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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.
71

Influência da sobrecarga de líquidos sobre estado nutricional, gasto energético de repouso e biomarcador de risco cardiovascular em pacientes tratados por diálise peritoneal / Influence of fluid overload on nutritional status, resting energy expenditure and biomarker of cardiovascular risk in patients treated by peritoneal dialysis

Nathália Zanon dos Santos 21 November 2016 (has links)
A sobrecarga hídrica (SH) é um achado comum em pacientes em diálise peritoneal (DP) e a inadequação do estado nutricional aumenta a morbimortalidade nesta população. A bioimpedância elétrica é um método rápido e não-invasivo para estimar os compartimentos corporais, incluindo a distribuição dos fluídos corporais nos espaços intra e extracelulares. O principal objetivo foi avaliar se a SH interfere em estado nutricional, composição corporal, gasto energético de repouso e um biomarcador de risco cardiovascular, em pacientes com Doença Renal Crônica tratados por DP. Caracterizou-se como um estudo observacional transversal, realizado no Hospital das Clínicas da FMRP-USP. Foram avaliados dados de composição corporal e estado hídrico por Bioimpedância Elétrica de Frequência Simples (BIA) e Bioimpedância Elétrica Multifrequência de Espectroscopia (BIS), a concentração sérica do peptídeo natriurético atrial (Nt pro - BNP) como biomarcador de risco cardiovascular, dados antropométricos, de consumo alimentar, gasto energético de repouso (GER), exames bioquímicos e dados clínicos de rotina dos pacientes. Trinta pacientes foram incluídos e classificados em normohidratados (NH) ou hiperhidratados (HH), pelo valor de sobrecarga hídrica de 1,1 L. Para análise estatística, o nível de significância foi pré-fixado em ?= 0,05. Os pacientes HH, em comparação aos NH, apresentaram além de maior sobrecarga hídrica (3,54 L ± 1,7 X 0,14 ± 0,6), maiores valores em água corporal total (ACT - 34,98 L ± 4,74 X 30,43 L ± 5,45), água extracelular (AEC - 17,91 L ± 2,87 X 13,84 L ± 2,30) e menores valores de ângulo de fase (4,02° ± 0,81 X 5,51° ± 0,77) na avalição por BIS; o Nt Pró - BNP mostrou-se maior nos HH (7686 pg/ml ± 8872 X 1334 pg/ml ± 1034). Não houve diferença significativa entre os grupos para dados antropométricos, nos demais exames bioquímicos, em aferições da força de preensão palmar, nas pontuações do MIS (Malnutrition Inflammation Score), nos dados de ingestão alimentar, e nem no GER. O grupo com sobrecarga hídrica mostrou, de fato, uma maior concentração de água em compartimento extracelular, possivelmente gerando aumento em Nt pro - BNP e menor ângulo de fase. Quando avaliado o grupo como um todo, os métodos (BIA e BIS) mediram os resultados igualmente somente no que se refere à resistência (p = 0,71). Sendo a ACT, água intracelular (AIC), AEC, massa livre de gordura (MLG), massa celular corporal (MCC) e ângulo de fase maiores na medições da BIA e somente massa gorda maior nas medições da BIS; correlações mostraram que os dados de massa livre de gordura e massa celular corporal foram os que mais se distanciaram, com coeficientes mais fracos, enquanto que as demais variáveis apresentaram forte correlação. Para o diagnóstico nutricional em vigência de sobrecarga líquida, deve-se considerar um conjunto de variáveis interpretadas de maneira complementar, possibilitando um diagnóstico nutricional mais detalhado. O uso rotineiro da BIS pode ajudar a refinar a avaliação do estado de hidratação e composição corporal destes pacientes em DP. / The fluid overload (FO) is a common finding in patients on peritoneal dialysis (PD) and the inadequacy of the nutritional status increases the morbidity and mortality in this population. The bioelectrical impedance is a quick and non-invasive method to estimate body compartments, including the distribution of body fluids in intra- and extracellular spaces. The main objective was to assess whether the FO affects body cell mass, nutritional status, resting energy expenditure and a biomarker of cardiovascular risk in patients with chronic kidney disease treated by PD. It is characterized as a cross-sectional observational study conducted at the Hospital of FMRP-USP. We evaluated data of body composition and water status by Simple Frequency Electric Bioimpedance (BIA) and Electric Multifrequency Spectroscopy Bioimpedance (BIS), the serum concentration of atrial natriuretic peptide (NT pro - BNP) as a biomarker of cardiovascular risk, anthropometric data, food intake, resting energy expenditure (REE), biochemical and clinical data from routine patient. Thirty patients were included and classified into normal hydration (NH) or hyper hydrated (HH) by fluid overload value of 1.1 L. For statistical analysis, the level of significance was pre-set at ? = 0.05. HH patients, compared to NH, presented in addition to increased fluid overload (3.54 L ± 1.7 X 0.14 ± 0.6), higher values in total body water (TBW - 34.98 L ± 4.74 ± 5.45 x 30.43 L), extracellular water (ECW - L 17.91 ± 2.87 X 13.84 ± 2.30 L) and smaller phase angle values (± 4.02 ° 0.81 X 5.51 ± 0.77 °) in a BIS appraisal; the Nt Pro - BNP was higher in HH (7686 pg / ml ± 8872 X 1334 pg / ml ± 1034). There was no significant difference between groups for anthropometric data, in other biochemical tests on measurements of grip strength, in scores of MIS (Malnutrition Inflammation Score), the food intake data, and not the REE. The group with fluid overload shows, in fact, a higher concentration of water in the extracellular compartment, possibly generating an increase in NT pro - BNP and lower phase angle. When evaluated the group as a whole, the methods (BIA and BIS) measure only the results also as regards the resistance (p = 0.71). And TBW, intracellular water, ECW, fat-free mass, body cell mass and larger phase angle measurements in the BIA and only greater fat mass in measurements of BIS; correlations show that free mass data of fat and body cell mass are the ones who are more distanced, with weaker coefficients, while the other variables are strongly correlated. For the nutritional diagnosis of fluid overload force, should be considered a set of variables interpreted in a complementary manner, enabling a more detailed nutritional diagnosis. The routine use of BIS can help refine the assessment of hydration status and body composition of these patients on PD.
72

Extraction and analysis of interstitial fluid, and characterisation of the interstitial compartment in kidney disease

Ebah, Leonard January 2012 (has links)
Kidney failure results in fluid and toxin accumulation within body fluid compartments, contributing to the excess mortality seen in this condition. Such uremic toxins have been measured in plasma, with levels assumed to reflect extraplasmatic concentrations such as in interstitial fluid (ISF). ISF is separated from plasma by nanometre-order microvascular pores; toxins may not circulate “freely” between the two compartments. This work set out to characterise the ISF in uremic subjects, with the hypothesis that there may be differences with plasma. Any such difference may be clinically relevant, owing to the much larger size of the ISF compartment, its proximity to cell metabolic processes, and its expansion in renal impairment.We used a modified microdialysis technique to successfully sample subcorneal ISF of some the uremic toxins (urea, creatinine, urate, phosphate). Reverse iontophoresis (RI) was also used as a non-invasive technique to sample epidermal ISF of urea. Hollow microneedles were developed and their ability to extract ISF tested in CKD patients and controls. The mechanical properties (pressure, volume, permeability) and biochemical composition (proteomic and metabolomic profiles) of the interstitial compartment were also investigated.Microdialysis and RI performed very well as interstitial uremic toxin sampling techniques. Small differences were seen in steady states between ISF and plasma urea, creatinine, phosphate and urate, with slightly lower ISF levels. Dialysis seemed to enhance this difference, with a lag in the clearance of ISF toxins seen in some patients, most remarkable with phosphate. Metabolomic analysis identified several uremic toxins in ISF, whilst proteomics found some significant differences between the two compartments, with toxins like beta-2 microglobulin occurring in ISF only. Microneedle arrays successfully extracted ISF in 68.8% of patients with oedema. Successful extraction of ISF with microneedles occurred mainly in oedematous patients, who were found to have raised interstitial pressures (ISP) and volumes. ISP correlated significantly with body fluid volumes and seemed time-dependent, lower in more chronic oedema. ISP and volumes also correlated with the oedema depitting time (after thumb pressure), a potential novel parameter that probably relates to tissue hydraulic conductivity and hence volume status and fluid mobility within the interstitium.This study demonstrates that interstitial fluid may need to be considered as a separate active compartment in patients with renal dysfunction, with a different “uremic" composition and unique pathophysiological characteristics that cannot be explained by blood compartment based measurements alone. There is a need for more studies, to further characterise this compartment and elucidate its importance.
73

Conception d’un système intégré de mesure de bioimpédance pour le suivi long terme de la composition des tissus biologiques / Design of an Integrated Bioimpedance Measurement System for Chronic Monitoring of Biological Tissue Composition

Lamlih, Achraf 26 November 2018 (has links)
Les techniques d'évaluation de la composition tissulaire permettent de mieux comprendre les processus physiologiques et leur impact global sur l'état biologique des sujets expérimentaux. Le travail présenté dans ce manuscrit vise à concevoir un système de mesure intégré de spectroscopie de bioimpédance capable de mesurer un large champ de biomarqueurs sur de longues périodes (jusqu'à un an). Le système de mesure présenté peut être utilisé pour des applications de suivi à long terme de variables physiologiques en général. Néanmoins, les solutions présentées visent en particulier le poisson dans le cadre du projet POPSTAR qui vise à améliorer notre compréhension du comportement des poissons en analysant non seulement l’environnement dans lequel les poissons se déplacent et vivent mais aussi les poissons eux-mêmes. Après avoir identifié les défis de conception d'un système de mesure intégré par spectroscopie de bioimpédance, nous avons proposé une nouvelle architecture hybride permettant une spectroscopie rapide tout en maximisant la précision des mesures. Les blocs de génération du signal d'excitation sont critiques car leurs performances affectent l'ensemble des performances de l'architecture. La deuxième partie de cette recherche porte donc sur la conception et l’optimisation de la partie génération de l’architecture. En effet, nous avons amélioré la qualité des signaux de génération de stimuli pour les excitations mono-fréquentielle et multi-fréquentielle tout en proposant pour cela des implémentations sur puce de basse complexité. Dans la dernière partie de notre travail, la source de courant analogique qui transforme les stimuli en un courant d'excitation est discuté. Pour ce bloc, nous avons proposé une nouvelle topologie analogique utilisant un version améliorée du cascode régulé et une compensation de rétroaction du mode commun indépendante des variations du processus. Le premier prototype de puce intégrée embarquant les blocs critiques de l'architecture de mesure de bioimpédance a été conçu et simulé avec un process CMOS 0.18 µm de AMS fonctionnant sous une tension d'alimentation de 1.8 V. / Tissue composition assessment techniques are used to help better comprehend physiological processes and their overall impact on the biological state of the experiments subjects. The research presented in this manuscript aims to design a bioimpedance spectroscopy integrated measurement system capable of measuring a wide range of biomarkers over long periods of time (up to one year). The presented measurement system can be used for physiological variables long time monitoring applications in general. Nevertheless, the presented solutions target in particular fish species in the context of the POPSTAR project which aims to enhance our understanding of fish behavior by analyzing not only the environment in which fish travel and live but also the fish themselves. After identifying the design challenges of a bioimpedance spectroscopy integrated measurement system, we have proposed a novel hybrid architecture providing fast bioimpedance spectroscopy while maximizing the measurement precision. As the signal generation blocks are critical and their performances affect the whole architecture performances. The second part of this research focuses on the design and optimization of the signal generation part of the architecture. Indeed, we have enhanced the stimuli generation signals quality for single tone and multitone excitations while proposing for this blocks low complexity on-chip implementations. In the last part of our work the current driver that transforms the voltage stimuli into an excitation current is discussed. A novel analog topology using an improved regulated cascode and a common-mode feedback compensation independent of process variations is presented. The first chip prototype implementing the critical blocks of the bioimpedance integrated measurement architecture has been designed and simulated in a 0.18 µm AMS (Austria MicroSystems) CMOS process operating at 1.8 V power supply.
74

Die Bioimpedanzanalysatoren Body Composition Monitor und Nutriguard-M in der Dialysetherapie - ein Gerätevergleich

Pohl, Jacqueline 02 October 2014 (has links)
Die Bestimmung des Sollgewichts von Dialysepatienten stellt einen Balanceakt zwi-schen Hyper- und Hypovolämie und damit zwischen ischämischen Ereignissen durch Hypotonie und kardiovaskulären Komplikationen dar. Derzeit wird es anhand gering sensitiver bzw. unspezifischer und meist subjektiver klinischer Methoden ermittelt. Die Bioimpedanzanalyse als objektives, nicht invasives und zeitsparendes Verfahren steht zunehmend im Mittelpunkt von Studien, die der Behandlung von Dialysepatienten gewidmet sind. In dieser Arbeit wird die Untersuchung von 40 Patienten mit den Bioimpedanzanalysatoren Body Composition Monitor von Fresenius und Nutriguard-M von Data Input sowie mit klinischen Methoden beschrieben. Der Body Composition Monitor errechnet die Überwässerung des Patienten im Rahmen der Messung. Für die Berechnung der Überwässerung aus vom Nutriguard-M gemessenen Daten wurde eigens eine Formel erstellt. Obgleich hohe absolute Unterschiede zwischen den mittels der Bioimpedanzanalysatoren und der klinisch bestimmten Werte für die Überwässerung beobachtet wurden, waren positive Korrelationen der durch Bioimpedanzsanalyse gemessenen Überwässerung mit klinischen Parametern, wie dem Durchmesser der V. cava inferior, der Ausprägung von Unterschenkelödemen und dem mittleren arteriellen Blutdruck zum Nadir der Dialyse feststellbar. Verglichen wurden die Geräte nicht nur auf der Ebene der gemessenen Überwässerung, sondern auch auf den Ebenen der Rohwerte und der Anteile der Körperkompartimente am Körpergewicht. Dabei zeigten sich in Abhängigkeit des Verarbeitungsgrades der durch die Geräte gemessenen bzw. berechneten Größen sowohl geringe als auch hohe Abweichungen. Diese Erkenntnisse relativieren die Euphorie über die Möglichkeit der Anwendung der BIA in der Dialysetherapie.:1. Einleitung 2. Patienten, Material und Methoden 3. Ergebnisse 4. Diskussion 5. Zusammenfassung
75

Techniques to assess volume status and haemodynamic stability in patients on haemodialysis

Mathavakkannan, Suresh January 2010 (has links)
Volume overload is a common feature in patients on haemodialysis (HD). This contributes significantly to the cardiovascular disease burden seen in these patients. Clinical assessments of the volume state are often inaccurate. Techniques such as interdialytic blood pressure, relative blood volume monitoring, bioimpedance are available to improve clinical effectives. However all these techniques exhibit significant shortcomings in their accuracy, reliability and applicability at the bed side. We evaluated the usefulness of a dual compartment monitoring technique using Continuous Segmental Bioimpedance Spectroscopy (CSBIS) and Relative Blood Volume (RBV) as a tool to assess hydration status and determine dry weight. We also sought to evaluate the role of Atrial Natriuretic Peptide (ANP) and B-type Natriuretic Peptide (BNP) as a volume marker in dialysis patients. The Retrospective analysis of a historical cohort (n = 376, 55 Diabetic) showed a significant reduction in post-dialysis weights in the first three months of dialysis (72.5 to 70kg, p<0.027) with a non-significant increase in weight between months 6-12. The use of anti-hypertensive agents reduced insignificantly in the first 3 months, increased marginally between months 3-6 and significantly increased over the subsequent 6 months. The residual urea clearance (KRU) fell and dialysis times increased. The cohort was very different to that dialysing at Tassin and showed a dissociation between weight reduction and BP control. This may relate to occult volume overload. CSBIS-RBV monitoring in 9 patients with pulse ultrafiltration (pulse UF) showed distinct reproducible patterns relating to extra cellular fluid (ECF) and RBV rebound. An empirical Refill Ratio was then used to define the patterns of change and this was related to the state of their hydration. A value closer to unity was consistent with the attainment of best achievable target weight. The refill ratio fell significantly between the first (earlier) and third (last) rebound phase (1.97 ± 0.92 vs 1.32 ± 0.2). CSBIS monitoring was then carried out in 31 subjects, whilst varying dialysate composition, temperature and patient posture to analyse the effects of these changes on the ECF trace and to ascertain whether any of these interventions can trigger a change in the slope of the ECF trace distinct to that caused by UF. Only, isovolemic HD caused a change in both RBV and ECF in some patients that was explained by volume re-distribution due to gravitational shifts, poor vascular reactivity, sodium gradient between plasma and dialysate and the use of vasodilating antihypertensive agents. This has not been described previously. These will need to be explored further. The study did demonstrate a significant lack of comparability of absolute values of RECF between dialysis sessions even in the same patient. This too has not been described previously. This is likely to be due to subtle changes in fluid distribution between compartments. Therefore a relative changes must be studied. This sensitivity to subtle changes may increase the usefulness of the technique for ECF tracking through dialysis. The potential of dual compartment monitoring to track volume changes in real time was further explored in 29 patients of whom 21 achieved weight reductions and were able to be restudied. The Refill Ratio decreased significantly in the 21 patients who had their dry weights reduced by 0.95 ± 1.13 kg (1.41 ± 0.25 vs 1.25 ± 0.31). Blood pressure changes did not reach statistical significance. The technique was then used to examine differences in vascular refill between a 36oC and isothermic dialysis session in 20 stable prevalent patients. Pulse UF was carried out in both these sessions. There were no significant differences in Refill Ratios, energy removed and blood pressure response between the two sessions. The core temperature (CT) of these patients was close to 36oC and administering isothermic HD did not confer any additional benefit. Mean BNP levels in 12 patients during isovolemic HD and HD with UF did not relate to volume changes. ANP concentrations fell during a dialysis session in 11 patients from a mean 249 ± 143 pg/ml (mean ± SD) at the start of dialysis to 77 ± 65 pg/ml at the end of the session (p<0.001). During isolated UF levels did not change but fell in the ensuing sham phase indicating a time lag between volume loss and decreased generation. (136±99 pg/ml to 101±77.2 pg/ml; p<0.02) In a subsequent study ANP concentrations were measured throughout dialysis and in the post-HD period for 2 hours. A rebound in ANP concentration was observed occurring at around 90 min post-HD. The degree of this rebound may reflect the prevailing fluid state and merit further study. We have shown the utility of dual compartment monitoring with CSBIS-RBV technique and its potential in assessing volume changes in real time in haemodialysis patients. We have also shown the potential of ANP as an independent marker of volume status in the same setting. Both these techniques merit further study.
76

Modular textile-enabled bioimpedance system for personalized health monitoring applications

Ferreira, Javier January 2017 (has links)
A growing number of factors, including costs, technological advancements, ageing populations, and medical errors, are leading industrialized countries to invest in research on alternative solutions to improve their health-care systems and increase patients’ quality of life. Personal health systems (PHS) examplify the use of information and communication technologies that enable a paradigm shift from the traditional hospital-centered healthcare delivery model toward a preventive and person-centered approach. PHS offer the means to monitor a patient’s health using wearable, portable or implantable systems that offer ubiquitous, unobtrusive biodata acquisition, allowing remote monitoring of treatment and access to the patient’s status. Electrical bioimpedance (EBI) technology is non-invasive, quick and relatively affordable technique that can be used for assessing and monitoring different health conditions, e.g., body composition assessments for nutrition. When combined with state-of-the-art advances in sensors and textiles, EBI technologies are fostering the implementation of wearable bioimpedance monitors that use functional garments for personalized healthcare applications. This research work is focused on the development of wearable EBI-based monitoring systems for ubiquitous health monitoring applications. The monitoring systems are built upon portable monitoring instrumentation and custom-made textile electrode garments. Portable EBI-based monitors have been developed using the latest material technology and advances in system-on-chip technology. For instance, a portable EBI spectrometer has been validated against a commercial spectrometer for total body composition assessment using functional textile electrode garments. The development of wearable EBI-based monitoring units using functional garments and dry textile electrodes for body composition assessment and respiratory monitoring has been shown to be a feasible approach. The availability of these measurement systems indicates progress toward the real implementation of personalized healthcare systems. / <p>QC 20170517</p>
77

Associa??o do n?vel de atividade f?sica e do tempo sentado com o ?ngulo de fase da bioimped?ncia

Mundstock, Eduardo 15 March 2018 (has links)
Submitted by PPG Pediatria e Sa?de da Crian?a (pediatria-pg@pucrs.br) on 2018-05-21T13:54:31Z No. of bitstreams: 1 Tese_Eduardo_Mundstock Versao Final.pdf: 1978473 bytes, checksum: 4be8f1b605788a6e254263a3c448a60f (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-06-06T18:34:35Z (GMT) No. of bitstreams: 1 Tese_Eduardo_Mundstock Versao Final.pdf: 1978473 bytes, checksum: 4be8f1b605788a6e254263a3c448a60f (MD5) / Made available in DSpace on 2018-06-06T18:36:11Z (GMT). No. of bitstreams: 1 Tese_Eduardo_Mundstock Versao Final.pdf: 1978473 bytes, checksum: 4be8f1b605788a6e254263a3c448a60f (MD5) Previous issue date: 2018-03-15 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Introduction: The phase angle is considered an important prognostic marker because it reflects cellular health. Inadequate physical activity and sitting time are associated with a significant number of chronic noncommunicable diseases. Recent studies suggest that these two factors may be associated with phase angle values. Objective: to verify the association of phase angle with physical activity Methodology: the thesis will present two articles: a systematic review with metaanalysis and a cross-section article. Meta-analysis: We searched the following databases: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, SciELO, LILACS, SPORTDiscus, Scopus and Web of Science. Two reviewers independently assessed eligibility criteria and bias risks. The results were synthesized using random effects models. The association between physical activity and phase angle was evaluated considering the design of the study. Cross-sectional study: individuals over 11 years of age, of both sexes, who met bioimpedance assessment criteria and without diagnosis of chronic disease, were invited to participate in the study. The phase angle evaluation was performed using Ottoboni's Biospace equipment, model InBodyS10. Physical activity level and sitting time were assessed using the International Physical Activity Questionnaire (IPAQ). The association between the phase angle and the predictor variables was evaluated using a univariate and multivariate generalized linear model (GLM). All variables with a value of p <0.20 were included in the multivariate model. In the final model, only the variables with p <0.05 were included. Results: Systematic Review: Nine studies, totaling 575 participants, were included in the meta-analysis. The results of cross-sectional studies indicate that the active subjects presented a mean value of higher phase angle when compared to controls (DM = 0.70, 95% CI 0.48 to 0.92, P <0.001), with low heterogeneity (I2 = 0%, P = 0.619). In the crosssectional analysis, the differences between health status and type of physical activity evaluation were not significant (P = 0.332, P <0.253). In longitudinal studies (clinical trial and follow-up), mean values of final phase angle increased significantly compared to baseline (DM = 0.30, 95% CI 0.11 to 0.49, P <0.001), with low heterogeneity (I2 = 13%, P = 0.331). The differences were not significant in relation to the state of health and the type of longitudinal study (clinical trials or follow-up studies) (P = 0.900; 0.989). Evidence of publication bias was not observed, and the overall risk of bias was moderate to high. Cross-sectional article: 1228 subjects were included. The multivariate generalized linear model showed that both physical activity (? = 0.164, 95% CI 0.071 to 0.256, P = 0.001) and sitting time (? = 0.152, 95% CI 0.063 to 0, 242, P = 0.001) were determinant for the phase angle. As well as sex, body mass index and age, also remained associated with phase angle (? = -0.890, 95%CI -0.975 to -0.806, P <0.001; ? = 0.037, 95%CI 0.029 to 0,045, p <0.001 e; ? = -0.006, 95%CI -0.008 to -0.003 P<0.001, respectively). Conclusion: The results of the systematic review and the cross-sectional article suggest an association of phase angle with physical activity and sitting time. Among the main factors that may explain the positive effect of physical activity on the phase angle are the increase in cell membrane integrity and the change in intracellular content, these factors reflecting the cellular health and, consequently, the health of the individual. / Introdu??o: O ?ngulo de fase est? sendo considerado um importante marcador progn?stico, pois reflete a sa?de celular. A atividade f?sica inadequada e o tempo sentado est?o associados a um n?mero importante de doen?as cr?nicas n?o transmiss?veis. Estudos recentes sugerem que esses dois fatores podem estar associados com os valores do ?ngulo de fase. Objetivo: verificar a associa??o do ?ngulo de fase com a atividade f?sica. Metodologia: a tese ir? apresentar dois artigos: uma revis?o sistem?tica com metan?lise e um artigo transversal. Metan?lise: foram realizadas buscas nas seguintes bases de dados: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, SciELO, LILACS, SPORTDiscus, Scopus e Web of Science. Dois revisores avaliaram independentemente os crit?rios de elegibilidade e o risco de vi?s. Os resultados foram sintetizados mediante modelos de efeitos aleat?rios. A associa??o entre atividade f?sica e ?ngulo de fase foi avaliada considerando o desenho do estudo. Artigo transversal: os indiv?duos com mais de 11 anos de idade, de ambos os sexos, que atendiam aos crit?rios de avalia??o da bioimped?ncia e sem diagn?stico de doen?a cr?nica, foram convidados a participar do estudo. A avalia??o do ?ngulo de fase foi realizada usando o equipamento Biospace, modelo InBodyS10, da Ottoboni. O n?vel de atividade f?sica e o tempo sentado foram avaliados com o question?rio internacional de atividade f?sica (IPAQ). A associa??o entre o ?ngulo de fase e as vari?veis preditoras foram avaliadas utilizando um modelo linear generalizado univari?vel e multivari?vel (MLG). Todas as vari?veis com um valor de p <0,20 foram inclu?das no modelo multivari?vel. No modelo final, apenas as vari?veis com p <0,05 foram inclu?das. Resultados: Revis?o Sistem?tica: Nove estudos, totalizando 575 participantes, foram inclu?dos na metan?lise. Os resultados dos estudos transversais indicam que os sujeitos ativos apresentaram um valor m?dio de ?ngulo de fase superior quando comparado aos controles (DM = 0,70; IC 95%: 0,48 a 0,92, P <0,001), com baixa heterogeneidade (I2 = 0%; P = 0,619). Na an?lise transversal, as diferen?as entre o estado de sa?de e o tipo de avalia??o da atividade f?sica n?o foram significativas (P = 0,332; P <0,253). Nos estudos longitudinais (ensaio cl?nico e acompanhamento), os valores m?dios do ?ngulo de fase finais aumentaram significativamente comparando com os valores iniciais (DM = 0,30; IC 95%: 0,11 a 0,49, P <0,001), com heterogeneidade baixa (I2 = 13%, P = 0,3314). As diferen?as n?o foram significativas, em rela??o ao estado de sa?de e ao tipo de estudo longitudinal (ensaios cl?nicos ou estudos de seguimento) (P = 0,900; 0,989). N?o encontramos evid?ncia de vi?s de publica??o e o risco geral de vieses foi de moderado a alto. Artigo transversal: foram inclu?dos 1228 indiv?duos. O modelo linear generalizado multivari?vel mostrou que tanto a atividade f?sica (? = 0,164, IC95% 0,071 a 0,256, P= 0,001) como o tempo sentado (? = 0,152, IC95% 0,063 a 0,242, P= 0,001) foram determinantes para o ?ngulo de fase. Assim como o sexo, o ?ndice de massa corporal e a idade tamb?m permaneceram associados com o ?ngulo de fase (? = -0,890, IC95% -0,975 a -0,806, P <0,001; ? = 0,037, IC95% 0,029 a 0,045, p <0,001 e; ? = -0,006, IC95% - 0,008 a -0,003 P<0,001, respectivamente). Conclus?o: Os resultados da revis?o sistem?tica e do artigo transversal sugerem uma associa??o do ?ngulo de fase com a atividade f?sica e com o tempo sentado. Entre os principais fatores que podem explicar o efeito positivo da atividade f?sica sobre o ?ngulo de fase est?o o aumento da integridade da membrana celular e a mudan?a no conte?do intracelular, fatores estes que refletem a sa?de celular e, consequentemente, a sa?de do indiv?duo.
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Avaliação da composição corporal por espectroscopia por bioimpedância em pacientes com síndrome nefrótica / Evaluation of the body composition by spectroscopy by bioimpedance in patients with nephrotic syndrome

Rodrigues, Aline Scharr 06 November 2018 (has links)
Síndrome nefrótica é definida pela presença simultânea de edema sistêmico, hipoalbuminemia e proteinúria intensa. Vários componentes da composição corporal, principalmente relacionados à água corporal, sofrem rápidas e frequentes alterações nessa síndrome. A espectroscopia por bioimpedância (BIS) é um método de fácil execução, baixo custo, que pode ser repetido e praticamente isento de riscos que permite avaliar água corporal, massa magra e gordura corporal e tem sido pouco utilizado na síndrome nefrótica. Objetivo. Avaliar as alterações da água e de outros componentes da composição corporal através da BIS em pacientes com síndrome nefrótica. Métodos. Pacientes foram avaliados na ocasião da biópsia renal e no desfecho com ou sem remissão do edema. Foram medidos o peso corporal, albumina sérica e proteinúria de 24 h e, pela BIS, variáveis relacionadas à água corporal e a outros parâmetros de composição corporal. Resultados. Foram estudados 17 pacientes (idade: 51,1 + 17,4 anos) com síndrome nefrótica. Dez pacientes obtiveram remissão do edema (grupo R), sendo que em nove ocorreu também remissão da síndrome nefrótica. Em sete pacientes o edema permaneceu presente, sem remissão (grupo SR). A variação entre a primeira e a segunda medida para a sobrecarga hídrica foi de -5,4 L (-8,5 L; -1,8 L) no grupo R e de 0,0 L (-1,1 L; 1,2 L) no grupo SR (p < 0,05). A água corporal total variou de -4,75 L (- 10,20 L; -2,50 L) e de 4,80 L (-1,30 L; 6,10 L) nos grupos R e SR, respectivamente (p < 0,05), e a água extracelular variou de -5,90 L (-10,10 L; -0,42 L) e de 1,20 L (-0,80 L; 2,70 L) nos mesmos grupos (p < 0,05). Não houve diferença estatisticamente significante na variação entre as duas avaliações nos grupos R e SR para a água intracelular, massa de tecido magro, massa de tecido adiposo, massa gorda total e massa celular corporal. A variação do ângulo de fase entre as avaliações foi de 1,55° (0,41°; 2,24°) no grupo R e 0,10° (-0,28°; 0,46°) no grupo SR (p < 0,05). Houve correlação estatisticamente significante entre cada variável definidora da síndrome nefrótica (peso corporal, proteinúria e albumina sérica) versus sobrecarga hídrica, água corporal total, água extracelular e ângulo de fase, mas não versus as demais medidas de composição corporal obtidas pela BIS. Conclusão. A espectroscopia por bioimpedância mostrou-se eficiente em detectar mudanças da água corporal e do ângulo de fase em pacientes com síndrome nefrótica, mas não para identificar variações relacionadas à massa de tecido magro, massa de tecido adiposo, massa gorda total e massa celular corporal. . / Nephrotic syndrome is established by the simultaneous presence of systemic edema, hypoalbuminemia, and severe proteinuria. Several components of the body composition, mainly related to the body fluid, undergo to rapid and frequent changes in this syndrome. Spectroscopy by bioimpedance (BIS) is a reliable, cost-effective and easy-to-perform method to evaluate body water, adipose tissue mass, and body cell mass. Despite these advantages, BIS has barely been used to evaluate patients with nephrotic syndrome. Aims. To evaluate body fluid variable changes and other components of the body composition in patients with nephrotic syndrome by bioimpedance spectroscopy. Methods. Patients were studied in two moments: at the occasion of the renal biopsy (1st evaluation), and at the end-point (2nd evaluation). Patients were grouped according to they reached remission (Group R) or remained without remission (Group WR) of the edema at the 2nd evaluation. Body weight, serum albumin and 24 hours proteinuria were measured at the two time-points, as well as other variables associated with body fluid and other components of the body composition obtained by the BIS. Results. Seventeen patients (age: 51,1 + 17,4 years-old) with nephrotic syndrome were studied. Ten patients reached remission of the edema while nine of them were also in remission of the nephrotic syndrome. Seven patients remained with edema at the end-point. The variation between the 1st and the 2nd measurement for the overhydration was of -5,4 L (-8,5L; -1,8L) at the group R and of 0,0 (-1,1 L; 1,2 L) at the group NR (p < 0,05). Total body water changes were of -4,75 L (-10,20 L; -2,50 L) and of 4,80 L (-1,30 L; 6,10 L) at the groups R and WR, respectively (p < 0,05), and the extracellular water changed of the -5,90 L (-10,10 L; -0,42 L) and of 1,20 L (-0,80 L; 2,70 L) at the same groups, respectively (p < 0,05). There was no statistically significant difference in the variation between the two evaluations for the groups R and NR for intracellular water, lean tissue mass, fat mass, adipose tissue mass, and body cell mass. The variation of the phase angle between the two evaluations was of the 1,55° (0,41°; 2,24°) at the group R and 0,10° (-0,28°; 0,46°) at the group WR (p < 0,05). There was a statistically significant correlation between each related nephrotic syndrome variable compared with overhydration, total body water, extracellular water, and phase angle, but no difference when compared with the other variables related to the body composition measured by the BIS. Conclusion. The spectroscopy by bioimpedance was efficient to measure body water changes and the phase angle in patients with nephrotic syndrome. However, the BIS could not detect changes related to the intracellular water, lean tissue mass, fat mass, adipose tissue mass, and body cell mass.
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Avaliação da composição corporal por espectroscopia por bioimpedância em pacientes com síndrome nefrótica / Evaluation of the body composition by spectroscopy by bioimpedance in patients with nephrotic syndrome

Aline Scharr Rodrigues 06 November 2018 (has links)
Síndrome nefrótica é definida pela presença simultânea de edema sistêmico, hipoalbuminemia e proteinúria intensa. Vários componentes da composição corporal, principalmente relacionados à água corporal, sofrem rápidas e frequentes alterações nessa síndrome. A espectroscopia por bioimpedância (BIS) é um método de fácil execução, baixo custo, que pode ser repetido e praticamente isento de riscos que permite avaliar água corporal, massa magra e gordura corporal e tem sido pouco utilizado na síndrome nefrótica. Objetivo. Avaliar as alterações da água e de outros componentes da composição corporal através da BIS em pacientes com síndrome nefrótica. Métodos. Pacientes foram avaliados na ocasião da biópsia renal e no desfecho com ou sem remissão do edema. Foram medidos o peso corporal, albumina sérica e proteinúria de 24 h e, pela BIS, variáveis relacionadas à água corporal e a outros parâmetros de composição corporal. Resultados. Foram estudados 17 pacientes (idade: 51,1 + 17,4 anos) com síndrome nefrótica. Dez pacientes obtiveram remissão do edema (grupo R), sendo que em nove ocorreu também remissão da síndrome nefrótica. Em sete pacientes o edema permaneceu presente, sem remissão (grupo SR). A variação entre a primeira e a segunda medida para a sobrecarga hídrica foi de -5,4 L (-8,5 L; -1,8 L) no grupo R e de 0,0 L (-1,1 L; 1,2 L) no grupo SR (p < 0,05). A água corporal total variou de -4,75 L (- 10,20 L; -2,50 L) e de 4,80 L (-1,30 L; 6,10 L) nos grupos R e SR, respectivamente (p < 0,05), e a água extracelular variou de -5,90 L (-10,10 L; -0,42 L) e de 1,20 L (-0,80 L; 2,70 L) nos mesmos grupos (p < 0,05). Não houve diferença estatisticamente significante na variação entre as duas avaliações nos grupos R e SR para a água intracelular, massa de tecido magro, massa de tecido adiposo, massa gorda total e massa celular corporal. A variação do ângulo de fase entre as avaliações foi de 1,55° (0,41°; 2,24°) no grupo R e 0,10° (-0,28°; 0,46°) no grupo SR (p < 0,05). Houve correlação estatisticamente significante entre cada variável definidora da síndrome nefrótica (peso corporal, proteinúria e albumina sérica) versus sobrecarga hídrica, água corporal total, água extracelular e ângulo de fase, mas não versus as demais medidas de composição corporal obtidas pela BIS. Conclusão. A espectroscopia por bioimpedância mostrou-se eficiente em detectar mudanças da água corporal e do ângulo de fase em pacientes com síndrome nefrótica, mas não para identificar variações relacionadas à massa de tecido magro, massa de tecido adiposo, massa gorda total e massa celular corporal. . / Nephrotic syndrome is established by the simultaneous presence of systemic edema, hypoalbuminemia, and severe proteinuria. Several components of the body composition, mainly related to the body fluid, undergo to rapid and frequent changes in this syndrome. Spectroscopy by bioimpedance (BIS) is a reliable, cost-effective and easy-to-perform method to evaluate body water, adipose tissue mass, and body cell mass. Despite these advantages, BIS has barely been used to evaluate patients with nephrotic syndrome. Aims. To evaluate body fluid variable changes and other components of the body composition in patients with nephrotic syndrome by bioimpedance spectroscopy. Methods. Patients were studied in two moments: at the occasion of the renal biopsy (1st evaluation), and at the end-point (2nd evaluation). Patients were grouped according to they reached remission (Group R) or remained without remission (Group WR) of the edema at the 2nd evaluation. Body weight, serum albumin and 24 hours proteinuria were measured at the two time-points, as well as other variables associated with body fluid and other components of the body composition obtained by the BIS. Results. Seventeen patients (age: 51,1 + 17,4 years-old) with nephrotic syndrome were studied. Ten patients reached remission of the edema while nine of them were also in remission of the nephrotic syndrome. Seven patients remained with edema at the end-point. The variation between the 1st and the 2nd measurement for the overhydration was of -5,4 L (-8,5L; -1,8L) at the group R and of 0,0 (-1,1 L; 1,2 L) at the group NR (p < 0,05). Total body water changes were of -4,75 L (-10,20 L; -2,50 L) and of 4,80 L (-1,30 L; 6,10 L) at the groups R and WR, respectively (p < 0,05), and the extracellular water changed of the -5,90 L (-10,10 L; -0,42 L) and of 1,20 L (-0,80 L; 2,70 L) at the same groups, respectively (p < 0,05). There was no statistically significant difference in the variation between the two evaluations for the groups R and NR for intracellular water, lean tissue mass, fat mass, adipose tissue mass, and body cell mass. The variation of the phase angle between the two evaluations was of the 1,55° (0,41°; 2,24°) at the group R and 0,10° (-0,28°; 0,46°) at the group WR (p < 0,05). There was a statistically significant correlation between each related nephrotic syndrome variable compared with overhydration, total body water, extracellular water, and phase angle, but no difference when compared with the other variables related to the body composition measured by the BIS. Conclusion. The spectroscopy by bioimpedance was efficient to measure body water changes and the phase angle in patients with nephrotic syndrome. However, the BIS could not detect changes related to the intracellular water, lean tissue mass, fat mass, adipose tissue mass, and body cell mass.
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Composição corporal em pacientes com doença inflamatória intestinal: antropometria versus bioimpedância / Body composition of patients with inflamatory bowel disease: antropometry versus bioimpedance

Viviane Abrantes Jardim 25 March 2013 (has links)
A Doença Inflamatória Intestinal (DII) é uma desordem caracterizada pela inflamação difusa do trato gastrointestinal. Os dois principais tipos de DII são a Retocolite Ulcerativa (RCU) e a Doença de Crohn (DC) e ambas cursam com alterações no estado nutricional (EN). O objetivo deste estudo foi comparar a composição corporal, obtida por meio de diferentes métodos, em pacientes com DC e RCU em atendimento ambulatorial, avaliando possíveis diferenças nos grupos de doentes entre si e quando comparados a indivíduos saudáveis. Foi realizado um estudo transversal incluindo 101 pacientes com DII, sendo 50 com DC (GDC) e 51 com RCU (GRCU), além de 35 indivíduos saudáveis (GCON), selecionados no Ambulatório do Hospital Universitário Pedro Ernesto (HUPE) da Universidade do Estado do Rio de Janeiro (UERJ). Informações sócio-demográficas e pessoais, como prática de exercício físico, tabagismo, doenças pregressas e procedimentos cirúrgicos prévios foram coletadas. A avaliação antropométrica consistiu de: peso; altura; circunferências do braço, da cintura e do quadril; circunferência muscular do braço (CMB) e pregas cutâneas do tríceps, bíceps, peitoral, axilar, subescapular, suprailíaca, supraespinhal, abdominal, perna e coxa. O percentual de gordura corporal (% GC) foi estimado a partir de equações que utilizam o somatório de pregas cutâneas e por meio de bioimpedância elétrica (BIA). Para estimar o percentual de gordura subcutânea foi utilizado o somatório de dez dobras. As variáveis laboratoriais analisadas foram: hemograma completo, proteínas totais, albumina, globulina, velocidade de hemossedimentação e proteína C reativa. As análises estatísticas foram realizadas utilizando-se o software STATA versão 10.0. A classificação do EN, por meio do índice de massa corporal (IMC), evidenciou baixa prevalência de desnutrição nos três grupos avaliados. Ao analisar diretamente as medidas antropométricas de peso e IMC, observou-se que os pacientes com DC apresentaram valores significativamente menores do que os indivíduos do grupo controle. A avaliação da CMB mostrou que os pacientes do GDC e GRCU apresentaram depleção de massa magra em comparação aos indivíduos do GCON, porém sem apresentar diferenças entre os dois grupos de pacientes com DII. Em relação ao %GC obtido por BIA não foram verificadas diferenças entre os três grupos de estudo. Ao se verificar o %GC com a utilização das fórmulas de Peterson, Durnin & Womersley e Jackson & Pollock (que utiliza o somatório de três dobras) observou-se que os pacientes com DC apresentaram tecido adiposo significativamente depletado em relação aos indivíduos do GCON e do GRCU. Ao compararmos os %GC obtidos por diferentes métodos de estimativa, observou-se que as equações de Jackson & Pollock (que utilizam o somatório de três e sete dobras) apresentaram resultados significativamente menores quando comparados aos das equações de Peterson e Durnin & Womersley, nos dois grupos de pacientes. Os níveis séricos de proteínas totais e albumina, e a contagem total de hemácias foram menores nos indivíduos com DC quando comparados aos indivíduos do grupo controle e/ou aos indivíduos do grupo com RCU. Os pacientes com DC apresentaram comprometimento importante do EN em comparação aos pacientes com RCU e, notadamente, em relação aos indivíduos saudáveis. / Inflammatory Bowel Disease (IBD) is a disorder characterized by diffuse inflammation of the gastrointestinal tract. The two main types of IBD are ulcerative colitis (UC) and Crohn's disease (CD), both coursing with changes in nutritional status (NS). The objective of this study was to investigate the existence of associations between body composition measured by electrical bioimpedance (BIA) and by the equations used for the estimate of fat percent in patients with CD and UC on ambulatory treatment and when compared to healthy individuals. A cross-sectional study was conducted on 101 patients with IBD, 50 of them with CD (GCD) and 51 with UC (GUC), and on 35 healthy subjects (GCON), selected at the Ambulatory of Pedro Ernesto University Hospital (HUPE) of the Rio de Janeiro State University (UERJ). Sociodemographic information such as practice of physical activity, smoking habit, previous diseases and surgical procedures was collected. Anthropometric evaluation consisted of weight; height; arm, waist and hip circumferences; arm muscle circumference (AMC), and the following skin folds: triceps, biceps, pectoral, axillary, subscapular, suprailiac, supraspinal, abdominal, leg, and thigh. Percent body fat (%BF) was estimated using equations based on the sum of skin folds and by BIA. Percent subcutaneous fat was estimated as the sum of ten folds. The laboratory variables analyzed, included: complete blood count, total protein, albumin, globulin, erythrocyte sedimentation rate, and C-reactive protein. Data were analyzed statistically using the STATA software, version 10.0. Classification of NS based on body mass index (BMI) revealed a low prevalence of malnutrition in the groups evaluated. Direct analysis of weight and BMI measurements revealed that patients with CD had significantly lower values than GCON individuals. The evaluation of AMC showed that GCD and GUC patients had depleted lean mass compared to GCON individuals, with no difference between the two groups of patients with IBD. No differences in %BF determined by BIA were detected among the three study groups. When %BF was determined using the formulas of Peterson, Durnin & Womersley and Jackson & Pollock (which use the sum of three folds), patients with CD were found to have significantly depleted adipose tissue compared to GCON and GUC individuals. Comparison of %BF values obtained by different estimate methods showed that the equations of Jackson & Pollock (which use the sum of three and seven folds) yielded significantly lower results than the equations of Peterson and Durnin & Womersley for the two patient groups. Seric levels of total protein and albumin, as well as red blood cell count and relative count of lymphocytes were lower in the individuals with CD than the individuals of the control group and/or the patients with UC. Patients with CD showed significant involvement of NS compared to patients with UC and especially compared to healthy individuals.

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