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Efeitos da simpatectomia no miocárdio / Sympathectomy effects upon myocardiumJordão, Mauricio Rodrigues 29 June 2017 (has links)
A simpatectomia é uma modalidade terapêutica ampla e consagrada há décadas para determinadas patologias. Recentemente, alguns trabalhos sugerem a aplicação de tal técnica no tratamento da insuficiência cardíaca. Contudo, seus efeitos fisiológicos cardíacos em modelos experimentais foram pouco estudados. O objetivo deste trabalho é avaliar os efeitos fisiológicos da simpatectomia no coração. Para tal, foi utilizado o modelo experimental de simpatectomia em ratos pela técnica de esclerose do gânglio estrelado por punção e injeção de álcool absoluto. O estudo avaliou cinco grupos: controle (15 animais), simpatectomia unilateral esquerda (15 animais), simpatectomia bilateral (31 animais), simpatectomia unilateral esquerda com atenolol (15 animais) e atenolol sem simpatectomia (15 animais). Foram avaliadas as variáveis relacionadas ao sistema nervoso autônomo, como propriedades cronotrópicas em repouso e ao esforço, modulação autonômica cardiovascular, catecolaminas miocárdicas e periféricas e receptores beta-adrenérgicos do miocárdio. Também foram analisados os efeitos na função ventricular e no tamanho do miócito. As variáveis propostas para análise foram obtidas por ECG de repouso, ecocardiograma, teste de esforço máximo, frequência cardíaca ao esforço e variabilidade da FC e da PAS avaliadas no domínio do tempo e da frequência. As informações do miocárdio quanto a receptores, catecolaminas miocárdicas, catecolaminas periféricas e tamanho dos miócitos foram obtidas por PCR, ELISA, HPLC e morfometria do miócito, respectivamente. Este estudo evidenciou que os animais do grupo bilateral apresentam maiores níveis de catecolaminas periféricas e, consequentemente, são mais taquicárdicos e hipertensos. Os achados sugerem a ativação, neste grupo, de uma via compensatória que pode ter efeitos deletérios / Sympathectomy is a therapeutic modality used to treat certain diseases during decades. Recently, some studies suggest the application of this technique in the treatment of heart failure. However, its physiological effects upon the heart have been slightly studied. The objective of this study was to evaluate the physiological effects of sympathectomy in the heart. For this purpose, we used the experimental model of sympathectomy in rats by stellate ganglion sclerosis technique starring puncture and absolute alcohol injection. The study evaluated five groups of wistar rats: control (15), left unilateral sympathectomy (15), bilateral sympathectomy (31), left unilateral sympathectomy with atenolol (15) and atenolol without sympathectomy (15). We assessed variables related to the autonomic nervous system, such as chronotropic properties at rest and stress, cardiovascular autonomic modulation, myocardial and peripheral catecholamines and beta-adrenergic receptors in the myocardium. As well, we studied the effects on ventricular function and myocyte size. The proposed variables for analysis were obtained by resting electrocardiogram, echocardiography, maximal exercise test, heart rate at exercise and heart rate and systolic blood pressure variability in the time and frequency domain. The myocardial receptors, myocardial and peripheral catecholamines and myocyte size were obtained by PCR, ELISA, HPLC and myocyte morphometry, respectively. This study showed that the animals in the bilateral group had higher levels of peripheral catecholamine and, consequently, a higher heart rate and blood pressure. These findings suggest the activation of a compensatory pathway in the sympathectomy group that may have deleterious effects
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Efeito do treinamento físico nos aspectos psicossociais, modulação autonômica e inflamação pulmonar em pacientes com asma persistente moderada ou grave / Effect of physical training on psychosocial factors, autonomic modulation and pulmonary inflammation in patients with moderate or severe persistent asthmaMendes, Felipe Augusto Rodrigues 21 January 2010 (has links)
A asma é uma doença com alta prevalência e leva a importantes danos funcionais à saúde e à qualidade de vida do paciente. A fisiopatologia da doença está centrada na inflamação crônica das vias aéreas que associada a uma disfunção do sistema nervoso autônomo (SNA) favorece a hiper-reatividade e à obstrução brônquica. O treinamento físico pode modular a resposta autonômica e imune em indivíduos saudáveis e a sua prática de maneira regular também é recomendada para os pacientes asmáticos. Porém, permanece pouco compreendido o efeito do treinamento físico sobre a inflamação pulmonar e a modulação autonômica, bem como nos aspectos psicossociais e sintomatologia em pacientes asmáticos. Objetivo: Avaliar o efeito de um programa de treinamento físico aeróbio na inflamação pulmonar, resposta autonômica, fatores relacionados à qualidade de vida (FRQV) e sintomatologia de pacientes adultos com asma persistente moderada ou grave. Casuística e Métodos: Foram estudados 53 adultos asmáticos divididos aleatoriamente nos grupos controle (GC; n=27) e treinado (GT; n=26). Os pacientes do GC (programa educacional + exercícios respiratórios) e GT (similar ao GC + treinamento aeróbio) foram acompanhados durante 3 meses, 2 vezes semanais. A capacidade aeróbia máxima (VO2max), função pulmonar, escarro induzido, fração de óxido nítrico no ar exalado (FeNO), variabilidade da frequência cardíaca (VFC) e 17 FRQV foram analisadas antes e após o treinamento. Os dias com sintomas foram avaliados mensalmente. Resultados: Observamos que os pacientes do GT apresentaram redução da FeNO e do número de eosinófilos no escarro induzido, um aumento do VO2max e a uma melhora dos fatores relacionados à qualidade vida e sintomas de asma (p<0,05). Nenhuma mudança foi observada na função pulmonar e VFC para ambos os grupos após o treinamento. Conclusão: Nossos resultados sugerem que um programa de treinamento físico é capaz de melhorar o condicionamento cardiorrespiratório, a qualidade de vida e reduzir a inflamação pulmonar sem influenciar o comportamento do SNA de pacientes asmáticos. / Asthma is a disease with a high prevalence leading to important impairment on patients functional status and health and quality of life. Asthma pathophysiology is centered on chronic airway inflammation that associated with a dysfunction in the autonomic nervous system (ANS) increases bronchial hyperactivity and obstruction. In healthy subjects, the physical training can modulate autonomic and immune systems and its regular practice is recommended for asthmatic patients. However, it remains poorly known the effect of the physical training on airway inflammation and autonomic modulation as well as on psychosocial factors and clinical management of asthmatic patients. Objective: To evaluate the effects of an aerobic training program on airway inflammation, ANS and health related quality of life (HRQL) in adult patients with moderate or severe asthma. Methods: Fifty-tree asthmatic adult patients were randomly assigned to either control (CG; n=27) or training groups (TG n=26). Patients in CG (educational program + respiratory exercises) and TG (similar to control group + aerobic training) were followed twice a week during a 3-month period. Maximal aerobic capacity (VO2max), pulmonary function, induced sputum, fractional concentration of exhaled nitric oxide (FeNO), heart rate variability (HRV) and HRQL were evaluated before and after treatment. Asthma symptoms were evaluated monthly. Results: Our results show that patients from the TG presented a decrease on FeNO and number of eosinophils in the induced sputum, a increased on 19 VO2max and a improvement of HRQL and asthma symptoms (p<0.05). No change was observed in lung function and HRV in both groups after treatment. Conclusion: Our results suggest that a physical fitness program can improve aerobic capacity, quality of life and reduce airway inflammation, however without any influence on ANS in asthmatic patients.
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Estudo da variabilidade da frequência cardíaca durante o período de recuperação pós-exercício em pacientes hipertensos - efeito do treinamento físico / Study of heart rate variability during the recovery after exercise in hypertensive patients - effect of physical trainingAlmeida, Daniel Salvini de 25 November 2016 (has links)
Sabe-se que a hipertensão arterial está intimamente ligada a prejuízos no controle autonômico cardiovascular, caracterizado pelo maior predomínio do componente autonômico simpático e redução no componente autonômico vagal. Dessa forma, o objetivo do presente estudo foi avaliar o comportamento da variabilidade da frequência cardíaca durante o período de recuperação em homens e mulheres, bem como os efeitos promovidos pela prática do exercício físico nesses indivíduos hipertensos. Para tanto, foram utilizados dados de 21 voluntários hipertensos e sedentários com média de idade de 49?9,8 anos, divididos em 2 grupos distintos, homens (n=10) e mulheres (n=11). Todos os indivíduos foram submetidos a um protocolo de treinamento físico aeróbio em esteira, 3 vezes por semana, durante 12 semanas, com duração de 45 minutos, e intensidade fixada na frequência cardíaca obtida a 5% abaixo do limiar anaeróbio respiratório obtido no teste ergoespirométrico (Protocolo de Bruce Modificado). Ao final do treinamento de 12 semanas a capacidade aeróbia (VO2pico) foi novamente avaliada. O registro para análise espectral da VFC foi realizado entre 09h00min e 10h00min da manhã, obedecendo ao seguinte protocolo; após 20 minutos em repouso na posição supina em uma maca inclinável, os voluntários foram colocados passivamente na posição inclinada a 75 graus durante mais 20 minutos. O registro da FC na posição supina e durante o tilt test foi realizado por meio do eletrocardiograma, do qual foram obtidas as séries temporais oriundas da medida do tempo entre os intervalos das ondas R-R. Para a análise estatística foi utilizada a comparação entre dois grupos, ou no mesmo grupo, antes e após, foi utilizado o teste \"t\" de Student; Quando a distribuição não era normal foram utilizados testes não-paramétricos. Na comparação entre dois grupos foi utilizado o teste de Mann-Whitney. Foram consideradas estatisticamente significantes P era menor que 5%. Os resultados mostraram que o treinamento físico aeróbio no grupo Total-pós apresentou reduções significativas da pressão arterial sistólica (PAS) e da pressão arterial média (PAM). A associação entre os sexos mostrou aumento da FC basal. Já quando comparado os sexos separadamente, também foi observado diminuição da PAS no grupo Homem-pós em relação ao grupo Homem-pré, enquanto que nas mulheres essa redução ocorreu apenas na pressão arterial diastólica (PAD). Em relação aos valores antropométricos, houve diferença estatistica apenas no parâmetro altura entre os grupos Mulheres-pré e Homens-pré. Os resultados do 6º minuto da recuperação não apresentaram diferenças estatisticamente significantes quando comparado os grupos, Total, Homens e Mulheres. Entretanto, quando se faz a associação entre os grupos Mulheres-pós e Homens-pós, foi observado uma redução da banda de LF(ms2). Apesar do HF(ms2), também ter tendido a diminuir, não houve relação estatística. Em relação a avaliação por meio da análise simbólica, os resultados mostraram redução nos valores de 2LV no grupo Mulheres-pós. A análise dos resultados do 6º ao 12º min no grupo Total não mostraram diferenças significantes em nenhum parâmetro analisado. Da mesma forma, quando comparamos os sexos separadamente, também não observamos diferenças estatisticamente significantes entre eles. Já quando analisamos os valores da análise simbólica, também não observamos diferenças no grupo Total tanto pré quanto pós treinamento. Ao verificar os resultados obtidos no grupo Homens-pós houve aumento do 0V em relação ao grupo Homens-pré. Os resultados inter grupos também mostraram aumento dos parâmetros 0V e 0V/2V no grupo mulheres-pré quando comparado ao grupos Homens-pré. Diferentemente, os valores de 1V, 2LV e 2V apresentaram reduções significativas também no grupo Mulheres-pré em relação ao grupo Homens-pré. Os resultados no 12º min do grupo Total pré e pós não apresentaram diferença na analise espectral entre eles. Entretanto, quando comparamos inter grupos, o grupo Mulheres-pós apresentou uma redeução da banda de LF (ms2) quando comparado ao grupo Homem-pós, já os demais parâmetros não foram diferentes.Para os valores da análise simbólica observamos apenas diminuição do parâmetro 2LV no grupos Mulheres-pós quando comparado ao grupo Homens-pós. Os demais resultados não apresentaram reduções significantes. Assim, concluimos que o treinamento físico aeróbio promoveu a redução dos parâmetros hemodinâmicos nos grupos analisados. Além disso, embora observamos que a FC de recuperação foi semelhante entre os grupos, a VFC na recuperação no 6 e no 12º minutos apresentou maior recuperação no grupo das mulheres / It is known that hypertension is closely linked to losses in cardiovascular autonomic control, characterized by the predominance of the sympathetic autonomic component and reduced vagal autonomic component. Thus, the aim of this study was to evaluate the behavior of heart rate variability during the recovery period in men and women, as well as the effects caused by physical exercise in these hypertensive individuals. For this, we used data of 21 hypertensive and sedentary volunteers with a mean age of 49?9,8 years, divided into two distinct groups, men (n = 10) and women (n = 11). All subjects underwent a physical training protocol on a treadmill three times a week for 12 weeks, with 45 minutes duration, and intensity fixed heart rate obtained 5% lower respiratory anaerobic threshold obtained in the cardiopulmonary exercise test (Bruce Amended Protocol). At the end of 12 weeks of training aerobic capacity (VO2 peak) was again evaluated. The record for spectral analysis of HRV was performed between 09:00 and 10:00 am, according to the following protocol; after 20 minutes of rest in supine position on a tilt stretcher, the volunteers were passively placed in position tilted at 75 degrees for 20 minutes. The HR record in the supine position and during the tilt test was performed by the electrocardiogram, which were obtained from the time series derived from the measurement of time intervals between the waves R-R. For statistical analysis was used to compare two groups, or in the same group before and after, we used the \"t\" test of Student; When the distribution was not normal non-parametric tests were used. Comparing two groups we used the Mann-Whitney test. statistically significant were considered P was less than 5%. The results showed that aerobic exercise training on Total-post group showed significant reductions in systolic blood pressure (SBP) and mean arterial pressure (MAP). The association between the sexes showed increased basal FC. But when comparing the sexes separately, it was also observed reduction in SBP in group-Man post in relation to the group pre-Man, while in women this reduction occurred only in diastolic blood pressure (DBP). Regarding the anthropometric values, there was statistical difference only in the height parameter between Women and Men-pre-pre groups. The results of the 6th minute of recovery showed no statistically significant differences when comparing the groups Total, Men and Women. However, when making the association between Women and Men-postpost groups, it was observed a reduction in band LF (ms2). Despite the HF (ms2), also have tended to decline, there was no statistical relationship. In relation to evaluation through the symbolic analysis, the results showed reduction in 2LV values in Womenpost group. The results of the 6th to the 12th min Total group showed no significant differences in any parameter analyzed. Similarly, when comparing the sexes separately, we did not observe statistically significant differences between them. But when we analyze the values of symbolic analysis showed no difference in the Total group both pre and post training. When checking the results of the Men-post group there was an increase of 0V compared to pre-Men group. The results also showed increased inter groups of parameters 0V and 0V / 2V women in the group pre-Men when compared to pre-groups. In contrast, the values of 1V, 2V and 2LV also showed significant reductions in pre-Women group in relation to pre-Men group. The results after 12 min Total pre and post group showed no difference in spectral analysis between them. However, when compared inter groups, the Women-post group showed a reduction band LF (ms2) compared to man-post group, since the other parameters were not different. For the values of symbolic analysis we observe only decrease parameter 2LV Women in post-groups when compared to men-after group. The other results showed no significant reductions. Thus, we conclude that aerobic physical training promoted reduction of hemodynamic parameters in the analyzed groups. Moreover, although we note that the FC recovery was similar between groups, HRV recovery at 6 and after 12 minutes showed higher recovery in the women\'s group
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Evaluation of the Effects of Hyperbaric Dive Environments on the Autonomic Nervous System Using Principal Dynamic Mode AnalysisBai, Yan 11 August 2011 (has links)
"As water covers over 75% surface area of the earth, humans have an innate desire to explore the underwater environment for various aims. Physiological responses are induced in humans and animals to adapt to different stresses imposed by the hyperbaric environment. When these stresses become overwhelming, certain hazards can occur to individuals in underwater or in similar hyperbaric environments, and they may include nitrogen narcosis, oxygen toxicity and decompression sickness (DCS). There are evidences showing that the autonomic nervous system (ANS) plays an important role in diving reflex and physiological responses to diving hazards. However, the assessment of the autonomic nervous activity during SCUBA dives and diving-related hazards are mostly absent from the literature. Thus, in order to evaluate the autonomic nervous alterations that may occur during diving, especially during DCS, the following three experiments were performed in this study: the simulated dives of human subjects in a hyperbaric chamber, the SCUBA diving performed in seawater and induced decompression sickness in a swine model. A novel algorithm developed in our lab, principal dynamic mode (PDM) analysis, is applied to the above data. It has been shown that the PDM is able to accurately separate the sympathetic and parasympathetic dynamics of the ANS, and subsequently it is able to obtain a better quantification of the autonomic nervous activity than a current golden-standard approach. Through the study, dominance of the parasympathetic modulation was found in both hyperbaric chamber and SCUBA diving conditions. And more stresses were present in real dives, compared to simulated dives in chamber. In the swine DCS model, we found neurological DCS and cardiopulmonary DCS resulted in different alterations in the ANS. Furthermore, tracking dynamics of the parasympathetic modulations via the PDM method may allow discrimination between cardiopulmonary DCS and neurological DCS, and has potential use as a marker for early diagnosis of cardiopulmonary DCS. "
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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 fibromyalgiaLúcia Helena de Góes Necchi 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.
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EFEITO DO TREINAMENTO AERÓBIO NOS PARÂMETROS CARDIOVASCULARES DE PACIENTES EM HEMODIÁLISE / EFFECT OF AEROBIC TRAINING IN PARAMETERS CARDIOVASCULAR PATIENTS IN HEMODIALYSISAZOUBEL, Luana Manaisse 05 May 2017 (has links)
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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.
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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 fibromyalgiaNecchi, 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.
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On the development of the parasympathetic, enteric and sacral nervous systems / Sur le développement des systèmes nerveux parasympathique, entérique et sacréEspinosa 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.
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HEART RATE DYNAMICS DURING AND AFTER SIMULATED FIRE GROUND TASKS: EFFECTS OF PHYSICAL FITNESS AND TRAININGSaari, 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.
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Resource control strategies: Associations with autonomic nervous system reactivityHolterman, 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.
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