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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.
331

Avaliações autonômicas e cardiovasculares em pessoas com lesão da medula espinhal nas situações de repouso, em um teste de estresse mental e durante exercício físico / Assessments autonomic and cardiovascular in people with spinal Cord injury in rest, in a test of mental stress and during physical exercise

Flores, Lucinar Jupir Forner, 1980- 02 March 2012 (has links)
Orientador: José Irineu Gorla / Tese (doutorado) ¿ Faculdade de Educação Física, Universidade Estadual de Campinas / Made available in DSpace on 2018-08-19T17:11:47Z (GMT). No. of bitstreams: 1 Flores_LucinarJupirForner_D.pdf: 1031561 bytes, checksum: bdd366b463afab5bb41f591f0bb99d60 (MD5) Previous issue date: 2012 / Resumo: O objetivo do presente estudo foi avaliar as respostas autonômicas e cardiovasculares em pessoas com lesão da medula espinhal (PLME) praticantes de Rugby em Cadeira de Rodas (RCR) em diferentes situações. A amostra foi composta de dez (10) tetraplégicos do sexo masculino com média de idade de 29,6 ± 6,5 anos. As coletas foram realizadas na UNICAMP, com a aprovação do Comitê de Ética em Pesquisa sob-protocolo nº 276/2010. Foram realizadas avaliações antropométricas. A potência aeróbia (PA) foi estimada por um teste máximo de quadra com duração de 12 minutos. A Pressão arterial (PAS) verificada pelo método auscultatório e o registro da variabilidade da PAS (VPAS) através do equipamento Finometer® (Finapress©). Avaliações da VFC foram realizadas com os sujeitos sentados nas cadeiras próprias (repouso, estresse mental e exercício). O Stroop Test foi utilizado como teste de estresse mental (TEM). Para o registro de informações da VFC foi usado o frequencímetro modelo RS800CX-POLAR© e posteriormente foi utilizado o software da Polar© para análise dos dados. Os dados foram apresentados em média±desvio padrão. Para análise estatística foi utilizado o software INSTAT®. Valores de p<0,05 foram considerados significativos para diferenças entre situações de avaliação. O tempo de lesão medular foi de 7,5 ± 4,1 anos. Quanto à massa corporal e estatura dos sujeitos, foi verificada média de 64,5 ± 6,2 kg e 1,75 ± 0,09 m. O índice de massa corporal foi de 21 ± 1,4 kg/m2. Já o percentual de gordura (DXA) foi de 21± 5,4%. O valor médio da distância percorrida no teste de 12 min, para a estimativa da PA foi de 1579,5 ± 439,1 m. O valor médio para a PA estimada correspondeu a 18,03 ± 8,1 ml/kg/min-1. Valores de FC e PAS foram significativamente maiores ao final do teste de 12 min quando comparados aos valores de repouso e recuperação. Resultados de FC ao longo do teste de estresse mental revelaram-se maiores que os valores de FC iniciais do registro. A PAS não apresentou diferenças entre as avaliações de repouso e estresse mental, assim como os valores de VFC não apresentaram diferenças significativas nestas situações. Valores do balanço autonômico da VFC também não apresentaram diferenças quando comparado valores iniciais e no teste de estresse mental (BF, AF e BF/AF). Já em exercício a VFC apresentou diferenças, assim como os valores de BF, AF e BF/AF quando comparado aos valores pré e pós exercício. A VPAS apresentou-se reduzida pós exercício físico, assim como a PASist e o índice de BF quando comparados aos valores pré exercício físico. Estes resultados indicam que a amostra estudada apresenta potência aeróbia dentro da normalidade para esta população. O % de gordura foi menor do que outros estudos com tetraplégicos. Ocorreram alterações durante o exercício físico nos componentes da VFC e VPAS semelhantes aos de outros estudos com tetraplégicos - (repouso x TEM x pós exercício físico). Há indícios de menores prejuízos neste grupo estudado em relação aos danos no controle autonômico da circulação, provavelmente por esta amostra participar de programa de treinamento físico / Abstract: The purpose of this work was to evaluate the autonomic and the cardiovascular responses in people with spinal cord injury (PLME) the players of Wheelchair Rugby (RCR) in different situations. The sample was composed of ten (10) tetraplegics male. The samples were collected in Campinas, with the approval of the Committee of Ethics in the Research with the protocol 276/2010. In this work was performed anthropometric evaluation. The aerobic power (AP) was estimated by a max court test that didn't exceed 12 minutes. The blood pressure (BP) verified by auscultation and registration of the BP variability (BPV) through an equipment called Finometer® (Finapress©).The evaluation of heart rate variability (HRV) were made with the individuals sitting on their chairs (rest, mental stress test and exercise). The Stroop Test was used as a test of mental stress. For recording of information of the HRV was used frequency counter model RS800CX-POLAR© and afterward was used Polar© software for data analysis. The data were expressed as average±standard deviation. To the statistical analysis was performed using the INSTAT® software. p values<0.05 were considered statistically significant differences between the situations of evaluation. The average age of the individuals was 29.6 ± 6.5 years old and the time of spinal cord injury was 7.5± 4.1 years. As for weight and height of them, there was an average of 64.5 ± 6.2 kg and 1.75 ± 0.09 m. The body mass index was 21 ± 1.4 kg/m2. The fat percentage (DXA) was 21 ± 5.4%. Results revealed that the test for 12 min, the distance rode to the PA estimate was 1579.5 ± 439.1 m. It was verified that the estimated value of AP is 18.03 ± 8.1 ml/kg/min-1. The HR and the BP values were significantly higher at the end of the test 12 min when compared to the values of resting and recovery. The results of FC along the mental stress test, proved to be larger than the values of initial HR of the record. The BPV did not show differences between the evaluations of rest and mental stress, as well as the values of HRV were not significantly different in these situations. Values of the autonomic balance of the HRV also showed no differences when compared to initial values and mental stress test (LF, AF e LF/HF). In the exercise the HRV presented discrepancies as well as the heart rate variability showed differences as well as the values of LF, HF e LF/HF when compared to pre and post exercise. The VBP presented the reduced as well as SBP and the values of BF compared before and after exercise. These results indicate that the sample presents aerobic power within the normal range for this population. The percentage of fat was lower than other studies with tetraplegics. Changes during exercise in HRV components and BPV similar to other studies with tetraplegics - (resting x TEM x post exercise). We can still consider that exist evidence of minor damage in relation to damage to the autonomic control of circulation, probably because this sample participate in physical training program / Doutorado / Atividade Fisica, Adaptação e Saude / Doutor em Educação Física
332

Variabilidade da frequência cardíaca após treinamento concorrente = comparação entre homens e mulheres de meia-idade = Heart rate variability after concurrent training : comparison between middle-aged men and women / Heart rate variability after concurrent training : comparison between middle-aged men and women

Antunes, Melissa, 1983- 05 April 2012 (has links)
Orientador: Mara Patrícia Traina Chacon Mikahil / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Física / Made available in DSpace on 2018-08-20T15:04:08Z (GMT). No. of bitstreams: 1 Antunes_Melissa_M.pdf: 1711920 bytes, checksum: 375abf471bd7eb2613a89fe1a745a1b7 (MD5) Previous issue date: 2012 / Resumo: A disfunção do sistema nervoso autonômico e o aumento de doenças crônico- degenerativas se manifestam junto ao processo de envelhecimento, levando à alterações da modulação autonômica cardíaca, e consequentemente da variabilidade de freqüência cardíaca. Com relação à resposta dos sistemas nervoso autônomo e cardiorrespiratório as respostas adaptativas são ainda menos esclarecedoras evidenciando-se os questionamentos quanto à carga ideal de treinamento para a aquisição de adaptações proporcionais aos protocolos de treinamento isolados. Adaptações autonômicas decorrentes do treinamento físico aeróbio já são bem estabelecidas pela literatura, como a ocorrência da bradicardia de repouso e melhorias nos índices de variabilidade da frequência cardíaca. Contudo, outros tipos de treinamento, como o treinamento concorrente, que associa o treinamento com pesos junto ao treinamento aeróbio, são questionados sobre as adaptações obtidas. Este trabalho objetivou avaliar as adaptações autonômicas em resposta ao treinamento concorrente em homens e mulheres entre 40 e 60 anos, com hábitos de vida não ativos. Os voluntários foram subdivididos em 4 grupos, sendo um de treinamento concorrente para homens (TCH), um de treinamento concorrente para mulheres (TCM), grupo sedentário homens (SH) e grupo sendentário mulheres (SM). Antes e após 16 semanas do protocolo experimental, os voluntários foram submetidos à avaliação dos componentes autonômicos cardiovasculares expressos pela variabilidade da frequência cardíaca (no domínio do tempo e da freqüência), obtidos e analisados por meio dos registros dos intervalos RR do eletrocardiograma coletados em repouso supino e em respiração espontânea. Para avaliação da aptidão cardiorrespiratória (VO2pico) foi realizado um protocolo de rampa, em esteira rolante, com incrementos crescentes de velocidade até a exaustão. A força muscular foi avaliada por meio do teste de uma repetição máxima (1-RM). Dentre os resultados obtidos, foi possível verificar que o programa de treinamento concorrente proposto parece não alterar e não interferir negativamente nas variáveis cardiovasculares de repouso. Para nenhum dos grupos estudados foi verificada redução da frequência cardíaca de repouso, da pressão arterial, nem alterações nas variáveis autonômicas cardíacas. Além disso, na avaliação cardiorrespiratória, o TCH e o TCM apresentaram melhora significativa para o VO2pico (TCH = pré: 31,63±5,37 e pós: 35,78±5,23ml/kg/min; TCM = pré 26,18±3,00 e pós: 28,41±2,34). Para o grupo TCM ganhos semelhantes foram observados quando o percentual de modificação foi calculado. Já o componente da força muscular houve melhora significativa para o grupo TCH nos três exercícios testados (supino pré: 68,88±5,79 e pós: 86,13±9,78 kg; leg press pré: 190,63±28,02 e pós: 315,25±67,74 kg; rosca direta pré: 36,75±3,06 e pós: 46,50±4,69 kg) e para o TCM em apenas dois exercícios testados (supino pré: 39,87±4,58 e pós: 46,75±6,62 kg; rosca direta pré: 23,50±3,81 e pós: 26,00±2,13 kg). Desta forma, o treinamento concorrente parece ser uma boa alternativa como metodologia de treinamento e ganhos associados nas várias capacidades físicas estudadas, porém não causou alterações na função cardiovascular. Investigações adicionais são necessárias para estabelecer o efeito dos treinamentos com pesos e concorrente nas variáveis cardiovasculares de repouso / Abstract: The autonomic nervous system dysfunction and the increase in chronic degenerative diseases are manifested by the aging process, leading to changes of the autonomic modulation cardiac, and therefore the heart rate variability. Regarding the response of the autonomic nervous system and cardiorespiratory adaptive responses are even less enlightening evidencing the questions regarding the optimal training load for the acquisition of proportional adjustments to the training protocols alone. Autonomic adjustments resulting from physical training are already well established in the literature, such as the occurrence of bradycardia at rest and improvement in indices of heart rate variability. However, other types of training, such as concurrent training, combining weight training with aerobic training, are asked about the changes obtained. This study aimed to evaluate the autonomic adaptations in response to concurrent training in men and women between 40 and 60 with non-active lifestyle. The volunteers were divided into four groups, one with concurrent training for men (TCH), one with concurrent training for women (TCM), group sedentary men (SH) and group sedentary women (SM). Before and after 16 weeks of the experimental protocol, subjects underwent evaluation of cardiovascular autonomic components expressed by heart rate variability (time domain and frequency), obtained and analyzed through the records of the electrocardiogram RR intervals collected at rest supine and breathing spontaneously. To evaluate the cardiorespiratory fitness (VO2peak) was performed a ramp protocol on a treadmill with increasing speed increments until exhaustion. Muscle strength was assessed by testing one repetition maximum (1-RM). Among the results, it was verified that the proposed concurrent training program do not seem to change and do not adversely affect the cardiovascular variables at rest. None of the groups was verified reduction in resting heart rate, blood pressure, or changes in autonomic variables. Moreover, in cardiorespiratory evaluation, TCH and TCM showed significant improvement for VO2peak (TCH = pre: 31,63 ± 5,37 and after: 35,78 ± 5,23ml/kg/min; TCM pré 26,18 = ± 3,00 and after: 28,41 ± 2,34ml/kg/min). For the group TCM similar gains were observed when the percentage change was calculated. Since the component of muscle strength significantly improved for the TCH arm in the three exercises tested (supine before: 68,88 ± 5,79 and after: 86,13 ± 9,78 kg, leg press before: 190,63 ± 2,28 and after: 315,25 ± 67,74kg; before arm curl : 36,75 ± 3,6 and after: 46,50 ± 4,69kg) and the TCM in just two exercise tested (supine before: 39,87 ± 4,58 and after: 46,75 ± 6,62 kg); before arm curl: 23,50 ±3,81 and after: 26,00 ± 2,13 kg .) Thus, concurrent training seems to be a good alternative training methodology and gains in the various physical capabilities assessed, but did not cause changes in cardiovascular function. Further investigations are needed to establish the effect of weight training and competing in cardiovascular variables at rest / Mestrado / Atividade Fisica Adaptada / Mestre em Educação Física
333

Application of real-time HRV biofeedback in the scenario of meditation practice : Feasibility, usability and medical fidelity

Gunzenhauser, Jan January 2015 (has links)
Chronic stress is a prevalent and universally present hazard in modern society. It lowers the quality of life for individuals and significantly con- tributes to unsustainable health care costs. Therefore it is important to have natural and noninvasive ways of controlling stress. One such way is meditation, a technique which has been practiced for over five thousand years to improve stress regulation. Also, proceedings in sensing technologies lead to the discovery of biofeedback as another cost-effective technique for stress assessment and reduction. In continuation of research on real-time reflective human-computer-interfaces, this thesis combines these techniques by exploring the application of electrocardiography sensing technology in a heart rate variability (HRV) biofeedback system for the scenario of medita- tion practice. A proof-of-concept prototype was designed and implemented which quantifies stress and gives feedback on meditation effectiveness. For evaluation, a user study has been performed. Results were analysed in a systematic way to evaluate the feasibility and acceptance of the solution as well as the fidelity of HRV data that was measured during user tests. The prototype was found to be feasible in the context of technology acceptance while the fidelity of data, acquired by an algorithm for time and frequency domain analysis of HRV, was confirmed. A final conclusion is that the reflective aspect of the implemented real-time biofeedback system helps to improve regulatory capacity and thus lowers stress in individuals.
334

Interactions entre le métaboréflexe et le chémoréflexe durant différentes modalités d'exercice

Houssiere, Anne 23 November 2007 (has links)
Le thème central de ce travail a consisté en l’étude et la mise en évidence des interactions existant entre le métaboréflexe et le chémoréflexe lors de l’exercice.<p><p>L’effort physique est associé à une augmentation de la ventilation, de la fréquence cardiaque ainsi que de la pression artérielle. Ces effets sont médiés au moins en partie par l’activation du métaboréflexe musculaire, et peuvent être amplifiés par le chémoréflexe ventilatoire. Le métaboréflexe et le chémoréflexe impliquent nécessairement une activation du système nerveux orthosympathique. La fonction du métaboréflexe est d’optimaliser le transport d’oxygène à destination des muscles participant à l’exercice, ce qui s’accompagne d’une vasoconstriction dans les autres territoires vasculaires. La fonction du chémoréflexe est de maintenir la capnie et d’apporter une correction ventilatoire à l’acidose métabolique et éventuellement à l’hypoxémie survenant au cours d’efforts effectués en résistance. Une sollicitation excessive du métaboréflexe et du chémoréflexe peut limiter l’aptitude à l’effort en amplifiant les sensations de dyspnée (augmentation des équivalents ventilatoires) et en limitant le transport d’oxygène (augmentation de la pression artérielle limitant le débit cardiaque). <p><p>L’étude des adaptations cardiovasculaires et ventilatoires ainsi celles du système nerveux sympathique en réponse à un exercice réalisé en hypoxie peut se révéler intéressante à plusieurs niveaux.<p>Une telle étude devrait permettre de mieux comprendre la limitation de l’aptitude à l’effort des sujets sains en altitude. En effet, depuis plusieurs décennies, l'entraînement en altitude est fréquemment utilisé par les athlètes d'endurance. Cette méthode de préparation physique, qui consiste à séjourner et s'entraîner plusieurs semaines à moyenne altitude (2000-2800m), vise à améliorer temporairement la performance aérobie lors du retour au niveau de la mer. Cette étude pourrait également présenter un intérêt pour les travailleurs en altitude mais également de manière générale à toutes les personnes effectuant des séjours en montagne.<p>Les métaborécepteurs et les chémorécepteurs contribuent directement aux ajustements cardio-vasculaires et ventilatoires durant un exercice statique réalisé en situation d’hypoxie<p><p>C’est pourquoi, dans une première étude, nous avons souhaité différencier précisément les actions respectives du métaboréflexe et du chémoréflexe lors d’un exercice en hypoxie chez une population de sujets jeunes et en bonne santé. Nous avons donc voulu vérifier l’hypothèse selon laquelle les métaborécepteurs joueraient un rôle important dans l’activation sympathique et l’élévation tensionnelle en réponse à un exercice isométrique en hypoxie. <p>Nous avons montré que durant l’effort en hypoxie, les métaborécepteurs et les chémorécepteurs interviennent de manière différente dans les réponses sympathiques, cardiovasculaires et ventilatoires.<p>L’activation du système nerveux sympathique en réponse à un exercice en hypoxie est principalement médiée par les métaborécepteurs.<p>Ces derniers jouent également un rôle prépondérant dans l’élévation tensionnelle. <p>L’élévation de la ventilation est médiée aussi bien par les métaborécepteurs que par les chémorécepteurs.<p>Par contre, les métaborécepteurs jouent un rôle mineur dans l’élévation de la fréquence cardiaque lors d’un exercice isométrique en hypoxie.<p><p>Lors d’une deuxième étude, nous nous sommes intéressés aux effets du vieillissement sur la contribution du métaboréflexe et du chémoréflexe, toujours durant un effort en hypoxie.<p>L’âge réduit la sensibilité du métaboréflexe. Par contre, l’âge n’affecte pas le chémoréflexe. Les effets de l’âge sur l’interaction des deux réflexes sont méconnus. Nous avons donc testé l’hypothèse selon laquelle l’effort isométrique en hypoxie (maximum de stimulation métaboréflexe) chez le sujet âgé s’accompagne d’une moindre activation sympathique, d’une moindre montée de la pression artérielle, et d’une réponse ventilatoire identique par rapport à celle observée chez le sujet jeune. <p>Nous avons observé une moindre activation sympathique en réponse à l’exercice aussi bien en normoxie qu’en hypoxie chez les sujets plus âgés, subsistant lors de l’arrêt local de la circulation, permettant d’isoler la contribution du métaboréflexe lors de l’exercice.<p>Nous en avons conclu que malgré le fait que l’âge réduise la sensibilité des métaborécepteurs, ceux-ci restent des déterminants majeurs de l’activation orthosympathique lors d’un effort réalisé en hypoxie chez les sujets plus âgés.<p><p>\ / Doctorat en Sciences de la motricité / info:eu-repo/semantics/nonPublished
335

Cardiovascular autonomic function in coronary artery disease patients with and without type 2 diabetes:significance of physical activity and exercise capacity

Karjalainen, J. (Jaana) 03 December 2013 (has links)
Abstract Coronary artery disease (CAD) and type 2 diabetes (T2D) are associated with cardiovascular autonomic dysfunction, which is widely used as a predictor of mortality in cardiovascular diseases. The determinants of autonomic dysfunction in CAD patients with or without T2D are not well known. The aim of this thesis was to examine the determinants of cardiovascular autonomic function in healthy subjects and CAD patients with and without T2D. A second aim was to study the prognostic value of autonomic function in the patient population. A third aim was to study the effects of exercise prescriptions on physical activity and exercise capacity in the patient groups. The association between heart rate (HR) variability and physical activity was examined by means of 24-hour recordings in 45 healthy adults. The determinants and prognostic value of autonomic function, measured by HR recovery, HR variability, and HR turbulence, were assessed in 1060 CAD patients (50% were patients with T2D). Physical activity was measured before and after a six-month exercise prescription in 44 CAD patients without T2D and 39 CAD patients with T2D. In healthy patients, short-term HR variability indexes and the complexity properties of HR were influenced by physical activity, whereas long-term HR variability indexes remained relatively stable at various activity levels, making them robust indexes for assessment of autonomic function during ambulatory conditions. In CAD patients, exercise capacity was the most important determinant of autonomic function in addition to physical activity, age, presence of T2D, and left ventricular systolic function. During a 2-year follow-up, autonomic dysfunction predicted cardiovascular events only in CAD patients with T2D, but did not provide independent prognostic information after multivariate adjustment when high-sensitivity C-reactive protein, a marker of inflammation, remained as an independent predictor. CAD patients with T2D were physically less active than patients without T2D. Exercise prescription promoted a more active lifestyle and improved exercise capacity in both patient groups. In conclusion, cardiovascular autonomic dysfunction in CAD patients with and without T2D is closely related to low exercise capacity and physical activity, which both can be increased by exercise prescriptions. Autonomic dysfunction predicts short-term cardiovascular events only in CAD patients with T2D, but is not as strong an independent predictor as low-grade inflammation. / Tiivistelmä Autonomisen hermoston toiminnan häiriö on yleinen komplikaatio sepelvaltimotaudissa ja tyypin 2 diabeteksessa (T2D), ja sen tiedetään olevan itsenäinen kuolleisuutta ennustava tekijä. Autonomista säätelyä selittäviä tekijöitä ei kuitenkaan tunneta hyvin. Tässä tutkimuksessa selvitettiin autonomisen hermoston toimintaa selittäviä tekijöitä kolmessa ryhmässä: osa tutkittavista oli terveitä, osalla oli sepelvaltimotauti ja T2D, ja osalla pelkästään sepelvaltimotauti. Lisäksi tutkittiin, miten autonominen säätely vaikuttaa sepelvaltimotautipotilaiden ennusteeseen sekä miten liikuntaohjelma vaikuttaa heidän fyysiseen aktiivisuuteensa ja suorituskykyynsä. Sykevaihtelun ja fyysisen aktiivisuuden välistä yhteyttä selvittävään tutkimukseen osallistui 45 tervettä henkilöä. Autonomisen hermoston toimintaa selittäviä tekijöitä ja sen ennustearvoa tutkittiin 1060 sepelvaltimotautipotilaalta, joista puolet sairasti T2D:ta. Näistä potilaista valittiin satunnaisotannalla kuuden kuukauden liikuntaohjelmaan ja fyysisen aktiivisuuden mittauksiin 44 sepelvaltimotautipotilasta, joilla ei ollut T2D:ta, ja 39 potilasta, jotka sairastivat T2D:ta. Terveillä henkilöillä lyhyen aikavälin sykevaihtelumuuttujat olivat yhteydessä fyysiseen aktiivisuuteen, mutta pitkän aikavälin sykevaihtelumuuttujissa tätä yhteyttä ei havaittu. Sepelvaltimotautipotilailla vahvimmiksi autonomista säätelyä selittäviksi tekijöiksi osoittautuivat maksimaalinen suorituskyky, fyysinen aktiivisuus, ikä, T2D ja vasemman kammion ejektiofraktio. Poikkeava autonominen säätely ennusti sydän- ja verisuonitautitapahtumia kahden vuoden seurannan aikana vain T2D:ta sairastavilla sepelvaltimotautipotilailla, mutta sillä ei ollut itsenäistä ennustearvoa, kun vakioitiin muilla riskitekijöillä. Lopulta ainoa huonon ennusteen merkki oli tulehdustilaa kuvaava herkkä CRP. T2D:ta sairastavat sepelvaltimotautipotilaat olivat fyysisesti passiivisempia kuin pelkästään sepelvaltimotautia sairastavat. Yksilöllinen liikuntaohjelma lisäsi korkean intensiteetin fyysistä aktiivisuutta ja paransi suorituskykyä molemmissa potilasryhmissä. Tämän tutkimuksen tulokset osoittavat, että sepelvaltimotautipotilailla autonomisen hermoston toiminnan häiriö on yhteydessä vähäiseen fyysiseen aktiivisuuteen ja heikkoon fyysiseen kuntoon. Molempiin tekijöihin voidaan vaikuttaa positiivisesti liikuntaohjelmalla. Poikkeava autonominen säätely ennustaa lyhyen aikavälin sydän- ja verisuonitautitapahtumia vain T2D:ta sairastavilla sepelvaltimotautipotilailla. Se ei kuitenkaan ole yhtä vahva itsenäinen ennustaja kuin tulehdusta kuvaava herkkä CRP.
336

Personal machine-to-machine (M2M) healthcare system with mobile device in global networks

Jung, S.-J. (Sang-Joong) 02 December 2013 (has links)
Abstract This thesis describes the development of a personal machine-to-machine (M2M) healthcare system that is both flexible and scalable. Based on the IPv6 protocol, the system can be used over a low-power wireless personal area network (6LoWPAN). Since a hierarchical network structure offers excellent accessibility, the system is applicable both to local and international healthcare services. To further enhance scalability and reliability, the proposed system combines 6LoWPAN with mobile techniques, depending on whether the sensor is located inside or outside the range of a wireless sensor network (WSN). Employing wearable low-power sensors, the system measures health parameters dynamically. For wireless transmission, these sensors are connected to an M2M node either through the internet or through an external IPv4/IPv6-enabled network. The applicability of the IEEE 802.15.4 and 6LoWPAN protocols to wide area networks were verified in practical tests using an M2M gateway. To assess the physical health of an individual, the system uses heart rate variability analysis in time and frequency domains. Acquired data are first stored on a server for analysis. Results of the analysis are then automatically sent to Android-based mobile devices carried by the individual or appointed healthcare providers. In this way, mobile techniques are used to support remote health monitoring services. This personal M2M healthcare system has the capacity to accurately process a large amount of biomedical signals. Moreover, due to its ability to use mobile technology, the system allows patients to conveniently monitor their own health status, regardless of location. / Tiivistelmä Tutkimuksessa kehitetään henkilökohtainen mobiililaitteden välillä toimiva (M2M) terveydenhoitojärjestelmä, joka mahdollistaa joustavan ja skaalautuvan potilaan terveyden monitoroinnin. Perustuen IPv6-protokollaan, sovellusta voidaan käyttää matalatehoisen langattoman 6LowPAN-verkon yli. Koska hierarkkinen verkkorakenne tarjoaa erinomaisen saavutettavuuden, järjestelmän kapasiteetti riittää paitsi kaupungin sisäisten myös kansainvälisten terveyspalvelujen järjestämiseen. Skaalattavuuden ja luotettavuuden vuoksi ehdotettu järjestelmä yhdistelee 6LowPAN-tekniikkaa mobiiliteknologiaan riippuen siitä onko sensori langattoman sensoriverkon kuuluvuusalueella vai sen ulkopuolella. Puettavia matalatehoisia sensoreita käyttävä järjestelmä kykenee mittaamaan terveysparametreja dynaamisesti. Langatonta siirtoa varten nämä sensorit on kytketty M2M-solmuun joko internetin tai ulkoisen IPv4/IPv6-verkon kautta. Käytännön testeissä IEEE802.15.4- ja 6LowPAN-protokollien soveltaminen laajaverkossa mahdollistettiin tähän soveltuvalla M2M-yhdyskäytävällä. Yksilöiden fyysisen terveyden arvioinnissa järjestelmä käyttää sydämen sykevaihtelun analysointia aika- ja taajuustasossa. Data tallennetaan palvelimelle analysointia varten. Analyysin tulokset lähetetään automaattisesti henkilöiden omiin tai heidän lääkäriensä mobiililaitteisiin. Näin mobiiliteknologiaa käytetään tukemaan terveyden etämonitorointipalveluja. Tämä henkilökohtainen M2M-kommunikointiin perustuva terveydenhoitojärjestelmä kykenee käsittelemään tarkkaan suuriakin määriä 6LowPAN-verkon ja internetin kautta tulevia biolääketieteellisiä signaaleja. Lisäksi kyky käyttää mobiiliteknologiaa tekee järjestelmästä potilaille miellyttävän tavan monitoroida omaa terveydentilaansa sijaintipaikasta riippumatta.
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Assessment of heart rate variability as an indicator of cardiovascular autonomic dysregulation in subjects with chronic epilepsy

Suorsa, E. (Eija) 01 November 2011 (has links)
Abstract Autonomic dysfunction in epilepsy is widely recognized. Both partial and generalized epilepsies affect autonomic functions during interictal, ictal and postictal states. Interestingly, there is increasing evidence of interictal autonomic nervous system dysfunction as evidenced by reduced heart rate (HR) variability in patients with epilepsy. Reduced HR variation has also been detected in many other chronic diseases and it has been shown to be associated with unfavourable prognosis with an increased risk of mortality in various heart diseases. Recently, more attention has also been paid to possible association of decreased HR variability with sudden unexpected death in epilepsy (SUDEP). However, the clinical significance of the observed changes in cardiovascular regulation in patients with epilepsy is still poorly outlined and there are no long-term studies about changes in HR variation in relation to epilepsy. This study was designed to evaluate long-term changes in autonomic cardiovascular regulation in patients with temporal lobe epilepsy (TLE) and also to evaluate HR variation during vagus nerve stimulation (VNS) treatment in patients with refractory epilepsy, using 24-hour ambulatory ECG recordings. Special attention was paid to changes in HR variation and to circadian HR fluctuation over time. The results of this study show that autonomic cardiovascular regulation is affected both in patients with well-controlled TLE and in patients with refractory TLE, and that the cardiovascular dysregulation also presents itself with changes in circadian HR variability, with more pronounced alterations observed during the night time. HR variability was also found to decrease progressively with time in patients with chronic refractory TLE with uncontrolled seizures. VNS treatment was not observed to alter HR variation. / Tiivistelmä Epilepsiapotilailla esiintyy autonomisen hermoston toiminnan häiriöitä. Näitä häiriöitä voidaan todeta epilepsiakohtausten aikana, heti kohtausten jälkeen ja kohtausten välillä sekä paikallisalkuisissa että yleistyneissä epilepsioissa. Viimeaikaisissa tutkimuksissa on osoitettu kardiovaskulaarisen säätelyjärjestelmän häiriöiden voivan ilmentyä alentuneena sydämen sykevaihteluna epilepsiakohtausten väliaikoina. Sydänsairauksien yhteydessä sykevaihtelun vähenemisen on osoitettu liittyvän kohonneeseen kuolemanriskiin. Epilepsiapotilailla alentuneen sydämen sykevaihtelun on epäilty liittyvän epilepsiapotilailla ilmenevien odottamattomien ja ilman selkeää syytä tapahtuvien äkkikuolemien (SUDEP) lisääntyneeseen riskiin. Kertyneestä tiedosta huolimatta alentuneen sykevaihtelun kliininen merkitys epilepsiapotilailla on edelleen epäselvä. Pitkäaikaisseurantatutkimuksia sydämen sykevaihtelun muutoksista epilepsiapotilailla ei ole julkaistu. Tämän tutkimuksen tarkoituksena oli selvittää ohimolohkoepilepsiaan liittyviä pitkäaikaisia interiktaalisia (kohtausten välillä esiintyviä) kardiovaskulaarisia ilmentymiä. Lisäksi haluttiin tutkia vaikeahoitoisessa epilepsiassa käytetyn hoitomuodon, vagushermostimulaation, mahdollisia vaikutuksia sydämen toimintaan. Erityisesti haluttiin analysoida sykevaihtelun vuorokausirytmiä. Tulokset osoittavat autonomisen hermoston kardiovaskulaarisen säätelyjärjestelmän toiminnan olevan häiriintyneen sekä vaikeahoitoisilla että hyvähoitoisilla ohimolohkoalkuista epilepsiaa sairastavilla potilailla. Sydämen sykevariaatio on alentunut erityisesti yöaikaan. Lisäksi sydämen sykevaihtelu alenee pitkäaikaisseurannassa vaikeahoitoista epilepsiaa sairastavilla potilailla, joilla ilmenee toistuvia epileptisiä kohtauksia. Vagusstimulaatio ei aiheuttanut muutoksia syketaajuuden vaihteluun.
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Modulação autonômica cardíaca na distrofia muscular de Duchenne durante tarefa no computador / Cardiac autonomic modulation in Duchenne muscular dystrophy during a computer task

Mayra Priscila Boscolo Alvarez 18 April 2016 (has links)
Introdução: A Distrofia Muscular de Duchenne (DMD) é caracterizada como uma fraqueza muscular progressiva que leva à incapacidade. Devido às dificuldades funcionais enfrentadas pelos indivíduos com DMD, o uso da tecnologia assistiva é essencial para proporcionar ou promover habilidades funcionais. Na DMD, além do comprometimento musculoesquelético, uma disfunção autonômica cardíaca também tem sido relatada. Assim, visamos investigar as respostas autonômicas agudas de indivíduos com DMD durante a realização de uma tarefa no computador. Método: A variabilidade da frequência cardíaca foi avaliada através de métodos lineares e não lineares, utilizando uma cinta torácica com equipamento de monitoramento de eletrocardiograma (ECG). Assim, 45 indivíduos foram incluídos no grupo com DMD e 45 no grupo de desenvolvimento típico (controle), avaliados for 20 minutos em repouso sentado e 5 minutos com a realização de uma tarefa no computador. Resultados: Os indivíduos com DMD apresentaram menor modulação cardíaca parassimpática durante o repouso, que diminuiu ainda mais durante a tarefa no computador. Conclusão: Indivíduos com DMD exibiram respostas autonômicas cardíacas mais intensas durante a tarefa no computador / Introduction: Duchenne muscular dystrophy (DMD) is characterized by progressive muscle weakness that leads to disability. Due to functional difficulties faced by individuals with DMD, the use of assistive technology is essential to provide or expand functional abilities. In DMD, as well as musculoskeletal impairment, cardiac autonomic dysfunction has also been reported. Thus, we aimed to investigate acute cardiac autonomic responses in a computer task of DMD subjects. Method: Heart rate variability was evaluated through linear and nonlinear methods, using a breast strap electrocardiogram (ECG) measuring device. Thus, 45 subjects were included in the group with DMD and 45 in the typical development (control) group, assessed for 20 minutes sitting at rest and five minutes with a task on the computer. Results: Individuals with DMD had lower parasympathetic cardiac modulation at rest, which decreased further during the task on the computer. Conclusion: Individuals with DMD exhibited more intense cardiac autonomic responses during computer tasks
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A influência da idade e da reposição hormonal sobre a modulação autonômica do coração e o limiar de anaerobiose. / Influence of age and hormonal replacement on the autonomic modulation of the heart and the anaerobisis threshold.

Valeria Ferreira Camargo Neves 13 March 2003 (has links)
Este trabalho teve por objetivo avaliar a modulação autonômica da freqüência cardíaca (FC) durante o repouso, nas posições supina e sentada, e durante teste de esforço físico dinâmico descontínuo do tipo degrau (TEFDD-D) em mulheres jovens e pós-menopausa sem (PMSRH) e com reposição hormonal (PMCRH); determinar o limiar de anaerobiose (LA) a partir da análise das respostas de FC e pela análise dos índices de RMSSD (raiz quadrada da média dos quadrados das diferenças entre os intervalos R-R normais sucessivos), em milissegundos (ms), e comparar o grau de correlação entre estas duas metodologias de análise. Foram estudadas 11 jovens (24 ± 2,77 anos), 13 PMSRH (57 ± 5,28) e 9 PMCRH (55 ± 5,40 anos). O TEFDD-D foi realizado em cicloergômetro, sendo iniciado com a potência de 15 W e com incrementos de 5 em 5 W. A FC (bpm) e os intervalos R-R (ms) foram captados em tempo real, por um período de 360s em repouso, em cada posição, e durante 60s em repouso sentado no cicloergômetro, 240s em exercício e 60s em recuperação, em cada potência do TEFDD-D. Foram calculados as médias da FC (bpm) e os índices de RMSSD dos intervalos R-R (ms) para as condições de repouso e durante 180s do exercício nas potências estudadas; cálculo da variação da FC (bpm) no início do exercício e do tempo (s) desta variação. A determinação do LA foi feita pelo ajuste do modelo matemático e estatístico semiparamétrico (SPM) aos dados de FC e pelos índices de RMSSD dos intervalos R-R (ms). Os testes estatísticos utilizados foram: Wilcoxon, Kruskall-Wallis, Friedman, Dunn e o teste de correlação de Spearman, nível de significância de 5%. Durante o repouso, as jovens apresentaram valores dos índices de RMSSD significativamente (p<0,05) superiores em relação aos outros 2 grupos. As variações da FC das jovens no início do exercício foram maiores que as dos grupos PMSRH e PMCRH, enquanto que o tempo de variação da FC foi similar entre os 3 grupos. Na transição do repouso para o exercício, a FC aumentou progressivamente, enquanto que a variabilidade da freqüência cardíaca (VFC) diminuiu. Na comparação intergrupo dos índices de RMSSD, obtidos em cada nível de potência, foi observada diferença significativa (p<0,05) apenas em 35W. Tanto pelo modelo SPM, como pela análise dos índices de RMSSD, as jovens atingiram o LA em potências superiores comparativamente as PMSRH e PMCRH. Os grupos PMSRH e PMCRH apresentaram resultados similares. Não foram observadas diferenças significativas (p>0,05) na comparação dos 2 métodos. O teste de correlação de Spearman mostrou uma associação significativa (p<0,05) entre os mesmos. Estes dados sugerem que após a menopausa ocorre uma diminuição da modulação vagal sobre o coração tanto em repouso como durante o exercício físico, decorrente do processo do envelhecimento e da redução da capacidade física. A terapia de reposição hormonal não teve nenhuma influência sobre os resultados. As duas metodologias de análise do LA se mostraram similares, sugerindo que a mudança de inclinação da resposta da FC ocorre em níveis de esforço em que a VFC se encontra significativamente reduzida. / The objectives of the present study were to assess the autonomic modulation of the heart rate (HR) at rest, in the supine and sitting position, and during a step type discontinuous dynamic physical effort (STDDPE) in young and postmenopausal women not receiving (PMWtHR) and receiving hormonal replacement treatment (PMWHR); to determine the anaerobiosis threshold (AT) based on the analysis of HR response and the RMSSD indices (square root of the mean squared differences of successive R-R intervals), in milliseconds (ms), and to compare the degree of correlation between these two analysis methodologies. The study was conducted on 11 young women (24 ± 2.77 years), 13 PMWtHR (57 ± 5.28) and 9 PMWHR (55 ± 5.40 years). The STDDPE was performed on a bicycle ergometer at an initial power of 15 W, followed by power increments of 5 W. HR (bpm) and R-R intervals (ms) were obtained in real time over a period of 360 s under resting conditions in each position, during 60 s in the sitting rest position on the bicycle ergometer, 240 s during exercise and 60 s during recuperation at each STDDPE power. Mean HR (bpm) and RMSSD indices of the R-R intervals (ms) were calculated for the resting condition and during 180 s of exercise in the powers studied; the HR variation (bpm) and its time (s) were also calculated in the beginning of exercise. AT was determined by the semiparametric mathematical and statistical model (PMS) and by the RMSSD indices of the R-R intervals (ms). Data were analyzed statistically by the Wilcoxon, Kruskal-Wallis, Friedman, Dunn and Spearman correlation tests, with the level of significance set at 5%. During rest, young women presented significantly higher RMSSD indices (p<0.05) than the other 2 groups. The HR variations in young women in the beginning of the exercise were higher than the ones from the PMWtHR and PMWHR groups, whereas HR variations time was similar for the 3 groups. During the transition from rest to exercise HR increased progressively and HRV decreased. Intergroup comparison of RMSSD indices, obtained in each level of power, showed a significant difference (p<0.05) only at 35 W power. On both PMS model and RMSSD indices analysis, young women reached AT at a higher power compared to PMWtHR and PMWHR groups. The PMWtHR and PMWHR groups presented similar results. No significant differences (p>0.05) were observed when the methods were compared. The Spearman correlation test showed a significant association (p<0.05) between methods. These data suggest that after menopause there is a decrease in vagal modulation of the heart both at rest and during physical exercise due to the aging process and the reduction in physical capacity. Hormonal replacement therapy had no effect on the results. Both methodologies of AT analysis were similar, suggesting that the change in the HR response occurs in levels of effort in which the HRV is significantly reduced.
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Avaliação da modulação simpática e vagal, da pressão arterial e do perfil metabólico de mulheres jovens usuárias e não usuárias de contraceptivo hormonal oral combinado / Evaluation of sympathetic and vagal modulation, blood pressure and metabolic profile of young women, users and non-users of combined oral hormonal contraceptive

Morais, Tércio Lemos de 21 February 2014 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2015-07-27T13:13:00Z No. of bitstreams: 1 Tercio Lemos de Morais.pdf: 1272228 bytes, checksum: ed3fb7d1f441b1f6ede36571fcb2cb7a (MD5) / Made available in DSpace on 2015-07-27T13:13:00Z (GMT). No. of bitstreams: 1 Tercio Lemos de Morais.pdf: 1272228 bytes, checksum: ed3fb7d1f441b1f6ede36571fcb2cb7a (MD5) Previous issue date: 2014-02-21 / Evidence suggests the association of combined oral contraceptives (COC) with the development of hypertension, metabolic dysfunction and cardiovascular risk. The mechanisms involved in such association are not fully understood. It was demonstrated in previous studies by our group that there is an autonomic modulation imbalance before the development of hypertension in people with a positive family history of hypertension. This project evaluates the impact of combined oral contraceptives on anthropometric (BMI, abdominal circumference), hemodynamic (blood pressure, heart rate, cardiac outflow and total peripheral resistance), metabolic (serum glucose, total cholesterol and triglycerides) and autonomic (serum cathecolamines, heart rate variability) in normotensive and in hypertensive women (18 to 35 years of age) under combined oral contraceptives. We did not observe any significant change in blood pressure, hemodynamic and autonomic variables in the normotensive group under second and third generation of combined oral contraceptives. The same with hypertensive women under drospirenona (DRSP) and etinilestradiol (EE). Concerning the metabolic variables (against the control group), the normotensive women under combined oral contraceptives showed an increase in both means of total cholesterol (165.95 ± 29.21 vs 189.11 ± 28.96) and triglycerides (72.62 ± 23.44 vs 110.07 ± 40.60). Hypertensive women under DRSP+EE had also a significant increase in triglycerides when comparing basal (72.62 ± 23.44 vs 110.07 ± 40.60) with the later 6 month period( 72.62 ± 23.44 vs 110.07 ± 40.60). Moreover, in this same group of hypertensive women under Drospirenone-containing oral contraceptive, no change was found in potassium levels, the aldosterone-renin-angiotensin system or pharmacological interactions with anti-hypertensive drugs. Our conclusion is that second and third generation combined hormonal oral contraceptives causes no significant change in blood pressure or hemodynamic and autonomic variables. Also, DRSP+EE demonstrates a safe profile when used by young hypertensive women under anti-hypertensive drugs. No detectable variations in blood pressure and neuro-humoral activation, no hydro electrolyte imbalance and no metabolic change (except for a slight triglycerides augmentation) was encountered. / Existem evidências da associação entre uso de contraceptivo hormonal oral combinado (CHOC) com o desenvolvimento de hipertensão arterial, distúrbios metabólicos e risco cardiovascular. Os mecanismos envolvidos ainda não estão totalmente elucidados. Estudos prévios do nosso grupo demonstraram que há um desequilíbrio na modulação autonômica, mensurada pela análise da variabilidade da frequência cardíaca, antecedendo o desenvolvimento de HAS em filhos de hipertensos. No presente projeto, avaliamos o impacto do uso de CHOC em parâmetros antropométricos (índice de massa corpórea, circunferncia abdominal), hemodinâmicos (pressão arterial, frequencia cardíaca, débito cardíaco e resistência vascular periférica), metabólicos (glicemia, colesterol total e triglicérides), e autonômicos (dosagem sérica de noradrenalina e variabilidade da frequência cardíaca) em mulheres normotensas e hipertensas usuárias e não usuárias de CHOC, na faixa etária de 18 a 35 anos de idade. Como resultados, não observamos mudanças significativas na pressão arterial, variáveis hemodinâmicas e autonômicas na coorte de mulheres normotensas usuárias e não usuárias de CHOC de segunda e terceira geração, bem como no estudo prospectivo de mulheres hipertensas usuárias de drospirenona (DRSP) mais etinilestradiol (EE). Com relação às variáveis metabólicas, comparado ao grupo controle, a coorte de mulheres normotensas usuárias de CHOC apresentou valores médios de colesterol total (165,95 ± 29,21 vs 189,11 ± 28,96) e triglicérides (72,62 ± 23,44 vs 110,07 ± 40,60) superiores aos observados no grupo das não usuárias. As mulheres hipertensas usuárias de DRSP+EE, também apresentaram valores médios de triglicérides superiores estatisticamente significantes comparado ao momento inicial (124,3 ± 57,7 vs 174,7 ± 70,6), respectivamente basal e após 6 meses. Ainda no grupo de hipertensas, o uso de CHOC contendo drospirenona não se associou a mudanças na atividade do sistema renina angiotensina aldosterona, não alterou os níveis séricos de potássio, nem apresentou interações medicamentosas com medicamentos anti-hipertensivos usados. Concluímos que o uso de CHOC de segunda e terceira geração não causou alterações significativas na pressão arterial, parâmetros hemodinâmicos e autonômicos, com modesto impacto negativo sobre o perfil lipídico. E a DRSP+EE apresenta um perfil seguro quando usado como contraceptivo num grupo de mulheres hipertensas jovens já em uso de anti-hipertensivos, considerando-se que: não foram detectadas variações nos valores de pressão aretrial e de ativação neuro-humoral, não ocorreram distúrbios hidro eletrolíticos, e nem alterações em parâmetros metabólicos, execeto um leve aumento nos níveis de triglicérides.

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