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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.
641

Influence of age, hypertension or myocardial infarction on cardiovascular responses to changes in body position : a population-based study in 30-, 50- and 60-year-old men

Hofsten, Anna January 2000 (has links)
An age-related attenuation of the normal increase in diastolic blood pressure and heart rate upon standing has previously been observed in man. Whether this is due to aging as such or is a consequence of a higher prevalence of cardiovascular disease in older compared to younger subjects is unclear. This population-based study addresses this question and presents the blood pressure and heart rate responses to sudden changes in body position in representative groups of men aged 30 (n=50), 50 (n=44) and 60 (n=69) years, as well as in 60-year-old men with hypertension (n=75) or previous myocardial infarction (n=39) and in a control group (n=41) free from these diseases. Blood pressure and heart rate were measured during three seven-minute periods (supinestanding-supine), using an unbiased non-invasive method. Whereas there was an initial decrease in systolic blood pressure upon standing in men aged 50 and 60 years, an increase was seen in the 30-year-olds. The diastolic blood pressure increased in all age groups, but less in the older compared to the younger men. In all age groups, the change in systolic blood pressure upon standing was transient, while the changes in the diastolic blood pressure lasted during the entire observation period. The heart rate increased to a similar extent upon standing in all age groups. After resuming the supine position, both blood pressure and heart rate returned to the levels initially recorded. The cardiovascular responses were both qualitatively and quantitatively similar in all three groups of 60-year-old men (with or without hypertension or previous myocardial infarction). In conclusion, this population-based study confirmed previous observations of an age-related attenuation of the blood pressure response to change in body position. However, 60-year-old men with hypertension or previous myocardial infarction had blood pressure responses similar to those of men of the same age and free from these diseases. This indicates that the attenuated response in older compared to younger subjects is not explained by the higher prevalence of these cardiovascular diseases in the elderly, but appears to be the result of normal aging.
642

Associação entre síndrome das apnéias-hipopnéias do sono e variabilidade da pressão arterial

Steinhorst, Ana Maria Pasquali January 2013 (has links)
Introdução: O desenvolvimento de hipertensão arterial e doença cardiovascular relacionado à síndrome das apnéia obstrutiva do sono (SAOS) parece estar relacionado a alterações sobre a regulação autonômica cardiovascular. Este estudo investigou se a SAOS influência a variabilidade da pressão arterial (PA). Métodos: Estudo transversal, com pacientes hipertensos que foram submetidos à polissonografia nível III, por meio de um monitor portátil de uso domiciliar para detectar SAOS (índice de apnéia-hipopnéia (IAH) ≥ 10). A variabilidade da PA foi avaliada pela taxa de variação da pressão arterial no tempo (índice “time rate” - a primeira derivada da pressão arterial ao longo do tempo) e desvio padrão (DP) da PA obtidos dos dados da monitorização ambulatorial da pressão arterial (MAPA). Análises univariadas e multivariadas foram utilizadas para testar a associação entre a SAOS, IAH e variabilidade da pressão arterial. Resultados: Os pacientes com SAOS (n = 57) eram mais velhos, apresentavam pressão arterial mais elevada e maior duração da hipertensão do que pacientes sem SAOS (n = 50). Não houve nenhuma associação consistente entre o diagnóstico de SAOS e variabilidade da PA aferida pelo DP e pela taxa de variação da PA no tempo, tanto na análise univariada como após o ajuste para idade, IMC e respectiva medida de PA na MAPA. Não houve correlação significativa entre o AIH e os índices de variabilidade da PA em um modelo de regressão linear múltipla, controlando para idade, IMC e PA correspondente. Conclusão: SAOS não influencou a variabilidade da pressão arterial, aferida por estes métodos, em pacientes com hipertensão. / Background The risk of obstructive sleep apnea syndrome (OSAS) for the development of hypertension and cardiovascular disease may be intermediate by influence over autonomic cardiovascular regulation. This study investigated if OSAS influences blood pressure (BP) variability. Methods In a cross-sectional study, patients with hypertension underwent level III polysomnography by means of a home portable monitor to detect OSAS, (apnea-hypopnea index (AHI) ≥10). BP variability was assessed by the time rate index (the first derivative of BP over time) and standard deviation (SD) of BP measured by 24-h ambulatory blood pressure measurement (ABPM). The association between OSAS, AHI and blood pressure variability was tested by univariate and multivariate methods. Results: Patients with OSAS (n = 57) were older, had higher blood pressure, and longer duration of hypertension than patients without OSAS (n = 50). There was no consistent association between the diagnosis of OSAS and BP variability assessed by the time-rate index and SD both in the univariate and after adjustment for age, BMI and the respective BP. There was no significant correlation between AIH and the indexes of BP variability in a multiple linear regression model controlling for age, BMI and the corresponding BP. Conclusion OSAS does not influence blood pressure variability in patients with hypertension.
643

Effect of vegetarian diets on the presentation of metabolic syndrome or its components: a systematic review and meta-analysis

Picasso, Maria C., Lo-Tayraco, Jessica A., Ramos-Villanueva, Juselly M., Pasupuleti, Vinay, Hernandez, Adrian V. January 2018 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Background & aims: Several studies have examined the effect of vegetarian diets (VD) on metabolic syndrome (MetS) or its components, but findings have been inconsistent. The aim of this study was to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies to assess the association between VD and MetS or its components (systolic blood pressure [SBP], diastolic blood pressure [DBP], fasting glucose triglycerides, waist circumference [WC], HDL-cholesterol (HDL-C)) in adults. Methods: The Cochrane Library, EMBASE, PubMed, Web of Science, and Scopus were searched. RCTs, cohort studies and cross-sectional studies evaluating the effects of VD on MetS or its components in adults, with omnivore diet as control group, were included. Random effects meta-analyses stratified by study design were employed to calculate pooled estimates. Results: A total of 71 studies (n = 103 008) met the inclusion criteria (6 RCTs, 2 cohorts, 63 cross-sectional). VD were not associated with MetS in comparison to omnivorous diet (OR 0.96, 95% CI 0.50–1.85, p = 0.9) according to meta-analysis of five cross-sectional studies. Likewise, meta-analysis of RCTs and cohort studies indicated that consumption of VD were not associated with MetS components. Meta-analysis of cross-sectional studies demonstrated that VD were significantly associated with lower levels of SBP (mean difference [MD] −4.18 mmHg, 95%CI −5.57 to −2.80, p < 0.00001), DBP (MD −3.03 mmHg, 95% CI −4.93 to −1.13, p = 0.002), fasting glucose (MD −0.26 mmol/L, 95% CI −0.35to −0.17, p < 0.00001), WC (MD −1.63 cm, 95% CI −3.13 to −0.13, p = 0.03), and HDL-C (MD −0.05 mmol/L, 95% CI −0.07 to −0.03, p < 0.0001) in comparison to omnivorous diet. Heterogeneity of effects among cross-sectional studies was high. About, one-half of the included studies had high risk of bias. Conclusions: VD in comparison with omnivorous diet is not associated with a lower risk of MetS based on results of meta-analysis of cross-sectional studies. The association between VD and lower levels of SBP, DBP, HDL-C, and fasting glucose is uncertain due to high heterogeneity across the cross-sectional studies. Larger and controlled studies are needed to evaluate the association between VD and MetS and its components. / Revisión por pares
644

Advances in point process filters and their application to sympathetic neural activity

Zaydens, Yevgeniy 12 March 2016 (has links)
This thesis is concerned with the development of techniques for analyzing the sequences of stereotypical electrical impulses within neurons known as spikes. Sequences of spikes, also called spike trains, transmit neural information; decoding them often provides details about the physiological processes generating the neural activity. Here, the statistical theory of event arrivals, called point processes, is applied to human muscle sympathetic spike trains, a peripheral nerve signal responsible for cardiovascular regulation. A novel technique that uses observed spike trains to dynamically derive information about the physiological processes generating them is also introduced. Despite the emerging usage of individual spikes in the analysis of human muscle sympathetic nerve activity, the majority of studies in this field remain focused on bursts of activity at or below cardiac rhythm frequencies. Point process theory applied to multi-neuron spike trains captured both fast and slow spiking rhythms. First, analysis of high-frequency spiking patterns within cardiac cycles was performed and, surprisingly, revealed fibers with no cardiac rhythmicity. Modeling spikes as a function of average firing rates showed that individual nerves contribute substantially to the differences in the sympathetic stressor response across experimental conditions. Subsequent investigation of low-frequency spiking identified two physiologically relevant frequency bands, and modeling spike trains as a function of hemodynamic variables uncovered complex associations between spiking activity and biophysical covariates at these two frequencies. For example, exercise-induced neural activation enhances the relationship of spikes to respiration but does not affect the extremely precise alignment of spikes to diastolic blood pressure. Additionally, a novel method of utilizing point process observations to estimate an internal state process with partially linear dynamics was introduced. Separation of the linear components of the process model and reduction of the sampled space dimensionality improved the computational efficiency of the estimator. The method was tested on an established biophysical model by concurrently computing the dynamic electrical currents of a simulated neuron and estimating its conductance properties. Computational load reduction, improved accuracy, and applicability outside neuroscience establish the new technique as a valuable tool for decoding large dynamical systems with linear substructure and point process observations.
645

Association of Apolipoprotein E (Apo E) polymorphism with the prevalence of metabolic syndrome (MetS): the National Heart, Lung and Blood Institute Family Heart Study

Lai, Lana Yin Hui January 2013 (has links)
BACKGROUND & AIMS - Metabolic syndrome (MetS), characterized by abdominal obesity, atherogenic dyslipidemia, elevated blood pressure, and insulin resistance is a major public health concern in the United States. The effect of Apolipoprotein E (Apo E) polymorphism has been relatively well studied in relation to cardiovascular disease; however, its effects on MetS are not well established. METHODS - We conducted a cross-sectional study consisting of 1,551 participants from the National Heart, Lung, and Blood Institute (NHLBI) Family Heart Study to assess the relation of Apo E polymorphism with the prevalence of MetS. Information on the different Apo E genotypes was extracted from the database and we defined MetS according to the AHA-NHLBI-IDF-WHO Harmonized Criteria. We used generalized estimating equations to estimate adjusted odds ratios for prevalent MetS and the Bonferroni correction to account for multiple testing in the secondary analysis. RESULTS – Our study population had a mean age (SD) of 56.5 (11.0) years and 49.7% had MetS. There was no association between the Apo E genotypes and MetS. The multivariable adjusted ORs (95% CI) were 1.00 (reference), 1.26 (0.31-5.21), 0.89 (0.62- 1.29), 1.13 (0.61-2.10), 1.13 (0.88-1.47) and 1.87 (0.91-3.85) for the *e3/e3, *e2/e2, *e2/e3, *e2/e4, *e3/e4 and *e4/e4 genotype respectively. In a secondary analysis, the *e2/e3 genotype was associated with lower HDL levels, with the multivariable adjusted ORs (95% CI) of 0.59 (0.36-0.95) when compared to the reference *e3/e3 genotype. CONCLUSIONS - Our findings do not support an association between Apo E polymorphism and MetS in a multi-center population based study of predominantly white US men and women. The *e2/e3 genotype was associated with lower HDL levels as compared to the *e3/e3 genotype. KEY WORDS: Apolipoprotein E (Apo E) polymorphism, metabolic syndrome, blood pressure, glucose, waist circumference, triglycerides, high-density lipoprotein cholesterol
646

Cardiovascular responses to cold exposure in untreated hypertension

Hintsala, H. (Heidi) 13 August 2018 (has links)
Abstract Cold weather associates with higher cardiovascular morbidity and mortality in various climates. It is also known that exposure to a cold environment instantly activates sympathetic nervous system and elevates blood pressure (BP) in healthy individuals. Hypertension can increase sympathetic reactivity and arterial stiffness, and could therefore exaggerate these cold-related changes. We implemented an experimental study to assess cardiovascular responses to habitual type of cold exposure among subjects with untreated hypertension. We selected a random sample of middle-aged men in the city of Oulu, Finland. The recruitment included home BP measurements. 51 untreated hypertensive men and 32 men without hypertension (controls) underwent 15 minutes whole-body cold exposure (temperature -10&#176;C, wind speed 3m/s, winter clothing, standing). Brachial, central aortic, and continuous BP, as well as electrocardiography (ECG) were measured before (15 min), during (15 min), and after (20 min) the exposure. Skin temperature and thermal sensations were also assessed. The employed exposure increased central and brachial systolic (ca. 25 mmHg) and diastolic (ca. 10 mmHg) BP in both test groups. One fourth of men with mild to moderate hypertension had systolic BP exceeding 200 mmHg while exposed to cold. Small heart rate (HR) reduction was not enough to compensate for the elevated BP, and cardiac workload increased during cold exposure. Cardiac repolarization showed modest arrhythmogenic changes and frequency of ventricular ectopic beats increased slightly in cold conditions. Cold exposure also increased cardiac vagal baroreflex sensitivity in both test groups, whereas an estimate of vascular sympathetic activity increased only among controls. We also found an elevated systolic home BP variability to associate with higher cardiac workload and BP responses to cold. Moderate cold air exposure substantially increased BP but also activated cardiac vagal regulation among untreated hypertensive and non-hypertensive men. The BP level reached in cold conditions was considerably high in those with hypertension, and especially in those with both hypertension and higher home BP variability. These results are important to health care professionals who treat hypertensive patients. The importance of year-round BP control and proper protection from cold should not be underestimated. / Tiivistelmä Kylmään säähän liittyvä verenkiertoelimistön sairauksien paheneminen on havaittu eri ilmastoissa. Tiedetään myös, että terveillä henkilöillä sympaattisen hermoston aktiivisuus ja verenpaine nousevat kylmässä ympäristössä. Kohonnut verenpaine eli hypertensio voi lisätä sympaattista reaktiivisuutta ja valtimojäykkyyttä sekä siten voimistaa verenkiertoelimistön kylmävasteita. Kokeellinen tutkimuksemme arvioi sydämen ja verisuoniston vasteita tavanomaiseen kylmäaltistukseen hoitamatonta hypertensiota sairastavilla henkilöillä. Tutkittavat olivat Oulun väestöstä satunnaisesti valittuja keski-ikäisiä miehiä, joilta määritettiin verenpaine kotimittauksilla. 51 hoitamatonta hypertensionta sairastavaa miestä ja 32 miestä, joilla ei ollut hypertensiota (verrokit), altistettiin 15 minuutin ajan kylmälle (lämpötila -10 &#176;C, tuuli 3 m/s, talvivaatteet, seisten). Verenpainetta mitattiin olkavarresta, epäsuorasti sydämestä ja jatkuvana signaalina ennen altistusta (15 min), sen aikana (15 min) ja jälkeen (20 min). Samalla seurattiin sydämen sähköistä toimintaa, iholämpötiloja ja lämpötuntemuksia. Kylmäaltistus kohotti sekä sydämen että olkavarren ylä- (noin 25 mmHg) ja alapainetta (noin 10 mmHg) molemmissa tutkimusryhmissä. Neljäsosalla lievää tai kohtalaista hypertensiota sairastavista miehistä yläpaine kohosi yli 200 mmHg tasolle. Sykkeen lasku ei riittänyt tasapainottamaan kohonnutta verenpainetta ja sydämen työmäärä nousi. Sydämen rytmihäiriöherkkyys ja vastaavasti kammiolisälyöntien esiintymistiheys olivat myös hieman koholla altistuksen aikana. Kylmäaltistus kasvatti sydämen vagaalista barorefleksiherkkyyttä molemmissa ryhmissä. Verisuonten sympaattinen verenpainevaihtelu kasvoi vain verrokeilla. Sydämen työmäärä ja verenpaine kohosivat kylmässä enemmän heillä, joiden verenpaineen vaihtelu kotona oli korkeampi. Tavanomaista talvipäivää vastaava kylmäaltistus kohotti verenpainetta voimakkaasti, mutta myös aktivoi sydämen suojaavaa säätelyä sekä hoitamatonta hypertensiota sairastavilla että verrokeilla. Kylmässä saavutettu verenpainetaso oli merkittävä heillä, joilla oli hypertensio, ja erityisesti heillä, joilla oli sekä hypertensio että suurempi kotiverenpainevaihtelu. Tämä tutkimustieto on tärkeää hypertensiopotilaille sekä heitä hoitaville terveydenhuollon ammattilaisille. Tulokset korostavat ympärivuotisen verenpainekontrollin ja kylmältä suojautumisen tärkeyttä.
647

Exercícios de respiração do ioga aplicados a pacientes hipertensos sob tratamento em unidade básica de saúde / Yoga breathing exercises applied to hypertensive patients undergoing treatment in public primary healthcare units

Brandani, Jeniffer Zanetti 15 June 2018 (has links)
Submitted by JENIFFER ZANETTI BRANDANI (jeniffer_brandani@yahoo.com.br) on 2018-08-14T17:18:25Z No. of bitstreams: 1 Dissertação BRANDANI, JZ - pós defesa.pdf: 1246287 bytes, checksum: d40daa507b421c11f4b8f51974ebe3d7 (MD5) / Rejected by Minervina Teixeira Lopes null (vina_lopes@bauru.unesp.br), reason: Favor realizar nova submissão inserindo Ata de Defesa. Agradecemos a compreensão. on 2018-08-14T17:31:03Z (GMT) / Submitted by JENIFFER ZANETTI BRANDANI (jeniffer_brandani@yahoo.com.br) on 2018-08-14T17:45:27Z No. of bitstreams: 1 Dissertação BRANDANI, JZ - pós defesa.pdf: 2736988 bytes, checksum: 982d6f9b350ab809c61d6dfe06216e07 (MD5) / Approved for entry into archive by Minervina Teixeira Lopes null (vina_lopes@bauru.unesp.br) on 2018-08-15T13:19:35Z (GMT) No. of bitstreams: 1 brandani_jz_me_bauru.pdf: 2655449 bytes, checksum: 24c4ddd8276886ec98edee641eb34c0a (MD5) / Made available in DSpace on 2018-08-15T13:19:35Z (GMT). No. of bitstreams: 1 brandani_jz_me_bauru.pdf: 2655449 bytes, checksum: 24c4ddd8276886ec98edee641eb34c0a (MD5) Previous issue date: 2018-06-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Introdução: O número de indivíduos acometidos pela hipertensão arterial é alarmante em todo o mundo, por isso, a busca por estratégias eficazes para a redução dos valores de pressão arterial e suas consequências, são objetos de inúmeros estudos. As práticas de ioga vêm sendo incentivadas por meio da Política Nacional de Práticas Integrativas e Complementares no SUS, por se mostrar eficaz na prevenção e tratamento de diversas patologias, entre elas a hipertensão arterial, apresentando efeito hipotensor significativo. Podendo ser utilizado com todas as técnicas (princípios éticos, asanas, pranayamas, relaxamento, meditação) em conjunto em uma mesma sessão ou de forma isolada, como muitos estudos investigando apenas relaxamentos e/ou pranayamas. Objetivos: a) Levantar os estudos que abordam os efeitos dos exercícios de controle respiratório (pranayamas) sobre a pressão arterial; b) Verificar o efeito de intervenção com pranayamas com ritmo lento na pressão arterial de hipertensos, sob tratamento em Unidade Básica de Saúde (UBS). Métodos: Para isso, foram conduzidos dois estudos principais. a) Uma revisão sistemática de ensaios clínicos que buscaram verificar os efeitos dos pranayamas na pressão arterial. Foram pesquisadas três bases de dados eletrônicas PubMed/Medline, Scopus e Bireme, a análise de viés foi avaliada pela escala PEDro. b) Um ensaio clínico randomizado e controlado, composto por dois grupos (ioga - GI e exercício controle ativo - GCA). O programa foi composto de 16 sessões com duração de 30 minutos e as análises foram compostas por medidas de pressão arterial ao início e fim do programa. Resultados: a) Todos os estudos em que os participantes eram hipertensos apresentaram redução na pressão arterial sistólica (PAS) tanto nos estudos que avaliaram efeito agudo quanto nos que avaliaram o efeito crônico; na pressão arterial diastólica (PAD) apenas três estudos demonstraram redução significativa (dois investigando efeito crônico); já a frequência cardíaca apresentou diminuição em sete estudos (4 investigando efeito agudo). b) Os grupos apresentaram redução significativa na PAS nos momentos, porém não foi encontrada diferença entre os grupos; os pacientes eram em sua maioria mulheres, brancos, com IMC acima do valor recomendado e classe econômica B e C; apresentavam níveis de atividade física dentro das recomendações (>150min/semana). Conclusão: a) A revisão sistemática forneceu indícios de que a utilização de pranayamas lentos e/ou com narinas alternadas possa ser uma alternativa efetiva para reduzir a pressão arterial em pacientes normotensos e hipertensos. Porém, o alto número de viés nos estudos iseridos limitam estes resultados. Portanto, são necessários novos estudos com maior rigor metodológico na área de ioga, para que os benefícios desta prática seja fortalecido e ganhe espaço como complemento ao tratamento farmacológico. b) O ensaio clínico indicou que 16 sessões de pranayamas apresentam efeito hipotensor crônico para PAS em pacientes com hipertensão arterial, mas não foram encontradas diferenças entre o GI e GCA. Porém, o baixo número de pacientes incluídos, limita as análises e as possíveis respostas da pressão arterial aos pranayamas. / Introduction: The number of individuals affected by arterial hypertension is alarming worldwide, so the search for effective strategies to reduce blood pressure values and their consequences are the subject of numerous studies. The practices of yoga have been encouraged through the National Politics of Integrative and Complementary Practices in the SUS, for being effective in the prevention and treatment of several pathologies, including arterial hypertension, with a significant hypotensive effect. It can be used with all techniques (ethical principles, asanas, pranayamas, relaxation, meditation) together in the same session or in isolation, as many studies investigating only relaxation and / or pranayamas. Objectives: a) Raise studies that address the effects of respiratory control exercises (pranayamas) on blood pressure; b) To verify the effect of intervention with pranayamas with slow rhythm in the hypertensive blood pressure, under treatment in Basic Health Unit (UBS). Methods: Two main studies were conducted. a) A systematic review of clinical trials that sought to verify the effects of pranayamas on blood pressure. We searched three electronic databases PubMed / Medline, Scopus and Bireme, the bias analysis was evaluated by the PEDro scale. b) A randomized controlled trial, composed of two groups (yoga - GI and exercise control active - GCA). The program consisted of 16 sessions lasting 30 minutes and the analyzes were composed of blood pressure measurements at the beginning and end of the program. Results: a) All studies in which the participants were hypertensive had a reduction in systolic blood pressure (SBP), both in the studies that evaluated the acute effect and in those that evaluated the chronic effect; in diastolic blood pressure (DBP) only three studies showed significant reduction (two investigating chronic effect); already the heart rate presented decrease in seven studies (4 investigating acute effect). b) Groups showed a significant reduction in SBP at moments, but no difference was found between groups; the patients were mostly white women with BMI above the recommended value and economic class B and C; presented levels of physical activity within the recommendations (> 150min / week). Conclusion: a) The systematic review has provided indications that the use of slow pranayamas and / or alternate nostrils may be an effective alternative for reducing blood pressure in normotensive and hypertensive patients. However, the high number of bias in the iserid studies limits these results. Therefore, new studies with greater methodological rigor in the area of yoga are needed, so that the benefits of this practice are strengthened and gain space as a complement to pharmacological treatment. b) The clinical trial indicated that 16 sessions of pranayamas present a chronic hypotensive effect for SBP in patients with arterial hypertension, but no differences were found between GI and GCA. However, the low number of patients included limits the analyzes and possible responses of blood pressure to pranayamas.
648

Incidência de hipertensão arterial pelo consumo de álcool : é modificável pela raça? / Incidence of hypertension by alcohol consumption: is it Modifiable by race?

Steffens, André Avelino January 2005 (has links)
A associação entre consumo de bebidas alcoólicas e a incidência de hipertensão pode ser dependente do padrão de consumo e raça. Em um estudo de coorte de base populacional, foram entrevistados no domicílio 1089 adultos, selecionados ao acaso. A pressão arterial e medidas antropométricas foram aferidas de acordo com recomendações padronizadas. A quantidade de álcool consumida foi avaliada por um questionário de quantidade-freqüência. Binge drinking foi definido pelo consumo de 5 ou mais drinques em uma ocasião para homens ou 4 drinques para mulheres, e abuso de álcool, por consumo de 30 ou mais gramas por dia em homens ou 15 g ou mais em mulheres. Os entrevistadores classificaram a cor da pele dos participantes em brancos e não-brancos. Casos incidentes de hipertensão foram caracterizados por PA ≥ 140/90 mmHg ou uso de medicamento anti-hipertensivo. A razão de risco (RR) para incidência de hipertensão arterial foi computada em modelo de Cox. Entre os 589 indivíduos normotensos na entrevista basal, foram identificados 127 casos incidentes de hipertensão, após um seguimento de 5,6 ± 1,1 anos. Não houve associação de binge drinking e dependência de álcool (CAGE) com a incidência de hipertensão. A RR ajustada (idade, educação) para a incidência de hipertensão (IC 95% ) foi significativa apenas para indivíduos não-brancos que consumiam 30 g ou mais de etanol por dia: 7,3 (1,4 - 39,3). A pressão arterial sistólica aumentou entre os abusadores não brancos 16,1 ± 3,5 mmHg, em comparação com 4,9 ± 1,5 mmHg entre os abusadores brancos (P= 0,004). Indivíduos com ancestrais africanos que consumisam grandes quantidades de álcool apresentaram maior risco de desenvolverem hipertensão arterial. Este risco não foi explicado por binge drinking ou dependência de álcool. / The association between alcoholic beverage consumption and incidence of hypertension may be dependent of the pattern of consumption and race. In a population-based cohort study, 1089 adults, interviewed at home, had BP and anthropometric measurements carried out according to standardized recommendations. Alcohol consumption was ascertained by an amount-frequency questionnaire. Binge drinking was defined by consumption of 5 or more drinks in one occasion for male or 4 drinks for women, and abuse of alcohol by consumption of 30 or more grams per day in men or 15 g or more in women. Interviewers classified the skin color of participants in white and non-white. Incident cases of hypertension were characterized by BP ≥ 140/90 mmHg or use of hypertension medication. Hazard ratios (HR) were computed in a Cox model. Among 589 normotensive individuals in the baseline visit, 127 incident cases of hypertension were identified, after a follow up of 5.6 ± 1.1 years. Binge drinking and alcohol dependency (CAGE) were not associated with the incidence of hypertension. Adjusted (age, education) HR for the incidence of hypertension (95% CI) was significant only for non-white individuals who consumed 30 g or more of ethanol per day: 7.3 (1.4 to 39.3). Systolic blood pressure of black abusers increased 16.1 ± 3.5, in comparison with 4.9 ± 1.5 mmHg among white abusers (P = 0.004). Individuals with an African ancestry, who consumed larger amounts of ethanol, were at higher risk of developing hypertension. This risk was not explained by binge drinking or addiction to alcohol.
649

Associação entre pressão arterial ambulatorial e variáveis antropométricas em pré-adolescentes e adolescentes

Pereira, Fabiano Amorim January 2006 (has links)
Observou-se a prevalência crescente das doenças cardiovasculares nos dias de hoje e o acometimento cada vez maior da população pediátrica. O objetivo principal no presente estudo foi verificar a associação entre a pressão arterial ambulatorial e variáveis antropométricas em 34 pré-adolescentes e adolescentes na faixa de idade entre 9 e 17 anos de ambos os sexos. Analisamos também se a prática regular de exercícios físicos beneficia, em relação as variáveis concernentes à pressão arterial, este grupo de indivíduos. A avaliação da pressão arterial foi realizada através da monitorização ambulatorial da pressão arterial durante 24 horas por ser uma forma de avaliação que oferece maior reprodutibilidade dos valores e maior detalhamento sobre o comportamento da pressão arterial nos diferentes períodos do dia. Foi utilizada a estatística descritiva para apresentar os resultados obtidos, a correlação de Pearson e Spearman para avaliar as associações entre as variáveis e a regressão linear múltipla para controlar os fatores de confusão e avaliar os preditores das variáveis de desfecho. Conclui-se que o índice de massa corporal se associa diretamente com a pressão arterial ambulatorial sistólica diurna e com a pressão arterial ambulatorial sistólica de 24 horas, independentemente de outras variáveis antropométricas. A estatura e o índice de massa corporal se associam diretamente à pressão arterial ambulatorial sistólica diurna e a pressão arterial ambulatorial média diurna neste grupo de pré-adolescentes e adolescentes. A relação cintura/quadril é significativamente menor naqueles que praticam exercícios físicos regularmente. / We observed the growing incidence and prevalence of cardiovascular diseases nowadays in the pediatric population. The aim of this study was to verify the association betwen ambulatory blood pressure and anthropometrical variables in 34 pre-teenagers and teenagers, ranging from 9 to 17 years old both male and female. We also analyzed if the frequent practice of exercices helps group of individuals in relation to this blood pressures variables. The blood pressure was evaluated by 24-h ambulatory blood pressure monitoring since this offers a better values reproducibility and more details about blood pressure behavior in diferences times of the day. We used descriptive statistics to present the final results and applied Pearson and Spearman tests to evaluated the association betwen the variables. Finally, applied the multivariated regression analisys to control the confusion factors. Our conclusion was that the body mass index is directed associated with the daytime sistolic ambulatory blood pressure and the 24-h sistolic ambulatory blood pressure independently from any other anthropometric variable. The height and the body mass index are directly associated to the daytime sistolic ambulatory blood pressure and the daytime average ambulatory blood pressure in this group. The waist-to-hip relation is smaller in the individuals that practice exercices regularly.
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Participação dos receptores histaminérgicos do tipo H1 e H2 presentes no núcleo medial da amígdala na resposta cardiovascular ao estresse. / Participação dos receptores histaminérgicos do tipo H1 e H2 presentes no núcleo medial da amígdala na resposta cardiovascular ao estresse.

Almeida, Daniela Oliveira de January 2012 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-10-23T17:18:48Z No. of bitstreams: 1 Daniela Almeida Participaçao dos receptores....pdf: 1297031 bytes, checksum: 754812103a71d951c868e902bd43f90c (MD5) / Made available in DSpace on 2012-10-23T17:18:48Z (GMT). No. of bitstreams: 1 Daniela Almeida Participaçao dos receptores....pdf: 1297031 bytes, checksum: 754812103a71d951c868e902bd43f90c (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / Situações de estresse repetido ou prolongado podem resultar em vários estados patológicos, como hipertensão arterial, arritmias cardíacas, infarto do miocárdio e até mesmo morte súbita. Embora se tenha muita informação sobre o controle cerebral da pressão arterial, as respostas cardiovasculares ao estresse não são totalmente compreendidas. Dados da literatura mostram a importância do núcleo medial da amigdala (MeA) e da neurotrasmissão histaminérgica no controle autonômico das funções cardiovasculares, no entanto, não há estudos evidanciando o papel das vias histaminérgicas no MeA nas adaptações cardiovasculares evocada pelo estresse emocional. Desta forma, o objetivo desta pesquisa foi estudar a participação dos receptores H1 e H2 no MeA sobre as respostas cardiovasculares em ratos estressados e não-estressados. Ratos Wistar (280-320g) foram submetidos à cirurgia estereotáxica para canulação bilateral do MeA. Passado cinco dias da estereotaxia, os animais foram submetidos a cateterização da artéria carótida esquerda. Vinte e quatro horas após a inserção do cateter, foram iniciados os experimentos com a gravação do registro da pressão arterial pulsátil (PAP) dos animais em condições basais e em livre movimento em suas respectivas caixas de forma continuada. As drogas utilizadas para a microinjeção central foram a mepiramina (antagonista dos receptores H1) nos grupos experimentais I e III e a cimetidina (antagonista dos receptores H2) nos grupos experimentais II e IV. Nos grupos experimentais I e II, 15 min após microinjeção central bilateral de mepiramina ou cimetidina respectivamente, em diferentes doses, os animais foram submetidos a estresse de restrição de movimentos em tubos de polietileno, e a PAP foi registrada continuamente durante 45 min. Após o período de estresse, os animais foram realocados em suas caixas e a PAP foi registrada por mais 30 min. Nos grupos experimentais III e IV, após as microinjeções centrais bilaterais no MeA, a PAP continuou sendo registrada por 75 min em animais sob condições basais e em livre movimento (não estressados). Os animais controles de todos os grupos experimentais receberam microinjeções de salina 0,9%. Os experimentos foram realizados entre 7h00min às 13h00min e os animais não tiveram acesso à água ou ração durante o experimento. Os dados estão expressos como média±E.P.M das variações da PAM e FC. Microinjeções de mepiramina nas doses de 50, 100 e 200 nmol promoveu bloqueio dose-dependente da resposta hipertensiva evocada pelo estresse de restrição. A cimetidina (100 e 200 nmol) atenuou a resposta hipertensiva ao estresse apenas na maior dose utilizada. A resposta anti-hipertensiva ao estresse foi maior nos animais que receberam microinjeções de mepiramina do que de cimetidina nas mesmas doses. Nenhuma das drogas alterou a resposta taquicárdica típica do estresse. Mepiramina ou cimetidina foram incapazes de alterar a PAM ou a FC de animais não estressados. Os dados sugerem que as vias histaminérgicas presentes no MeA medeiam a resposta pressora sem alterar a taquicardia evocadas pelo estresse de restrição, ativando preferencialmente os receptores do tipo H1. Além disto, os dados confirmam a hipótese de que a via histaminérgica no MeA não exerce modulação tônica do sistema cardiovascular. A obtenção de dados adicionais relativos ao papel fisiológico dos receptores histaminérgicos centrais no controle das funções cardiovasculares se reveste de grande importância para as ciências biológicas e para a clínica médica, principalmente quando vinculada à variável estresse. Os resultados deste trabalho contribuem para o esclarecimento da participação destes receptores no controle das funções cardiovasculares. / Repeated long lasting experiences of stress situations may result in various pathologic states such as arterial hypertension, cardiac dysrhythmias, myocardial stroke and even sudden death. Although there is a lot information about the neural control of the arterial blood pressure, especially by the brain stem and some other prosencephalic areas, stress-evoked cardiovascular responses are not totally understood. Previews studies shows the importance of the medial amygdala nucleus (MeA) and of the histaminergic neurotransmission on the autonomic control of cardiovascular functions, however there aren’t studies that evidence the role of the histaminergic pathways in MeA on emotional stress-evoked cardiovascular adaptations. Therefore, the aim of this study was investigate the participation of the histaminergic receptors H1 and H2 in MeA on the cardiovascular responses in stressed and non-stressed rats. Wistar rats (280-320g) were submitted to stereotaxic surgery for bilateral cannulation of MeA. Five days after surgery, animals were submitted to catheterization of the left carotid artery. Twenty four hours after catheter insertion, experiments were started and the pulsatile arterial pressure (PAP) of freely moving rats on basal conditions was recorded. Drugs used for central administration were mepyramine (H1 receptors antagonist) on experimental groups I and III and cimetidine (H2 receptors antagonist) on experimental groups II and IV. At experimental groups I and II, 15 min after central microinjections of mepyramine or cimetidine respectively, in different doses, the rats was submitted to restraint stress in a polyvinyl apparatus, and PAP were continuously recorded for 45 min. After stress period, rats were replaced in their own cages and an additional 30 min were recorded for PAP reestablishment. At experimental groups III and IV, after 30 min of basal recording, rats received bilateral central microinjections of mepyramine or cimetidine in a dose of 200 nmol, respectively, and an additional period of 75 min was recorded in freely moving rats on basal conditions. Saline 0,9% was administered as vehicle in control animals of all experimental groups. Mean arterial pressure (MAP) and heart rate (HR) were, then, calculated from the PAP signal. Experiments occurred between 7:00 and 13:00 and rat did not have access to water and food during the sessions. Data were expressed as mean±S.E.M. of MAP and HR variation. Mepyramine microinjections at doses of 50, 100 and 200 nmol promoted dose-dependent blockade of the restraint stress-evoked hypertensive response. Cimetidine (100 and 200 nmol) attenuated the hypertensive response to stress only at the highest dose administered. The anti-hypertensive response was bigger on animals which received mepyramine than cimetidine. Neither drugs altered the typical stress-evoked tachycardiac responses. Indeed, mepyramine or cimetidina were unable to modify the MAP or HR of freely moving rats on basal conditionals (non-stressed rats). These data suggest that histaminergic pathways in MeA mediates pressor responses without modifying the tachycardia promoted by restraint stress, activating preferentially H1 receptors. Besides, data corroborate to the hypothesis that histaminergic pathways in MeA do not plays tonic modulation of the cardiovascular system. Additional information acquired about physiologic role of central histaminergic receptor on the cardiovascular functions is important to biological science and to medical practice, especially when linked to the stress factor. These data contribute to clarify the role of these receptors on cardiovascular functions

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