle (44,40 ± 5,01 e 44,65 ± 5,32 anos, respectivamente; p=0,879). Os índices que refletem o sistema nervoso parassimpático, mostraram um comportamento similar entre pacientes com FM, mas revelaram atividade significativamente diminuída quando comparado ao grupo controle, ambos durante o período noturno e durante o período de 24 horas (p<0,05). Não houveram diferenças entre os índices que refletem o sistema simpático entre os grupo FM e controle (p>0,05), assim como não mostraram hiperatividade simpática. Contudo, a razão LF/HF foi significativamente maior em pacientes com FM, quando comparado ao grupo controle, ambos durante o período de sono (p=0,015) como durante o período de 24 horas (p=0,025), sugerindo predominância simpática em indivíduos com FM. CONCLUSÃO: Nossos resultados sugerem que pacientes com FM apresentam predominância da atividade simpática, associado ao tônus parassimpático diminuído. Sob condições basais não foi detectada hiperatividade simpática, uma vez que a atividade simpática não mostrou alterações significantes. / INTRODUCTION: Patients with fibromyalgia (FM) exhibit disturbances of the stress-response system, which is composed by hypothalamic-pituitary-adrenal axis (HPA) and autonomic nervous system. Recently, much interest has been expressed in the possible role of the autonomic nervous system in the pathogenesis of FM. The aim of this study was to assess the interation between sympathetic and parasympathetic systems, in FM and health women, using heart hate variability (HRV) analysis. METHODS: It was studied 20 women with FM aged between 35 and 55 years-old, and 20 healthy controls matched for age, sex and body mass index. HRV was assessed over electrocardiographic recordings, obtained by 24-hours ambulatory electrocardiography monitoring (Holter), and evaluated by time domain indexes (SDNN, SDANN, SDNNi, RMSSD e pNN50) and frequency domain indexes (LF, HF, WF e LF/HF). HRV was analyzed over the 24-hours period and also over the night period, between 01:00 and 04:00 AM, considered as sleep hours. Sympathovagal balance was analysed by LF/HF ratio, with LF band (0.04-0.15 Hz) considered as sympathetic predominance, and HF band (0.15-0.50 Hz) considered as parasympathetic predominance. RESULTS: There was no age difference between FM patients and control group (44.40 ± 5.01 and 44.65 ± 5.32 years, respectively; p=0.879). The indexes that reflect parasympathetic nervous system, showed a similar behavior among FM patients, but revealed a significantly decreased activity when compared to control group, both during the nocturnal period as well during the 24h period (p<0.05). There was no difference between the indexes that reflect sympathetic system in FM patients and controls (p>0.05), as did not show sympathetic hyperactivity. However, the ratio LH/HF was significantly higher in FM patients, when compared to control group, both during the sleep period (p=0.015) as well as over the 24h period (p=0.025), suggesting a sympathetic predominance in FM subjects. CONCLUSION: Our data suggest that FM patients present a predominance of sympathetic activity, associated with a reduced parasympathetic tonus. Under basal conditions sympathetic hyperactivity was not detected, since sympathetic activity did not show significant alterations.
235

Estudo dos efeitos da Síndrome dos Ovários Policísticos sobre o controle autonômico cardiovascular, com enfoque na sensibilidade barorreflexa e na variabilidade da frequência cardíaca e da pressão arterial - análises pelos métodos linear e não-linear / Study of the effects of Polycystic Ovarian Syndrome on cardiovascular autonomic control, focusing on baroreflex sensitivity and on the variability of heart rate and blood pressure - analysis by linear and nonlinear methods

Philbois, Stella Vieira 29 September 2017 (has links)
A Síndrome dos Ovários Policísticos (SOP) afeta uma grande parcela da população feminina em idade reprodutiva. Além das alterações morfológicas, hormonais e metabólicas, essas mulheres também apresentam uma alta prevalência de obesidade e alterações no controle autonômico cardiovascular de acordo com a literatura, principalmente modificações na modulação autonômica da variabilidade da frequência cardíaca (VFC). No entanto, pouco sabemos sobre outros parâmetros do controle autonômico, como a variabilidade da pressão arterial (VPA) e a sensibilidade barorreflexa (SBR). Portanto, o principal objetivo do estudo foi investigar em mulheres com a SOP as alterações na modulação autonômica da VPA e na SBR, bem como avaliar se essas alterações são decorrentes da SOP ou do aumento da gordura corporal. Para tanto, foram estudadas 30 mulheres voluntárias eutróficas (IMC ? 25 kg/m2) sem a SOP e 60 mulheres voluntárias com a SOP divididas em dois grupos: eutróficas (IMC ? 25 kg/m2; N=30) e obesas (IMC ? 30 kg/m2; N=30). Todas as mulheres foram submetidas aos seguintes protocolos; coleta de sangue para hemograma completo; avaliação antropométrica e avaliação de parâmetros metabólicos e hormonais em repouso; registro de parâmetros hemodinâmicos e cardiorrespiratórios em repouso e durante o exercício físico; análise da VFC e da VPA; e análise da SBR espontânea. A comparação entre os grupos eutróficos com e sem SOP não apresentou qualquer diferença nos parâmetros autonômicos avaliados. No entanto, a comparação entre os grupos SOP mostrou que o grupo SOP obeso apresentou menores valores de VO2 e testosterona, e maiores valores de triglicerídeos e da pressão arterial em relação ao grupo SOP eutrófico. Quanto aos parâmetros autonômicos, os grupos obeso e eutrófico não diferiram na análise da VPA. Entretanto, o grupo SOP obeso apresentou menores valores da SBR espontânea e das oscilações de baixa frequência (LF) da VFC em unidades absolutas. Por fim, nossos resultados sugerem que a obesidade pouco alterou a VFC em mulheres com SOP, entretanto reduziu sensivelmente a SBR espontânea. Esses achados podem estar associados com diferenças hormonais encontradas nessas mulheres, como os níveis séricos de testosterona mais elevados no grupo eutrófico. / Polycystic Ovarian Syndrome (PCOS) affects a large proportion of the female population at reproductive age. In addition to morphological, hormonal and metabolic alterations, these women also present a high prevalence of obesity and alterations in cardiovascular autonomic control according to the literature. Mainly modifications in the autonomic modulation of heart rate variability (HRV). However, we do not know much about other parameters of autonomic control, such as blood pressure variability (APV) and baroreflex sensitivity (SBR). Therefore, the main objective of the study was to investigate in women with PCOS changes in the autonomic modulation of APV and SBR, as well as to assess whether these alterations are due to PCOS or increased body fat. In order to do, 30 eutrophic non-PCOS voluntary women (BMI ? 25 kg / m2) and 60 voluntary PCOS women who were studied in two groups: PCOS eutrophic (BMI ? 25 kg / m2, N = 30) and PCOS obese women (BMI ? 30 kg / m2, N = 30). All the women were submitted to the following protocols; collection of blood for complete blood count; anthropometric evaluation and evaluation of metabolic and hormonal parameters at rest; recording of hemodynamic and cardiorespiratory parameters at rest and during physical exercise; analysis of HRV, APV and spontaneous SBR analysis. The comparison between the eutrophic PCOS and nonPCOS groups showed no difference in the autonomic parameters evaluated. However, the comparison between the PCOS groups showed that the PCOS obese group presented lower values of VO2 and testosterone, and higher triglyceride values and blood pressure in relation to the PCOS eutrophic group. Regarding the autonomic parameters, the PCOS obese and eutrophic groups did not differ in the APV analysis. However, the PCOS obese group presented lower values of spontaneous SBR and low frequency oscillations (LF) of HRV in absolute units. Finally, our results suggest that obesity did not significantly alter HRV in women with PCOS, but it significantly reduced spontaneous SBR. These findings may be associated with hormonal differences found in these women, such as higher serum testosterone levels in the PCOS eutrophic group.
236

On the development of the parasympathetic, enteric and sacral nervous systems / Sur le développement des systèmes nerveux parasympathique, entérique et sacré

Espinosa Medina, Isabel 03 March 2017 (has links)
Les cellules de la crête neurale migrent extensivement et forment le système nerveux autonome comprenant les ganglions parasympathiques, sympathiques et entériques, qui maintiennent l'homéostasie. Dans cette étude, j'explore les migrations, interactions neuronales et dépendances moléculaires lors de la formation des circuits nerveux autonomes. Je démontre que les précurseurs des ganglions parasympathiques dérivent des précurseurs des cellules de Schwann (SCPs) qui envahissent les nerfs préganglionaires jusqu'à leur destination, proche des organes cibles (Espinosa-Medina et al., 2014). D'autre part, je montre un parallélisme entre le mécanisme de migration des précurseurs parasympathiques et celui d'une population de précurseurs du système nerveux ¿sophagien, qui migrent le long le nerve vague. Enfin, je propose un réexamen du système nerveux sacré, qui régule les fonctions urinaire, digestive et reproductrice et qui est considéré comme parasympathique depuis plus d'un siècle, sans argument moléculaire. Je présente une signature moléculaire pour distinguer les neurones parasympathiques crâniens et les neurones sympathiques thoraco-lombaires et démontre que le système nerveux sacré est en fait sympathique. En conséquence, le système nerveux autonome est composé de trois divisions contrastées par leur origine embryonnaire aussi que leur anatomie adulte: une parasympathique d'origine et de connectivité exclusivement crânienne, une sympathique spinale, allant de l'étage cervical au sacré (Espinosa-Medina et al., 2016) et une division entérique que son origine aussi bien que sa connectivité placent à l'interface des systèmes sympathique et parasympathique. / Neural crest cells migrate extensively to form the autonomic nervous system including sympathetic, parasympathetic and enteric ganglia essential for regulating bodily homeostasis. In the present work, I explore the migratory mechanisms and neuronal interactions during autonomic circuit assembly, as well as their molecular dependencies. I show that parasympathetic ganglia derive from Schwann cell precursors (SCPs) and migrate along their preganglionic nerves to locate close to their target tissues (Espinosa-Medina et al., 2014). In line with this work, I show that vagal-associated SCPs give rise to part of the oesophageal nervous system, whereas cervical sympathetic-like crest cells colonize all the gastrointestinal tract, demonstrating a dual origin and different migration mechanisms for enteric neurons. Finally, I revise the identity of the sacral autonomic outflow, whose allocation to the parasympathetic nervous system has been accepted for a century. Sacral autonomic neurons control rectal, bladder, and genital functions and analysis of their cellular phenotype was lacking. Here I present a differential molecular signature for cranial parasympathetic versus thoraco-lumbar sympathetic neurons and show that, in this light, the sacral autonomic outflow is sympathetic. Accordingly, the parasympathetic nervous system receives input from cranial nerves exclusively and the sympathetic nervous system from spinal nerves, thoracic to sacral inclusively (Espinosa-Medina et al., 2016). Interestingly the enteric nervous system, which receives input from both sympathetic and parasympathetic nerves, shares with each system aspects of its ontogeny.
237

TARGETING MALADAPTIVE PLASTICITY AFTER SPINAL CORD INJURY TO PREVENT THE DEVELOPMENT OF AUTONOMIC DYSREFLEXIA

Eldahan, Khalid C. 01 January 2019 (has links)
Vital autonomic and cardiovascular functions are susceptible to dysfunction after spinal cord injury (SCI), with cardiovascular dysregulation contributing to morbidity and mortality in the SCI population. Autonomic dysreflexia (AD) is a condition that develops after injury to the sixth thoracic spinal segment or higher and is characterized by potentially dangerous and volatile surges in arterial pressure often accompanied with irregular heart rate, headache, sweating, flushing of the skin, and nasal congestion. These symptoms occur in response to abnormal outflow of sympathetic activity from the decentralized spinal cord typically triggered by noxious, yet unperceived nociceptive stimulation beneath the level of lesion. Maladaptive plasticity of primary afferents and spinal interneurons influencing sympathetic preganglionic neurons is known to contribute to the development of AD. However, there are currently no treatments capable of targeting this underlying pathophysiology. The goal of this work was to test pharmacological agents for their potential to modify intraspinal plasticity associated with AD in order to prophylactically prevent the development of this condition altogether. We first tested whether the drug rapamycin (RAP), a well-studied inhibitor of the growth promoting kinase “mammalian target of rapamycin” (mTOR), could prevent aberrant sprouting of primary c-fiber afferents in association with reduced indices of AD severity. Naïve and T4-transected rats undergoing 24/7 cardiovascular monitoring were treated with rapamycin (i.p.) for 4 weeks before tissue collection. RAP attenuated intraspinal mTOR activity after injury, however it also caused toxic weight loss. RAP treated SCI rats developed abnormally high blood pressure both at rest and during colorectal distension (CRD) induced AD, as well as more frequent bouts of spontaneous AD (sAD). These cardiovascular alterations occurred without altered intraspinal c-fiber sprouting. Our finding that rapamycin exacerbates cardiovascular dysfunction after SCI underscores the importance of screening potential pharmacological agents for cardiovascular side effects and suggests that the mTOR pathway plays a limited or dispensable role in c-fiber sprouting after SCI. We next examined the effects of the antinociceptive drug gabapentin (GBP) on AD development. Our previous work demonstrated that a single acute administration of GBP can reduce the severity of AD. The mechanism of action, however, remains unclear. Emerging evidence suggests that GBP may act by blocking de novo synaptogenesis. We investigated whether continuous GBP treatment could attenuate the development of AD by modifying synaptic connectivity between primary afferents and ascending propriospinal neurons. SCI rats were treated with GBP every six hours for four weeks. We found that GBP reduced blood pressure during CRD stimulation and prevented bradycardia typically observed during AD. However, GBP treated rats also had a higher sAD frequency and failed to return to pre-injury body weight. Moreover, SCI reduced the density of putative excitatory (VGLUT2+) and inhibitory (VGAT+) synaptic puncta in the lumbosacral cord, although GBP did not alter these parameters. Our results suggest that continuous GBP treatment alters hemodynamic control after SCI and that decreased synaptic connectivity may contribute to the development of AD. These studies demonstrate the need for further research to better understand the cellular signaling driving maladaptive plasticity after SCI as well as the complex and dynamic changes in intraspinal synaptic connectivity contributing to the development of AD. Moreover, GBP treatment may offer clinical benefit by reducing blood pressure during AD, however the optimal dosage must be identified to avoid undesired side-effects.
238

HEART RATE DYNAMICS DURING AND AFTER SIMULATED FIRE GROUND TASKS: EFFECTS OF PHYSICAL FITNESS AND TRAINING

Saari, Anssi Ilmari 01 January 2019 (has links)
Firefighting is a strenuous occupation that increases the risk of cardiovascular events. Greater levels of physical fitness and training improve firefighters’ occupational performance, but little is known whether they are related to lower physiological stress and recovery from fire ground tasks. Heart rate, heart rate recovery and heart rate variability have been used to evaluate physical stress in association with exercise and fire ground tasks. However, there is a paucity of research evaluating the effects of physical fitness and training on heart rate dynamics during a simulated fire ground test (SFGT). Therefore, the primary purposes of this study were to evaluate the relationships between heart rate dynamics during a SFGT and to determine the effects of physical characteristics, fitness and physical training on these measures. The secondary purpose was to assess the relationship between maximal pace SFGT time and heart rate responses from a standardized pace SFGT. This information will help to understand the relationship between occupational performance and level of physical stress associated with work on the fire ground. Twenty-one firefighter academy recruits (Age = 28.4 ± 4.0 yr; Height = 177.1 ± 6.9 cm; Body mass = 88.3 ± 15.4 kg) participated in this cross-sectional and longitudinal study. The subjects completed a battery of physical fitness tests, including a 1.5-mile run, maximal pull-ups, push-ups, sit-ups, and isometric plank hold. In addition, the subjects completed a standardized pace SFGT that consisted of typical fire ground tasks performed in succession, without recovery (i.e., high-rise pack carry, hose drag, equipment carry, ladder raise, forcible entry, search, and victim rescue tasks). Heart rate variability was measured pre- and post-SFGT, and heart rate and 60 s heart rate recovery were measured during and post-SFGT, respectively. After a 10 wk physical training intervention, composed of approximately four physical training sessions per week, the measurements were repeated. A subsample of the original cohort (n = 11) also completed a maximal pace SFGT where their completion time was used as a measure of work capacity. Independent variables for this study included the physical and fitness test measures, physical training and maximal pace SFGT completion time. Dependent variables for this study were mean heart rate reserve during the SFGT (HRRes), difference between resting and mean heart rate during SFGT (HRSFGT-Rest), 60-second heart rate recovery (HRR60), and the difference between resting and post-SFGT root mean square of standard deviation between consecutive heart beats in logarithmic scale (LnRMSSDPost-Rest) measured with standardized pace SFGT. Independent and dependent variables were obtained at baseline and after physical training. Pearson r correlation coefficient was used to evaluate associations between outcome measures. Dependent samples t-test was used to compare differences in outcome measures at baseline and following physical training. Linear regression was used to evaluate the association between independent and dependent variables with standardized pace SFGT at baseline. Linear regression was used to assess the relationship between maximal pace SFGT time and outcome measures during the standardized pace SFGT. The level of significance was set as p ≤ 0.05 for all statistical analyses. In the standardized pace SFGT there was a positive correlation between HRSFGT-Rest and HRRes (R = .79, p < .01). LnRMSSDPre-Post was positively correlated with HRRes (R = .47; p < .05) HRSFGT-Rest (R = .70; p = .01) and HRPost-Rest (R = .84; p < .01). There was also a significant inverse correlation between HRPost-Rest and HRR60 (R = -.46; p < .05). Greater height and fat-free mass were favorably associated with HRSFGT-Res (R2 = .57; p = .02), HRRes (R2 = .55; p = .003) and HRPost-Rest (R2 = .59; p = .02). Height was also associated with attenuated depression of LnRMSSDRest-Post. After accounting for the effect of other independent variables in the multiple linear regression models, height was the only significant predictor for HRSFGT-Rest (β = -.90), HRRes (β = -.64), HRPost-Rest (β = -.76) and LnRMSSDRest-Post (β = -.06). A significant decrease in HRRes (80.1 ± 6.7% vs. 76.0 ± 6.7%; p < 0.001) and increase in HRR60 (29.4 ± 8.3 b∙min-1 vs. 37.8 ± 9.0 b∙min-1; p < .001) were observed after the physical training intervention. There was a significant correlation between maximal pace SFGT time and the standardized pace SFGT HRR60 (R = -0.70; p = 0.02), but not with other dependent variables. In summary, these findings indicate that greater cardiovascular demand during fire ground tasks is related to greater physical stress and lower parasympathetic activity during recovery. Greater height and fat-free mass as well as physical training are associated with lower physiological stress and accelerated recovery from fire ground tasks. Support for relationships between work capacity and heart rate dynamics during a standardized submaximal pace SFGT is limited, indicating that independent SFGT conditions may be necessary to provide work capacity and health information, respectively.
239

Resource control strategies: Associations with autonomic nervous system reactivity

Holterman, Leigh Ann 01 January 2018 (has links)
Social dominance is an inherent component of human social organization (Hawley, 1999, Ryff & Singer, 2000; Uchino, Cacioppo, & Kiecolt-Glaser, 1996). Some behaviors typically associated with gaining dominance (e.g., bullying, aggression), have been linked with maladaptive outcomes (Hawley, 2016). However, Resource Control Theory (RCT) highlights the adaptive role of the prosocial (e.g., sharing, cooperating) and the coercive (e.g., taking, threatening) strategies that youth use to gain resources within their peer group (Hawley, 2003a). These behaviors may have important implications for individuals’ physiological stress reactivity, particularly during middle childhood when youth are undergoing rapid cognitive and social development (Parker et al., 2006). The overall goal of the current study was to examine whether patterns of prosocial and coercive resource control strategy use were associated with autonomic nervous system reactivity in a sample of 9-12 year old children. Specifically, this study used person-centered analyses to investigate whether membership in groups based on resource control strategy use was associated with measures of autonomic nervous system reactivity (i.e., skin conductance [SCL-R], heart rate [HR-R], and systolic and diastolic blood pressure [SBP-R, DBP-R, respectively]). This study also utilized variable-centered analyses to investigate whether coercive resource control strategies were associated with these measures of autonomic nervous system reactivity, and whether this relationship was moderated by prosocial resource control strategies. This study also investigated whether these associations were present in the context of social and non-social stressor tasks. One hundred children (50% female, Mage = 10.47 years) and one of their parents participated in the current study and were recruited from the community in a small northeastern city. Participants’ SCL-R, HR-R, SBP-R, and DBP-R were assessed using a stress protocol during which they discussed an experience of relational victimization (e.g., being left out), played an online ball-tossing game designed to mimic social exclusion experiences, and completed a mirror-tracing task. Levels of prosocial and coercive resource control strategy use were gathered using parent report. Findings suggested that, during the discussion of a relational victimization experience, the association between coercive control strategies and HR-R was moderated by prosocial control strategies. Specifically, for those low in prosocial control strategies, lower coercive control strategies were associated with increased HR-R. In contrast, in the context of the online ball-tossing game, the associations between coercive control strategies and both SBP-R and DBP-R, respectively, were moderated by prosocial control strategies. Specifically, for those low in prosocial control strategies, higher coercive control strategies were associated with both increased SBP-R and DBP-R. No other outcome measures were associated with main effects of resource control strategies or an interaction between coercive and prosocial control strategies. These patterns suggest that resource control strategy use may be differentially related to HR-R and blood pressure reactivity. Additionally, this pattern may have resulted from differences in the characteristics of the social stressor tasks. Though more research is needed, this study provides the first step in investigating the associations between resource control strategies and long-term physical health in children. This may have important implications for the development of intervention and prevention programs that will help improve the physical health of youth.
240

The Emotional Congruence of Experience and Bodily Change

Reeder, Matthew, res.cand@acu.edu.au January 2001 (has links)
This study examined the association of the experience of emotion and somatic changes. The study compared reported somatic changes generally experienced when anxious with the actual association of the experience of emotion and somatic changes as measured during a specific event. Emotions were measured as both general negative emotion as well as specific emotions: anger, disgust, fear, sadness and shame. Participants were volunteers from a Victorian university who agreed to watch a video depicting the dramatisation of child abuse. Throughout the video, participants indicated their experience of emotion. Measures were also taken throughout the procedure of facial expression and Galvanic Skin Response (GSR). In order to examine emotional-congruence, subjects were divided into three groups. These groups were divided according to the congruence of subjects’ experienced emotion with autonomic changes and facial expressivity. Groups were divided separately for each of the emotion types. Where there was little difference between the reported experience of emotion and that, which would have been expected from the observed somatic changes, the subject was deemed to be in the Congruent Group. Subjects whose reported experience of emotion was greater or less than would be expected from observed somatic changes were allocated to the Over-reporter and Under-Reporter Groups respectively. This data was then compared to participants’ reports of the number of somatic symptoms usually experienced when anxious. It was found that participants who under-report the experience of general negative-emotion compared with their observed somatic changes (both GSR and facial expressivity) had lower trait-somatic-anxiety (reported fewer somatic symptoms usually experienced when anxious). There was no significant difference between the Congruent Group and Over-Reporter Group. The Under-Reporter Groups had significantly lower trait-somatic-anxiety than the Congruent Group when emotional-congruence was defined by fear and GSR, anger and GSR and sadness and facial expressivity. The actual association of shame and disgust with either somatic change, sadness with autonomic change and anger and fear with facial expressivity was unrelated to the number of somatic symptoms reported to be usually experienced when anxious. The results supported the idea that subjective reports of the number of somatic symptoms reported to be usually experienced when anxious reflect the actual association of somatic change and experience, but with limitations. The actual association of experience of fear with autonomic change seems to reflect the number of somatic symptoms reported to be usually experienced when anxious more than other emotions. Further for those for whom the experience of anger and negative-emotion has a greater association with somatic change, there was a greater number of somatic symptoms reported to be usually experienced when anxious. This would suggest that some people have a greater association of some experiences of emotion and somatic change. Furthermore, while there is an association between reported somatic changes generally experienced when anxious with the actual association of the experience of emotion and somatic changes as measured during a specific event, this was dependant on the association of the emotion types rather than being generalised for all emotions.

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