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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.
261

CORTISOL, PHYSICAL ACTIVITY, AND WEIGHT LOSS IN A RANDOMIZED CLINICAL TRIAL

Smith, Shawn S. 01 January 2014 (has links)
Abnormal cortisol levels may be an important factor in the ability of an individual to lose weight and maintain weight loss. This study examined overweight and obese individuals who participated in a weight loss program. Cortisol, physical activity, and weight loss were measured at regular intervals and examined for possible relationships
262

Mechanisms of Na+ Homeostasis by Zebrafish (Danio Rerio) in Acidic Water

Kumai, Yusuke 30 September 2013 (has links)
Zebrafish, Danio rerio, are able to survive exposure to extreme acidity (pH 4). Because previous studies demonstrated that disruption of ionic balance during exposure to acidic water is the major cause of mortality in acid-sensitive freshwater species, the focus of this thesis was to characterize the molecular mechanisms enabling zebrafish to maintain their Na+ homeostasis following exposure to acidic water. Initial findings (Chapter 2) demonstrated that branchial mRNA expression of selected isoforms of claudins, major components of tight junctions, are altered in an isoform-dependent manner, suggesting the potential regulation of epithelial permeability to minimize ion loss. Concurrently, a marked stimulation of Na+ uptake was observed in adults and larvae following acid-exposure. Because of the uniqueness of this response (increasing Na+ uptake in acidic water) among freshwater teleosts, the mechanisms related to Na+ uptake and its stimulation were investigated further (Chapters 3 - 7). Pharmacological treatments and gene knockdown approaches revealed that a functional metabolon consisting of an apically expressed Na+-H+-exchanger (NHE3b) in association with an apically expressed ammonia-conducting channel (Rhcg1), enables Na+ uptake in acidic water. During chronic (>1 day) exposure to acidic water, cortisol (via glucocorticoid receptors) and catecholamines (via β-adrenergic receptors) are involved in stimulating Na+ uptake. Although catecholamines may act on both NHE3b and Na+-Cl- co-transporter (NCC), the effects of cortisol on Na+ uptake are mediated primarily by activation of NHE3b. On the other hand, during acute (<3 h) exposure to acidic water, cortisol does not appear to affect Na+ uptake; rather, the stimulation of Na+ uptake appears to be mediated by angiotensin II and catecholamines. Cyclic AMP (cAMP), a signalling molecule synthesized following the activation of β-adrenergic receptors, is critically involved in stimulating Na+ uptake, likely via activation of NHE3b and NCC. In agreement with this idea, ionocytes that express NHE3b also express high levels of β-adrenergic receptor (propranolol binding sites) as well as trans-membrane adenylyl cyclase (forskolin binding sites). Taken together, the results of this thesis provide fresh insight into the mechanisms of osmoregulation in freshwater (FW) fish. In particular, the data reveal the presence of complex pathways regulating Na+ uptake in zebrafish exposed to acidic water. The relative importance of the various pathways depends in part on the duration of exposure; acute versus chronic.
263

Stress and metabolic responses to municipal wastewater effluent exposure in rainbow trout effluent

Ings, Jennifer Sophia January 2011 (has links)
Municipal wastewater effluent (MWWE) is an important source of pollution in the aquatic environment impacting fish. MWWE is a complex mixture of chemicals including pharmaceuticals, personal care products, industrial chemicals and pesticides. A link between reproductive endocrine disruption and MWWE exposure has been established in fish, but less is known about the effects of MWWE on non-reproductive endocrine disruption. The overall objective of this thesis was to examine the impacts of MWWE exposure on the stress response and intermediary metabolism in rainbow trout (Oncorhynchus mykiss). In fish, the primary adaptive organismal stress response involves the activation of hypothalamic-sympathetic-chromaffin axis to produce catecholamines, predominantly epinephrine, and the hypothalamic-pituitary-interrenal (HPI) axis to produce cortisol. Both of these hormones play a key role in elevating plasma glucose levels that is essential to fuel the increased energy demand associated with stress. Along with the organismal stress response, the cellular stress response, involving the synthesis of a suite of heat shock proteins (hsps), also plays an important role in protecting cellular protein homeostasis in response to stressors, including toxicants. The impact of MWWE on stress-related pathways were identified using a low-density trout cDNA microarray enriched with genes encoding for proteins involved in endocrine-, stress- and metabolism-related processes. This was further confirmed by assessing plasma hormone and metabolite levels and stress-related targeted genes and proteins expression and enzyme activities in select tissues in rainbow trout. Studies were carried out in controlled field (caging) and laboratory experiments to examine the impacts of MWWE on stress and tissue-specific metabolic responses in rainbow trout. Further in vitro studies using rainbow trout hepatocytes in primary cultures were carried out to investigate the mechanism of action of two pharmaceuticals, atenolol and venlafaxine, found in relatively high concentrations in MWWE in impacting the stress-mediated glucose response. In caged fish, MWWE exposure significantly elevated plasma cortisol and glucose concentrations, and altered the mRNA abundance of a number of stress-related genes, hormone receptors, glucose transporter 2 and genes related to immune function. When fish were exposed to an acute handling stress following a 14 d exposure to MWWE, the cortisol response was abolished and the glucose response was attenuated. The effects on cortisol did not correlate with changes in the expression of genes involved in cortisol biosynthesis, but were associated with an increase in hepatic glucocorticoid receptor (GR) protein expression. Upon further investigation in controlled laboratory studies, MWWE exposure elevated constitutive hsp 70 and hsp90 expression after 8 d exposure, which correlated with a decrease in glycogen levels in the liver in fish exposed to a high concentration of MWWE compared to control fish, pointing to a MWWE-induced increase in liver energy demand. By 14 d, glycogen stores were replenished, and this was commensurate with increases in liver gluconeogenic capacity, including increases in the activities of phosphoenolpyruvate carboxykinase (PEPCK) and alanine aminotransferase (AlaAT), along with a decrease in liver GR expression. In the heart, GR protein expression increased in treated fish, and the activity of pyruvate kinase increased, indicating an increase in glycolytic capacity. Subjecting the MWWE exposed fish to a secondary handling disturbance (acute stress) led to an attenuated plasma cortisol and glucose response compared to the control group. This corresponded with a reduced liver gluconeogenic capacity and a lower liver and heart glycolytic capacities, reflecting a disturbance in the energy substrate repartitioning that is essential to cope with stress. While it is difficult to establish causative agents from a complex mixture such as MWWE, the two pharmaceutical that were tested impacted glucose production. Specifically, atenolol and venlafaxine disrupted the epinephrine-induced glucose production, but did not modify cortisol-mediated glucose production in trout hepatocytes. The suppression of epinephrine-mediated glucose production by atenolol and venlafaxine was abolished by cAMP analogue (8-bromo cAMP) or glucagon (a metabolic hormone that increases glucose production). This suggests that both drugs disrupt β-adrenoceptor signaling, while it remains to be determined if the response is receptor isoform-specific. Altogether MWWE exposure disrupts the organismal and cellular stress responses in trout. Key targets for MWWE impact leading to the impaired cortisol and metabolic responses to stress include liver and heart GR expression, liver gluconeogenic capacity, and liver, heart and gill glycolytic capacities. Most significantly, MWWE impairs the ability to metabolically adjust to a secondary acute stressor, which is an important adaptive process that is integral to successful stress performance. From an environmental stand-point, long-term exposure to MWWE will lead to reduced fitness and will compromise the capacity of fish to cope with additional stressor, including escape from predators.
264

Stress Physiology of Bears: Cortisol Dynamics and Identification of Novel Serum Proteins

Chow, Brian Andrew January 2013 (has links)
There is a need to understand how free-ranging animals respond and adapt to stress. However, little is currently known regarding the physiologic adaptations to stress in bears, and there are few tools available to wildlife managers to assess the health and stress status of free-ranging animals, including ursids. The hypothalamus-pituitary-adrenal (HPA) axis plays major roles in the physiological adaptation to stress, leading to the increased secretion of glucocorticoids (e.g. cortisol in most mammals) that mediate adaptive changes in physiology and behaviour. The vast majority of glucocorticoids are bound to its primary carrier protein, corticosteroid-binding globulin (CBG), in most animals, and only the unbound fraction is bioavailable. Thus, CBG plays a major role in modulating glucocorticoid dynamics, and this protein must be characterized to build a more complete understanding of the adaptive role that the HPA axis plays in mitigating stress in bears. The overall objective of this thesis was to characterize the HPA axis activity and CBG levels in bears, and develop tools targeted towards the monitoring of the health and stress status of American black bear (Ursus americanus), grizzly bear (U. arctos), and polar bear (U. maritimus). The binding characteristics of cortisol to CBG in bears were studied via saturation binding experiments, and this information was used to estimate free cortisol concentrations based on CBG concentrations. To quantify CBG concentrations in bears, an enzyme-linked immunosorbent assay (ELISA) was developed. Grizzly bear CBG cDNA was cloned and sequenced, and an antibody was developed against a peptide sequence of the deduced amino acid sequence. The antibody showed good cross-reactivity against black, grizzly, and polar bear CBG, and the ELISA based on this antibody found differences in the mean CBG levels between species. Using this data, free cortisol levels were estimated, and mean levels were elevated in polar bears relative to black and grizzly bears. Having developed these tools, the roles that corticosteroid-binding globulin (CBG) and bioavailable cortisol played in the physiological adaptation to major life history traits and environmental challenges faced by ursids were investigated. Importantly, CBG was not modulated by the acute stress of capture and handling, despite the large differences in the magnitude of acute cortisol responses that are induced by these methods, suggesting that CBG levels may reflect the chronic health and stress status of bears. Altogether, there were few changes in CBG levels throughout much of the annual life cycle of bears, implying that CBG does not play a major adaptive role in the life history traits of bears and, instead, metabolic and environmental factors may be the key modulators of cortisol dynamics. However, CBG was not significantly associated with our measures of dietary patterns and nutrition, including body condition, seasonal dietary patterns, and fasting. The majority of the observed variation in the levels of this protein in bears remains unexplained. However, stress-induced free cortisol levels were negatively associated with urea to creatinine ratio (an indicator of dietary protein content and fasting status in grizzly and polar bears, respectively) and positively associated with lactation in hibernating black bears, suggesting that the variation in adrenal function may be playing an important role in the adaptation to adverse environmental conditions and/or metabolic stress in bears. In addition to serum cortisol dynamics, other proteins were also hypothesized to play adaptive roles in maintaining the hibernating phenotype in bears. Changes in the serum proteome during hibernation in black bears were assessed as a means to discover novel proteins that may be indicative of metabolic stress in bears. The serum proteomes of active and hibernating black bears were compared and analyzed for significant changes by two-dimensional electrophoresis and tandem mass spectrometry. Proteins involved with immune-related function were significantly altered during hibernation, leading to the proposal that the serum protein changes are essential for maintaining immune competence, wound healing, and bone structure. Altogether, this thesis developed a method to quantify CBG and estimated free cortisol concentrations in bears, and characterized their roles in the physiological adaptations associated with the major life history traits and environmental challenges faced by ursids. Also, novel serum proteins were identified as potential markers of immune function and health status in bears. These tools may be tremendously useful for wildlife managers and conservationists in determining how chronic stressors, including anthropogenic activities and climate change, may impact the stress and health performances of individual and populations of free-ranging bears.
265

Persistent fatigue and endocrine function in women after radiotherapy for breast cancer.

Short, Michala January 2010 (has links)
Doctor of Philosophy(PhD) / The experience of persistent fatigue after breast cancer treatment is estimated to affect approximately one in four women, but fatigue development and factors associated with cancer-related fatigue are poorly understood. Gaining a better understanding of these issues is important because persistent fatigue after radiation therapy can be a debilitating experience for cancer survivors. The objectives of this study were: (1) to determine fatigue prevalence in women with breast cancer at standardised timepoints after radiation therapy; (2) to investigate the relationships between fatigue, salivary cortisol rhythm and thyroid function; (3) to investigate the amount of radiation dose received by the thyroid gland in different radiation therapy treatment techniques; and (4) to investigate the relationship between irradiation of the thyroid, thyroid function and fatigue. Participants in this research were women diagnosed with non-metastatic breast cancer and all were referred for adjuvant radiation therapy treatment. One cohort of participants (n = 48) was assessed prior to the start of radiation therapy and then six months after treatment, and a second cohort (n = 15) was assessed at six months and then at 12 months after treatment. Behavioural assessments included questionnaires that measured the level of multidimensional fatigue (MFSI–SF), the degree of fatigue and depression symptoms (SPHERE–12), impact that fatigue had on participants’ functioning (FIS) and aspects of quality of life (EORTC QLQ–C30). Biological assessments included a three day measurement of salivary cortisol rhythm and an assessment of thyroid function (TSH, free T4 and free T3). Radiation doses to the thyroid gland were determined from participants’ treatment plans. Six months after completing adjuvant radiation therapy, women receiving treatment for breast cancer experienced significant improvements in emotional fatigue, role functioning and social functioning. High fatigue levels were prevalent in 29% of women at six months and 33% of women at 12 months after treatment, but newly developed fatigue that was not present before treatment was only found in 5% of participants. There were no significant changes in cortisol rhythm over time or between fatigued and non-fatigued participants; however, significant positive correlations were found between fatigue and morning cortisol. Regarding thyroid function, significant decreases in free T4 hormone levels were seen from six months to 12 months after radiation therapy with larger decreases in free T4 levels being related to higher fatigue. Radiation doses to the thyroid gland were significantly higher in participants who received treatment to the regional lymphatics with a supraclavicular fossa radiation field compared to participants who received localised treatment to the breast or chest wall only. In the former, changes in thyroid function were observed, as were relationships between mean radiation dose to the thyroid and thyroid function.
266

Resposta cortisolêmica e sensibilidade ao hormônio adrenocorticotrófico (ACTH) de jundiá (Rhamdia quelen) em exposição sub-letal a agrotóxicos

Cericato, Leonardo [UNESP] 18 May 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-05-18Bitstream added on 2014-06-13T19:40:15Z : No. of bitstreams: 1 cericato_l_dr_jabo.pdf: 310501 bytes, checksum: 917bfed91edc7c58d80704c91dc52a3f (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / A intensificação das práticas agrícolas e o aumento da produção geralmente dependem da aplicação de agrotóxicos, que podem direta ou indiretamente contaminar as fontes de água, córregos, açudes e lençóis freáticos. O peixe jundiá (Rhamdia quelen) é uma espécie da família Siluridae que ocorre no sul da América do Sul. Devido a sua prolificidade, robustez e bom ganho de peso, a espécie tem sido intensivamente estudada. A resposta ao estresse é uma reação do organismo a uma variedade de fatores adversos e compreende uma série de processos fisiológicos adaptativos coordenados pelo eixo hipotálamohipófise- interrenal (eixo HHI). O impacto de contaminantes sobre a síntese dos hormônios corticosteróides ainda é pouco conhecido para peixes tropicais. Estes hormônios possuem importante papel em processos fisiológicos como crescimento, metabolismo, balanço hidromineral, reprodução e sistema imune. Assim, qualquer impacto no seu eixo neuroendócrino pode afetar o desempenho do animal. O efeito deletério dos contaminantes sobre o eixo HHI pode ser classificado como interrupção endócrina. Neste caso, um peixe sob estresse tem significativamente reduzida sua capacidade de elevar o cortisol plasmático e, assim, fica fisiologicamente comprometido e não responde adequadamente aos estressores comuns em seu ambiente. Assim, este trabalho avaliou a resposta de estresse de jundiás quando expostos á cinco agrotóxicos, por meio da avaliação da resposta cortisolêmica a estressor padrão e pelo teste de sensibilidade ao hormônio adrenocorticotrófico (ACTH). Com os resultados obtidos pode-se perceber que, a exposição sub-letal ao metil-paration, atrazine+simazine e glifosato exercem um efeito deletério na resposta cortisolêmica a um estressor adicional em jundiá (Rhamdia quelen) e que em teste... / Exposure to agrichemicals can have deleterious effects on fish, such as disruption of the hypothalamus–pituitary–inter-renal axis (HPI) that could impair the ability of fish to respond to stressors. In this study, fingerlings of the teleost jundiá (Rhamdia quelen) were used to investigate the effects of the commonly used agrichemicals on the fish response to stress. Five agrichemicals were tested: the fungicide (tebuconazole), the insecticide (methyl-parathion), and the herbicide (atrazine, atrazine+simazine, and glyphosate). Control fishes were not exposed to agrichemicals and standard stressors. In treatments 2– 4, the fishes were exposed to sub-lethal concentrations (16.6%, 33.3%, and 50% of the LC50) of each agrichemical for 96 h, and at the end of this period, were subjected to an acute stress-handling stimulus by chasing them with a pen net. In treatments 5–7 (16.6%, 33.3%, and 50% of the LC50), the fishes were exposed to the same concentrations of the agrichemicals without stress stimulus. Treatment 8 consisted of jundiás not exposed to agrichemicals, but was subjected to an acute stress-handling stimulus. Jundiás exposed to methyl-parathion, atrazine+simazine, and glyphosate presented a decreased capacity in exhibiting an adequate response to cope with stress and in maintaining the homeostasis, with cortisol level lower than that in the control fish (P<0.01). In conclusion, the results of this study clearly demonstrate that the acute exposure to sub-lethal concentrations of methyl parathion, atrazine+simazine, and glyphosate exert a deleterious effect on the cortisol response to an additional acute stressor in the jundiá fingerlings.
267

Effects of sleep deprivation on immune function via cortisol and catecholamines

Kennedy, James Morgan 18 June 2016 (has links)
Sleep loss alters both the concentration and activity of various aspects of the immune system. These alterations lead to increased susceptibility to infection and the progression of pathologies such as insulin resistance and atherosclerosis. Two proposed mechanisms of this alteration in immune function are the changes in both cortisol and sympathetic nervous system activity that accompany sleep deprivation. This work reviewed literature that measured the effects of periods of sleep restriction upon both cortisol and catecholamine concentrations within human subjects. Furthermore, studies which measured the effects of sleep loss upon these hormone levels and the associated changes in immune parameters were included. This thesis asserts that there is no defined pattern in reference to alterations of cortisol levels as a result of sleep deprivation. Furthermore, more evidence must be collected before implementing cortisol as a main effector of sleep loss upon immune system function. This dissertation, although repeatedly noting increased levels of norepinephrine following periods of sleep restriction, similarly argues that more research must be completed in order to declare that altered catecholamine concentrations as a result of sleep loss is a mechanism for altered immune function.
268

Developmental regulation of mitochondrial function in ovine fetal skeletal muscle

Davies, Katie Louisa January 2018 (has links)
Skeletal muscle is a highly metabolically active tissue, both in the adult and the fetus. Mitochondria are essential in providing energy in the form of ATP from the oxidative metabolism of carbohydrates, fats and amino acids. Mitochondrial function is influenced by the abundance and activity of the complexes comprising the electron transfer system (ETS) and the balance between mitochondrial fusion and fission. Any factors which affect the development of skeletal muscle, and mitochondria in particular, may have an impact not only on neonatal health but also on the metabolic health of the adult offspring. However, the normal developmental profile of skeletal muscle mitochondrial function as the fetus prepares for the increased metabolic challenges associated with extrauterine life, is not well characterised. The hormones, cortisol and triiodothyronine (T3) are known to be crucial in the maturation of several physiological processes during late gestation. Further, their role in regulating adult metabolism is well-documented. However, whether they play a role in regulating fetal mitochondrial function is unknown. Using fetal sheep, the aims of this project were twofold: 1) to determine any changes in skeletal muscle mitochondrial function which occur over the last third of gestation and in the first two days of neonatal life and 2) to determine any regulatory roles of cortisol and T3 in these developmental changes. Mixed fibre-type skeletal muscle was collected from fetuses at 3 time points over late gestation and from newborn lambs. In addition, skeletal muscle samples were taken from fetuses which had been thyroidectomised (TX) and fetuses infused with either T3 or cortisol. Respirometry, enzyme assays, qRT-PCR and western blotting were carried out on the skeletal muscle samples in order to assess mitochondrial parameters. Mitochondrial activity, as measured by carbohydrate- and fat- stimulated ADP-coupled oxygen uptake, increased with age in a thyroid hormone dependent manner, rising predominantly postnatally. Mitochondrial density, abundance of ETS complexes I-IV and ATP-synthase and expression of the adenine nucleotide transferase 1 and mitofusin 2 were all positively influenced by age, with the natural prepartum rise being prevented in the thyroidectomised fetuses. However, T3 infusion alone was insufficient to raise any of these factors prematurely. Cortisol infusion resulted in an increase in some aspects of mitochondrial oxidative capacity in a muscle-specific manner. Overall, the data presented shows that there are developmental changes in skeletal muscle mitochondria during the perinatal period. They also suggest that these changes are regulated by both cortisol and thyroid hormones in preparation for birth, although neither hormone alone was sufficient to induce all the functional changes.
269

Cortisol e testosterona salivares como biomarcadores de estresse e recupera??o em atletas de corrida de aventura

Martins, Andr? Olimpio 23 March 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-04T12:30:36Z No. of bitstreams: 2 andre_olimpio_martins.pdf: 2403767 bytes, checksum: 4b49a301c8017ae8a0db22438d3dbb77 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-04T12:31:00Z (GMT) No. of bitstreams: 2 andre_olimpio_martins.pdf: 2403767 bytes, checksum: 4b49a301c8017ae8a0db22438d3dbb77 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-01-04T12:31:00Z (GMT). No. of bitstreams: 2 andre_olimpio_martins.pdf: 2403767 bytes, checksum: 4b49a301c8017ae8a0db22438d3dbb77 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2013 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / A Corrida de aventura ? uma competi??o praticada em contato com a natureza, na qual o competidor utiliza obst?culos naturais para a pr?tica de v?rias modalidades esportivas combinadas. O cortisol salivar (CT) pode ser utilizado como biomarcador do estresse e estados catab?licos. A concentra??o salivar de testosterona (TT) pode representar um marcador de estado anab?lico do, j? que seus efeitos fisiol?gicos est?o relacionados com o repara??o tecidual. A propor??o entre a atividade anab?lica/catab?lica pode ser dada pela an?lise da raz?o testosterona/cortisol (T/C). O objetivo deste trabalho foi quantificar as concentra??es de CT e TT de participantes de uma corrida de aventura, para determina??o do impacto fisiol?gico deste tipo de prova. O estresse e a recupera??o dos atletas foram inferidos pela an?lise da concentra??o de CT e TT e da T/C, 1 semana antes da competi??o (dia 1), 1 dia antes da competi??o (dia 2), no dia da competi??o (dia 3) e 1 dia ap?s a competi??o (dia 4). Frequ?ncia card?aca e VO2m?x foram registrados para avalia??o da intensidade de esfor?o da prova. As concentra??es de CT para o dia 2 e 3, n?o se elevaram em rela??o ?s concentra??es apresentadas no dia 1. Entretanto, no dia 4, as concentra??es de CT foram superiores em compara??o ?s concentra??es dos dias 1, 2 e 3. O ritmo TT normal foi observado nos 04 dias analisados e n?o foi observada varia??o nas concentra??es de TT. A raz?o T/C apresentou-se diminu?da no dia 4 em compara??o ao dia 1. Os resultados mostraram que a T/C apresentou-se reduzida em mais de 75% no dia 4. Conclus?es: 1. Corrida de aventura ? um evento multiesportivo de alta intensidade de esfor?o f?sico e desafia homeostase e alostase corporais; 2. O esfor?o do treinamento e da competi??o possivelmente mostrou-se desajustado ao preparo f?sico dos atletas analisados, j? que, o ritmo CT observado, tanto no per?odo pr?, quanto no p?s-competi??o, indicou estados de exaust?o e catabolismo intenso, respectivamente. Contudo, mais analises s?o necess?rias para compreender se o esfor?o da competicao foi realmente desajustado para o organismo do atleta ou se o esfor?o f?sico n?o foi intenso o suficiente para evocar uma resposta dos eixos end?crinos analisados. / Disserta??o (Mestrado) ? Programa Multic?ntrico de P?s-gradua??o em Ci?ncias Fisiol?gicas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT Adventure racing is a competition practiced in contact with nature where the competitor uses natural obstacles to practice various combined sports. The salivary cortisol (CT) can be used as a biomarker of stress and catabolic states. The concentration of salivary testosterone (TT) may represent a marker of anabolic status since its physiological effects are related tissue repair. The ratio of the anabolic activity/catabolic can be given by analysis of the testosterone/cortisol ratio (T/C). The aim of this study was to quantify the CT and TT concentrations of the participants of an adventure race to determine the physiological impact of such test. Stress and recovery of athletes were inferred by analyzing the TC and TT and T / C concentration of: 1 week before competition (day 1), 1 day before competition (day 2), competition day (day 3) and 1 day after competition (day 4). VO2max and heart rate were recorded to assess the intensity of effort of competition. The concentrations of CT to day 2 and 3 did not increase compared to the concentrations showed on day 1. However, on day 4, the TC concentrations were higher compared to concentrations on days 1, 2 and 3. The TT regular rhythm was observed in 04 days and there was no variation in the concentration of TT. The ratio T/C appeared reduced at day 4 compared to day 1. The results showed that T/C appeared reduced by more than 75% in 4 days. Conclusions: 1. Adventure Racing is a multisport event of high intensity physical exertion and challenges homeostasis and allostasis body; 2. The stress of training and competition possibility proved inadequate to the physical preparation of athletes analyzed, since, CT rhythm observed in both pre and post-competition showed states of exhaustion and intense catabolism, respectively. 3. However, more analyses is necessary to understand if the competition was wrong to the athletic`s organism or if the effort was not intense enough to stimulate an answer from the endocrine axis analyzed.
270

Avalia??o do efeito de uma sess?o de exerc?cio f?sico de intensidade leve a moderada sobre par?metros end?crino-metab?licos e de estresse oxidativo de pacientes submetidos ? hemodi?lise

Domingues, Talita Emanuela 06 November 2015 (has links)
Submitted by Alexandre Soares (alexandredesoares@yahoo.com.br) on 2016-07-19T13:19:35Z No. of bitstreams: 1 talita_emanuela_domingues.pdf: 1944980 bytes, checksum: c19178f686ffe12e73375417db38510c (MD5) / Rejected by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br), reason: Rever: Refer?ncia ABNT Tipo Nota de disserta??o/Tese Resumos Palavra Chave Ag?ncia Financiadora http://acervo.ufvjm.edu.br/jspui/handle/1/559 on 2016-07-21T15:25:51Z (GMT) / Submitted by Alexandre Soares (alexandredesoares@yahoo.com.br) on 2016-08-25T11:53:01Z No. of bitstreams: 1 talita_emanuela_domingues.pdf: 1944980 bytes, checksum: c19178f686ffe12e73375417db38510c (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-08-25T12:40:05Z (GMT) No. of bitstreams: 1 talita_emanuela_domingues.pdf: 1944980 bytes, checksum: c19178f686ffe12e73375417db38510c (MD5) / Made available in DSpace on 2016-08-25T12:40:05Z (GMT). No. of bitstreams: 1 talita_emanuela_domingues.pdf: 1944980 bytes, checksum: c19178f686ffe12e73375417db38510c (MD5) Previous issue date: 2015 / A doen?a renal cr?nica consiste em les?o renal com perda progressiva e irrevers?vel da fun??o dos rins. Nesta fase, os pacientes recebem indica??o de terapia renal substitutiva sendo a Hemodi?lise o recurso mais utilizado. Evid?ncias indicam que a pr?tica de exerc?cio f?sico intradial?tico ? ben?fica. Entretanto, os benef?cios desta modalidade de exerc?cio sobre par?metros end?crino-metab?licos e de estresse oxidativo ainda s?o poucos conhecidos. Objetivo: Avaliar o efeito de uma sess?o de exerc?cio f?sico de intensidade leve a moderada, sobre par?metros end?crino-metab?licos e de estresse oxidativo de pacientes com doen?a renal cr?nica submetidos ? hemodi?lise. M?todos: Doze volunt?rios, alocados de forma randomizada, do Servi?o de Hemodi?lise da Santa Casa de Caridade de Diamantina/MG participaram do estudo. Todos foram cross-over durante o experimento, a fim de comparar os resultados entre os dias de hemodi?lise sem exerc?cio (HD s/ exc) e hemodi?lise com exerc?cio (HD c/exc), e os dias posterior ? sess?o de hemodi?lise sem exerc?cio (P-HD s/ exc) e posterior ? sess?o de hemodi?lise com exerc?cio (P-HD c/exc), para cada volunt?rio. O exerc?cio f?sico intradial?tico ocorreu de maneira supervisionada, e por meio de um cicloerg?metro port?til. A coleta de saliva para avalia??o dos par?metros end?crino-meteb?licos cortisol e testosterona ocorreu durante todos os dias do protocolo experimental, em seis momentos ao longo do dia, a saber: ao acordar (T1) e trinta minutos ap?s (T2), 12:00h (T3), 14:00h (T4), 16:00h (T5) e ?s 19h (T6). As amostras de sangue para avalia??o dos par?metros de estresse oxidativo foram coletadas apenas em dias de hemodi?lise, em dois momentos: antes (T3) e ap?s (T4) a sess?o de hemodi?lise. Resultados: As concentra??es de cortisol e testosterona para os dias de hemodi?lise com exerc?cio f?sico (HD c/exc) n?o se elevaram significativamente em rela??o ?s concentra??es apresentadas no dia de hemodi?lise sem exerc?cio f?sico (HD s/exc), o que tamb?m ocorreu para os dias posteriores ? aplica??o do protocolo de exerc?cio intradial?tico (PHD c/ exc e P-HD s/ exc). Entretanto, a raz?o testosterona/cortisol aumentou significativamente no dia posterior ? sess?o de hemodi?lise com exerc?cio (P-HD c/ exc) quando comparada ao dia posterior ? sess?o de hemodi?lise sem exerc?cio (P-HD s/ exc). Os par?metros de estresse oxidativo n?o apresentaram altera??es induzidas pelo protocolo de exerc?cio f?sico. Conclus?o: O exerc?cio f?sico intradial?tico alterou o status anab?lico 24 horas ap?s ? sua realiza??o e n?o induziu altera??es significativas nos par?metros de estresse oxidativo.sumo / Programa Multic?ntrico de P?s-gradua??o em Ci?ncias Fisiol?gicas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / Chronic kidney disease is a kidney injury with progressive and irreversible loss of kidney function. At the severe stage, patients undergo renal replacement therapy and the hemodialysis being the most used medical resource. Evidence indicates that the practical of physical exercise during the hemodialysis sessions is beneficial. However, the benefits of this exercise modality on endocrine-metabolic parameters and on oxidative stress remains unknown. Objective: To evaluate the effect of an exercise session mild to moderate intensity, on endocrine-metabolic parameters and oxidative stress in patients with chronic renal failure undergoing hemodialysis. Methods: Twelve users of the Hemodialysis Service of Santa Casa de Diamantina Charity / MG participated, were assigned randomly as volunteers in the study and were cross-over during all the experiment in order to compare the results between the days of hemodialysis session without exercise (HD s/ exc) and hemodialysis session with exercise (HD c/ exc), and the subsequent days of hemodialysis session without exercise (P-HD s/ exc) and after the hemodialysis session with exercise (P-HD w / exc) for each volunteer. The exercise protocol was performed in a portable bicycle ergometer and its intensity was previously determined for each volunteer as mild to moderate. Saliva samples were collected during all days of the experimental protocol, six times throughout the day, namely on waking (T1) and thirty minutes after (T2), 12: 00 (T3), 14 : 00 (T4), 16: 00h (T5) and 19h (T6) to determine the salivary cortisol concentrations and salivary testosterone concentrations. Blood samples were collected in days of hemodialysis sessions, in two times: pre (T3) and after (T4) hemodialysis session to determine the REDOX status parameters. Results: The concentrations of cortisol and testosterone on the days of hemodialysis with exercise (HD c / exc ) did not increase significantly in relation to the concentrations shown on hemodialysis day without exercise (HD s / exc ), which also happened after the exercise protocol application days (P-HD c/ exc and PHD s/exc). However, the reason testosterone/cortisol increased significantly on the day after the hemodialysis session with exercise (P-HD w / exc) when compared to the day after the hemodialysis session without exercise (P-HD s / exc). The oxidative stress parameters did not show induced changes by the physical exercise protocol. Conclusion: It was shown that the exercise protocol induced changes in the anabolic status 24 hours after its realization and did not induce changes in oxidative stress parameters.

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