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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.
241

O crescimento cístico renal é o principal determinante para o desenvolvimento de hipertensão e déficit de concentração em camundongos com deficiência do gene Pkd1 / Renal cyst growth is the main determinant for the development of hypertension and concentration deficit in Pkd1-deficient mice

Jonathan Mackowiak da Fonseca 13 November 2012 (has links)
O desenvolvimento de hipertensão arterial (HAS) ocorre dez anos mais cedo em pacientes com doença renal policística autossômica dominante (DRPAD) comparados à população geral, estando presente em ~60% dos indivíduos afetados antes da perda de função renal. Déficit de concentração renal também se constitui em um achado precoce nesses pacientes. Atualmente se propõe que o sistema renina angiotensina desempenhe um papel central na HAS relacionada à DRPAD, enquanto diferentes explicações têm sido levantadas para justificar o defeito de concentração. Realizamos um cruzamento envolvendo um alelo floxed de Pkd1 com uma linhagem com expressão de nestina-Cre, de modo a gerar camundongos machos císticos viáveis (Pkd1cond/cond:Balcre, CI) com TFG preservada. Estes animais foram avaliados sistematicamente para uma série de parâmetros renais funcionais, morfológicos, celulares e moleculares. Análises paralelas foram conduzidas em camundongos haploinsuficientes para Pkd1 (Pkd1+/-, HT), os quais não desenvolvem cistos renais visíveis. Camundongos CI mostraram-se significantemente hipertensos na idade de 10-13 semanas, um fenótipo não observado em controles não císticos (Pkd1cond/cond, NC) e em animais haploinsuficientes para Pkd1. As frações de excreção de Na+ e K+ mostraram-se reduzidas e a concentração sérica de uréia discretamente elevada em camundongos CI, sugerindo reabsorção tubular de solutos aumentada. A expressão gênica de angiotensinogênio foi significantemente maior em rins CI que NC, enquanto análises imunoistoquímicas revelaram expressão da enzima conversora de angiotensina e do receptor AT1 em epitélio cístico renal. A excreção urinária de NO2 também se mostrou diminuída em camundongos CI, acompanhando-se de taxas aumentadas de proliferação celular e apoptose renais. A osmolalidade urinária máxima foi mais baixa em animais CI, um déficit não encontrado nos controles HT e NC. Interessantemente, uma tendência de níveis plasmáticos mais elevados de vasopressina foi observada em camundongos CI. Tomados em conjunto, esses resultados apoiam a hipótese de que a formação e o crescimento de cistos desempenham um papel importante no desenvolvimento de HAS na DRPAD e de que a ativação do sistema renina-angiotensina intrarrenal constitui-se em um mecanismo fundamental nesse processo. Nossos achados também sugerem fortemente que a expansão cística seja essencial para o desenvolvimento do déficit de concentração renal nessa doença, e são consistentes com a existência de áreas focais de compressão vascular e perfusão diminuída em rins com DRPAD. / Hypertension (SAH) develops ten years earlier in autosomal dominant polycystic kidney disease (ADPKD) patients compared with the general population, being present in ~60% of affected individuals before the loss of renal function. Renal concentrating deficit is also an early finding in these patients. It has been proposed that the renin-angiotensin system plays a central role in ADPKD-related SAH, while different explanations have been raised to justify the concentrating impairment. We bred a floxed allele of Pkd1 with a nestin Cre expressing line to generate viable, adult male cystic mice (Pkd1cond/cond:Balcre, CY) with preserved GFR. These animals were systematically evaluated for a series of renal functional, morphological, cellular and molecular parameters. Parallel analyses were carried out in Pkd1-haploinsuficient mice (Pkd1+/-, HT), which do not develop visible renal cysts. CY mice were significantly hypertensive by 10-13 weeks of age, a phenotype not seen in non-cystic controls (Pkd1cond/cond, NC) and Pkd1-haploinsufficient animals. The fractional excretion of Na+ and K+ were reduced and SUN slightly elevated in the CY mice, suggesting increased tubular solute reabsorption. Angiotensinogen gene expression was significantly higher in CY than NC kidneys, whereas immunohistochemical analyses revealed angiotensin-converting enzyme and AT1 receptor expression in renal cyst epithelia. Urine excretion of NO2 was also diminished in CY mice, along with increased rates of renal cell proliferation and apoptosis. Maximum urine osmolality was decreased in CY animals, a deficit not found in HT and NC controls. Interestingly, a trend toward increased serum vasopressin levels was observed in the CY mice. Taken together these results support the hypothesis that cyst formation and growth play an important role in the development of SAH in ADPKD and that activation of the intrarenal reninangiotensin system is a fundamental mechanism in this process. Our findings also strongly suggest that renal cyst expansion is essential for the development of renal concentrating deficit in this disease, and are consistent with the existence of focal areas of vascular compression and reduced perfusion in ADPKD kidneys.
242

Camundongos com deficiência em Pkd1 apresentam  disfunção cardíaca, fenótipo atenuado por knockout de galectina-3 / Cardiac dysfunction in Pkd1-deficient mice and phenotype rescue by galectin-3 knockout

Bruno Eduardo Pedroso Balbo 16 September 2014 (has links)
Anormalidades miocárdicas destacam-se entre as manifestações cardiovasculares da doença renal policística autossômica dominante (DRPAD). Para investigar a patogênese dessas manifestações, analisamos o fenótipo cardíaco em camundongos com diferentes perfis de deficiência de Pkd1. Avaliamos o modelo Pkd1cond/cond:Nestincre (CI), com cistos renais e hipertensão, na idade de 20-24 semanas, e heterozigotos para mutação nula em Pkd1 (Pkd1+/-; HT) entre 10-13 semanas, representando um modelo não cístico de haploinsuficiência gênica. Animais Pkd1cond/cond (não cístico; NC) e Pkd1+/+ (selvagem, SV) foram usados como controles. Análises ecocardiográficas de camundongos CI e HT revelaram diminuição da fração de ejeção do ventrículo esquerdo, indicando disfunção sistólica. A relação E/A e o tempo de desaceleração foram consistentes com disfunção diastólica em animais CI. Ecocardiografia por speckle-tracking mostrou redução na deformidade cardíaca (strain) nos modelos CI e HT. Os corações de ambos os grupos apresentaram índices de apoptose maiores e fibrose discreta. Neste cenário, investigamos galectina-3 (Gal-3) como modificador potencial do fenótipo cardíaco na DRPAD. Duplos-mutantes Pkd1cond/cond:Nestincre;Lgals3-/- (CIG-) e Pkd1+/- ;Lgals3-/- (HTG-) cursaram com melhora da função sistólica e de strain comparados a CIs e HTs, não diferindo de NCs e SVs. Animais HTG- apresentaram melhora parcial da função diastólica. Apoptose e fibrose cardíaca mostraram-se reduzidas em CIG-s e HTG-s, alcançando valores similares a NCs e SVs. Análises de western blot revelaram expressão de Gal-3 maior em corações CIs que NCs, porém o mesmo não ocorreu entre HTs e SVs. Os duplos-mutantes não apresentaram diferença na ureia sérica quando comparados a CIs e HTs, assim como nas frações de excreção de Na+, Cl- e K+. Por fim, empregamos um modelo renal cístico grave, homozigoto para um alelo que impede a clivagem da policistina-1 no sítio GPS (Pkd1V/V; VV), e mostramos que a ausência de galectina-3 aumentou a sobrevida em animais Pkd1V/V;Lgals3-/- (VVG-). Nossos resultados demonstram disfunção e alterações de deformidade miocárdica em diferentes modelos de deficiência de Pkd1, à semelhança da DRPAD humana, e revelam que knockout de Gal-3 resgata significativamente este fenótipo / Myocardial abnormalities stand out among ADPKD cardiovascular manifestations. To elucidate their pathogenesis, we analyzed the cardiac phenotype in distinct models of Pkd1-deficiency. We evaluated Pkd1cond/cond:Nestincre (CY) cystic, hypertensive mice at 20-24 weeks of age, and Pkd1+/- (HT) noncystic mice at 10-13 weeks, a model of gene haploinsufficiency. Pkd1cond/cond (noncystic; NC) and Pkd1+/+ (wild type, WT) animals were used as controls. Echocardiographic analyses in CY and HT mice revealed decreased left ventricle ejection fraction (LVEF), indicating systolic dysfunction, as well as E/A ratios and deceleration times consistent with diastolic dysfunction in CY animals. Speckle-tracking echocardiography showed reduced cardiac deformability in both models. CY and HT hearts presented higher apoptotic rates and mild fibrosis. In this scenario, we investigated galectin-3 (Gal-3) as a potential modifier of the ADPKD cardiac phenotype. Double mutants Pkd1cond/cond:Nestincre;Lgals3-/- (CYG-) and Pkd1+/-;Lgals3-/- (HTG-) displayed improved systolic and deformability parameters compared to single mutants, while such values did not differ from NCs and WTs. HTG-s presented a partial improvement in diastolic function. CYG- and HTG- hearts showed decreased apoptosis and fibrosis, reaching NC and WT baselines. Western blot analyses revealed higher Gal-3 expression in CY than NC hearts but no difference between HT and WT mice. CYG- and HTG- animals showed no difference in BUN and in the fractional excretion of Na+, Cl- and K+ compared to CYs and HTs. We also employed a more severe renal cystic model, homozygous for an allele that hinders polycystin-1 cleavage at the GPS site (Pkd1V/V; VV), and showed that Pkd1V/V;Lgals3-/- mice present longer survival than VVs. Our findings demonstrate myocardial dysfunction and abnormal deformability in different Pkd1-deficient models, reproducing human ADPKD, and reveals that Gal-3 knockout significantly rescues this phenotype
243

"Efeitos renais da haploinsuficiência do gene Pkd1 (Polycystic kidney disease 1) em camundongos" / Renal effects of Pkd1 gene haploinsufficiency in mice

Mauri Félix de Sousa 19 October 2005 (has links)
Vários estudos mostram que na doença renal policística autossômica dominante os cistos surgem a partir de um mecanismo de "dois-golpes". A patogênese das manifestações não-císticas, contudo, é pouco compreendida. Neste estudo usamos uma linhagem de camundongos endogâmica com uma mutação nula em Pkd1, onde animais heterozigotos apresentam formação cística renal mínima até 40 semanas de idade. O clearance de inulina e o número de glomérulos foram menores em machos Pkd1+/- que Pkd1+/+, enquanto o volume glomerular médio foi maior em heterozigotos. A excreção urinária de NO2/NO3 não diferiu significantemente entre os dois grupos. Avaliamos a osmolalidade urinária máxima em machos e fêmeas Pkd1+/- and Pkd1+/+, porém não foi detectada diferença significante entre os grupos heterozigoto e selvagem. Nossos resultados oferecem evidência direta de que a haploinsuficiência de Pkd1 resulta em anormalidades anatômicas e funcionais renais e sugerem que o estado haploinsuficiente de Pkd1 possa resultar na redução do número de néfrons por diminuir a ramificação tubular renal durante a nefrogênese / Several studies show that in autosomal dominant polycystic kidney disease cysts arise through a "two-hit" mechanism. The pathogenesis of non-cystic features, however, is poorly understood. In this study we used an inbred mouse line with a null mutation of Pkd1, where heterozygotes had minimal renal cyst formation up to 40 weeks of age. Inulin clearance and the number of glomeruli were lower in Pkd1+/- than in Pkd1+/+ males, while a higher average glomerular volume was observed in heterozygotes. The urinary excretion of NO2/NO3 did not significantly differ between the two groups. Maximal urinary osmolality was evaluated in Pkd1+/- and Pkd1+/+ males and females, but no significant difference was detected between the heterozygous and the wild type groups. Our results provide direct evidence that haploinsufficiency for Pkd1 results in anatomic and functional abnormalities of the kidney and suggest that Pkd1 haploinsufficiency may result in a reduced number of nephrons by diminishing renal tubule branching during nephrogenesis
244

A haploinsuficiência de Pkd1 aumenta a lesão renal e induz formação de microcistos após isquemia/reperfusão em camundongos / Pkd1 haploinsufficiency increases renal damage and induces microcyst formation following ischemia/reperfusion in mice

Ana Paula Almeida Bastos 28 July 2010 (has links)
A maior parte dos casos de doença renal policística autossômica dominante (DRPAD) é causada por mutações no gene PKD1 (Polycystic Kidney Disease 1). O insulto por isquemia/reperfusão (IR) constitui-se em uma causa freqüente de lesão renal aguda, incluindo a população de pacientes com DRPAD, mas a relação entre policistina-1 e IR é essencialmente desconhecida. Uma vez que a policistina-1 modula proliferação, diferenciação celular e apoptose em sistemas de cultura de células, sua menor atividade biológica na DRPAD poderia favorecer um maior grau de lesão renal. Utilizamos uma linhagem endogâmica de camundongos 129Sv com uma mutação nula em Pkd1 para testar esta hipótese. Camundongos Pkd1+/- não apresentam cistos renais até 12 semanas de vida, constituindo-se em um modelo puro de haploinsuficiência para este gene. Um insulto IR bilateral de 32 min foi induzido em camundongos machos de 10-12 semanas de idade, heterozigotos e selvagens, por meio do clampeamento reversível de ambos os pedículos renais. Os animais foram analisados 48 h, 7 dias (d) e 14 d após o insulto. Camundongos Pkd1+/- apresentaram FENa, FEK e SCr mais elevadas que animais Pkd1+/+ 48 h após IR. O dano cortical residual foi mais severo em heterozigotos que em selvagens em todos os tempos avaliados. A marcação para PCNA também foi mais alta em camundongos Pkd1+/- que Pkd1+/+ 48 h e 7 d pós-IR, enquanto a taxa de apoptose e a infiltração inflamatória intersticial foram maiores em heterozigotos que em selvagens nos seguimentos de 48 h, 7 d e 14 d pós-IR. A expressão renal de p21 foi menor nos camundongos Pkd1+/- que Pkd1+/+ no tempo de 48 h pós-insulto, tanto no nível transcricional como traducional. Análises adicionais realizadas 6 semanas após o insulto IR revelaram dilatação tubular e formação de microcistos nos camundongos haploinsuficientes para Pkd1, assim como fibrose renal aumentada nesses animais, comparados aos camundongos selvagens. Por fim, um insulto de 35 min de isquemia/reperfusão acompanhou-se de uma mortalidade precoce substancialmente maior nos animais Pkd1+/-. Esses achados sugerem que isquemia/reperfusão induza uma lesão mais severa em rins de camundongos haploinsuficientes para Pkd1, um processo aparentemente dependente de uma deficiência relativa da atividade de p21, assim como dilatação tubular e formação de microcistos. Em conjunto, nossos resultados sugerem que a heterozigose para mutação nula em Pkd1 em camundongo (e talvez em humanos) esteja associada a um risco aumentado para lesão renal por isquemia/reperfusão e a um pior impacto desse insulto sobre a progressão da doença renal. / The majority of autosomal dominant polycystic kidney disease (ADPKD) cases are caused by mutations in the PKD1 gene. Ischemia/reperfusion is a frequent cause of acute kidney injury, including the ADPKD patient population, but the relationship between polycystin-1 and ischemia/reperfusion is essentially unknown. Since polycystin-1 modulates cell proliferation, cell differentiation and apoptosis in cell culture systems, its lower biological activity in ADPKD might amplify the degree of renal injury. Using an inbred 129Sv mouse line with a Pkd1-null mutation, 32-min renal ischemia/reperfusion was induced in 10-12 week-old male non-cystic mice, heterozygotes and wild types. The animals were analyzed at 48h, 7 days (d) and 14d after the insult. Pkd1+/- mice showed higher FENa, FEK and SCr than Pkd1+/+ animals at 48h of follow-up. The residual cortical damage was more severe in heterozygotes than wild types at all evaluated time points. The PCNA staining was also higher in Pkd1+/- than Pkd1+/+ mice at 48h and 7d, while cell apoptotic rates and the interstitial inflammatory infiltration were higher in heterozygotes than wild types at 48h, 7d and 14d postischemia/ reperfusion. The expression of p21 was lower in Pkd1+/- than Pkd1+/+ kidneys at 48h, both at the transcriptional and translational levels. Additional analyses performed 6 weeks after the insult showed tubular dilatation and microcyst formation in the haploinsufficient mice, and increased renal fibrosis in these animals compared to wild types. Thirty-fivemin ischemia/reperfusion, at last, was accompanied by a substantially higher early mortality of Pkd1+/- animals. These findings suggest that ischemia/reperfusion induces a more severe injury in kidneys of Pkd1- haploinsufficient mice, a process that is apparently dependent on a relative deficiency of p21 activity, as well as tubular dilatation and microcyst formation. Altogether, our results suggest that mouse Pkd1-null heterozygosity (and maybe human) is associated with a higher risk for renal ischemia/reperfusion injury and with a worse impact of this insult upon renal disease progression.
245

Efeitos do treinamento físico aeróbio sobre a função sexual em mulheres com síndrome dos ovários policísticos: ensaio clínico controlado / Effects of aerobic exercise training on sexual function in women with polycystic ovary syndrome: a randomized clinical trial

Irís Palma Lopes 05 February 2018 (has links)
Introdução: A Síndrome dos Ovários Policísticos (SOP) é uma doença que acomete de 5 a 10% das mulheres. A SOP tem sido relacionada em alguns estudos à disfunção sexual, ao aumento da ansiedade e depressão e à redução da qualidade de vida. Essas alterações podem estar relacionadas às alterações fenotípicas da SOP como o aumento do peso e das circunferências de quadril e cintura resultantes do hiperandrogenismo. A alteração no estilo de vida, principalmente envolvendo a prática de exercícios físicos, tem sido relevante na melhora das condições de saúde. Até o momento, há poucos estudos avaliando os efeitos do treinamento físico aeróbio sobre a função sexual em mulheres com SOP. Objetivo: Avaliar o efeito do treinamento físico aeróbico na função sexual de mulheres com a Síndrome dos Ovários Policísticos. Métodos: Trata-se de um ensaio clínico controlado com alocação aleatória e randomização estratificada pelo índice de massa corporal (IMC) em 3 grupos paralelos: grupo treinamento aeróbio contínuo (GAC), grupo treinamento aeróbio intermitente (GAI) e grupo controle sem treinamento (GC), sendo GAC com 23 voluntárias, o GAI com 22 voluntárias e o GC com 24 voluntárias. As avaliações ocorreram antes e após o período de 16 semanas de intervenção do treinamento físico aeróbio ou de observação no grupo controle. Foi realizada dosagem plasmática de testosterona, antes e após a intervenção. A função sexual, o risco de ansiedade e depressão e a qualidade de vida foram avaliados respectivamente, por meio dos questionários validados para o Português: Índice de Função Sexual Feminina (IFSF), Escala de Ansiedade e Depressão Hospitalar (HAD), e Questionário de Qualidade de Vida - SF-36. Resultados: Houve diferença significante na RCQ no grupo GAI (p = 0.047) e redução nos níveis de testosterona nos grupos GAC (p < 0.01) e GAI (p = 0.04). Na avaliação do IFSF no GC não houve qualquer alteração antes e após as 16 semanas. Contudo no GAC ocorreu aumento nos escores IFSF total (p = 0.048), satisfação (p = 0.049) e dor (p = 0.03). No GAI foram observados aumentos nos escores: IFSF total (p < 0.01), desejo (p < 0.01), excitação (p < 0.01), lubrificação (p < 0.01), orgasmo (p < 0.01) e satisfação (p = 0.02). Já na avaliação do questionário HAD observou- se diminuição tanto na ansiedade (p = 0.01) e (p < 0.01), quanto na depressão (p < 0.01) e (p = 0.02) nos grupos GAC e GAI respectivamente. Com relação ao SF-36 no GAC foram identificados aumento do escores: aspectos físicos (p = 0.01); estado geral de saúde (p = 0.02); vitalidade (p < 0.01); aspectos sociais (p < 0.01); aspectos emocionais (p = 0.03) e saúde mental (p < 0.01). No GAI houve elevação dos escores: capacidade funcional (p < 0.01); estado geral de saúde (p < 0.01); vitalidade (p < 0.01); aspectos sociais (p < 0.01); aspectos emocionais (p = 0.03) e saúde mental (p < 0.01). Conclusão: Ambos os protocolos de treinamento físico aeróbio foram eficazes na melhora da função sexual, ansiedade e depressão e qualidade de vida, observando maior efetividade no treinamento físico aeróbio intermitente. / Introduction: Polycystic Ovarian Syndrome (PCOS) is a disease that affects 5 to 10% of women. PCOS has been linked in some studies to sexual dysfunction, increased anxiety and depression, and reduced quality of life. These changes may be related to phenotypic changes in PCOS such as increased weight and hip and waist circumferences resulting from hyperandrogenism. The change in lifestyle, mainly involving the practice of physical exercises, has been relevant in improving health conditions. To date, there are few studies evaluating the effects of aerobic exercise training on sexual function in women with PCOS. Objective: To evaluate the effect of aerobic physical training on the sexual function of women with Polycystic Ovarian Syndrome. Methods: This is a controlled clinical trial with random allocation and randomization stratified by body mass index (BMI) in 3 parallel groups: continuous aerobic training group (GAC), intermittent aerobic training group (GAI) and control group without training (GC), GAC with 23 volunteers, GAI with 22 volunteers and GC with 24 volunteers. Evaluations occurred before and after the 16-week intervention period of aerobic or observational physical training in the control group. Testosterone plasma levels were measured before and after the intervention. Sexual function, risk of anxiety and depression, and quality of life were evaluated, respectively, using validated questionnaires for Portuguese: Female Sexual Function Index (IFSF), Hospital Anxiety and Depression Scale (HAD), and Questionnaire Quality of Life - SF-36. Results: There was a significant difference in WHR in the GAI group (p = 0.047) and reduction in testosterone levels in the groups GAC (p <0.01) and GAI (p = 0.04). In the evaluation of IFSF in the CG there was no change before and after 16 weeks. However, in GAC, there was an increase in total IFSF (p = 0.048), satisfaction (p = 0.049) and pain (p = 0.03). GAI showed increases in scores: total IFSF (p <0.01), desire (p <0.01), excitation (p <0.01), lubrication (p <0.01), orgasm (p <0.01) and satisfaction (p = 0.02). In the evaluation of the HAD questionnaire, both anxiety (p = 0.01) and (p <0.01) and depression (p <0.01) and (p = 0.02) in the GAC and GAI groups respectively. Regarding the SF-36 in the GAC was identified increase of the scores: physical aspects (p = 0.01); general health status (p = 0.02); vitality (p <0.01); social aspects (p <0.01); emotional aspects (p = 0.03) and mental health (p <0.01). In GAI there was elevation of the scores: functional capacity (p <0.01); general health status (p <0.01); vitality (p <0.01); social aspects (p <0.01); emotional aspects (p = 0.03) and mental health (p <0.01). Conclusion: Both aerobic physical training protocols were effective in improving sexual function, anxiety and depression and quality of life, observing greater effectiveness in intermittent aerobic physical training.
246

Progression de la maladie rénale chronique et protéinurie : rôle du stress du reticulum endoplasmique et de la lipocaline 2 / Progression of chronic kidney disease proteinuria : role of reticulum stress and endoplasmic lipocalin 2

El Karoui, Khalil 29 November 2012 (has links)
Les maladies rénales chroniques sont devenues un enjeu majeur de santé publique. Qu’elle qu’en soit la cause initiale, la MRC est caractérisée par une réduction néphronique progressive, aboutissant au remplacement des néphrons sains par un tissu fibreux et au déclin de la fonction rénale. Les mécanismes de progression de la MRC sont encore mal compris, mais il a été suggéré que le développement des lésions tubulo-interstitielles joue un rôle essentiel dans le déclin de la fonction rénale. Deux éléments physiopathologiques cruciaux dans le développement de ces lésions sont représentés par (i) l’activation de la voie du récepteur à l’EGF (epidermal growth factor) (EGFR), et (ii) la protéinurie et ses conséquences pour les cellules tubulaires. Les médiateurs communs à ces deux phénomènes ne sont pas connus. Mon travail de thèse a consisté à caractériser une protéine commune à ces deux voies d’activation, ie la lipocaline2 (Lcn2), petite protéine de transport de fer, en étudiant ses voies d'activation et ses conséquences physiopathologiques. Nous montrons que le rôle pathologique de la voie de l’EGFR est gouverné par la surexpression de Lcn2. En effet, dans le contexte de réduction néphronique chirurgicale, (i) les animaux invalidés pour Lcn2 sont protégés du développement des lésions, et (ii) les souris exprimant un dominant négatif de l’EGFR dans le tubule rénal présentent une diminution de l’expression de Lcn2. Nous montrons également que l’invalidation de Lcn2 permet de ralentir la progression de la MRC dans un modèle de polykystose rénale dépendante de l’EGFR, les souris jck (juvenile cystic kidney). Parallèlement, nous montrons que la protéinurie induit également l’expression de Lcn2 dans les cellules tubulaires rénales dans différents modèles expérimentaux. De plus, nous montrons le rôle majeur de Lcn2 dans la progression de la MRC protéinurique, l’invalidation de Lcn2 limitant le développement des lésions rénales et la mortalité des animaux protéinuriques. Si le rôle délétère de Lcn2 est démontré dans différents modèles de néphropathie chronique, nous montrons que les voies moléculaires impliquées dans l’activation de Lcn2 et le rôle de cette protéine dépendent du contexte cellulaire. Nous prouvons que Lcn2 est un médiateur de l'effet mitogénique de l'EGFR, phénomène essentiel de la progression de la MRC, et nous montrons que l’activation de Lcn2 via l’EGFR est dépendante du facteur HIF1α. Cependant, nous démontrons également que l'expression de Lcn2 dans le contexte de protéinurie est dépendante du facteur ATF4 activé par le stress du reticulum endoplasmique (ER), et que Lcn2 est un médiateur de l'apoptose dépendante du stress de l'ER. Enfin, nous prouvons que l’inhibition pharmacologique du stress de l'ER permet une réduction de l’expression de Lcn2 dans les cellules tubulaires, et surtout, un ralentissement du déclin de la fonction rénale des animaux protéinuriques. Nous démontrons également l’importance de ces résultats chez les patients atteints de MRC. Nous identifions NGAL, l'analogue humain de Lcn2, comme un biomarqueur de progression dans la polykystose rénale dominante, et nous montrons qu’elle est fortement surexprimée dans le tissu rénal de patients protéinuriques. L’ensemble de ce travail permet de montrer que Lcn2 est un nouveau médiateur essentiel de multiples néphropathies chroniques. Lcn2 est impliquée dans l’effet mitogénique de l’EGFR ou la réponse apoptotique associée à la protéinurie durant la MRC. Nous ouvrons également de nouvelles perspectives thérapeutiques avec l'utilisation d'inhibiteurs du stress de l'ER dans les néphropathies protéinuriques humaines / Chronic kidney disease (CKD) is now a major public health concern. Whatever the initial kidney injury, CKD is characterized by progressive nephron reduction and kidney function decline. Tubulointerstitial lesions are an essential component of CKD progression, and are mediated by two crucial pathophysiologic elements: epidermal growth factor receptor (EGFR) activation, and proteinuria responsible of tubular cell damage. The aim of this study was to describe a common mediator of both these pathways, ie lipocalin2, an iron carrier protein, by identifying its activation pathways and its pathophysiologic consequences. We show the deleterious effects of the EGFR pathway during nephron reduction is mediated by the activation of Lcn2, which controls the mitogenic effect of EGFR. In fact, after nephron reduction, animals invalidated for Lcn2 are protected from lesions developpement. Moreover, a similar protective effect is seen in jck (juvenile cytic kidney) mice invalidated for Lcn2, a model of polycystic kidney disease EGFR-dependant. Otherwise, we show proteinuria induces Lcn2 expression in tubular cells of different experimental models, and Lcn2 invalidation slows lesion developpement and reduces mortality of proteinuric mice. We demonstrate that the Lcn2 role and activation pathways are dependant of these different models. We show Lcn2 is a mediator of the mitogenic effect of the EGFR, and Lcn2 activation is dependant of HIF1α stabilisation. However, we also show ATF4 is an activator of Lcn2 during endoplasmic reticulum (ER) stress induced by proteinuria in tubular cells. In this context, Lcn2 controls ER stress-induced apoptosis. Pharmacologic inhibition of ER stress in proteinuric animals decreases Lcn2 overexpression, and slows renal function decline. In patients suffering from CKD, we demonstrated NGAL (neutrophil gelatinase-associated lipocalin), the human analog of Lcn2, appears as a critical biomarker of autosomal dominant polycystic kidney disease progression. NGAL is also highly overexpressed in tubular cells in kidney biopsies of proteinuric patients. This work demonstrates Lcn2 is an essential mediator of multiple pathophysiologic components of CKD progression. Moreover, we open new therapeutic perspectives with the use ER stress modulators in proteinuric CKD
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Polykystose rénale autosomique dominante : de la génétique moléculaire au développement d'outils pronostiques / Autosomal dominant holycystic kidney disease (ADPKD) : from molecular genetics to the development of prognostic tools

Cornec-Le Gall, Emilie 10 July 2015 (has links)
La Polykystose Rénale Autosomique Dominante (PKRAD) est une des pathologies héréditaires les plus fréquentes et affecte environ un individu sur 1000. Elle se caractérise par une importante variabilité clinique, notamment dans l’âge de survenue de l’insuffisance rénale terminale. Deux gènes sont en cause : le gène PKD1 situé sur le chromosome 16 (85% des cas) et le gène PKD2 situé sur le chromosome 4 (15% des cas). Les progrès majeurs dans la compréhension des mécanismes moléculaires impliqués ont permis le développement de stratégies thérapeutiques spécifiques, et de nouvelles questions surgissent : quels patients traiter ? Quand débuter les traitements ? La cohorte Genkyst, qui vise à inclure tous les patients suivis pour PKRAD dans la région Grand Ouest, nous a d’abord permis de décrire la variabilité génétique rencontrée dans la PKRAD. Nous avons ensuite démontré l’existence de fortes corrélations génotype-phénotype, en rapportant l’influence sur l’âge de survenue de l’insuffisance rénale terminale non seulement du gène en cause, mais aussi du type de mutation pour le gène PKD1. Enfin, l’analyse des données cliniques et génétiques de 1341 patients nous a permis de développer un algorithme pronostique, baptisé le PROPKD score, permettant de stratifier le risque de progression vers l’insuffisance rénale terminale. Nous espérons que ces travaux participeront à l’individualisation de la prise en charge des patients atteints de PKRAD, ce qui est un enjeu crucial à l’arrivée des nouveaux traitements. / Autosomal Dominant Polycystic Kidney Disease (ADPKD) is one of the most frequent Mendelian inherited disorders, and affects approximately one individual out of 1000. ADPKD is marked by a high clinical variability, especially regarding age at end-stage renal disease (ESRD). Two genes are identified: PKD1 located on the chromosome 16 (85% of the pedigrees) and PKD2 located on the chromosome 4 (15% of the pedigrees). Substantial progress in understanding the cellular mechanisms underlying ADPKD has triggered the development of targeted therapies, and new questions are arising: which patients should be treated? When should we begin these treatments? Thanks to Genkyst cohort, which aims to include all consenting ADPKD patients from the western part of France, we first described the important allelic variability encountered in ADPKD. Secondly, we demonstrated the important influence of not only the gene involved, but also of PKD1 mutation type. Last, the analysis of clinical and genetic characteristics of 1341 patients from the Genkyst cohort allowed us to develop a prognostic algorithm, named the PROPKD score for predicting renal outcome in ADPKD. Our hope is that these works will participate in the development of individualized medicine in ADPKD, which is crucial in the context of the emerging targeted therapies.
248

Oxidative stress in breast and gynaecological carcinogenesis

Sova, H. (Henri) 25 March 2014 (has links)
Abstract Cancer is the leading cause of death worldwide. Despite the significant research effort, underlying mechanisms of carcinogenic processes are still poorly understood. In recent decades, a group of extremely reactive oxygen metabolites, reactive oxygen species (ROS), have been linked closely to carcinogenesis. Levels of ROS are constantly controlled by antioxidants to ensure stable redox balance in our cells. An aberrant cellular redox balance is thought to be connected to carcinogenesis by inflicting damage to cellular macromolecules and disturbing normal cellular signalling. In this work, the role of ROS in carcinogenesis was studied by observing the ROS-derived DNA damage marker 8-hydroxydeoxyguanosine (8-OHdG) in breast cancer and endometriosis-associated ovarian cancer. This marker was also measured in connection with endometriosis and PCOS to study the early stages of the carcinogenic process. In addition, peroxiredoxin antioxidant enzymes were studied in endometriosis-associated ovarian cancer to explore their impact on the carcinogenic process and relationship with ROS-derived DNA damage. There seems to be a decreasing trend in the expression of 8-OHdG in the development of breast cancer and endometriosis-associated ovarian cancer. In breast cancer, low levels of 8-OHdG in serum and in tumour tissue were found to be associated with more aggressive disease. In endometriosis-associated ovarian cancer, 8-OHdG and Prx II expressions in tissue decreased with malignant transformation from benign endometriosis tissue to ovarian cancer. Patients with PCOS were found to have lower levels of 8-OHdG in serum compared with healthy controls and metformin treatment further decreased 8-OHdG levels in obese patients. These results, together with observations is previous studies indicate that in breast cancer and endometriosis-associated ovarian cancer, a high level of ROS-derived DNA damage could be significant factor in the initiation stage of carcinogenesis, whereas in later stages carcinomas benefit from lower ROS levels that support tumour growth and survival via cellular signalling. In endometriosis, there seem to be high amounts of ROS-derived DNA damage, which could explain the increased ovarian cancer risk, while in PCOS, aberrant ROS levels could contribute to the pathogenesis of the disease itself and also to possible cancer incidence by inducing abnormal cellular signalling. / Tiivistelmä Syöpä on nykyisin maailman yleisin kuolinsyy. Vaikka syöpätutkimukseen kohdistetaan maailmanlaajuisesti huomattavia resursseja, syövän kehittymisen perimmäinen syy on edelleen heikosti tunnettu. Yhä kasvavan todistusaineiston perusteella happiradikaalien epäillään liittyvän läheisesti syövän kehittymiseen. Nämä erittäin reaktiiviset hapen aineenvaihduntatuotteet ovat välttämättömiä solujemme normaalille toiminnalle, mutta liian suurina määrinä ne voivat vaurioittaa solun rakenteita ja häiritä solun normaalia viestintää. Solut sisältävät useita antioksidantteja, joiden tärkeimpänä tehtävänä on kontrolloida happiradikaalien määrää ja näin ylläpitää solun hapetus-pelkistys -tasapaino. Tässä väitöskirjatutkimuksessa tutkittiin happiradikaalien yhteyttä syövän kehittymiseen tarkastelemalla niiden aiheuttaman DNA-vaurion merkkiainetta, 8-hydroksideoksiguanosiinia (8-OHdG), rintasyövässä ja endometrioosiin liittyvässä munasarjasyövässä sekä peroksiredoksiiniperheen antioksidanttientsyymejä endometrioosiin liittyvässä munasarjasyövässä. 8-OHdG:n avulla selvitettiin myös munasarjojen monirakkulaoireyhtymän (PCOS) ja endometrioosin yhteyttä syövän kehittymiseen. Lisäksi tutkittiin metformiinin vaikutusta happiradikaalien aiheuttamaan DNA-vaurioon. Väitöskirjatutkimuksen tulosten perusteella 8-OHdG:n määrä vähentyy rintasyövän edetessä ja endometrioosiin liittyvän munasarjasyövän kehittyessä. Matalat 8-OHdG -tasot syöpäkudoksessa ja verinäytteissä ovat yhteydessä aggressiivisempaan taudinkuvaan rintasyövässä. Endometrioosiin liittyvässä munasarjasyövässä kudoksen ilmentämä 8-OHdG ja Prx II vähentyi asteittain siirryttäessä hyvänlaatuisesta endometrioosista munasarjasyöpään. Munasarjojen monirakkulaoireyhtymässä potilaiden verinäytteiden 8-OHdG -tasot olivat merkittävästi matalammat terveisiin verrokkeihin verrattuna. Korkeilla happiradikaalipitoisuuksilla ja niistä aiheutuvalla DNA-vauriolla on väitöskirjatutkimuksen tulosten perusteella tärkeä rooli syövän syntyvaiheessa, kun taas syövän myöhemmissä kehitysvaiheissa matalat happiradikaalipitoisuudet tukevat syövän kasvua ja selviytymistä soluviestinnän avulla. Endometrioosipotilaiden kohonnut munasarjasyöpäriski vaikuttaisi olevan seurausta runsaasta happiradikaalien aiheuttamasta DNA-vauriosta endometrioosikudoksessa. Munasarjojen monirakkulaoireyhtymässä poikkeavien happiradikaalitasojen aiheuttama puutteellinen soluviestintä liittyy mahdollisesti taudin patogeneesiin ja syöpäriskiin.
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Autonomie des femmes atteintes du syndrome des ovaires polykystiques : entre gestion de la maladie et approche restaurative de la santé

Doudenkova, Victoria 12 1900 (has links)
Le syndrome des ovaires polykystiques (SOPK) est le désordre endocrinien le plus répandu chez la femme en âge de procréer. Ayant un impact significatif sur la qualité de vie, il est l’une des causes majeures d’infertilité et est associé à des conditions chroniques sérieuses comme le diabète de type 2, des cancers hormono-dépendants, et les maladies cardiovasculaires. Bien qu’il soit prévalent et ait des conséquences importantes, l’expérience des soins vécue par les femmes traduit des dimensions problématiques : manque de sensibilisation et d’information, délais de diagnostic, insensibilité, inattention et banalisation. Selon certaines recherches, les femmes ne sont pas satisfaites des traitements habituellement prescrits, comme la pilule contraceptive. Elles considèrent manquer d’options de traitement et seraient intéressées par d’autres modalités de soin. D’autres travaux mettent également l’accent sur l’importance du mode de vie (ex. nutrition et gestion du stress) qui peut améliorer le profil métabolique et endocrinien, ainsi que se répercuter de manière favorable sur la fonction reproductive. Le manque général d'attention à cette condition représente dès lors une étude de cas intéressante, reflétant des injustices systémiques en médecine. L’objectif de cette thèse est d’examiner les enjeux en lien avec l’autonomie des femmes affectées par le SOPK dans le cadre des soins de santé et de fertilité, et de proposer des pistes de solution visant à favoriser son expression. Ces enjeux sont analysés dans le contexte de la maladie chronique, où l’accent est surtout mis sur le traitement visant à soulager l'infertilité, mais qui néglige les approches restauratives en regard de la santé, notamment par des changements de mode de vie. L’analyse des enjeux est faite selon une approche relationnelle de l’autonomie en considérant deux modes d’expression : épisodique et programmatique. La mise en évidence de ces enjeux rend possible une réflexion sur ce que pourrait apporter une vision globale dans le soin du SOPK, s’articulant tout autant autour de la gestion de la maladie que d’une approche restaurative de la santé. Afin d’analyser les enjeux éthiques particuliers que pose le soin du SOPK, cette thèse utilise une perspective à la fois conceptuelle-normative et empirique. Ces deux perspectives permettent 6 de mieux comprendre les lacunes de l'approche médicale actuelle et de formuler des recommandations éclairées sur les meilleures façons d’y faire face. Par la reconnaissance de la nécessité d’une approche du soin intégrant tant les aspects relatifs à la prévention et à la gestion du SOPK qu’une visée restaurative à l’égard de la santé, cette thèse amène des retombées importantes pour les professionnels de la santé et les femmes affectées par le SOPK. Ce faisant elle présente des pistes permettant de soutenir tant l’autonomie épisodique que programmatique, ainsi que l’empowerment de ces femmes. / Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of childbearing age. It has a significant impact on quality of life and is one of the major causes of infertility. It is also associated with serious chronic conditions such as type 2 diabetes, hormonedependent cancers, and cardiovascular disease. While it is prevalent and has serious consequences, women's experience of care reflects problematic dimensions: lack of awareness and information, delays in diagnosis, insensitivity, inattention, and trivialization. Research shows that women are dissatisfied with commonly prescribed treatments such as the contraceptive pill. They report lacking treatment options and would be interested in other modalities of care. Research on PCOS also emphasizes the importance of lifestyle (e.g. nutrition and stress management) that can improve the metabolic and endocrine profile and have a positive impact on reproductive function. The general lack of attention to this condition is thus an interesting case study, reflecting systemic injustices in medicine. The objective of this thesis is to examine issues related to the autonomy of women affected by PCOS in the context of health care and fertility, and to propose ways to promote the expression of autonomy. The thesis analyzes these issues in the context of chronic disease, whereby treatment focuses on alleviating infertility and neglects restorative approaches to health, particularly through effective lifestyle changes. The analysis is based on the conceptual framework of relational autonomy, and considers two possible modes of autonomy expression: episodic and programmatic. Awareness of these issues makes it possible to reflect on what a holistic approach could bring to PCOS care, considering both disease management and a restorative approach to health. To consider the ethical challenges related to the care of PCOS, this thesis employs both a conceptual-normative and an empirical perspective. Both allow a better understanding of the shortcomings of the current medical approach and an informed recommendation for better ways of responding to these challenges. By recognizing the need for prevention and management of PCOS, as well as a restorative approach to health, this thesis has substantial implications for healthcare professionals and women, suggesting ways of supporting both episodic and programmatic autonomy and empowerment of affected women.
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Kvinnors upplevelser av att leva med polycystiskt ovarialsyndrom : En litteraturstudie / Women’s experiences of living with polycystic ovary syndrome : A literature review

Abduljabar, Fada, Fayete, Marthe January 2022 (has links)
Abstrakt Bakgrund: Polycystiskt ovarialsyndrom är en endokrin sjukdom som drabbar 5-10% av kvinnor i fertil ålder. Orsaken till diagnosen är ännu inte fastställd men kan ha en viss anknytning till ärftlighet. I samband med diagnosen förekommer ett flertal symtom som medför lidande. Syftet: Var att beskriva kvinnors upplevelser av att leva med Polycystiskt ovarialsyndrom. Metod: Fjorton vetenskapliga studier analyserades med en kvalitativ innehållsanalys med manifest induktiv ansats. Resultat: Fem slutliga kategorier framkom i resultatet: Att leva med bristande förmåga att bli gravid, Att känna skam och dölja sitt utseende, Att påverkas av diagnosen inifrån och utifrån, Att leva med en diagnos som förändrar relationer och Att känna sig missnöjd i mötet med sjukvårdspersonal. Slutsats: Att leva med kronisk sjukdom innebär förändringar i vardagen. En djupare förståelse av kvinnors upplevelser av PCOS kan bidra till förbättrad omvårdnad utifrån ett helhetsperspektiv.

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