Thesis (MSc. (Human Physiology, Faculty of Health Sciences))--University of Pretoria, 2008. / Summary in English. Includes bibliographical references.

Thesis (doctoral)--Nijmegen, 1982.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-25T12:21:12Z No. of bitstreams: 2 Dissertação - Cíntia do Carmo e Silva - 2016.pdf: 1705558 bytes, checksum: f3f7616f0bd9d70c3439ec18c38eef3f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-25T12:21:31Z (GMT) No. of bitstreams: 2 Dissertação - Cíntia do Carmo e Silva - 2016.pdf: 1705558 bytes, checksum: f3f7616f0bd9d70c3439ec18c38eef3f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-25T12:21:31Z (GMT). No. of bitstreams: 2 Dissertação - Cíntia do Carmo e Silva - 2016.pdf: 1705558 bytes, checksum: f3f7616f0bd9d70c3439ec18c38eef3f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-21 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Previous studies have demonstrated a protective effect of the Ang-(1-7)/Mas receptor axis on pathological cardiac hypertrophy. Also, the involvement of Mas receptor in the exercise-induced cardiac hypertrophy has been suggested. However, the role of the Ang-(1-7)/Mas receptor on pregnancy-induced cardiac remodeling remains unknown. Thus, the aim of this study was to evaluate the participation of the Mas receptor in the development of pregnancy and hypertrophy, fibrosis and cardiac function during pregnancy. Female Wistar rats were randomly shared in 3 groups: control (W-NP), pregnant (W-P), and pregnant treated with A-779 (W-P + A-779). Wild type and Masknockout mice were distributed in non-pregnant (WT and KO) and pregnant (WT-P and KO-P) groups. Gestational parameters such as, maternal weight, placental weight, fetus weight, fetus/placenta ratio, fertility, Loss pre embryonic, Loss pos embryonic were evaluated. Systolic blood pressure (SBP) was measured by tail-cuff plethysmography. The medial part of the left ventricle (LV) was collected for cardiomyocytes morphometry analysis and extracellular matrix proteins deposition. Echocardiographic analysis was used to evaluate the cardiac function. Mas receptor blockade or genetic deletion of Mas did not alter the fertility or embryonic and fetal development. However, the Mas receptor antagonist decreased placental weight and increased fetus placenta ratio in rats. The pregnant KO mice presented a decreased maternal and fetal weight and increased fetus/placenta ratio. SBP was not changed by pregnancy or A-779 treatment in the Wistar rats. Pharmacological blockade or genetic deletion of Mas receptor attenuates the pregnancy-induced myocyte hypertrophy. The A-779 treatment or genetic deletion of the Mas receptor increased the collagen III deposition in LV from pregnant animals. KO mice presented a lower ejection fraction, fraction shortening, stroke volume and higher end systolic volume compared to WT. Interestingly, the pregnancy restored these parameters. In conclusion, these data show that Mas receptor can alter gestational and maternal parameters, and this is involved in the cardiomyocyte hypertrophy and in the control of the collagen III deposition in pregnancy condition. These alterations are associated with improvement of the cardiac function through Mas-independent mechanism. / Estudos anteriores mostraram que o eixo Ang- (1-7) / receptor Mas possue efeito protetor na hipertrofia cardíaca patológica. Além disso, o envolvimento de receptor Mas na hipertrofia cardíaca induzida por exercício tem sido sugerida. No entanto, o papel da Ang- (1-7) / receptor Mas no remodelamento cardíaco induzido pela gestação permanece desconhecido. Diante disto, o objetivo desse estudo foi avaliar a participação do receptor Mas no desenvolvimento da gestação e na hipertrofia, fibrose e função cardíaca durante a gestação. Ratas Wistar foram randomizadas aleatoriamente em 3 grupos: controle (W-NP), gestante (W-P) e gestante tratada com A-779 (W-P + A-779). Camundongas Wild type e Knockout para o receptor Mas foram randominazadas em grupos não-grávidas (WT e KO) e grávidas (WT-P e KO-P). Parâmetros gestacionais como peso materno, peso placentário, peso fetal, razão feto/placenta, fertilidade, perda pré-embrionária e perda pós-embrionária foram avaliados. A pressão arterial sistólica (PAS) foi medida por pletismografia de cauda. A parte medial do ventrículo esquerdo (VE) foi coletado para análise morfométrica do cardiomiócito e deposição de proteínas na matriz extracelular. Análise por ecocardiografia foi utilizada para avaliar a função cardíaca. O bloqueio ou a deleção genética do Mas não altera a fertilidade, o desenvolvimento embrionário ou fetal. No entanto, o bloqueio do Mas reduziu o peso placentário e aumentou a relação feto/placenta nas ratas. Já nos animais KO gestantes foi observado menor ganho de peso materno e fetal, o que acarretou em aumento da razão feto/placenta. A PAS não foi alterada pela gestação ou tratamento com A-779 nas ratas Wistar. O bloqueio farmacológico ou deleção genética de receptor Mas atenuou a hipertrofia dos miócitos induzida pela gravidez. O tratamento A-779 ou deleção genética do receptor Mas aumentou a deposição de colágeno III do VE das gestantes. KO apresentaram uma menor fração de ejeção, fração de encurtamento, volume sistólico e aumento do volume sistólico final em comparação com WT. Curiosamente, a gravidez restaurou esses parâmetros. Em conclusão, estes dados demonstraram que o receptor Mas pode alterar parâmetros maternos e gestacionais, bem como está envolvido na hipertrofia dos cardiomiócitos e no controle da deposição de colágeno III na gestação. Essas alterações estão associadas com a melhora da função cardíaca por meio de mecanismos independente do Mas

Phenylethanolamine-N-methyltransferase (Pnmt) catalyzes the conversion of noradrenaline to adrenaline and is the last enzyme in the catecholamine biosynthetic pathway. Pnmt serves as a marker for adrenergic cells, and lineage-tracing experiments have identified the embryonic heart and hindbrain region as the first sites of Pnmt expression in the mouse. Pnmt expression in the heart occurs before the adrenal glands have formed and prior to sympathetic innervation, suggesting that the heart is the first site of catecholamine production in the mouse. The function of these Pnmt+ cells in heart development remains unclear. In the present study, we test the hypothesis that (i) a genetic ablation technique utilizing a suicide reporter gene selectively destroys Pnmt cells in the mouse, and (ii) Pnmt cells are required for normal cardiovascular and neurological function. To genetically ablate adrenergic cells, we mated Pnmt-Cre mice, in which Cre-recombinase is under the transcriptional regulation of the Pnmt promoter, and a Cre -activated diphtheria toxin A (DTA) mouse strain (ROSA26-eGFP-DTA), thereby causing activation of the toxic allele (DTA) in Pnmt-expressing (adrenergic) cells resulting in selective "suicide" of these cells in approximately half of the offspring. The other half serve as controls because they do not have the ROSA26-eGFP-DTA construct. In the Pnmt+/Cre; R26+/DTA offspring, we achieve a dramatic reduction in Pnmt transcript and Pnmt immunoreactive area in the adrenal glands. Furthermore, we show that loss of Pnmt cells results in severe left ventricular dysfunction that progressively worsens with age. These mice exhibit severely reduced cardiac output and ejection fraction due to decreased LV contractility and bradycardia at rest. Surprisingly, these mice appear to have a normal stress response, as heart rate and ejection fraction increased to a similar extent compared to controls. In addition to baseline cardiac dysfunction, these mice fail to gain body weight in a normal manner and display gross neurological dysfunction, including muscular weakness, abnormal gaiting, and altered tail suspension reflex, an indicator of neurological function. This work demonstrates that selective Pnmt cell destruction leads to severe left ventricular dysfunction, lack of weight gain, and neurological dysfunction. This novel mouse is expected to shed insight into the role of Pnmt cells in the heart, and suggests a role for Pnmt cells in neurological regulation of feeding behavior, metabolism, and motor control.

PhD / The overall objective of this thesis is to provide additional data to assist clinicians and experimental neurologists alike in the quest for better understanding, more accurately diagnosing and more successfully treating patients suffering from Parkinson’s disease (PD). The general theme of the thesis is the interaction between certain environmental stimuli, including the exposure to adverse events during early central nervous system (CNS) development and the manifestation of elements of neurodegeneration, whether by means of neurochemical changes or expressed as a dysfunctional voluntary motor system. The first chapter provides a general introduction to the research theme of the thesis. This includes, in particular, a discussion on current understanding concerning the etiology and clinical profile of PD, the relative contribution made by genetic factors compared to environmental ones, and current treatment strategies for treating the disease. Mention is also made of the failure of these therapeutic applications for reversing or protecting against the disease, due to the side-effects associated with them. The material covered in chapter 1 provides the basis for the more complete discussion concerning these various aspects, contained in the chapters to follow. The overall aim was also to characterise the effects of commonly used toxin-induced animal models of PD, and the extent of vulnerability that the CNS displays towards them. The destruction of dopaminergic neurons following the administration of 6-OHDA at targeted points along the nigrostriatal tract is used extensively to model PD pathology in rats and is an established animal model of the disease. However, mature or even aged animals are mainly used in these studies, while the effects that the toxin might have on the developing CNS remain unclear. The study reported in chapter 4 aimed to elucidate some of 6-OHDA’s actions on the young adolescent (35 days-old) CNS by comparing the motor and biochemical effects of a unilateral infusion of the toxin into two anatomically distinct basal ganglia loci: The medial forebrain bundle (MFB) and the striatum. Animals were randomly assigned to receive either a direct delivery of 6-OHDA (12μg/4μl) into the MFB or an indirect injection, into the striatum. Although both lesion types were used, the MFB model is considered a more accurate portrayal of end-stage PD, while the striatum-model better reflects the long-term progressive pathology of the disease. The different lesions’ effects on motor function were determined by observing animal’s asymmetrical forelimb use to correct for weigh shifting during the vertical exploration of a cylindrical enclosure. Following the final behavioral assessment, the concentration of dopamine (DA) and DA metabolites remaining in the post-mortem brains were determined using 4 HPLC electrochemistry (HPLC-EC) and the levels compared between the two groups. The HPLC-EC results revealed a compensatory effect for DA production and DA turnover on the lesioned hemisphere side of the toxin-infused animal group. Thus, following 6-OHDA treatment, there appears to be extensive adaptive mechanisms in place within the remaining dopaminergic terminals that may be sufficient for maintaining relatively high extracellular and synaptic concentrations of DA. However, since substantial changes in motor-function were observed, it is suggested that the capacity of the remaining dopaminergic neurons to respond to increased functional demands may be limited. In addition, the behavioral results indicate that the distinct indices relating to different functional deficits depend on the lesioning of anatomically distinct structures along the nigrostrial tract. It has long been known that far fewer women are diagnosed with PD than men are. This seeming protection offered to females against degenerative disease of the CNS may relate to estrogen, although the hormone’s mechanism of action on the dopaminergic system is poorly defined. With an estimated 10-15 million women using oral contraceptives (OCs) in the United States alone, the aim of chapter 2 was to examine the evidence for a possible relationship between PD and the female reproductive hormone estrogen. A review of the current literature available on the topic was performed by consulting Medline, and by performing a search of the case-reports contained within the World Health Organization’s (WHO) International Drug Monitoring database, for possible PD-related symptoms that may arise from estrogen replacement therapy (ERT). The results, whilst conflicting, seem to suggest that estrogen protects women from obtaining the disease, or at least some features of it. Intensive research efforts are called for, with sufficient power to establish the relationship between ERT and the onset and development of parkinsonism. Chapter 3 reports on the results obtained from an experiment that subjected young Sprague-Dawley rats, 35 days of age, to a lower and a higher dose of 6-OHDA delivered to the MFB. Control rats received equivalent saline infusions. At 14 days post-surgery, the rats were evaluated for forelimb akinesia. For the higher dose of 6- OHDA the female rats were less impaired than males in making adjustment steps in response to a weight shift and in the vibrissae-evoked forelimb placing test. In addition, Tyrosine hydroxylase (TH) immunoreactivity was significantly higher for the female rats. Early gender differences in cell survival factors and/or other promoters of neuroplasticity may have contributed to the beneficial outcome seen in the females. For example, nerve growth factor (NGF) was found to be higher in the female rats following administration of the DA neurotoxin. It is unclear whether gonadal steroids are involved, and, if so, whether female hormones are protective or whether male hormones are prodegenerative. Determining the mechanisms for the improved outcome seen in the young female rats may lead to potential treatment strategies against PD. 5 Many studies have shown that early life stress may lead to impaired brain development, and may be a risk factor for developing psychiatric diseases, including clinical depression. However, few studies have investigated the impact that early stress may have on the onset and development of neurodegenerative disorders such as PD. The study reported on in chapter 5 conjointly subjected rat pups to a maternal separation (MS) paradigm that is a well characterised model of adverse early life events, and a unilateral, intrastriatal injection of 6- OHDA. The combined effects of these models on motor deficits and brain protein levels were investigated. Specifically, the animals were assessed for behavioral changes at 28 days postlesion with a battery of tests that are sensitive to the degree of DA loss sustained. The results show that animals that had been subjected to MS display poorer performance in the vibrissae and single-limb akinesia test compared to non-MS control animals (that had also been subjected to the toxin exposure). In addition, there was a significant increase in the loss of TH staining in MS rats compared to non-MS ones. The results from this study therefore suggest that exposure to adverse experiences during the early stages of life may contribute towards making dopaminergic neurons more susceptible to subsequent insults to the CNS occurring during mature stages of life. Therefore, taken together, early exposure to stress may predispose an individual towards the onset and development of neurodegenerative disease, which especially becomes a threat during the later stages of adult life. Moreover, within the framework of these characteristics, the capacity of a widely-used pharmacological agent (statins) was tested for possible future therapeutic application in PD (chapter 7). Although the precise cause of sporadic PD remains an enigma, evidence suggests that it may associate with defective activity of complex I of the mitochondrial electron transport chain. Mitochondrial DNA transmit and express this defect in host cells, resulting in increased oxygen free radical production, depressed antioxidant enzyme activities, and greater susceptibility to apoptotic cell death. Simvastatin is a member of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) group of drugs that are widely used for lowering cholesterol levels in patients who display elevated concentrations of low-density lipoprotein cholesterol. The study aimed to investigate the effects that statin-treatment have on motor-function and at the mitochondrial-protein level, using rotenone, a mitochondrial complex I inhibitor, as a rat-model of PD. Adult male Sprague-Dawley rats were treated either with simvastatin (6mg/day for 14 days) or with a placebo. Two different tests to assess motor function were used: The apomorphine-rotation test, and the vibrissae-elicited forelimb placement test. Following the drug administration protocol, the nigrostriatal tract was unilaterally lesioned with either rotenone (3 μg/4 μl) or, for the controls, were sham-operated by infusing the vehicle (DMSO:PEG) only. Five days later the rats were killed and a highly purified concentration of isolated mitochondria was prepared from the substantia nigra (SN) sections. 2- 6 Dimensional electrophoresis (2-DE) with subsequent identification of the spots using electronspray ionization quadruple time-of-flight mass spectrometrical (ESI-Q-TOF MS) was performed and the results BLAST-searched using bio-informatics tools for naming the identified peptides. The motor test results indicate that while unilateral rotenone causes behavioral asymmetries, treatment with simvastatin improved motor function relative to the rotenoneinduced ones. Mass Spectroscopy identified 23 mitochondrial proteins that differ significantly in protein expression (p < 0.05) following simvastatin treatment. The altered proteins were broadly classified according to their cellular function into 6 categories, with the majority involved in energy metabolism. This study effectively illustrated how neuroproteomics, with its sophisticated techniques and non-biased ability to quantify proteins, provides a methodology with which to study the changes in neurons associated with neurodegeneration. As an emerging tool for establishing disease-associated protein profiles, it also generates a greater understanding as to how these proteins interact and undergo post-translational modifications. Furthermore, due to the advances made in bioInformatics, insight is created concerning their functional characteristics. Chapter 4 summarises the most prominent proteomics techniques and discuss major advances made in the fast-growing field of neuroproteomics in PD. Ultimately, it is hoped that the application of this technology will lead towards a presymptomatic diagnosis of PD, and the identification of risk factors and new therapeutic targets at which pharmacological intervention can be aimed. The final chapter (chapter 8) provides a retrospective look at the academic work that had been performed for the purpose of this thesis, recaps on the main findings, and also highlights certain aspects of the project and provides relevant suggestions for future research. Lastly, the appendix provides a detailed overview of the methods followed for the experiments described in this thesis. It provides not only a comprehensive description of the techniques that had been followed, but provides information concerning the care taken with the animals (i.e. post-surgery) in order to control for the potential influence of experimental variables on the results.

INTRODUÇÃO: A sobrecarga hemodinâmica pulmonar (SHP) está associada a entidades clínicas de elevada morbimortalidade como: o edema pulmonar pós-pneumonectomia, o tromboembolismo pulmonar, o transplante pulmonar e a situações fisiológicas como o exercício físico. Vários pontos da sua fisiopatologia não estão elucidados. OBJETIVOS: Estudar as alterações fisiopatológicas pulmonares e cardíacas induzidas pela SHP. MÉTODOS: Vinte porcos Large White foram anestesiados, intubados e submetidos à ventilação mecânica a volume seguida por toracotomia bilateral trans-esternal. Os elementos dos lobos pulmonares foram isolados através de dissecção cirúrgica, com reparo das artérias pulmonares do lobo inferior direito, lobo mediastinal e pulmão esquerdo. Os animais foram randômicamente alocados em 4 grupos de estudo (n=5), sendo um controle (C) e três de SHP (LI, LII e LIII) induzida através da oclusão das artérias pulmonares específicas. No grupo C (controle), todos os lobos tiveram sua perfusão mantida. No grupo LI, somente o pulmão direito foi perfundido. No grupo LII, o pulmão direito menos o lobo inferior e no grupo LIII, o pulmão direito menos os lobos mediastinal e inferior, obstruindo a vasculatura pulmonar em 42, 76 e 82% respectivamente. Variáveis de hemodinâmica e de trocas gasosas foram monitoradas durante 60 minutos de SHP. Ao final do regime de SHP o lobo médio foi ressecado para análise de variáveis estruturais: morfometria (alveolar e vascular) e cálculo da relação peso úmido / peso seco. Na análise estatística foram utilizados ajustes de modelos lineares mistos com estrutura de variâncias e covariâncias, ANOVA a um fator, regressão linear simples e regressão linear de efeitos mistos com intercepto e tendência aleatório. RESULTADOS: Nas comparações intergrupos houve diferenças significativas ao longo dos 60 minutos de SHP nas variáveis hemodinâmicas: Frequencia cardíaca (p=0,004), Pressão arterial média (p=0,01), Índice sistólico (p=0,002), Pressão arterial pulmonar (p=0,001) e Pressão capilar pulmonar (p<0,0001). Trocas gasosas: Relação PaO2/FiO2 (p=0,002), PaCO2 (p<0,0001), pH (p<0,0001), Índice de consumo tecidual de O2 (p=0,02), Fração de shunt (p=0,03). Estruturais: Edemas alveolar e perivascular (p<0,0001) em ambos e Relação peso úmido / peso seco (p=0, 005). Nas comparações intergrupos, não houve diferenças significativas das variáveis: Índice cardíaco (p=0,94), HCO3 (p=0,63), Índice de oferta tecidual de O2 (p=0,89) e Taxa de extração tecidual de O2 (p=0,08). CONCLUSÕES: A SHP promoveu disfunção pulmonar significativa em pulmões previamente hígidos com alterações estruturais (edema alveolar e perivascular) e elevação das pressões arterial e capilar pulmonar. A função cardíaca foi preservada apesar de grande redução no leito vascular pulmonar (82% no grupo LIII). No grupo LII houve melhora da disfunção pulmonar ao longo do tempo de SHP / INTRODUCTION: The pulmonary hemodynamic overload (PHO) is associates to high mortality and morbidity clinical entities as: postpneumonectomy pulmonary edema, pulmonary thromboembolism, lung transplantation and physiological situations as physical exercise. Some pathophysiological aspects related to PHO are not elucidated. OBJECTIVES: To study pulmonary and cardiac pathopysiological alterations induced by PHO. METHODS: Twenty Large White pigs were anesthetized, intubated and subjected to volume controlled mechanical ventilation followed to median sternotomy. Pulmonary lobes structures were isolated by surgical dissection and pulmonary arteries of left lung, right lower lobe and mediastinal lobe were completely isolated. The animals were randomized into 4 groups (n=5 each) with one control (C) and three of PHO (LI, LII and LIII) induced by pulmonary arterial occlusions specifics for each group. In the control group (C), all lobes were perfused, ie none of arteries were occluded. In the LI group, only the right lung was perfused; in the LII group, the right lung but the lower lobe; in LIII group, the right lung but the lower and mediastinal lobes, obstructing the pulmonary vasculature in 42, 76 and 82% respectively. Hemodynamics and gas exchange variables were monitored during 60 minutes of PHO. At the end of the study, the middle lobe was resected for analysis of structural variables: morphometry (alveolar and vascular) and calculation of the wet weight / dry weight ratio. Statistical analysis settings were used with mixed linear models of variance and covariance structure, a one-way ANOVA, simple linear regression and mixed effects linear regression with random intercept and trend. RESULTS: In intergroup comparisons there were significant differences during the 60 minutes of PHO in hemodynamic variables: Heart rate (p=0, 004), Systemic arterial pressure (p=0,01), Systolic index (p=0,002), Pulmonary arterial pressure (p=0,001) and Pulmonary capillary pressure (p <0,0001). Gas exchange: for PaO2/FiO2 ratio (p=0,002), PaCO2 (p<0,0001), arterial pH (p<0,0001), O2 consumption index (p=0,02), Shunt (p=0,03). Structural: perivascular and alveolar edema (p<0,0001) in both and the wet weight / dry weight ratio (p=0,005). There were no significant differences in intergroup comparisons of variables: Cardiac index (p=0,94), arterial HCO3 (p=0,63), O2 offer index (p=0,89) and O2 extraction (p=0,08). CONCLUSIONS: The PHO promoted significant pulmonary dysfunction in previously healthy lungs with structural changes (alveolar and perivascular edema) and increased arterial and pulmonary capillary pressures. Cardiac function was preserved despite the large reduction in pulmonary vascular bed (82% in group LIII). In LII group occurred reverse of pulmonary dysfunction with past of PHO time

OBJETIVOS: Comparar as respostas do Teste de Esforço Cardiopulmonar (TECP) em imersão, numa esteira subaquáticas, com as de solo; investigar e entender o desempenho cardiorrespiratório de coronariopatas (DAC) durante esforço em imersão comparando-os aos do grupo de indivíduos saudáveis. Entender os procedimentos, materiais e equipamentos necessários na realização do teste em imersão e na coleta de dados reprodutíveis e confiáveis. MÉTODOS: O estudo contou com 40 indivíduos, sendo: 20 pacientes com diagnóstico médico de DAC, 63,7 ± 8,89 anos de idade e classificação I e II segundo New York Heart Association (NYHA) e 20 sujeitos saudáveis, 64,7 ± 7,09 anos; realizaram dois testes ergoespirométricos em uma instalação equipada com esteira no solo, piscina aquecida, esteira subaquática, analisador de gases e Eletrocardiograma (ECG). Foi calculado o Poder Estatístico do teste para ANOVA com erro beta de 0.861. Por ser um exame normatizado tecnicamente e reconhecidamente seguro, o primeiro teste foi realizado em esteira no solo de 3 a 7 dias deste, o segundo teste foi realizado em esteira subaquática com imersão ao nível do manúbrio, em uma piscina com temperatura controlada entre 33 e 34°C. Os dados foram coletados em 5 momentos expressivos: 1- Repouso; 2- Limiar Anaeróbio; 3- Ponto de Compensação Respiratória; 4- Esforço Máximo e 5- Recuperação. RESULTADOS: A análise de variância deste estudo revelou haver efeito principal para DAC nas variáveis: FC, VO2 e VCO2; (p > 0.01) em relação ao ambiente. O teste em imersão apresentou significância nas variáveis FC, VO2, VCO2 e VO2/FC (p > 0.01). As interações com estágio caracterizam o comportamento dos sujeitos ao longo do experimento e neste contexto, as variáveis PEB, FC, VO2, VCO2 e VO2/FC (p > 0.01) mostraram interações significantes entre estágio e ambiente. Em adição, há interação significante entre etiologia e estágio para as variáveis FC, VO2 e VCO2 (p > 0.01). DAC e saudáveis possuem comportamentos diferentes no decorrer dos estágios do experimento em relação a estas variáveis. Alterações eletrocardiográficas compatíveis com isquemia miocárdica ou arritmia não foram observadas e a Pressão Arterial Sistólica e Diastólica (PAS/D) não se alterou significativamente. Os indivíduos deste estudo tiveram percepção de esforço na Escala de Borg menor na água em todos os estágios do que em terra (p > 0.01). CONCLUSÃO: Os achados deste estudo mostram que os procedimentos operacionais, materiais e equipamentos utilizados no TECP em piscina produziram dados reprodutíveis, confiáveis e que atenderam as determinações estabelecidas no \"Clinician´s Guide to Cardioplulmonary Exercice Testing in Adults\". O esforço foi bem tolerado por todos os participantes, sem ocorrência de evento adverso. As diferenças estatísticas observadas nos testes na água contra os de solo nos levam a entender que o exercício em imersão pode ser realizado por pacientes com DAC e que os efeitos fisiológicos da imersão não causam qualquer risco para este grupo. Conclui-se também que por ser reprodutível e confiável, o teste em imersão pode ser adotado para prognosticar capacidades individuais de pacientes coronariopatas ao exercício dinâmico em piscina / OBJECTIVES: To compare responses to a Cardiopulmonary Exercise Test (CPX) conducted in water, (on a underwater treadmill), with the responses to the same tests conducted on land, (on a land treadmill); to investigate and assess the cardiorespiratory performance of coronary artery disease (CAD) patients while immersed in warm water when compared to the performance of healthy individuals; to assess the procedures, feasibility, resources and equipment required for conducting a CPX in individuals in water so as to collect reliable and replicable data. METHODS: The sample was comprised by 40 subjects, 20 of whom diagnosed with coronary artery disease (CAD) and aged 63.7 ± 8.89, functional class I and II (in compliance with the New York Heart Association [NYHA]), and 20 healthy subjects aged 64.7 ± 7.09. Two CPX tests were conducted in a facility equipped with a land treadmill, a warm pool, an underwater treadmill, a gas analyzer and an electrocardiogram (ECG) device. The statistical significances were calculated through a ANOVA test with (1 - beta) power of 0.861. As CPX is technically regulated and acknowledged as safe the first test was conducted on a land treadmill and the second test was conducted 3-7 days later on an underwater treadmill. Subjects were submerged in a temperature-controlled pool (33-34oC) with water at manubrium level. Data were collected at 5 relevant test stages or cardiorespiratory levels: 1- Rest; 2- Anaerobic Threshold (AT); 3- Respiratory Compensation Point (RCP); 4- Maximum Effort (ME); and 5- Recovery (R). FINDINGS: ANOVA analysis showed a major significance for CAD subjects regarding variables HB, VO2 and VCO2 (p < 0.01) in relation to the environment. The test performed with submerged patients showed some significance for variables HB, VO2, VCO2 and VO2/HB (p < 0.01). The stages for data collected featured the subjects performance throughout this experiment, and within the given context, variables RPE, HB, VO2, VCO2 and VO2/HB (p < 0.01) showed significant interactions between test stage and environment. Additionally, there was a significant interaction between the etiology and the test stage for variables HB, VO2 and VCO2 (p < 0.01). CAD patients and healthy subjects showed different performances throughout the test stages in relation to the referred variables. Electrocardiographic (ECG) changes that are compatible with myocardial ischemia or arrhythmia were not observed. Systolic and diastolic blood pressure (SDBP) did not show significant changes. The subjects of this study showed lower rates of Borg\'s perceived exertion scale in the water than at every one of the test stages on land (p < 0.01). CONCLUSION: This study show that the procedures, resources and equipment used during CPX conducted in a warm pool demonstrated to be feasible and yielded replicable and reliable data, which complied with the provisions of the \"Clinician´s Guide to Cardiopulmonary Exercise Testing in Adults\". The effort exerted was well tolerated by all the participants without any adverse events. Statistical differences observed in water versus on land allow us to conclude that patients with CAD are able to carry out physical activities in water and that the physiological effects of immersion do not present any risk for such patients. We may also conclude that given its replicability and reliability, CPX conducted in water may be used to diagnose and to estimate the exertion capability of CAD patients to perform dynamic exercise in a warm pool

OBJETIVOS: Comparar as respostas do Teste de Esforço Cardiopulmonar (TECP) em imersão, numa esteira subaquáticas, com as de solo; investigar e entender o desempenho cardiorrespiratório de coronariopatas (DAC) durante esforço em imersão comparando-os aos do grupo de indivíduos saudáveis. Entender os procedimentos, materiais e equipamentos necessários na realização do teste em imersão e na coleta de dados reprodutíveis e confiáveis. MÉTODOS: O estudo contou com 40 indivíduos, sendo: 20 pacientes com diagnóstico médico de DAC, 63,7 ± 8,89 anos de idade e classificação I e II segundo New York Heart Association (NYHA) e 20 sujeitos saudáveis, 64,7 ± 7,09 anos; realizaram dois testes ergoespirométricos em uma instalação equipada com esteira no solo, piscina aquecida, esteira subaquática, analisador de gases e Eletrocardiograma (ECG). Foi calculado o Poder Estatístico do teste para ANOVA com erro beta de 0.861. Por ser um exame normatizado tecnicamente e reconhecidamente seguro, o primeiro teste foi realizado em esteira no solo de 3 a 7 dias deste, o segundo teste foi realizado em esteira subaquática com imersão ao nível do manúbrio, em uma piscina com temperatura controlada entre 33 e 34°C. Os dados foram coletados em 5 momentos expressivos: 1- Repouso; 2- Limiar Anaeróbio; 3- Ponto de Compensação Respiratória; 4- Esforço Máximo e 5- Recuperação. RESULTADOS: A análise de variância deste estudo revelou haver efeito principal para DAC nas variáveis: FC, VO2 e VCO2; (p > 0.01) em relação ao ambiente. O teste em imersão apresentou significância nas variáveis FC, VO2, VCO2 e VO2/FC (p > 0.01). As interações com estágio caracterizam o comportamento dos sujeitos ao longo do experimento e neste contexto, as variáveis PEB, FC, VO2, VCO2 e VO2/FC (p > 0.01) mostraram interações significantes entre estágio e ambiente. Em adição, há interação significante entre etiologia e estágio para as variáveis FC, VO2 e VCO2 (p > 0.01). DAC e saudáveis possuem comportamentos diferentes no decorrer dos estágios do experimento em relação a estas variáveis. Alterações eletrocardiográficas compatíveis com isquemia miocárdica ou arritmia não foram observadas e a Pressão Arterial Sistólica e Diastólica (PAS/D) não se alterou significativamente. Os indivíduos deste estudo tiveram percepção de esforço na Escala de Borg menor na água em todos os estágios do que em terra (p > 0.01). CONCLUSÃO: Os achados deste estudo mostram que os procedimentos operacionais, materiais e equipamentos utilizados no TECP em piscina produziram dados reprodutíveis, confiáveis e que atenderam as determinações estabelecidas no \"Clinician´s Guide to Cardioplulmonary Exercice Testing in Adults\". O esforço foi bem tolerado por todos os participantes, sem ocorrência de evento adverso. As diferenças estatísticas observadas nos testes na água contra os de solo nos levam a entender que o exercício em imersão pode ser realizado por pacientes com DAC e que os efeitos fisiológicos da imersão não causam qualquer risco para este grupo. Conclui-se também que por ser reprodutível e confiável, o teste em imersão pode ser adotado para prognosticar capacidades individuais de pacientes coronariopatas ao exercício dinâmico em piscina / OBJECTIVES: To compare responses to a Cardiopulmonary Exercise Test (CPX) conducted in water, (on a underwater treadmill), with the responses to the same tests conducted on land, (on a land treadmill); to investigate and assess the cardiorespiratory performance of coronary artery disease (CAD) patients while immersed in warm water when compared to the performance of healthy individuals; to assess the procedures, feasibility, resources and equipment required for conducting a CPX in individuals in water so as to collect reliable and replicable data. METHODS: The sample was comprised by 40 subjects, 20 of whom diagnosed with coronary artery disease (CAD) and aged 63.7 ± 8.89, functional class I and II (in compliance with the New York Heart Association [NYHA]), and 20 healthy subjects aged 64.7 ± 7.09. Two CPX tests were conducted in a facility equipped with a land treadmill, a warm pool, an underwater treadmill, a gas analyzer and an electrocardiogram (ECG) device. The statistical significances were calculated through a ANOVA test with (1 - beta) power of 0.861. As CPX is technically regulated and acknowledged as safe the first test was conducted on a land treadmill and the second test was conducted 3-7 days later on an underwater treadmill. Subjects were submerged in a temperature-controlled pool (33-34oC) with water at manubrium level. Data were collected at 5 relevant test stages or cardiorespiratory levels: 1- Rest; 2- Anaerobic Threshold (AT); 3- Respiratory Compensation Point (RCP); 4- Maximum Effort (ME); and 5- Recovery (R). FINDINGS: ANOVA analysis showed a major significance for CAD subjects regarding variables HB, VO2 and VCO2 (p < 0.01) in relation to the environment. The test performed with submerged patients showed some significance for variables HB, VO2, VCO2 and VO2/HB (p < 0.01). The stages for data collected featured the subjects performance throughout this experiment, and within the given context, variables RPE, HB, VO2, VCO2 and VO2/HB (p < 0.01) showed significant interactions between test stage and environment. Additionally, there was a significant interaction between the etiology and the test stage for variables HB, VO2 and VCO2 (p < 0.01). CAD patients and healthy subjects showed different performances throughout the test stages in relation to the referred variables. Electrocardiographic (ECG) changes that are compatible with myocardial ischemia or arrhythmia were not observed. Systolic and diastolic blood pressure (SDBP) did not show significant changes. The subjects of this study showed lower rates of Borg\'s perceived exertion scale in the water than at every one of the test stages on land (p < 0.01). CONCLUSION: This study show that the procedures, resources and equipment used during CPX conducted in a warm pool demonstrated to be feasible and yielded replicable and reliable data, which complied with the provisions of the \"Clinician´s Guide to Cardiopulmonary Exercise Testing in Adults\". The effort exerted was well tolerated by all the participants without any adverse events. Statistical differences observed in water versus on land allow us to conclude that patients with CAD are able to carry out physical activities in water and that the physiological effects of immersion do not present any risk for such patients. We may also conclude that given its replicability and reliability, CPX conducted in water may be used to diagnose and to estimate the exertion capability of CAD patients to perform dynamic exercise in a warm pool

INTRODUÇÃO: A sobrecarga hemodinâmica pulmonar (SHP) está associada a entidades clínicas de elevada morbimortalidade como: o edema pulmonar pós-pneumonectomia, o tromboembolismo pulmonar, o transplante pulmonar e a situações fisiológicas como o exercício físico. Vários pontos da sua fisiopatologia não estão elucidados. OBJETIVOS: Estudar as alterações fisiopatológicas pulmonares e cardíacas induzidas pela SHP. MÉTODOS: Vinte porcos Large White foram anestesiados, intubados e submetidos à ventilação mecânica a volume seguida por toracotomia bilateral trans-esternal. Os elementos dos lobos pulmonares foram isolados através de dissecção cirúrgica, com reparo das artérias pulmonares do lobo inferior direito, lobo mediastinal e pulmão esquerdo. Os animais foram randômicamente alocados em 4 grupos de estudo (n=5), sendo um controle (C) e três de SHP (LI, LII e LIII) induzida através da oclusão das artérias pulmonares específicas. No grupo C (controle), todos os lobos tiveram sua perfusão mantida. No grupo LI, somente o pulmão direito foi perfundido. No grupo LII, o pulmão direito menos o lobo inferior e no grupo LIII, o pulmão direito menos os lobos mediastinal e inferior, obstruindo a vasculatura pulmonar em 42, 76 e 82% respectivamente. Variáveis de hemodinâmica e de trocas gasosas foram monitoradas durante 60 minutos de SHP. Ao final do regime de SHP o lobo médio foi ressecado para análise de variáveis estruturais: morfometria (alveolar e vascular) e cálculo da relação peso úmido / peso seco. Na análise estatística foram utilizados ajustes de modelos lineares mistos com estrutura de variâncias e covariâncias, ANOVA a um fator, regressão linear simples e regressão linear de efeitos mistos com intercepto e tendência aleatório. RESULTADOS: Nas comparações intergrupos houve diferenças significativas ao longo dos 60 minutos de SHP nas variáveis hemodinâmicas: Frequencia cardíaca (p=0,004), Pressão arterial média (p=0,01), Índice sistólico (p=0,002), Pressão arterial pulmonar (p=0,001) e Pressão capilar pulmonar (p<0,0001). Trocas gasosas: Relação PaO2/FiO2 (p=0,002), PaCO2 (p<0,0001), pH (p<0,0001), Índice de consumo tecidual de O2 (p=0,02), Fração de shunt (p=0,03). Estruturais: Edemas alveolar e perivascular (p<0,0001) em ambos e Relação peso úmido / peso seco (p=0, 005). Nas comparações intergrupos, não houve diferenças significativas das variáveis: Índice cardíaco (p=0,94), HCO3 (p=0,63), Índice de oferta tecidual de O2 (p=0,89) e Taxa de extração tecidual de O2 (p=0,08). CONCLUSÕES: A SHP promoveu disfunção pulmonar significativa em pulmões previamente hígidos com alterações estruturais (edema alveolar e perivascular) e elevação das pressões arterial e capilar pulmonar. A função cardíaca foi preservada apesar de grande redução no leito vascular pulmonar (82% no grupo LIII). No grupo LII houve melhora da disfunção pulmonar ao longo do tempo de SHP / INTRODUCTION: The pulmonary hemodynamic overload (PHO) is associates to high mortality and morbidity clinical entities as: postpneumonectomy pulmonary edema, pulmonary thromboembolism, lung transplantation and physiological situations as physical exercise. Some pathophysiological aspects related to PHO are not elucidated. OBJECTIVES: To study pulmonary and cardiac pathopysiological alterations induced by PHO. METHODS: Twenty Large White pigs were anesthetized, intubated and subjected to volume controlled mechanical ventilation followed to median sternotomy. Pulmonary lobes structures were isolated by surgical dissection and pulmonary arteries of left lung, right lower lobe and mediastinal lobe were completely isolated. The animals were randomized into 4 groups (n=5 each) with one control (C) and three of PHO (LI, LII and LIII) induced by pulmonary arterial occlusions specifics for each group. In the control group (C), all lobes were perfused, ie none of arteries were occluded. In the LI group, only the right lung was perfused; in the LII group, the right lung but the lower lobe; in LIII group, the right lung but the lower and mediastinal lobes, obstructing the pulmonary vasculature in 42, 76 and 82% respectively. Hemodynamics and gas exchange variables were monitored during 60 minutes of PHO. At the end of the study, the middle lobe was resected for analysis of structural variables: morphometry (alveolar and vascular) and calculation of the wet weight / dry weight ratio. Statistical analysis settings were used with mixed linear models of variance and covariance structure, a one-way ANOVA, simple linear regression and mixed effects linear regression with random intercept and trend. RESULTS: In intergroup comparisons there were significant differences during the 60 minutes of PHO in hemodynamic variables: Heart rate (p=0, 004), Systemic arterial pressure (p=0,01), Systolic index (p=0,002), Pulmonary arterial pressure (p=0,001) and Pulmonary capillary pressure (p <0,0001). Gas exchange: for PaO2/FiO2 ratio (p=0,002), PaCO2 (p<0,0001), arterial pH (p<0,0001), O2 consumption index (p=0,02), Shunt (p=0,03). Structural: perivascular and alveolar edema (p<0,0001) in both and the wet weight / dry weight ratio (p=0,005). There were no significant differences in intergroup comparisons of variables: Cardiac index (p=0,94), arterial HCO3 (p=0,63), O2 offer index (p=0,89) and O2 extraction (p=0,08). CONCLUSIONS: The PHO promoted significant pulmonary dysfunction in previously healthy lungs with structural changes (alveolar and perivascular edema) and increased arterial and pulmonary capillary pressures. Cardiac function was preserved despite the large reduction in pulmonary vascular bed (82% in group LIII). In LII group occurred reverse of pulmonary dysfunction with past of PHO time

Indiana University-Purdue University Indianapolis (IUPUI) / Recent advancements in the management of systemic glucose regulation in obesity/T2DM include drug therapies designed to utilize components of the incretin system specifically related to glucagon-like peptide 1 (GLP-1). More recently, GLP-1 has been investigated for potential cardioprotective effects. Several investigations have revealed that acute/sub-acute intravenous administration of GLP-1 significantly reduces myocardial infarct size following ischemia/reperfusion injury and improves cardiac contractile function in the settings of coronary artery disease, myocardial ischemia/reperfusion injury, and heart failure. Despite an abundance of data indicating that intravenous infusion of GLP-1 is cardioprotective, information has been lacking on the cardiac effects of iv GLP-1 in the MetS or T2DM population. Some important questions this study aimed to address are 1) what are the direct, dose-dependent cardiac effects of GLP-1 in-vivo 2) are the cardiac effects influenced by cardiac demand (MVO2) and/or ischemia, 3) does GLP-1 effect myocardial blood flow, glucose uptake or total oxidative metabolism in human subjects, and 4) are the cardiac effects of GLP-1 treatment impaired in the settings of obesity/MetS and T2DM. Initial studies conducted in canines demonstrated that GLP-1 had no direct effect on coronary blood flow in-vivo or vasomotor tone in-vitro, but preferentially increased myocardial glucose uptake in ischemic myocardium independent of effects on cardiac contractile function or coronary blood flow. Parallel translational studies conducted in the humans and Ossabaw swine demonstrate that iv GLP-1 significantly increases myocardial glucose uptake at rest and in response to increases in cardiac demand (MVO2) in lean subjects, but not in the settings of obesity/MetS and T2DM. Further investigation in isolated cardiac tissue from lean and obese/MetS swine indicate that this impairment in GLP-1 responsiveness is related to attenuated activation of p38-MAPK, independent of alterations in GLP-1 receptor expression or PKA-dependent signaling. Our results indicate that the affects of GLP-1 to reduce cardiac damage and increase left ventricular performance may be impaired by obesity/MetS and T2DM.