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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.
51

A comparison of helium dilution and plethysmography in measuring static lung volumes

Guldbrand, Anna January 2008 (has links)
In order to examine the usefulness of the multi breath helium dilution method (MB) it was compared to the single breath helium dilution method (SB) and body plethysmography (BP). Residual volume (RV), total lung capacity (TLC) and vital capacity (VC) were measured in seventeen subjects with obstructive (11) or restrictive (6) lung disease and four normal subjects. With information from professional literature and current periodicals, advantages and disadvantages with all three methods were compared. ANOVA and Student's t-test were performed on the measurement results. The results of the statistical tests tell us there are differences among the methods in the group of obstructive patients. They also reveal a notable difference between the MB and SB methods when measuring the same parameter. In addition, it was noted that none of the existing sets of prediction equations fulfill the requirements established on high quality lung function testing. Although a thorough evaluation of the reproducibility of the method is still required, it appears to be a viable alternative to body plethysmography. We claim that measuring the above mentioned static lung volumes with only the single breath helium dilution method cannot be considered a satisfactory practice.
52

Efeitos agudos da pressão expiratória positiva na mobilidade toracoabdominal de pacientes com DPOC / Acute effects of positive expiratory pressure in the thoracoabdominal mobility of patients with COPD

Feitoza, Carla Lima 13 December 2016 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2018-07-17T20:55:37Z No. of bitstreams: 1 Carla Lima Feitoza.pdf: 1039396 bytes, checksum: 54b4b08906cba375881a20315af80122 (MD5) / Made available in DSpace on 2018-07-17T20:55:37Z (GMT). No. of bitstreams: 1 Carla Lima Feitoza.pdf: 1039396 bytes, checksum: 54b4b08906cba375881a20315af80122 (MD5) Previous issue date: 2016-12-13 / Introduction: Chronic obstructive pulmonary disease (COPD) is characterized by persistent obstruction that is usually progressive and associated with an inflammatory response in the airways and lungs, by harmful particles or gases. The thoracoabdominal mobility of COPD patients alters as a result of this obstructive process that causes permanent pulmonary hyperinflation, altering respiratory mechanics. As a result, physical efforts can increase minute ventilation by reducing the time to expiration, increasing this hyperinflation. Positive airway expiratory pressure (PEP) is a physiotherapeutic resource that helps reduce air trapping during exacerbations of the COPD patient, but little is known about the effects of PEP on pulmonary hyperinflation. As a rule, PEP with high pressures has been contraindicated. Objective: Evaluate the effects of physical effort and PEP on pulmonary hyperinflation and Thoracoabdominal mobility through optoeletronic plethysmography (OEP) in patients with COPD and in healthy individuals. Materials and Methods: Thoracoabdominal mobility was evaluated by OEP in 30 subjects, in two groups, 15 of them with GOLD (GDPOC) and 15 healthy subjects (GC), with a mean age of 58.1 ± 11 years, before and after a daily life simulation activity, up and down the step and before and after performing a series of exercise with PEP. Results: Both the age and the anthropometric data of the studied population as weight and height showed no difference. The spirometric variables showed a significant difference, in favor of the CG, as expected. There were no significant differences in the contribution of the thoracoabdominal compartments at rest between groups, except for Ti / Tot in the GDPOC, with median of 0.77 characterizing possible hyperinflation or respiratory muscle fatigue. After physical exertion, for 2 minutes, the GDPOC group showed an increase in the Abd contribution in thoracoabdominal movements, higher than CG (52.2 ± 12.6% vs. 41.1 ± 14.6%). After PEP, there was an increase of abdominal compartment in the subjects of the GDPOC (50.5 ± 19.1% x 36.9 ± 16.4%). After the PEP the patients of the GDPOC had a normalization of Ti / Ttot, with a median of 0.41. As the analysis of the compartments in the GDPOC there is a greater involvement of the abdominal compartment in three moments evaluated and after PEP this abdominal participation is also greater than in the CG. Conclusion: Physical effort and the use of PEP alter the participation of thoracic and abdominal compartments differently between groups and PEP in COPD seems to contribute to the reduction of hyperinflation. / Introdução: A doença pulmonar obstrutiva crônica (DPOC) é caracterizada por obstrução persistente que é geralmente progressiva e associada a uma resposta inflamatória nas vias aéreas e pulmões, por partículas ou gases nocivos. A mobilidade toracoabdominal de portadores de DPOC se altera em decorrência deste processo obstrutivo que causa hiperinsuflação pulmonar permanente, alterando a mecânica respiratória. Em decorrência disso, esforços físicos podem aumentar a ventilação minuto reduzindo o tempo hábil para a expiração, aumentando essa hiperinsuflação. A pressão expiratória positiva (PEP) é um recurso fisioterapêutico que auxilia na redução do aprisionamento de ar durante as exacerbações do paciente com DPOC, porém pouco se sabe sobre os efeitos do PEP em tal cirunstância de hiperinsuflação pulmonar, na qual, via de regra, a PEP com altas pressões tem sido contraindicada. Objetivo: Avaliar os efeitos da pressão expiratória positiva na mobilidade toracoabdominal e na hiperinsuflação induzida pelo exercício físico, por meio da Pletismografia optoeletrônica (POE). Material e Método: A mobilidade toracoabdominal foi avaliada pela POE em 30 indivíduos, em dois grupos, sendo 15 com DPOC nível II pelo GOLD (GDPOC) e 15 indivíduos saudáveis (GC), com idade média de 58,1±11 anos, antes e após uma atividade de simulação de vida diária, subir e descer degrau e, antes e após realizarem uma série de exercício com PEP. Resultados: Tanto a idade quanto os dados antropométricos da população estudada como peso e altura não mostraram diferença. Já as variáveis espirométricas mostraram diferença significativa, à favor do GC, conforme o esperado; não houve diferenças significativas na contribuição dos compartimentos toracoabdominal, em repouso, entre os grupos, com exceção do Ti/Tot no GDPOC, com mediana de 0,77 caracterizando possível hiperinsuflação ou fadiga muscular respiratória. Após o esforço físico, por 2 minutos, houve alteração na mobilidade toracoabdominal no grupo GDPOC, apresentou aumento da contribuição do compartimento abdominal, maior que o CG (52,2±12,6% x 41,1±14,6%). O mesmo aumento houve após a PEP, no GDPOC (50,5±19,1% x 36,9±16,4%). Após a PEP os pacientes do GDPOC tiveram uma normalização de Ti/Ttot, com mediana de 0,41. Quanto a análise dos compartimentos no GDPOC há uma participação maior do compartimento abdominal nos três momentos avaliados sendo que após PEP essa participação abdominal também é maior do que no GC. Conclusão: O esforço físico e o uso de PEP alteram a participação de compartimentos torácicos e abdominais, de forma diferente entre os grupos e, a PEP na DPOC parece contribuir para a redução da hiperinsuflação.
53

Adaptations respiratoires et locomotrices des sujets obèses lors du test de marche de six minutes / Respiratory and locomotor adaptations of obese subjects during 6 minute walk test

Retory, Yann 25 January 2017 (has links)
La méthode de référence pour l’évaluation de la capacité d’exercice est l’Exploration Fonctionnelle d’eXercice (EFX). En pratique, pour des problèmes de coût, de matériel et d’expertise médicale, l’EFX n’est pas réalisée chez tous les sujets dont la capacité d’exercice mérite d’être explorée. Le test de marche de 6 minutes (6MWT) ne présente pas ces inconvénients mais ne donne pas d’informations sur les adaptations physiologiques au cours de cet exercice. L’objectif de ce travail de thèse était de concevoir une méthode non invasive de monitorage des adaptations ventilatoires et locomotrices. L’accent a été porté sur le respect du caractère spontané de ces adaptations. La pléthysmographie respiratoire d’inductance (RIP) et l’accélérométrie ont été choisies pour l’évaluation de ces adaptations. Les performances de ces nouvelles méthodes de monitorage sont acceptables pour ces deux dimensions. La confrontation de notre méthode RIP au pneumotachographe, outil de référence, objective des coefficients de corrélations compris entre 0,81 et 0,96 pour le volume courant(Vt), les temps inspiratoires (Ti) et expiratoires (Te). De même, la confrontation de notre méthode accélérométrique avec le contrôle vidéographique montre des coefficients de corrélations de 0,99 pour les paramètres locomoteurs : cadence, longueur moyenne du pas et détermination automatique des distances parcourues (6MWD). La comparaison des profils ventilatoires et locomoteurs entre contrôles et sujets obèses révèle qu’une discrimination est possible (p<0,01 pour Vt, Ti, Te et p<0 ,001 pour cadence, longueur moyenne de pas et 6MWD). Ainsi, même une population sans pathologie respiratoire comme la population obèse sans comorbidités, choisie comme modèle d’étude dans ce travail, peut être discriminée par notre méthode de monitorage. Ces résultats sont encourageants au regard de l’amélioration de la prise en charge des sujets obèses et laissent entrevoir des perspectives tant au niveau technologique qu’à un niveau clinique plus large pour, par exemple, les sujets atteints de pathologies respiratoires susceptibles de limiter leur capacité d’effort. / The reference method for assessment of exercise capacity is the cardio-pulmonary exercise testing (CPET). Nevertheless, CPET is expensive, time consuming, requires specifics skills and is not used for all subjects needing exercise capacity assessment. The 6 minute walk test (6MWT) is free of these disadvantages but does not give basic information about physiological adaptation induced by walking. The aim of this study was to design a non-invasive method for ventilatory and locomotor monitoring. Respect of the spontaneous aspects of these adaptations was considered. Respiratory inductive plethysmography (RIP) was considered for ventilatory evaluation whereas locomotor adaptation was assessed with a tri-axial accelerometer. These new methods provided acceptable results for ventilatory and locomotor dimensions. Confronting our new RIP method with a pneumotachograph as a reference device, we found correlation coefficients from. 0.81 to 0.96 for determination of tidal volume (Vt), inspiratory (Ti) and expiratory time (Te). Confronting our accelerometric method with video recordings as control, we found significant correlation coefficients (r=0.99 and p< 0.001) for determination of cadence, mean step length and automatic distance covered (6MWD) during the 6MWT. Comparisons of ventilatory and locomotor pattern of control and obese without comorbidities showed that discriminating their pattern was possible (p<0.01 for Vt, Ti, Te and p<0.001 for cadence, mean step length and 6MWD). These results imply that even a population without respiratory disorders as the obese population considered in this study, can be discriminated with our monitoring method. It can be concluded that this method is promising for improvement of care to obese subjects and raises technological and clinical perspectives for subjects with respiratory disorders
54

Expected Profiles and Temporal Stability of The LOOK

Baird, Sierra Marie 01 June 2015 (has links) (PDF)
The LOOK is an iOS based iPad app designed to measure viewing time as an estimate of sexual interest. Participants used a 7-point Likert scale to rate 154 images based on sexual attractiveness. The images belonged to 14 differentiated gender and age categories from infants to elderly adults. Before rating each image participants were asked to complete an additional task of locating and touching a small dot found in one of the four corners of the screen. This was included to make sure that participants we attending to each image, and to add another level of information to the results.The purpose of this study was to establish the expected reference group viewing time expected patterns and temporal stability using the LOOK, for nonpedophilic, exclusively heterosexual, college-age males and females. 56 male and 75 female undergraduate students from BYU psychology classes participated. The expected patterns were established and are similar to previously established sexual attraction patterns with slight difference due to the additional categories in the LOOK. The results are broken up into three different sections: dot time (the time from when the image appears to when the dot is touched), rate time (the time from when the dot is touched to when the image is rated), and total time (the combined dot and rate time). Results of the analysis indicate that dot time stability is 96.43% for males and 100% for females. Rate time stability is 64.29% for males, and 73.33% for females. And the total temporal stability is 98.21% for males and 100% for females.
55

Sex Dependence of the Respiratory Response During Sepsis

Clifford, Caitlyn 27 January 2023 (has links)
No description available.
56

Measurement of Agreement of Resting Metabolic Rate between Indirect Calorimetery and Multiple Estimation Models in Adults Using Air Displacement Plethysmography

Miller, Brian January 2013 (has links)
No description available.
57

The Role of AMP-Activated Protein Kinase (AMPK) in Hypoxic Chemotransduction by the Carotid Body

Jordan, Heidi Lynn 13 June 2012 (has links)
No description available.
58

Venous haemodynamic and cerebrospinal fluid anomalies associated with multiple sclerosis

Beggs, Clive Barron January 2014 (has links)
This critical synopsis of prior work by Clive Beggs is submitted in support of a PhD by published work. The work focuses on venous and cerebrospinal fluid (CSF) anomalies associated with multiple sclerosis (MS) and other neurological diseases. MS is characterized by focal inflammatory lesions, which are often venocentric. Recently a vascular syndrome, chronic cerebrospinal venous insufficiency (CCSVI) has been linked with MS. This syndrome, which is characterized by constricted cerebral venous outflow, has become mired in controversy, with various studies producing conflicting findings, with the result that the science associated with CCSVI has become obscured. Clive Beggs work seeks to bring clarity to the debate surrounding CCSVI by characterizing physiological changes associated with constricted cerebral venous outflow. The work submitted here involves collaborative studies with Robert Zivadinov (University of Buffalo), Paolo Zamboni (University of Ferrara), and Chih- Ping Chung (National Yang Ming University of Medicine). The key findings of these studies are: (i) MS patients, diagnosed with CCSVI, exhibit greatly increased hydraulic resistance of the cerebral venous drainage system; (ii) MS patients experience loss of the small cerebral veins; (iii) MS patients exhibit reduced CSF bulk flow, consistent with mild venous hypertension; (iv) MS patients exhibit increased CSF pulsatility in the Aqueduct of Sylvius, which appears to be linked with mild venous hypertension associated with CCSVI; and (v) jugular venous reflux is associated with white matter and parenchymal volumetric changes in Alzheimer’s patients. Collectively, these findings suggest that extracranial venous anomalies are associated with changes in the intracranial physiology.
59

Impact d’une alimentation maternelle riche en graisse et en sucre pendant les périodes de préconception, gestation et lactation sur la physiologie olfactive de la progéniture : étude expérimentale chez la souris / Impact of a high fat high sucrose maternal diet during preconception, gestation and lactation on progeny's olfactory physiology : experimental study in mice

Merle, Laëtitia 17 December 2018 (has links)
L’alimentation maternelle conditionne la santé métabolique et cardiovasculaire de la progéniture, mais l’impact sur les systèmes sensoriels reste peu étudié. L’olfaction joue un rôle comportemental crucial pour l’évitement des dangers et pour la prise alimentaire. Dès le plus jeune âge, les odeurs participent à l’établissement des préférences alimentaires, qui influencent les habitudes alimentaires de l’adulte. Le système olfactif repose sur le fonctionnement de neurones qui se développent pendant la vie embryonnaire, continuent leur maturation après la naissance et sont continuellement régénérés au cours de la vie. Ces neurones sont en permanence modulés par les facteurs métaboliques. Les patients atteints de troubles métaboliques ont plus de risques de présenter des altérations de la perception des odeurs, et l’exposition à une alimentation de type obésogène ou diabétogène induit des perturbations olfactives chez le rongeur.Le but de cette thèse était d’explorer les effets d’une exposition périnatale au gras et au sucre, à travers l’alimentation maternelle pendant les périodes de préconception, gestation et lactation, sur la physiologie olfactive de souris juvéniles.L’alimentation grasse et sucrée (high-fat high-sucrose, HFHS) a modifié la composition lipidique du lait maternel. La caractérisation métabolique des petits a révélé un surpoids, un excès de masse grasse épididymaire et une hyperleptinémie chez les petits provenant d'une mère sous alimentation HFHS. Les capacités olfactives évaluées lors d'un test de nourriture enfouie et par mesure du comportement de flairage induit par les odeurs étaient altérées chez les petits dont la mère a été exposée à l'alimentation HFHS. Cependant, nos résultats n’ont pas montré de modification de la sensibilité de l’épithélium olfactif (EO) ou de l’expression des gènes codant pour les éléments de la cascade de transduction olfactive. L’exploration du traitement central du signal olfactif a révélé un impact de l’alimentation maternelle HFHS sur le degré de ramification dendritique des interneurones du bulbe olfactif. En revanche, l’activation des neurones dans le cortex piriforme après une exposition odorante n’était pas modifiée.Ainsi, l'alimentation maternelle HFHS pendant les périodes de développement des petits induit chez les mâles des altérations de la perception olfactive, sans perturbation de la détection des odeurs par l'EO, mais associées à des modifications neuronales dans les structures olfactives centrales. La leptine, hormone métabolique connue pour son action sur l’olfaction et sur le développement neuronal, pourrait être à l’origine de ces déficits olfactifs. / The influence of maternal diet on progeny’s health has been thoroughly investigated regarding metabolic and cardiovascular diseases, but the impact on sensory systems remains unknown. Olfaction is of great behavioral importance for avoiding hazards and for feeding behavior. In childhood especially, olfaction participates in establishing food preferences, which partly determine adult eating habits. The olfactory system is made of sensory neurons that develop during the embryonic life, pursue their maturation after birth and are continuously regenerated over life. Olfactory neurons activity can be modulated by metabolic factors. Patients with metabolic disorders are at risk of impaired olfactory sensitivity. Adult mice exposed to an obesogenic or diabetogenic diet exhibit disrupted olfactory behavior.The aim of this thesis was to investigate the effect of a perinatal exposure to fat and sugar, through maternal diet during preconception, gestation and lactation, on the olfactory system of young mice.Maternal high fat high sugar (HFHS) diet modified milk lipids composition. When investigating pups’ metabolic phenotype, overweight, increased epididymal fat and hyperleptinemia were revealed in pup’s born from dams fed with the HFHS diet. Olfactory abilities were assessed in a buried food test and by measuring odor-induced sniffing behavior and were disrupted in the progeny of HFHS diet fed dams. However, olfactory epithelium sensitivity and gene expression of constituents of the olfactory transduction cascade were not affected by maternal HFHS diet. When investigating olfactory central processing, dendritic complexity of interneurons in the olfactory bulb was found to be affected by maternal HFHS diet. Meanwhile, neuronal activation in piriform cortex was not altered.These results show that maternal HFHS diet during pups’ development alters olfactory perception in male progeny, without impairing odor detection by the OE, and associated with neuronal modifications in olfactory central areas. Leptin is a metabolic hormone known to influence olfaction and neurons development which could have induced the olfactory defects.
60

Influência da composição da dieta na gordura intramiocelular, função endotelial e resistência à insulina, em mulheres jovens com sobrepeso metabolicamente saudáveis / High fat and high cab diet effects on intramyocellular lipids, endothelial function and insulin resistance in young metabolic healthy overweight women

Parente, Erika Bezerra 14 May 2009 (has links)
Dietas ricas em gordura ou carboidrato têm sido difundidas e consumidas nas últimas décadas, entretanto pouco é conhecido sobre as consequências metabólicas destas em longo prazo. Neste estudo, foram analisados a quantidade de gordura intramiocelular (IMCL), a função endotelial, além da lipemia, glicemia, insulinemia e resistência à insulina após semanas de dieta rica em gordura ou carboidrato, perdendo ou mantendo peso. De 43 mulheres triadas com sobrepeso (25< BMI <29.9 Kg/m2), 22 foram randomizadas para duas diferentes sequências de dietas. O IMCL foi medido através de espectroscopia por ressonância magnética 1H e a função endotelial pela pletismografia. Após 4 semanas de dieta rica em carboidrato, mantendo peso, foi observado aumento no IMCL do músculo tibial anterior (2.06 ± 1.27 vs. 3.52 ± 1.92, p=0.04) e na insulinemia em jejum (11.55 ± 4.43 vs. 14.03 ± 5.23, p=0.04), enquanto a dieta rica em gordura, no mesmo período, ocasionou aumento no HDL-C (37.06 ± 8.42 vs. 42.5 ± 9.32, p=0.003) e redução nos níveis de triglicerídeos em jejum (102,83 ± 34,10 vs. 75,83 ± 20,91, p=0,02). A função endotelial, colesterol total, LDL-C e resistência à insulina não mudaram durante esta fase. A perda de peso (média de 5%, por 8 semanas), não promoveu modificações nos parâmetros metabólicos vistos com a dieta de manutenção de peso. A partir destes resultados, concluiu-se que a ingestão de dieta rica em carboidrato, por 4 semanas de manutenção de peso, aumenta a insulinemia em jejum e o IMCL do músculo tibial anterior, enquanto a dieta rica em gordura pelo mesmo período aumenta o HDL-C e reduz triglicerídeos em mulheres saudáveis com sobrepeso. / High fat or high carbohydrate (cab) diet have been widely difunded and consumed during last decades; however it is not clear their metabolic effects in long term. In the present study we analyzed intramyocellular lipids (IMCL), endothelial function, plasma lipids, glucose, insulin and insulin resistance after high fat or high cab diet during weeks, maintaining or losing weight. 43 overweight women (25< BMI <29.9 Kg/m2) were screened, 22 of them were randomized to two different diet sequence. IMCL was measured by using 1H magnetic resonance spectroscopy and endothelial function by using plethysmography method. Tibialis anterior IMCL (2.06 ± 1.27 vs. 3.52 ± 1.92, p=0.04) and fasting insulinemia increased (11.55 ± 4.43 vs. 14.03 ± 5.23, p=0.04) after four weeks of high cab diet after maintenance phase, while fasting HDL-C increased (37.06 ± 8.42 vs. 42.5 ± 9.32, p=0.003) and triglycerides levels decreased (102.83 ± 34.10 vs. 75.83 ± 20.91, p=0.02) after maintenance phase of high fat diet. Endothelial function, total cholesterol, LDL-C and insulin resistance did not alter during maintenance phase. A weight loss of 5%, after eight weeks, did not promote changes in the metabolic parameters, as seen during maintenance phase. Based on these results, it was concluded that high cab diet, four weeks with no weight change, increases tibialis anterior IMCL and fasting insulinemia, while high fat diet during same period increases HDL-C and decreases triglycerides in a healthy overweight women population.

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