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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.
11

Beta 1 and Alpha 2C adrenergic receptor polymorphisms and response to beta blockers in heart failure patients /

Zolty, Ronald. January 2007 (has links)
Thesis (Ph.D. in Clinical Science) -- University of Colorado Denver, 2007. / Typescript. Includes bibliographical references (leaves 130-142). Free to UCD affiliates. Online version available via ProQuest Digital Dissertations;
12

Efeitos da infusão intravenosa de metaloproteinase-2 da matriz recombinante humana (rhMMP-2) em respostas ß-adrenérgicas = Effects of intravenous infusion of recombinant human matrix metalloproteinase-2 (rhMMP-2) in ß-adrenergic responses / Effects of intravenous infusion of recombinant human matrix metalloproteinase-2 (rhMMP-2) in ß-adrenergic responses

Ferraz, Karina Coutinho, 1986- 21 August 2018 (has links)
Orientador: José Eduardo Tanus dos Santos / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T15:51:02Z (GMT). No. of bitstreams: 1 Ferraz_KarinaCoutinho_D.pdf: 4092717 bytes, checksum: 304af959216055cd75432ac292abc300 (MD5) Previous issue date: 2012 / Resumo: Evidências clínicas e experimentais indicam o envolvimento de metaloproteinases da matriz extracelular (MMPs) na patogênese de diversas doenças, incluindo as doenças cardiovasculares. Particularmente, alterações na atividade da MMP-2 parecem desempenhar um importante papel na hipertensão, na insuficiência cardíaca e em outras alterações do sistema cardiovascular. Diversos estudos mostram vários alvos não relacionados à matriz extracelular para a MMP-2, incluindo proteínas intracelulares e mediadores vasoativos. Adicionalmente, diversos trabalhos indicam o envolvimento desta enzima na clivagem proteolítica de receptores ?1- e ?2-adrenérgicos. Embora alguns estudos tenham sugerido que a MMP-2 possa afetar o tônus vascular e prejudicar a função dos ?-adrenoreceptores, nenhum estudo prévio examinou os efeitos hemodinâmicos agudos desta enzima. Nós verificamos os efeitos da MMP-2 recombinante humana (rhMMP-2), administrada por via intravenosa (i.v.), a carneiros anestesiados sob condições basais e durante estimulação ?-adrenérgica com dobutamina. Vinte e seis carneiros machos anestesiados foram utilizados em dois protocolos experimentais. Primeiramente, rhMMP-2 (220 ng.kg-1.min-1 durante 60 min) ou salina foi infundida e nenhuma alteração hemodinâmica foi encontrada. No segundo protocolo, infundiu-se dobutamina (5 ?g.kg-1.min-1, i.v., durante 180 min) ou salina em carneiros que haviam recebido a mesma infusão descrita acima de rhMMP-2 ou salina precedida pelo tratamento com doxiciclina (10 mg.kg-1, i.v., durante 15 min) ou salina. Os níveis plasmáticos e cardíacos de MMP-2 foram avaliados por zimografia e a atividade gelatinolítica foi analisada por espectrofluorimetria. Nós observamos que, enquanto a infusão de rhMMP-2 não aumentou os níveis plasmáticos e cardíacos de MMP-2, produziu um aumento na atividade gelatinolítica do coração, e a doxiciclina preveniu este efeito. A dobutamina reduziu o índice de resistência vascular sistêmico (IRVS) e aumentou o índice cardíaco (IC) e a dP/dtmax no ventrículo esquerdo. Entretanto, a co-infusão de rhMMP-2 e dobutamina foi associada com uma menor redução no IRVS e com menores aumentos no IC e na dP/dtmax induzidos pela dobutamina. O pré-tratamento com doxiciclina impediu estas alterações induzidas pela rhMMP-2 na resposta à dobutamina. Adicionalmente, verificou-se que a rhMMP-2 reduziu a formação de AMP cíclico em cardiomiócitos e que os inibidores de MMPs doxiciclina e ONO-4817 impediram esta redução. Nossos resultados mostram que a rhMMP-2, sob condições basais, não exerce efeitos hemodinâmicos em carneiros. Entretanto, a rhMMP-2, sob estimulação cardíaca, prejudica a resposta cardiovascular induzida pela ativação de receptores ?-adrenérgicos / Abstract: Experimental and clinical evidence indicate the involvement of matrix metalloproteinases (MMPs) in the pathogenesis of many disease conditions, including cardiovascular diseases. Particularly, imbalanced MMP-2 activity apparently plays a critical role in hypertension, heart failure and in other alterations of the cardiovascular system. Various studies show many targets unrelated to the extracellular matrix for MMP-2, including intracellular proteins and vasoactive mediators. Additionally, recent studies indicate the involvement of this enzyme in proteolytic cleavage of 'beta'1- and 'beta'2-adrenoreceptors. Although some studies have suggested that MMP-2 may affect the vascular tone and impair 'beta'-adrenoreceptor function, no previous study has examined the acute hemodynamic effects of this enzyme. We examined the effects of recombinant human MMP-2 (rhMMP-2) administered intravenously (i.v.) to anesthetized lambs at baseline conditions and during ?-adrenergic stimulation with dobutamine. Twenty-six anesthetized male lambs were used in two study protocols. Firstly, rhMMP-2 (220 ng.kg-1.min-1 over 60 min) or vehicle was infused and no significant hemodynamic changes were found. In the second protocol, we infused dobutamine (5 ug.kg-1.min-1, i.v., over 180 min) or saline in lambs that had received the same rhMMP-2 infusion preceded by treatment with doxycycline (10 mg.kg-1, i.v., during 15 min) or saline. Plasma and cardiac MMP-2 levels were assessed by gelatin zymography and gelatinolytic activity was assessed by spectrofluorimetry. We found that, while the infusion of rhMMP-2 did not increase plasma and cardiac MMP-2 levels, it increased cardiac gelatinolytic activity, and doxycycline blunted this effect. Dobutamine decreased systemic vascular resistance index (SVRI) and increased the cardiac index (CI) and left ventricular dP/dtmax. However, co-infusion of rhMMP-2 and dobutamine was associated with lower dobutamine-induced decrease in SVRI and with lower dobutamine-induced increase in CI and dP/dtmax. Pre-treatment with doxyxycline blunted rhMMP-2-induced changes in dobutamine responses. Additionally, we found that rhMMP-2 decreased cyclic AMP levels in cardiomyocytes and that tne inhibitors of MMPs doxyxycline and ONO-4817 prevented this reduction. Our findings show that rhMMP-2, at baseline conditions, exerts no major hemodynamic effects in lambs. However, rhMMP-2, during cardiac stimulation, impairs the responses elicited by activation of 'beta'-adrenoreceptors / Doutorado / Farmacologia / Doutora em Farmacologia
13

Avaliação da interação do hormônio tireoidiano com o sistema nervoso simpático, via receptor Beta2-adrenérgico, na regulação da massa e metabolismo ósseos / Evaluation of the interaction of thyroid hormone with the sympathetic nervous system, via beta2-adrenergic receptor, in the regulation of bone mass and metabolism

Papi, Bianca Neofiti 06 August 2018 (has links)
O hormônio tireoidiano (HT) é essencial para o desenvolvimento, maturação e metabolismo ósseos, enquanto que o sistema nervoso simpático (SNS) é, também, um potente regulador do remodelamento ósseo. Demonstrou-se que SNS regula negativamente a massa óssea, agindo via receptores ?2-adrenérgicos (?2-AR), expressos em osteoblastos. O nosso grupo demonstrou que os receptores ?2 adrenérgicos (?2-AR) também medeiam ações do SNS no esqueleto e que são expressos em osteoblastos, osteócitos, condrócitos e osteoclastos. Considerando-se que o HT interage com o SNS para regular uma série de processos fisiológicos, e que o excesso de HT e a ativação do SNS causam perda de massa óssea, levantamos a hipótese de que há interação entre o HT com o SNS para regular a massa óssea. Estudos do nosso grupo vêm sustentando essa hipótese, uma vez que camundongos com inativação gênica dos receptores beta2-AR apresentam resistência à osteopenia induzida por doses tóxicas de HT. Considerando-se, ainda, que a interação do HT com o SNS em vários tecidos e/ou órgãos depende da sinalização beta2 adrenérgica, o presente estudo teve como objetivo avaliar se a interação do HT com o SNS para regular a morfofisiologia óssea envolve o beta2-AR. Para tanto, estudamos o efeito de 10x e 20x a dose fisiológica de triiodotironina (3,5ug ou 7.0ug de T3/100g de massa corporal/dia, respectivamente), por 90 dias, na microaquitetura óssea e em parâmetros biomecânicos do fêmur de camundongos com inativação gênica do beta2-AR (beta2-AR-/-), e nos seus respectivos Selvagens (Selv), os camundongos da linhagem FVB. Como esperado, o tratamento com T3 promoveu efeitos deletérios na microarquitetura trabecular das fêmeas Selv, enquanto alguns desses efeitos foram mais brandos ou inexistentes nos animais beta2-AR-/-, revelando resistência do osso trabecular dos animais knockout (KO) aos efeitos deletérios da tireotoxicose. Em contraste, a microarquitetura femoral dos camundongos machos beta2-AR-/- se mostrou mais sensível aos efeitos deletérios da tireotoxicose, em relação aos respectivos Selv. Quanto ao osso cortical femoral, vimos que o tratamento com T3 aumentou o perímetro endosteal e a área medular nos animais Selv machos e fêmeas, mas não nos animais beta2-AR-/-, o que sugere que o T3 promove reabsorção óssea endosteal no osso cortical, em um mecanismo que depende da via de sinalização do beta2-AR. Vimos, ainda, que o tratamento com T3 causou reduções significativas na carga máxima, tenacidade, rigidez e resiliência do fêmur dos camundongos fêmeas Selv. Em contraste, nenhum desses parâmetros biomecânicos foi afetado pelo tratamento com T3 no fêmur das fêmeas KO, evidenciando, mais uma vez, uma resistência desses animais aos efeitos deletérios da tireotoxicose no tecido ósseo. Por outro lado, os camundongos machos Selv e KO se mostraram resistentes aos efeitos deletérios do tratamento com T3 sobre os parâmetros biomecânicos do fêmur, sugerindo a participação de fatores sexuais na interação do HT com o SNS para regular a morfofisiologia óssea. Em conjunto, os achados do presente estudo corroboram a hipótese de que o HT interage com o SNS através da via dos receptores beta2 adrenérgicos para regular a morfofisiologia óssea, especialmente em fêmeas e no osso cortical / Thyroid hormone (TH) is essential for bone development, maturation and metabolism, while the sympathetic nervous system (SNS) is also a potent regulator of bone remodeling. SNS has been shown to negatively regulate bone mass, acting via beta2-adrenergic (beta2-AR) receptors expressed in osteoblasts. Our group demonstrated that alpha2-adrenergic (alpha2-AR) receptors also mediate SNS actions in the skeleton and are expressed in osteoblasts, osteocytes, chondrocytes and osteoclasts. Considering that TH interacts with the SNS to regulate a series of physiological processes, and that the excess of TH and the activation of the SNS cause loss of bone mass, we hypothesize that there is interaction between TH and the SNS to regulate the bone mass. Studies of our group have supported this hypothesis, since mice with gene inactivation of alpha2-AR present resistance to the osteopenia induced by toxic doses of TH. Considering that the TH-SNS interaction in various tissues and/or organs depends on beta2-adrenergic signaling, the present study aimed to evaluate whether the interaction of TH with the SNS to regulate the bone morphophysiology involves beta2- AR. Therefore, we studied the effect of 10x and 20x the physiological dose of triiodothyronine (3.5ug or 7.0ug of T3/100g body mass/day, respectively), for 90 days, in the bone microarchitecture and biomechanical parameters of the femur mice with beta2-AR gene inactivation (beta2-AR-/-), and of their respective Wild-type (WT) controls, the FVB lineage mice. As expected, T3 treatment promoted deleterious effects on the trabecular microarchitecture of the WT females, while some of these effects were milder or nonexistent in beta2-AR-/- animals, revealing trabecular bone resistance of knockout (KO) animals to the deleterious effects of thyrotoxicosis. In contrast, the femoral microarchitecture of the male beta2-AR-/- mice was more sensitive to the deleterious effects of thyrotoxicosis, in relation to the respective WT animals. Regarding to the femoral cortical bone, we saw that T3 treatment increased the endosteal perimeter and the medullary area both male and female WT animals, but not in the beta2-AR-/- mice, suggesting that T3 promotes endosteal bone resorption in the cortical bone, in a mechanism that depends on the alpha2-AR signaling pathway. We also found that treatment with T3 caused significant reductions in the maximum load, tenacity, stiffness and resilience of femurs of the WT female mice. In contrast, none of these biomechanical parameters was affected by T3 treatment in the KO females, demonstrating again resistance of these animals to the deleterious effects of thyrotoxicosis on bone tissue. On the other hand, WT and KO male mice were resistant to the deleterious effects of T3 treatment on the biomechanical parameters of the femur, suggesting the participation of sexual factors in the interaction of HT with the SNS to regulate bone morphophysiology. Taken together, the findings of the present study corroborate the hypothesis that TH interacts with the SNS through the beta2 adrenergic receptor pathway to regulate bone morphophysiology, especially in females and cortical bone
14

Avaliação do bloqueio simpático cervico-torácico esquerdo por clipagem em portadores de insuficiência cardíaca sistólica sintomática com terapia medicamentosa otimizada / Left sympathetic surgical blockade in systolic heart failure patients with optimal medical therapy

Souza, Germano Emílio Conceição 13 December 2010 (has links)
FUNDAMENTO: A modulação adicional do sistema nervoso simpático em pacientes com insuficiência cardíaca sistólica (ICS) sob tratamento clínico otimizado pode ser benéfica. Objetivo: Avaliar a exequibilidade e segurança do BSCTE em pacientes com ICS sintomática, refratária ao tratamento farmacológico incluindo beta-bloqueadores (BB). Secundariamente, avaliamos os seus efeitos no sistema cardiovascular tanto no perioperatório quanto após seis meses de seguimento. MÉTODOS: Ensaio clínico com duplo sorteio com \"concealed allocation\". Pacientes com ICS e Fração de ejeção do VE (FEVE) = 40%, CF da NYHA II ou III, ritmo sinusal e FC > 65 bpm a despeito do uso adequado de BB foram incluídos. Pacientes com cardiomiopatia chagásica, congênita, valvar e com marcapasso ou comorbidades graves foram excluídos. A cada três pacientes incluídos, era realizado um duplo sorteio com um paciente alocado no grupo controle (G1) e dois pacientes no grupo tratamento (G2). O procedimento consistia em videotoracoscopia esquerda, em posição semi-sentada, com intubação seletiva e sob anestesia geral, com controle de parâmetros hemodinâmicos invasivos nas 24h em UTI. Feita clipagem do 1/3 inferior do gânglio estrelado e do espaço inter-espinhal entre T3 e T4 esquerdos. Critérios previamente estabelecidos de interrupção do estudo e remoção dos clips por via toracoscópica eram morte ou piora grave dos sintomas de IC atribuíveis ao procedimento. Em todos os pacientes, era realizada avaliação clínica, Minnesota Living with Heart Failure Questionnaire (MLHFQ), ecocardiográfica, com Holter de 24h, teste ergoespirométrico, teste de caminhada de 6 minutos, teste de barorreflexo, microneurografia, cintilografia com 123I-metaiodobenzilganidina(MIBG) e ventriculografia radioisotópica(Gated) antes e seis meses após o sorteio. Análise estatística: teste exato de Fischer para proporções; teste t de student não-pareado para variáveis contínuas normais; ANOVA duplo fator quando aplicável. p significativo se < 0,05. RESULTADOS: Entre dezembro 2006 e junho de 2010, 15 pacientes foram consecutivamente selecionados (G1=5 e G2=10). Características de base semelhantes. Não houve eventos adversos no perioperatório. Dois pacientes no G1 foram a óbito e outro paciente evoluiu em choque cardiogênico ao longo do seguimento. No G2, 2 pacientes evoluíram para óbito não atribuível ao procedimento. Houve melhora, no G2, nos seguintes parâmetros: FEVE (25±6.6 vs 33±5.2, p=0.03); teste de caminhada de 6 min (167±35 vs 198±47), p=0.02); Holter 24h- FC média (77±5 vs 72±4, p=0.0003; escore do MLHFQ (48±10 vs 40±14, p=0.01. Não houve mudança nos seguintes parâmetros: relação coração/mediastino tardia pelo MIBG, diâmetro diastólico final do VE, FEVE pelo Gated, atividade simpática periférica, parâmetros do barorreflexo, pico de consumo de oxigênio (VO2), níveis de BNP e SDNN no Holter. CONCLUSÕES: O BSCTE é factível e parece ser seguro em pacientes com ICS sintomáticos em tratamento clínico otimizado. Os seus efeitos benéficos explorados neste estudo necessitam de um ensaio clínico randomizado de maior porte para sua confirmação / BACKGROUND: Sympathetic nervous system modulation is the cornerstone treatment for systolic heart failure (SHF). We sought to evaluate the feasibility, safety and potential beneficial effects of additional surgical sympathetic blockade in SHF patients. METHODS: In this prospective randomised controlled trial, inclusion criteria were: NYHA functional class II or III, left ventricular ejection fraction (LVEF) = 40%, sinus rhythm and resting heart rate >65 bpm, despite optimal medical therapy (MT). Fifteen patients were randomly assigned in a 1:2 basis either to MT alone or MT plus surgical treatment (ST). ST consisted of left lower 1/3 stellar ganglion and T3-T4 thoracic interspinal space videothoracoscopic clipping. Primary endpoints were feasibility and safety. Secondary endpoints were changes in clinical status, exercise capacity, quality of life, LVEF and remodeling by echocardiography and heart rate before and after 6 months of randomisation. RESULTS: 10 patients underwent ST and there were no adverse events attributable to surgery. ST improved: LVEF (25±6.6 vs 33±5.2, p=0.03); 6 -min walking distance in meters (167±35 vs 198±47), p=0.02); 24h-Holter mean HR (77±5 vs 72±4, p=0.0003; MLHFQ score (48±10 vs 40±14, p=0.01. 123IMIBG radionuclide scan heart/mediastinum ratio, LV end diastolic diameter, sympathetic peripheral nerve activity, peak VO2, LVEF by Gated, serum BNP levels and 24h Holter NN standard deviation were unchanged. Two patients died at each group. Clinical status improvement was only observed at ST. CONCLUSIONS: ST was feasible and safe in SHF patients. Its beneficial effects warrant the development of a larger randomized trial
15

Relationship between tumor necrosis factor-alpha and beta-adrenergic receptors in cultured rat astrocytes.

January 2003 (has links)
by Keung Ka Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 163-184). / Abstracts in English and Chinese. / Abstract --- p.ii / 摘要 --- p.iv / Acknowledgements --- p.vi / Table of Contents --- p.vii / List of Abbreviations --- p.xiv / List of Tables --- p.xvi / List of Figures --- p.xvi / Chapter CHAPTER 1. --- INTRODUCTION / Chapter 1.1. --- Events happened after brain injury --- p.1 / Chapter 1.2. --- Glial cells --- p.3 / Chapter 1.2.1. --- Microglia --- p.4 / Chapter 1.2.2. --- Oligodendrocytes --- p.5 / Chapter 1.2.3. --- Astrocytes --- p.5 / Chapter 1.2.3.1. --- Uptake of neurotransmitters --- p.7 / Chapter 1.2.3.2. --- Maintenance of extracellular homeostasis --- p.8 / Chapter 1.2.3.3. --- Induction of blood-brain-barrier --- p.8 / Chapter 1.2.3.4. --- Guidance of migrating neurons during development --- p.9 / Chapter 1.2.3.5. --- Immunocompetent cells of the brain --- p.9 / Chapter 1.2.3.6. --- Contribution to astrogliosis --- p.10 / Chapter 1.3. --- Cytokines and astrogliosis --- p.11 / Chapter 1.3.1. --- IL-6 and astrogliosis --- p.12 / Chapter 1.3.2. --- IL-1 and astrogliosis --- p.13 / Chapter 1.3.3. --- IFN-γ and astrogliosis --- p.14 / Chapter 1.3.4. --- TNF-α and astrogliosis --- p.14 / Chapter 1.3.4.1. --- General properties of TNF-α --- p.15 / Chapter 1.3.4.2. --- TNF receptors (TNFRs) --- p.17 / Chapter 1.3.4.3. --- NFkB induction --- p.18 / Chapter 1.3.4.4. --- Intermediate early genes --- p.19 / Chapter 1.3.4.5. --- iNOS is the target of NFkB and AP-1 --- p.20 / Chapter 1.4. --- β-Adrenergic receptors (P-ARs) --- p.21 / Chapter 1.4.1. --- β-ARs and astrogliosis --- p.22 / Chapter 1.4.2. --- General properties of β-ARs --- p.23 / Chapter 1.4.3. --- Interactions between β-adrenergic mechanism and TNF-α --- p.24 / Chapter 1.5. --- Aims and scopes of the project --- p.25 / Chapter CHAPTER 2. --- MATERIALS & METHODS / Chapter 2.1. --- Materials --- p.29 / Chapter 2.1.1. --- Rats for astrocyte culture --- p.29 / Chapter 2.1.2. --- Cell culture materials --- p.29 / Chapter 2.1.2.1. --- Complete Dulbecco's Modified Eagle Medium:F12 (DF12) --- p.29 / Chapter 2.1.2.2. --- Phosphate buffered saline (PBS) --- p.30 / Chapter 2.1.3. --- Drugs preparation --- p.30 / Chapter 2.1.3.1. --- Recombinant cytokines --- p.30 / Chapter 2.1.3.2. --- Modulators of protein kinase A (PKA) --- p.30 / Chapter 2.1.3.3. --- Modulators of protein kinase C (PKC) --- p.31 / Chapter 2.1.3.4. --- β-Agonists and -antagonists --- p.31 / Chapter 2.1.3.5. --- Antibodies used in western blot analysis --- p.31 / Chapter 2.1.4. --- Reagents for cell proliferation determination --- p.32 / Chapter 2.1.5. --- Reagents for RNA isolation --- p.32 / Chapter 2.1.6. --- Reagents for reverse transcription-polymerase chain reaction (RT-PCR) --- p.32 / Chapter 2.1.7. --- Reagents for Electrophoresis --- p.33 / Chapter 2.1.8. --- Reagents and buffers for western blotting --- p.35 / Chapter 2.2. --- Methods --- p.36 / Chapter 2.2.1. --- Preparation of primary astrocytes --- p.36 / Chapter 2.2.2. --- Preparation of cells for assays --- p.36 / Chapter 2.2.3. --- Determination of cell proliferation --- p.36 / Chapter 2.2.3.1. --- [3H]-Thymidine incorporation assay --- p.37 / Chapter 2.2.3.2. --- MTT assay --- p.37 / Chapter 2.2.3.3. --- Data analysis --- p.38 / Chapter 2.2.4. --- Determination of RNA expression by RT-PCR analysis --- p.38 / Chapter 2.2.4.1. --- RNA extraction --- p.38 / Chapter 2.2.4.2. --- Spectrophotometric Quantitation of DNA and RNA --- p.38 / Chapter 2.2.4.3. --- RNA gel electrophoresis --- p.39 / Chapter 2.2.4.4. --- Reverse transcription-polymerase chain reaction (RT-PCR) --- p.39 / Chapter 2.2.4.5. --- Separation of PCR products by agarose gel electrophoresis --- p.40 / Chapter 2.2.4.6. --- Quantification of band density --- p.41 / Chapter 2.2.5. --- Determination of protein expression by Western blotting --- p.41 / Chapter 2.2.5.1. --- Total protein extraction --- p.41 / Chapter 2.2.5.2. --- Western blotting analysis --- p.42 / Chapter CHAPTER 3. --- RESULTS / Chapter 3.1. --- Effects of pro-inflammatory cytokines on astrocyte proliferation --- p.43 / Chapter 3.1.1. --- Effects of TNF-α on astrocyte proliferation --- p.44 / Chapter 3.1.2. --- Effects of TNF-R1 and -R2 antibodies on astrocyte proliferation --- p.47 / Chapter 3.1.3. --- Effects of other cytokines on astrocyte proliferation --- p.50 / Chapter 3.1.4. --- Comparisons of the effects of cytokines on astrocyte proliferation --- p.53 / Chapter 3.2. --- Effects of β-agonist and -antagonist on astrocyte proliferation --- p.55 / Chapter 3.3. --- Effects of TNF-α on the expression of TNFR and endogenous TNF-α in astrocytes --- p.60 / Chapter 3.3.1. --- Effects of TNF-α on the expression of TNF-R1 and -R2 in astrocytes --- p.60 / Chapter 3.3.1.1. --- Effects of TNF-α on the expression of TNF-R1 and -R2 mRNA --- p.60 / Chapter 3.3.1.2. --- TNFR subtypes involved in the TNF-α-induced TNF-R2 mRNA expression --- p.62 / Chapter 3.3.1.3. --- Signaling pathways of the TNF-α-induced TNF-R2 mRNA expression --- p.67 / Chapter 3.3.1.4. --- Effects of TNF-α on the expression of TNF-R1 and -R2 --- p.68 / Chapter 3.3.2. --- Effects of TNF-α on the expression of endogenous TNF-α in astrocytes --- p.73 / Chapter 3.3.2.1. --- Effects of TNF-α on the expression of TNF-α mRNA --- p.73 / Chapter 3.3.2.2. --- TNFR subtypes involved in the TNF-α-induced TNF-α mRNA expression --- p.73 / Chapter 3.3.2.3. --- Signaling pathways of the TNF-α-induced TNF-α mRNA expression --- p.74 / Chapter 3.3.2.4. --- Effects of other cytokines on the expression of TNF-α mRNA --- p.75 / Chapter 3.4. --- Effects of TNF-α on the expression of β1- and β2-AR in astrocytes --- p.85 / Chapter 3.4.1. --- Effects of TNF-α on the expression of β1- and β2-AR mRNA --- p.85 / Chapter 3.4.2. --- TNFR subtypes involved in the TNF-a-induced β1 and β2-AR mRNA expressions --- p.88 / Chapter 3.4.3. --- Signaling pathways of the TNF-α -induced β1- and β2-AR mRNA expressions --- p.88 / Chapter 3.4.4. --- Effects of TNF-α on the expression of β1- and β2-AR protein --- p.100 / Chapter 3.4.5. --- Effects of other cytokines on the expression of β1- and β2-AR mRNA --- p.100 / Chapter 3.5. --- Interactions between TNF-α and β-adrenergic mechanism in astrocytes --- p.107 / Chapter 3.5.1. --- Effects of β-agonists and -antagonists on the TNF-α-induced endogenous TNF-α expression in astrocytes --- p.107 / Chapter 3.5.1.1. --- Effects of ISO and PROP on the expression of TNF-α mRNA --- p.107 / Chapter 3.5.1.2. --- β-AR subtypes involved in the TNF-α-induced TNF-α mRNA expression --- p.108 / Chapter 3.5.2. --- Effects of β-agonists and -antagonists on the TNF-α-induced TNFRs expression in astrocytes --- p.112 / Chapter 3.5.2.1. --- Effects of ISO and PROP on the expression of TNFRs mRNA --- p.112 / Chapter 3.5.2.2. --- β-AR subtypes involved in the TNF-α-induced TNF-R2 mRNA expression --- p.115 / Chapter 3.6. --- Effects of TNF-α on the expression of transcription factors in astrocytes --- p.117 / Chapter 3.6.1. --- "Effects of TNF-α on c-fos, c-jun and NFKB/p50 expression" --- p.118 / Chapter 3.6.2. --- Effects of other cytokines on the expression of NFKB/p50 mRNA --- p.119 / Chapter 3.6.3. --- "TNFR subtypes involved in the TNF-α-induced c-fos, c-jun and NFKB/p50 mRNA expression" --- p.125 / Chapter 3.7. --- Effects of TNF-α on the expression of iNOS in astrocytes --- p.130 / Chapter 3.7.1. --- Effects ofTNF-α the expression of iNOS mRNA --- p.130 / Chapter 3.7.2. --- TNFR subtypes involved in the TNF-α-induced iNOS mRNA expression --- p.131 / Chapter 3.7.3. --- Signaling pathways of the TNF-α-induced iNOS mRNA expression --- p.136 / Chapter 3.7.4. --- Effects of other cytokines on the expression of iNOS mRNA --- p.139 / Chapter 3.7.5. --- Effects of β-agonists and -antagonists on the TNF-α-induced iNOS expression --- p.142 / Chapter 3.7.5.1. --- Effects of ISO and PROP on the expression of iNOS mRNA --- p.142 / Chapter 3.7.5.2. --- β-AR subtypes involved in the TNF-α-induced iNOS mRNA expression --- p.143 / Chapter CHAPTER 4. --- DISCUSSIONS & CONCLUSIONS / Chapter 4.1. --- Effects of TNF-α on astrocyte proliferation --- p.148 / Chapter 4.2. --- Roles of endogenous TNF-α and TNFR in astrocyte proliferation --- p.150 / Chapter 4.3. --- Interactions between TNF-α and β-adrenergic mechanism in astrocytes --- p.154 / Chapter 4.4. --- Induction of transcription factors by TNF-α in astrocytes --- p.157 / Chapter 4.5. --- Possible source of β-agonists --- p.159 / Chapter 4.6. --- Conclusions --- p.160 / REFERENCE --- p.163
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Avaliação da interação do hormônio tireoidiano com o sistema nervoso simpático, via receptor Beta2-adrenérgico, na regulação da massa e metabolismo ósseos / Evaluation of the interaction of thyroid hormone with the sympathetic nervous system, via beta2-adrenergic receptor, in the regulation of bone mass and metabolism

Bianca Neofiti Papi 06 August 2018 (has links)
O hormônio tireoidiano (HT) é essencial para o desenvolvimento, maturação e metabolismo ósseos, enquanto que o sistema nervoso simpático (SNS) é, também, um potente regulador do remodelamento ósseo. Demonstrou-se que SNS regula negativamente a massa óssea, agindo via receptores ?2-adrenérgicos (?2-AR), expressos em osteoblastos. O nosso grupo demonstrou que os receptores ?2 adrenérgicos (?2-AR) também medeiam ações do SNS no esqueleto e que são expressos em osteoblastos, osteócitos, condrócitos e osteoclastos. Considerando-se que o HT interage com o SNS para regular uma série de processos fisiológicos, e que o excesso de HT e a ativação do SNS causam perda de massa óssea, levantamos a hipótese de que há interação entre o HT com o SNS para regular a massa óssea. Estudos do nosso grupo vêm sustentando essa hipótese, uma vez que camundongos com inativação gênica dos receptores beta2-AR apresentam resistência à osteopenia induzida por doses tóxicas de HT. Considerando-se, ainda, que a interação do HT com o SNS em vários tecidos e/ou órgãos depende da sinalização beta2 adrenérgica, o presente estudo teve como objetivo avaliar se a interação do HT com o SNS para regular a morfofisiologia óssea envolve o beta2-AR. Para tanto, estudamos o efeito de 10x e 20x a dose fisiológica de triiodotironina (3,5ug ou 7.0ug de T3/100g de massa corporal/dia, respectivamente), por 90 dias, na microaquitetura óssea e em parâmetros biomecânicos do fêmur de camundongos com inativação gênica do beta2-AR (beta2-AR-/-), e nos seus respectivos Selvagens (Selv), os camundongos da linhagem FVB. Como esperado, o tratamento com T3 promoveu efeitos deletérios na microarquitetura trabecular das fêmeas Selv, enquanto alguns desses efeitos foram mais brandos ou inexistentes nos animais beta2-AR-/-, revelando resistência do osso trabecular dos animais knockout (KO) aos efeitos deletérios da tireotoxicose. Em contraste, a microarquitetura femoral dos camundongos machos beta2-AR-/- se mostrou mais sensível aos efeitos deletérios da tireotoxicose, em relação aos respectivos Selv. Quanto ao osso cortical femoral, vimos que o tratamento com T3 aumentou o perímetro endosteal e a área medular nos animais Selv machos e fêmeas, mas não nos animais beta2-AR-/-, o que sugere que o T3 promove reabsorção óssea endosteal no osso cortical, em um mecanismo que depende da via de sinalização do beta2-AR. Vimos, ainda, que o tratamento com T3 causou reduções significativas na carga máxima, tenacidade, rigidez e resiliência do fêmur dos camundongos fêmeas Selv. Em contraste, nenhum desses parâmetros biomecânicos foi afetado pelo tratamento com T3 no fêmur das fêmeas KO, evidenciando, mais uma vez, uma resistência desses animais aos efeitos deletérios da tireotoxicose no tecido ósseo. Por outro lado, os camundongos machos Selv e KO se mostraram resistentes aos efeitos deletérios do tratamento com T3 sobre os parâmetros biomecânicos do fêmur, sugerindo a participação de fatores sexuais na interação do HT com o SNS para regular a morfofisiologia óssea. Em conjunto, os achados do presente estudo corroboram a hipótese de que o HT interage com o SNS através da via dos receptores beta2 adrenérgicos para regular a morfofisiologia óssea, especialmente em fêmeas e no osso cortical / Thyroid hormone (TH) is essential for bone development, maturation and metabolism, while the sympathetic nervous system (SNS) is also a potent regulator of bone remodeling. SNS has been shown to negatively regulate bone mass, acting via beta2-adrenergic (beta2-AR) receptors expressed in osteoblasts. Our group demonstrated that alpha2-adrenergic (alpha2-AR) receptors also mediate SNS actions in the skeleton and are expressed in osteoblasts, osteocytes, chondrocytes and osteoclasts. Considering that TH interacts with the SNS to regulate a series of physiological processes, and that the excess of TH and the activation of the SNS cause loss of bone mass, we hypothesize that there is interaction between TH and the SNS to regulate the bone mass. Studies of our group have supported this hypothesis, since mice with gene inactivation of alpha2-AR present resistance to the osteopenia induced by toxic doses of TH. Considering that the TH-SNS interaction in various tissues and/or organs depends on beta2-adrenergic signaling, the present study aimed to evaluate whether the interaction of TH with the SNS to regulate the bone morphophysiology involves beta2- AR. Therefore, we studied the effect of 10x and 20x the physiological dose of triiodothyronine (3.5ug or 7.0ug of T3/100g body mass/day, respectively), for 90 days, in the bone microarchitecture and biomechanical parameters of the femur mice with beta2-AR gene inactivation (beta2-AR-/-), and of their respective Wild-type (WT) controls, the FVB lineage mice. As expected, T3 treatment promoted deleterious effects on the trabecular microarchitecture of the WT females, while some of these effects were milder or nonexistent in beta2-AR-/- animals, revealing trabecular bone resistance of knockout (KO) animals to the deleterious effects of thyrotoxicosis. In contrast, the femoral microarchitecture of the male beta2-AR-/- mice was more sensitive to the deleterious effects of thyrotoxicosis, in relation to the respective WT animals. Regarding to the femoral cortical bone, we saw that T3 treatment increased the endosteal perimeter and the medullary area both male and female WT animals, but not in the beta2-AR-/- mice, suggesting that T3 promotes endosteal bone resorption in the cortical bone, in a mechanism that depends on the alpha2-AR signaling pathway. We also found that treatment with T3 caused significant reductions in the maximum load, tenacity, stiffness and resilience of femurs of the WT female mice. In contrast, none of these biomechanical parameters was affected by T3 treatment in the KO females, demonstrating again resistance of these animals to the deleterious effects of thyrotoxicosis on bone tissue. On the other hand, WT and KO male mice were resistant to the deleterious effects of T3 treatment on the biomechanical parameters of the femur, suggesting the participation of sexual factors in the interaction of HT with the SNS to regulate bone morphophysiology. Taken together, the findings of the present study corroborate the hypothesis that TH interacts with the SNS through the beta2 adrenergic receptor pathway to regulate bone morphophysiology, especially in females and cortical bone
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Avaliação do bloqueio simpático cervico-torácico esquerdo por clipagem em portadores de insuficiência cardíaca sistólica sintomática com terapia medicamentosa otimizada / Left sympathetic surgical blockade in systolic heart failure patients with optimal medical therapy

Germano Emílio Conceição Souza 13 December 2010 (has links)
FUNDAMENTO: A modulação adicional do sistema nervoso simpático em pacientes com insuficiência cardíaca sistólica (ICS) sob tratamento clínico otimizado pode ser benéfica. Objetivo: Avaliar a exequibilidade e segurança do BSCTE em pacientes com ICS sintomática, refratária ao tratamento farmacológico incluindo beta-bloqueadores (BB). Secundariamente, avaliamos os seus efeitos no sistema cardiovascular tanto no perioperatório quanto após seis meses de seguimento. MÉTODOS: Ensaio clínico com duplo sorteio com \"concealed allocation\". Pacientes com ICS e Fração de ejeção do VE (FEVE) = 40%, CF da NYHA II ou III, ritmo sinusal e FC > 65 bpm a despeito do uso adequado de BB foram incluídos. Pacientes com cardiomiopatia chagásica, congênita, valvar e com marcapasso ou comorbidades graves foram excluídos. A cada três pacientes incluídos, era realizado um duplo sorteio com um paciente alocado no grupo controle (G1) e dois pacientes no grupo tratamento (G2). O procedimento consistia em videotoracoscopia esquerda, em posição semi-sentada, com intubação seletiva e sob anestesia geral, com controle de parâmetros hemodinâmicos invasivos nas 24h em UTI. Feita clipagem do 1/3 inferior do gânglio estrelado e do espaço inter-espinhal entre T3 e T4 esquerdos. Critérios previamente estabelecidos de interrupção do estudo e remoção dos clips por via toracoscópica eram morte ou piora grave dos sintomas de IC atribuíveis ao procedimento. Em todos os pacientes, era realizada avaliação clínica, Minnesota Living with Heart Failure Questionnaire (MLHFQ), ecocardiográfica, com Holter de 24h, teste ergoespirométrico, teste de caminhada de 6 minutos, teste de barorreflexo, microneurografia, cintilografia com 123I-metaiodobenzilganidina(MIBG) e ventriculografia radioisotópica(Gated) antes e seis meses após o sorteio. Análise estatística: teste exato de Fischer para proporções; teste t de student não-pareado para variáveis contínuas normais; ANOVA duplo fator quando aplicável. p significativo se < 0,05. RESULTADOS: Entre dezembro 2006 e junho de 2010, 15 pacientes foram consecutivamente selecionados (G1=5 e G2=10). Características de base semelhantes. Não houve eventos adversos no perioperatório. Dois pacientes no G1 foram a óbito e outro paciente evoluiu em choque cardiogênico ao longo do seguimento. No G2, 2 pacientes evoluíram para óbito não atribuível ao procedimento. Houve melhora, no G2, nos seguintes parâmetros: FEVE (25±6.6 vs 33±5.2, p=0.03); teste de caminhada de 6 min (167±35 vs 198±47), p=0.02); Holter 24h- FC média (77±5 vs 72±4, p=0.0003; escore do MLHFQ (48±10 vs 40±14, p=0.01. Não houve mudança nos seguintes parâmetros: relação coração/mediastino tardia pelo MIBG, diâmetro diastólico final do VE, FEVE pelo Gated, atividade simpática periférica, parâmetros do barorreflexo, pico de consumo de oxigênio (VO2), níveis de BNP e SDNN no Holter. CONCLUSÕES: O BSCTE é factível e parece ser seguro em pacientes com ICS sintomáticos em tratamento clínico otimizado. Os seus efeitos benéficos explorados neste estudo necessitam de um ensaio clínico randomizado de maior porte para sua confirmação / BACKGROUND: Sympathetic nervous system modulation is the cornerstone treatment for systolic heart failure (SHF). We sought to evaluate the feasibility, safety and potential beneficial effects of additional surgical sympathetic blockade in SHF patients. METHODS: In this prospective randomised controlled trial, inclusion criteria were: NYHA functional class II or III, left ventricular ejection fraction (LVEF) = 40%, sinus rhythm and resting heart rate >65 bpm, despite optimal medical therapy (MT). Fifteen patients were randomly assigned in a 1:2 basis either to MT alone or MT plus surgical treatment (ST). ST consisted of left lower 1/3 stellar ganglion and T3-T4 thoracic interspinal space videothoracoscopic clipping. Primary endpoints were feasibility and safety. Secondary endpoints were changes in clinical status, exercise capacity, quality of life, LVEF and remodeling by echocardiography and heart rate before and after 6 months of randomisation. RESULTS: 10 patients underwent ST and there were no adverse events attributable to surgery. ST improved: LVEF (25±6.6 vs 33±5.2, p=0.03); 6 -min walking distance in meters (167±35 vs 198±47), p=0.02); 24h-Holter mean HR (77±5 vs 72±4, p=0.0003; MLHFQ score (48±10 vs 40±14, p=0.01. 123IMIBG radionuclide scan heart/mediastinum ratio, LV end diastolic diameter, sympathetic peripheral nerve activity, peak VO2, LVEF by Gated, serum BNP levels and 24h Holter NN standard deviation were unchanged. Two patients died at each group. Clinical status improvement was only observed at ST. CONCLUSIONS: ST was feasible and safe in SHF patients. Its beneficial effects warrant the development of a larger randomized trial
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Tumor suppressive effects of the Beta-2 adrenergic receptor and the small GTPase RhoB

Carie, Adam E. January 2008 (has links)
Dissertation (Ph.D.)--University of South Florida, 2008. / Title from PDF of title page. Document formatted into pages; contains 201 pages. Includes vita. Includes bibliographical references.

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