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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.
21

Autonomic Nervous System Adaptations to Physical Training in Congestive Heart Failure

Bentley, Todd 09 1900 (has links)
The purpose of this investigation was to examine the potential differences in autonomic nervous system adaptations, as assessed by heart rate variability techniques, between a group of stabilized CHF patients randomized to either a training group (aerobic+resistance) or a control group (usual care). In a single-blind, randomized controlled trial of 3-months of supervised exercise training and a further 3-months of home-based exercise, 28 stabilized CHF patients (NYHA 1-111) were randomized to either a training (AERWT) (n=16;11M,5F; age, 64.9±2.3; LVEF, 29.4±1.7%) or usual care (UC) (n=12; 10M,2F; age, 58.0±2.8; LVEF, 24.4±2.0%) group. Upon completion of the supervised exercise program, the AERWT group increased peak oxygen uptake (V02) (13.2±0.5 to 15.5±0.84 ml/kg/min, p<0.05), and single-arm curl scores (16.2±2.8 to 19.2±3.3 kg, p<0.05) significantly compared to the UC group, without any deleterious effect upon clinical status or left-ventricular function (LVEF: 31.3±1.7 to 33.2±1.9%, p=0.99). Physical training reduced expired ventilation and carbon dioxide based on successive workloads during symptom-limited incremental cycle ergometry in the AERWT group; however, this was found to be non-significant, in addition to changes in resting heart rate, anaerobic threshold, maximal exercise duration, maximal power output, and double product following training. Supine, resting power spectral indices remained unchanged from baseline to 6-months in both groups, as did the recovery of power spectral indices during supine rest following a symptom-limited incremental cycle ergometry test. A qualitative comparison of the power spectral changes from supine to standing revealed no significant differences between groups with respect to improvements in the baroreceptor response to orthostatic stress. Time domain parameters, derived from 24-hour ambulatory bolter monitoring, were also obtained at baseline, 3-months, and 6-months. The indices believed to be largely representative of vagal modulation, SDNN-Index, r-MSSD, and pNN50, tended to increase in the AERWT group with increased participation in the training program; however, the results did not obtain statistical significance (p=0.07). In addition, there were no significant changes in mean 24-hour heart rate or NN-interval, SDNN, or SDANN in the AERWT group (p=0.21). The present investigation revealed some evidence to suggest that exercise training in selected populations of CHF patients results in favourable changes in vagal modulation and baroreceptor sensitivity; however, unlike Coats et al. (1992), the present investigation failed to note any significant alterations in HRV frequency domain indices as a result of exercise training despite identical improvements in peak V02. The lack of significant findings in both the frequency and time domain HRV data could indicate that the autonomic dysfunction is so widespread and rampant in CHF that we cannot induce alterations through training as would be demonstrated in normal, healthy controls. In effect, these findings reinforce the hypothesis that in CHF the heart is the 'slave' of the periphery, and that due to the progressive lack of neural control of both the heart and circulation, in addition to an impairment in pump function, that the only effective means of improving physiological variables is through changes at the peripheral level. / Thesis / Master of Science (MS)
22

Postoje studentů středních škol k tělesné výchově v okrese České Budějovice \\ / Approach of the sedondary school students to the Physical Training in the district of České Budějovice

ŠIMKOVÁ, Lucie January 2009 (has links)
By using indirect method of analyzing standard questionnaire, we can assess the approach of the students to the Physical Training. The DIPO-J questionnaire was used at secondary schools in disctrict of České Budějovice. The questionnaire consists of sixty questions dividend into six dimensions according to the approaches. A particular numer of points is assigned to each reply. Then we can compare the results among the surveyed schools according to the sex and also these results can be compared to the previous thesis on the same theme. The questionnaire is focused on students` approach to the Physical Training as a required subject at secondary shools. These approaches reflect the Physical Training teachers as a object and subject of the education process. We can view from the obtained results the current situation of the Physical Training education and we can consider if there is need to change it.
23

Fotbollsledare om styrketräning för barn : – når forskning ut?

Fröberg, Andreas January 2011 (has links)
Fysisk träning för barn har alltid varit ett kontroversiellt ämne som berör såväl etiska och fysiologiska som medicinska frågor. Styrketräning är den form av träning som ställer dessa frågor på sin spets. De svenska officiella organen Idrottens Forskningsråd (IFR) och Riksidrottsförbundet (RF) har genom åren lagt fram rekommendationer och riktlinjer som ska fungera som underlag vid utformning av den träningsverksamhet som bedrivs i idrottens föreningsliv. Eftersom forskningsrön har förändrats i takt med forskningsframsteg har också rekommendationer och riktlinjer från officiellt håll varierat över tid. Syftet med föreliggande studie var att undersöka om fotbollsledare har kännedom om de senaste rekommendationerna vad gäller styrketräning för barn. I studien inkluderades fotbollsledare (n=39) som tränade pojkar i årskullarna 1998-2002. Med utgångspunkt i nya svenska rekommendationer om styrketräning för barn formulerades påståenden i en enkät. Med hjälp av enkäten samlades data in som kodades om till siffror och analyserades. I resultatet identifierades två variabler som hade betydelse för de åsikter som fördes fram i enkäten. Dessa variabler innebar att det för resultatet spelade roll i vilken division som fotbollsledarens fotbollsförening spelade i samt hur många år denne varit aktiv som fotbollsledare. Resultatet visade att fotbollsledare inte hade kännedom om de senaste rekommendationerna vad gäller styrketräning för barn. / Physical training for children has always been a controversial topic that raises ethical, physiological and medical issues. Although the recently revealed scientific evidence indicates that strength training can lead to a number of positive effects on children, there has always been a problem associated with weight training impact on child development. For several years the Swedish Sports Research Counsil (Idrottens Forskningsråd) and the Swedish Sports Confederation (Riksidrottsförbundet) has presented recommendations and guidelines that will serve as the basis for the design of training activities in sport clubs. Since research findings have changed over the past years, recommendations and guidelines from the Swedish Sports Research Counsil and the Swedish Sports Confederation has varied over time as well. The purpose of this study was to investigate whether football[1]leaders are aware of the latest recommendations regarding strength training for children. This study includes football leaders (n=39) who trains boys in age groups from 1998 to 2002. By using a questionnaire data was collected, coded and analyzed. The results of this study indicate that football leaders are not aware of the latest recommendations regarding strength training for children. [1]In US it is referred to as soccer.
24

The development of a personal training programme based on the principles of flow

Berzack, Anthony 12 1900 (has links)
Thesis (M Sport Sc (Sport Science))--University of Stellenbosch, 2006. / The motivation for this research evolved from a study of Flow in Sport (Jackson & Csikszentmihalyi, 1999). Flow is described as a state of optimal experience that could be attained by becoming immersed in a challenging task that absorbs all the attention on the task at hand. Physical exercise was used in this study because it provides a flow-conducive environment in which challenges can easily be gauged and increased, giving essential motivational feedback. A broad spectrum of sport psychology and flow-related research was applied in the design of a comprehensive and easily accessible system of understanding what it means to experience flow. Research that relates to the use of visualisation, relaxation and the use of natural triggers are key factors used in the implementation of the programme. The concept of flow was founded in seven fundamental elements that need to be present in order to experience flow. The programme was developed during several phases of sample testing over a period of two years to refine and condense the system so it would not detract attention from the task at hand. The final seven-week programme was presented to a sample of seven participants on a one-on-one basis. A combination of quantitative (measurements of performance levels in the chosen activity taken before and after the intervention programme intervention and qualitative (participants’ comments which were written down in terms of personal experiences related to the programme after completing the programme) methods were used to assess the effectiveness of the devised programme. Ground Evaluation Theory is described by Patton (1980) as the systematic working out of hypotheses and concepts during the course of research. This was a central feature of the nature of the development of the present programme. Patton (1980) describes a meta-evaluation as an evaluation of an evaluation. This was applied over the two-year period while refining and simplifying the present intervention so as to reduce potentially distracting analysis by participants. Using a standardised protocol, participants made use of personal past optimal experiences that epitomise each of the fundamental aspects of being in flow. These experiences (or blueprints) were then associated with natural triggers formed by seven segments of the human body to subconsciously refresh and enhance access to these past optimal states. A flow-chart on which these images were drawn was designed. It was used in conjunction with relaxation and visualisation to continually re-visit, refresh and apply these states of mind to reaching new peaks. Subjects were to visualise themselves immersed in performance of their task at the level set as the goal for the end of the programme. The past blueprinted states were used to recreate an optimal mental approach during this visualised performance. The goals were broken down into achievable challenging steps of progression with the use of personal training programmes designed by a sports scientist to be effective for attaining goals which were set. The flow-programme was evaluated in terms of setting training schedules, taking measurements and setting goals before intervention and then gauging the progress of these factors after the implementation of the programme. The factors measured were: the level of flow experienced in the chosen activity; satisfaction with life; adherence to the programme; and achievement of training goals. These variables were measured by comparing results in standardised tests which have proven reliable for measuring flow and satisfaction with life. Adherence to the programme was measured relative to the amount of training that had been specified in the programme designs. The attainment of goals was also measured by the percentage of goals that had been achieved, compared with those set by each participant for the programme.The results show that the subjects benefited from the programme on the four measures. The subjects also commented that they found the programme to be a highly effective tool for grasping an understanding of the concept of flow, as well as experiencing this elusive state. It was concluded that flow could be tapped into at a volitional level by using the devised intervention.
25

Fysisk aktivitet för patienter med hjärtsvikt – ur ett livskvalitetsperspektiv : En kvantitativ litteraturöversikt / Physical activity and quality of life in patients with heart failure

Olofsgård, Anna, Lindén, Sandra January 2017 (has links)
Cirka 200 000 personer i Sverige lever med hjärtsvikt. Tidiga symtom är andfåddhet, trötthet och mindre ork i vardagen. Oro, sömnsvårigheter och depression drabbar ofta patienten när sjukdomen förvärras, med sämre livskvalitet som följd. Det finns en korrelation mellan upplevelsen av fysiska begränsningar och upplevd livskvalitet. Många patienter med hjärtsvikt undviker att träna på grund av osäkerhet. Sjuksköterskans roll är att förmedla kunskap om fysisk aktivitet för att göra patienten trygg. Det är också viktigt att kunna identifiera en lämplig nivå och form på träningen, som ska vara individanpassad. Syftet med litteraturöversikten var att beskriva vilka effekter fysisk aktivitet har på livskvaliteten för patienter med hjärtsvikt. 16 kvantitativa artiklar valdes ut och analyserades. Resultatet visar att det finns god vetenskaplig evidens för att fysisk träning påverkar livskvaliteten positivt hos patienter med hjärtsvikt. Graden av deltagande har större betydelse för effekten än typen av träning. Övervakad träning har visat sig öka deltagandet, liksom social gemenskap. Genom att sjuksköterskan förmedlar individanpassad information och lyckas identifiera en träningsform som passar patientens intressen, resurser och behov ökar chansen till högt deltagande i fysisk aktivitet, vilket i sin tur kan leda till förbättrad livskvalitet. / Approximately 200 000 persons in Sweden are living with heart failure. Early symptoms are dyspnea, fatigue and difficulties in daily activities due to lack of energy. As the heart failure proceeds the patients are often facing anxiety, sleep deprivation and depression. Perceived physical limitations has shown to correlate well with perceived quality of life. Many patients with heart failure avoids physical activity due to feelings of uncertainty. The role of the nurse is to make the patient feel comfortable and safe to engage in physical training, by providing knowledge. It is important to identify a suitable level and form of individually tailored training. The purpose of the literary review was to describe how various forms of physical activities affects quality of life in patients with heart failure. 16 quantitative articles were chosen and analyzed. The result shows that physical training affects quality of life in a positive manner in heart failure patients. Level of participation is of greater importance than the form of training. Supervised training has shown to increase participation, as well as social interaction. By providing individually adjusted information and by identifying a form of training suitable to the patient, the nurse is able to influence the patient towards an increased engagement in physical activities, presumably leading to improved quality of life.
26

Efeito do treinamento com diferentes intensidades do exercício \"hang power clean\" no desempenho motor e na potência muscular de jogadoras de handebol / Effects of hang power clean training with different intensities on motor performance and muscular power of handball players

Silva, Claudio Machado Pinto e 20 February 2019 (has links)
O desenvolvimento da potência muscular e das habilidades motoras como salto vertical, velocidade de corrida e agilidade é fundamental para um bom desempenho nas modalidades esportivas coletivas, dentre elas o handebol. Os exercícios do levantamento de peso olímpico (LPO), dentre eles o hang power clean (HPC), têm sido comumente utilizados para esta finalidade; porém, pouco se sabe a respeito do efeito de diferentes intensidades de treinamento com o HPC sobre o desempenho motor de atletas. Desta forma, o objetivo do estudo foi investigar o efeito de dois protocolos de treinamento com 50% e 90% 1RM no exercício HPC nos ganhos de potência muscular dos membros inferiores, na altura do salto vertical, na velocidade de corrida, na mudança de direção e na força dinâmica máxima de jogadoras de handebol. Dezesseis atletas das categorias júnior e adulto foram divididas em dois grupos (LPO50 e LPO90; 50% e 90% 1RM, respectivamente) e submetidas a 15 sessões de treinamento durante sete semanas. Testes de potência muscular dos membros inferiores, altura do salto vertical sem e com contra-movimento (SJ e CMJ, respectivamente), velocidade de corrida, mudança de direção e força dinâmica máxima (1RM) nos exercícios meio-agachamento e HPC foram realizados pré- e pós-treinamento. Após o período de treinamento foi observado aumento significante da potência de membros inferiores no CMJ com 40% da massa corporal (MC) somente para o grupo LPO90, enquanto nenhuma alteração significante ocorreu no CMJ 60% e 80% MC para ambos os grupos. Não foram observadas alterações significantes na altura dos saltos verticais (SJ, CMJ e CMJ com diferentes sobrecargas externas) para os dois grupos; porém, a velocidade de corrida nas distâncias 0-5, 0-20 e 0-30m aumentou de forma significante e semelhante entre LPO50 e LPO90. Houve diminuição significante no desempenho da mudança de direção no teste T-40 para ambos os grupos. A 1RM no exercício HPC aumentou para os dois grupos enquanto nenhuma alteração significante foi observada para o exercício meio-agachamento. Assim, após 15 sessões de treinamento com HPC em diferentes intensidades (50% vs. 90% 1RM), pode-se afirmar que a utilização de menores intensidades promoveu adaptações positivas muito similares à utilização de maiores intensidades na velocidade de corrida e na força dinâmica máxima no exercício HPC, em jogadoras de handebol / The development of muscle power and motor skills such as vertical jump, running speed and agility is fundamental for a good performance in several team sports, among them handball. Olympic weightlifting (OWL) exercises such as the hang power clean (HPC) have been commonly used for this purpose; however, little is known about the effect of different training intensities with HPC on athletes\' motor performance. Thus, the objective of the study was to investigate the effect of two training protocols with 50% and 90% 1RM of the HPC exercise on lower limbs muscle power, vertical jump height, running speed, agility, and maximum dynamic strength of female handball players. Sixteen junior and adult athletes were divided into two groups (OWL50 and OWL90, 50% and 90% 1RM, respectively) and underwent 15 training sessions for seven weeks. Test for lower limbs muscle power, squat jump and countermovement jump height (SJ and CMJ, respectively), running velocity, agility, and maximal dynamic strength (1RM) in half-squat and HPC exercises were performed pre- and post-training. After the training period, a significant increase in lower limbs power in the CMJ was observed with 40% of body mass (BM) only for the OWL90 group, while no significant alteration occurred in the CMJ 60% and 80% BM for both groups. No significant changes were observed in vertical jumps height (SJ, CMJ and CMJ with different external loads) for both groups; however, running speed at 0-5, 0-20 and 0-30m increased significantly and similarly between OWL50 and OWL90. There was a significant decrease in agility performance for both groups. The 1RM in the HPC exercise increased for both groups while no significant change was observed for the half-squat exercise. Thus, after 15 training sessions with HPC at different intensities (50% vs. 90% 1RM), it can be stated that the use of lower intensities promoted positive adaptations in running speed and maximum dynamic strength in the HPC exercise similar to the use of higher intensities, in handball players
27

Ajustes da atividade simpática periférica promovidos pelo treinamento aeróbio em normotensos e hipertensos: efeitos da remoção seletiva dos barorreceptores arteriais. / Training-induced adjustments of peripheral sympathetic activity in normotensive and hypertensive rats: effects of sinoaortic denervation.

Burgi, Katia 21 March 2012 (has links)
No presente trabalho investigamos em ratos hipertensos espontâneos (SHR) e seus controles normotensos (WKY) os efeitos do treinamento físico sobre a atividade simpática a diferentes territórios, bem como os efeitos da remoção seletiva dos baroreceptores arteriais sobre a atividade simpática. SHR e WKY foram submetidos à desnervação sino-aórtica (SAD) ou cirurgia fictícia (SHAM) e alocados aos grupos T (50-60% da capacidade máxima, 1 hora/dia, 5 dias/semana) ou mantidos sedentários (S) por 3 meses.Nossos dados demonstraram que as adaptações induzidas pelo T no simpático periférico são tecido-específicos e dependem da linhagem experimental: redução do simpático ao coração e rins de WKY e SHR, com redução da atividade simpática ao músculo esquelético nos WKY treinados, mas aumentado nos SHR treinados, os quais apresentam simultaneamente extenso remodelamento vascular. Nossos dados demonstraram ainda, que as adaptações do simpático induzidas pelo T dependem da integridade dos baroreceptores arteriais. / In the present study we investigate in spontaneous hypertensive rats (SHR) and their normotensive controls (WKY) the effects of exercise training on sympathetic activity to different territories and the effects of the selective removal of arterial baroreceptors on sympathetic activity. SHR and WKY were subjected to sinoaortic denervation (SAD) or sham surgery (SHAM) and submitted to T (50-60% of maximum capacity, 1 hour / day, 5 days/week) or kept sedentary (S) for 3 months.Our data demonstrated that T-induced changes in peripheral sympathetic innervations are tissue-specific and depend on the experimental strain: reduced sympathetic to the heart and kidneys in WKY and SHR strains, and reduced sympathetic activity to the skeletal muscles in the trained WKY, but increased sympathetic activity in the trained SHR, which showed a simultaneous extensive vascular remodeling after training. Our results also demonstrated that training-induced sympathetic adaptations depend on the integrity of the arterial baroreceptors.
28

Seleção de microRNA e proteína alvo envolvidos com a função cardíaca de ratos infartados em resposta ao treinamento aeróbico / Selection of microRNA and target protein involved in cardiac function in infarcted rats in response to aerobic training

Melo, Stéphano Freitas Soares 11 April 2014 (has links)
O infarto do miocárdio (IM) é uma patologia causada pela obstrução parcial ou total das artérias coronárias responsáveis pela irrigação do miocárdio. Sabe-se que logo após o IM, o treinamento físico (TF) promove melhora e adaptações benéficas ao sistema cardiovascular. O objetivo do presente estudo foi traçar o perfil de microRNAs na área remanescente ao IM de ratos submetidos ou não ao TF através da técnica de microarray, selecionar e confirmar a expressão de um microRNA específico, por programas de bioinformática que tenha alvos que possam estar envolvidos com a melhora da função cardíaca com o TF. Também foi objetivo deste estudo, verificar a expressão do microRNA-1, do microRNA-29 e do microRNA-214 e dos respectivos alvos destes microRNAs, como o colágeno, NCX e SERCA2a. Para isso, ratos Wistar foram divididos em quatro grupos: SEDENTÁRIO SHAM (SED-SHAM), SEDENTÁRIO INFARTADO (SED-IM), TREINADO SHAM (TR-SHAM) e TREINADO INFARTADO (TR-IM). A função ventricular foi acompanhada com ecocardiografia antes e após oito semanas do protocolo de TF de natação. Os animais foram sacrificados, o RNA foi extraído e posteriormente foi traçado o perfil de microRNAs. Para seleção dos microRNAs foram estipulados dois padrões de expressão entre os grupos. De acordo com os critérios aplicados foram observados, apenas 6 microRNAs para o primeiro padrão de expressão e 3 microRNAs para o segundo padrão de expressão que satisfizeram todos os critérios. O microRNA-339-5p foi escolhido por apresentar expressão diferencial pronunciada como efeito do TF por ter dois genes (alvos selecionados por programas de bioinformática TargetScan, Miranda e PicTar), o Myo1c e o PGC-1 ?, que estão envolvidos com a regulação da função cardíaca. Neste estudo, foi possível verificar que nos grupos TR-SHAM e TR-IM ocorreu aumento da expressão da Myo1c e redução da expressão do microRNA-339-5p. Nossos resultados também mostraram que o TF induziu aumento na expressão dos microRNAs-29a/c, o que está relacionado com significativa diminuição na expressão gênica do COLIAI, COLIIIAI, diminuição na concentração de hidroxiprolina e fração volumétrica de colágeno de ratos com IM. Outro resultado deste estudo é que o TF induziu diminuição na expressão dos microRNAs-1 e 214, o que está relacionado com aumento na expressão protéica dos alvos SERCA-2a e NCX de ratos com IM. Esses efeitos estão associados com a melhora da função ventricular avaliada pela FEAT% (função sistólica) e pela relação E/A (função diastólica), realizado por avaliação ecocardiográfica após o período de TF. / Myocardial infarction (MI) is a disease caused by partial or total blockage of the myocardial coronary arteries. It is known that after MI, physical training (PT) improves and promotes beneficial adaptations to the cardiovascular system. The aim of this study was to analyse the microRNAs profile in the remaining area to MI in rats submitted to PT by microarray and select a specific microRNA by bioinformatics software that has targets involved with the improvement of cardiac function by PT. Also, the aim of this study was to verify the expression of the microRNA-1, microRNA-29 and microRNA-214 and its targets, such as collagen, NCX and SERCA2a. For this, rats were divided into four groups: SEDENTARY SHAM (SHAM - SED), INFARCTED SEDENTARY (SED-MI), TRAINED SHAM (TR-SHAM) and INFARCTED TRAINED (TR-IM). Ventricular function was monitored with echocardiography before and after eight weeks of the PT. The animals were sacrificed, the RNA was extracted and traced the profile of microRNAs. For selection of microRNAs were stipulated two patterns of expression between the groups. The first standard, 6 microRNAs were selected and in the second standard, 3 microRNAs were selected to satisfy all criteria. The microRNA- 339-5p was chosen because of pronounced differential expression with PT and have two target genes selected by bioinformatics programs (TargetScan, Miranda and PicTar) Myo1c and the PGC-1 ? are involved in the regulation of cardiac function. In this study, we found that the SHAM group and the group with MI undergoing PT increased expression of Myo1c in contrast to a decreased expression of microRNA-339- 5p. Our results also showed that PT induced increased expression of microRNA-29a/c, which is associated with a significant decrease in gene expression of COLIAI, COLIIIAI, the hydroxyproline xvii concentration and collagen volume fraction of rats with MI. Another result of this study is that the PT induced decrease in the expression of microRNA-1 and microRNA-214, which is related to the increase in protein expression of the targets SERCA-2a and NCX of rats with MI. These effects are associated with improved ventricular function assessed by FEAT % (systolic function) and E/A ratio (diastolic function), performed by echocardiography after the period of PT
29

Efeito do treinamento físico aeróbico sobre a expressão de myomiRs circulante e muscular em modelos experimentais de câncer / Effect of aerobic physical training on the expression of circulating and muscular myomiRs in experimental models of cancer

Gomes, João Lucas Penteado 25 September 2017 (has links)
Câncer é o nome que se designa para um conjunto de mais de 100 doenças. As células cancerosas acumulam mutações e apresentam uma alta velocidade de divisão celular, dessa forma, o câncer tem um caráter progressivo e degenerativo; sendo um problema de saúde pública mundial (INCA, 2017). Existem diversas comorbidades associadas ao câncer que levam a maior índice de mortalidade e ao agravamento da doença, uma destas é a caquexia. Os microRNAs são uma classe de moléculas que tem sido altamente investigada por estar relacionada com diversos fatores fisiológicos e também patológicos (AMBROS, 2001). Sabe-se que diversos microRNAs tem expressão alterada em indivíduos com câncer. Essas alterações na expressão dos microRNAs são encontradas na circulação sanguínea, no tumor e em alguns tecidos, como o muscular esquelético e cardíaco (CHEN et al., 2014). Por outro lado, o exercício físico aeróbico provoca profundas adaptações músculo esquelético, inclusive em condições patológicas. Uma das mais marcantes é a normalização do equilíbrio entre a síntese e a degradação de proteínas no miócito esquelético (CUNHA et al, 2012). O exercício físico aeróbico tem um papel importante na regulação da expressão de diversos microRNAs. Ainda, apresenta potencial terapêutico para restaurar a expressão de diversos microRNAs alterados presentes em diferentes doenças (FERNANDES et al., 2011). Neste trabalho analisamos a expressão de microRNAs enriquecidos no músculo esquelético (myomiRs) utilizando dois modelos MMTV-PyMT (câncer de mama, não caquético) e CT26 (câncer de cólon, caquético). Esses animais foram divididos em grupos sedentários e treinados e os controles eram animais saudáveis também divididos em sedentários e treinados. Observamos que os animais do modelo MMTV não apresentaram perda da função e massa muscular, entretanto dois myomiRs, miR-206 e 486, tem a expressão alterada no músculo esquelético e na circulação em função do câncer e o exercício físico não influencia na expressão dos mesmos. Ainda avaliamos os mesmos parâmetros no modelo CT26; A expressão dos myomiRs-206 e 486 também está alterada na circulação e no musculo esquelético e o exercício físico não influencia a expressão destes microRNAs. Nesse modelo a expressão da proteína PI3K está diminuída e de PTEN está aumentada em função do câncer. Nossos resultados indicam que os microRNAs 206 e 486 tem a expressão alterada no tecido muscular e na circulação em decorrência do câncer, independente da caquexia, e, podem ser marcadores de prejuízos nas vias de síntese proteica no tecido muscular / Cancer is the name designated for a set of more than 100 diseases. Cancer cells can be very aggressive, uncontrollable and with a high rate of cell division, so cancer has a progressive and degenerative nature and is a problem of global public health (INCA, 2017). There are several comorbidities associated with cancer that lead to higher mortality and worsening of the disease, one of which is cachexia. MicroRNAs are a class of molecules that has been highly investigated for being related to several physiological and also pathological factors (AMBROS, 2001). It is known that several microRNAs have altered expression in individuals with cancer. These changes in the expression of microRNAs are found in the bloodstream, tumor and in some tissues, such as skeletal and cardiac muscle. (CHEN et al., 2014). On the other hand, aerobic physical exercise causes profound skeletal adaptations, including in pathological conditions. One of the most striking is the normalization of the balance between synthesis and protein degradation in the skeletal myocyte (CUNHA et al, 2012). Aerobic physical exercise plays an important role in the regulation of the expression of several microRNAs. It has therapeutic potential to restore the expression of several altered microRNAs present in different diseases (FERNANDES et al., 2011). In our study we analyzed the expression of microRNAs enriched in skeletal muscle (myomiRs) using two models MMTV-PyMT (breast cancer, non-cachectic) and CT26 (colon cancer, cachectic). These animals were divided into sedentary and trained groups and controls were healthy animals also divided into sedentary and trained. We observed that MMTV animals showed no loss of function and muscle mass, however, two myomiRs, miR-206 and 486, have altered expression in skeletal muscle and circulation as a function of cancer, and physical exercise does not influence their expression. We also evaluated the same parameters in the CT26 model; The expression of myomiRs-206 and 486 is also altered in the circulation and skeletal muscle, and physical exercise does not influence the expression of these microRNAs. In this model the expression of PI3K protein is decreased and PTEN is increased as a function of cancer. Our results indicate that microRNAs 206 and 486 have altered expression in muscle tissue and circulation due to cancer, independent of cachexia, and may be markers of damage in the pathways of protein synthesis in muscle tissue
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Efeitos do treinamento físico sobre o metabolismo lipídico no fígado de ratos com caquexia associada ao câncer: papel do PPAR<font face=\"Symbol\">&#945;. / Effects of physical training exercise upon liver lipid metabolism of tumour-bearing rats: role of PPAR<font face=\"Symbol\">&#945;.

Carnevali Junior, Luiz Carlos 28 November 2011 (has links)
A caquexia é uma síndrome paraneoplásica caracterizada pelo comprometimento do metabolismo lipídico levando à marcadas alterações fisiológicas no fígado, entre estas o desenvolvimento de esteatose. O treinamento conhecidamente melhora a capacidade metabólica do fígado. O presente projeto verificou os efeitos do treinamento em ratos com caquexia induzida pelo tumor. Ratos Wistar machos foram divididos nos seguintes grupos: ratos sedentários controle (SC), sedentários portadores de tumor (ST), treinados controle (TC) e treinados portadores de tumor controle (TT). A expressão gênica de proteínas reguladoras do metabolismo lipídico e do processo inflamatório (CPT I e II, L-FABP, PPAR-alfa, NFB, IB, RXR, COX-2, assim como o conteúdo protéico de NFB, PPAR<font face=\"Symbol\">&#945; e CPT II e a atividade máxima do complexo CPT foram medidos. Ainda, avaliou-se a concentração de IL-6, TNF-<font face=\"Symbol\">&#945; e IL-10 a concentração de PGE2. Os resultados obtidos apontam restabelecimento da capacidade de oxidar e secretar lipídios pelo fígado, bem como o efeito anti-inflamatório deste. Em conclusão, sugere-se uma associação entre a redução na concentração de PGE2 ao aumento na expressão gênica e protéica do PPAR<font face=\"Symbol\">&#945; pelo treinamento no controle da inflamação, contudo mais estudos são necessários. / Cancer Cachexia is a paraneoplastic syndrome characterised by marked disruption of lipid metabolism. The liver suffers marked physiological alterations during cancer cachexia including hepatic steatosis, triggered by impaired lipid secretion, augmented uptake and decrease oxidation. Regular exercise training is well known to induce improvement of metabolic capacity in the liver. We adressed the effects of training upon liver of Walker 256 tumor-bearing rats. Male Wistar rats were randomly assigned to the following groups: sedentary control (SC), sedentary tumour-bearing (ST), trained control (TC) and trained tumour-bearing rats (TT). Gene expression of CPT I and II, L-FABP, PPAR-alpha, NFB, IB, RXR, COX-2, as well as NFB, PPAR-alpha and CPT II protein content and the maximal activity of CPT I and II were assessed. The IL-6, TNF-<font face=\"Symbol\">&#945; and IL-10 content in the liver and the role of exercise training upon PGE2 content was also evaluated. The results indicate the reestablishment of lipid oxidation and secretion capacity by the liver beyond of the anti-inflammatory exercise training. In conclusion, the present results suggest an association between a lower PGE2 levels in contrast to a higher PPAR<font face=\"Symbol\">&#945; gene and protein expression through exercise training upon inflammation and lipid metabolism modulation. However, more data are necessary to elucidate the exact mechanisms.

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