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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.
71

Primary Care Visits by the Postpartum Women with Gestational Diabetes and Hypertension: Analysis of Medicaid Claims Data in South Carolina

Dahal, Kajol, White, Melissa, Hale, Nathan 25 April 2023 (has links)
Introduction: Gestational diabetes (GDM) affects one in three pregnancies and women with GDM have a 10-fold higher risk of developing type-2 diabetes during their lifetime. Similarly, hypertensive disorders (HPD) of pregnancy affect up to one in seven pregnancies and have a 4-fold increase in the risk of hypertension and a 2-fold risk of cardiovascular diseases (CVD) over the lifetime. Primary care (PC) transitions are critical for the management of GDM and HDP to reduce the long-term risk of developing type-2 diabetes, hypertension, and CVD. Despite clinical guidelines recommending PC follow-up for continuous and sustainable care practice, only 50% of postpartum mothers transition to PC within 12 months. Few studies examine this issue and none in South Carolina. Therefore, our study uses Medicaid Claims data to examine the extent to which postpartum mothers with GDM and HDP transition to PC within 12 months of childbirth. Methods: We examined cross-sectional data of Medicaid women with a live birth in the years 2017 and 2018 in South Carolina. Women above the age of 20, receiving postpartum services within 12 months of delivery were included in the study. Primary care visits was the outcome variable of interest. Any women with at least one primary care visit (Family/General Practice Physician visit) claim in the 12 months following birth were considered as a primary care transition. GDM, HDP, and both (GDM &HDP) were the primary independent variables of interest. Results: In 14,273 postpartum mothers, the prevalence of GDM, HDP, and both (GDM & HDP) were found to be 10.02%, 15.05%, and 3.60% respectively. Among the women with GDM, 47.02% had visited PC compared to 35.02% of women without GDM (p<0.001). Similarly, 48.12% of women with HDP visited PC compared to 34.23% of women without HDP (p<0.001). In addition, 52.66% of women with both (GDM & HDP) visited PC compared to 35.72% of women without both (GDM & HDP) (p<0.001). After adjusting for maternal age, ethnicity, residence, and pay category, women with GDM were 1.43 times more likely to visit PC as compared to the women with no GDM (95% CI: 1.27–1.61). Similarly, the odds of visiting PC by women with HDP was 1.67 times higher as compared to women without HDP (95% CI: 1.51 – 1.84). Conclusion: In this study, postpartum mothers with GDM and HDP had higher odds of PC visits compared with those without GDM and without HDP respectively. This is positive. However, the overall percentage of women visiting PC with chronic disease was lower than 50%. To change health outcomes among women with chronic diseases like GDM and HDP, lifelong screening and disease management are needed. It is necessary to link postpartum mothers with PC to improve illness management and raise screening adherence. However, more barriers preventing under-resourced women from receiving PC should be analyzed and addressed.
72

Peer Support Education for uncontrolled hypertension among African Americans adults

Semper, Melvina Juliana 01 January 2015 (has links)
Hypertension is a major chronic health problem that can lead to heart attack, stroke, and kidney failure. African Americans disproportionately suffer from the morbidity and mortality of hypertension-related illnesses. The purpose of this comparative project was to determine the impact of peer support educational workshops as an avenue for lifestyle modification, using changes in blood pressure (BP) before and after participation. The target population consisted of 64 African Americans with hypertension in Brooklyn NY, aged 20 to 65 years old. BP measurements were taken within 1 month before and after participating in a weekly peer support educational workshop facilitated by designated healthcare providers. The health belief model, using the tenets of lifestyle modification, societal support and health education, was used to guide the study. Demographic data were collated and categorized, considering numeric values used to represent age, income level, and education. Normality testing of the study variables was performed to ensure that the data followed a normal distribution. The study variables included the pre- and post-test systolic and diastolic BP. A t test was used in order to compare the 2 groups, revealing a statistically lower significant score from African Americans who participated than those who did not. African Americans who adhered to peer support educational regimens in the workshops revealed a statistically significant lower diastolic BP than those who did not participate. This research contributes to social change by providing evidence-based recommendations that government and health care professionals may use to create strategic plans to promote the well-being of individuals and communities.
73

Die Rolle der Bone Morphogenetic Proteins (BMP)-5 und -7 in der humanen Normalniere und bei der hypertensiven Nephropathie / The role of Bone Morphogenetic Proteins (BMP)-5 and -7 in adult human kidney and hypertensive nephrosclerosis

Tampe, Björn 30 May 2012 (has links)
No description available.
74

Untersuchung zum Einfluss von Bluthochdruck auf die Immunreaktion nach experimentellem Schlaganfall

Möller, Karoline 14 December 2021 (has links)
Einleitung: Ischämische Schlaganfälle ziehen ausgeprägte Entzündungsprozesse im Gehirn sowie Immunreaktionen in der Körperperipherie nach sich, welche den Erkrankungsverlauf und die Regeneration maßgeblich beeinflussen. Die Modulation dieser Immunantwort stellt folglich einen vielversprechenden experimentellen Ansatz in der Schlaganfalltherapie dar. Der ischämische Schlaganfall ist außerdem mit verschiedenen Komorbiditäten und Risikofaktoren assoziiert, deren Auswirkungen auf die komplexen postischämischen pathophysiologischen Prozesse nur in Teilen aufgeklärt sind. So hat eine arterielle Hypertonie (Bluthochdruck) als wichtigster modifizierbarer Risikofaktor durch die Induktion von Gefäßschäden eine zentrale Bedeutung für die Pathogenese von ischämischen Schlaganfällen und geht außerdem mit einer Aktivierung des Immunsystems einher. Der konkrete Einfluss der Hypertonie auf die postischämische Entzündungsreaktion wurde bislang nicht hinreichend untersucht. Die Einbeziehung wichtiger Begleiterkrankungen, wie Bluthochdruck, in die präklinische Schlaganfallforschung gewinnt zunehmend an Bedeutung, da ein erweitertes Verständnis der pathophysiologischen Zusammenhänge auch eine bessere Übertragbarkeit neuer immunmodulatorischer Therapiekonzepte auf den Menschen in Aussicht stellt. Zielstellung: Das Hauptziel dieser Arbeit ist die Identifizierung pathofunktioneller Zusammenhänge zwischen der Immunantwort nach Schlaganfall und manifestem Bluthochdruck. Dafür wurde die zentrale und periphere Entzündungsreaktion nach experimentellem Schlaganfall in einem prämorbiden hypertensiven Tiermodell (spontan-hypertensive Ratte, SHR) im Vergleich mit normotensiven Tieren mithilfe von vorwiegend durchflusszytometrischen, histologischen und molekularbiologischen Methoden analysiert. Daneben sollte das verwendete hypertensive Tiermodell für die Untersuchung immunologischer Aspekte der translationalen Schlaganfallforschung evaluiert werden. Tiere, Material und Methoden: Für alle Tierversuche und Organentnahmen wurden ausschließlich männliche Ratten der Stämme Wistar-Kyoto und SHR im Alter von 12 bis 14 Wochen verwendet. Die Induktion des ischämischen Infarkts erfolgte mithilfe eines permanenten, transkraniellen Schlaganfallmodells oder mittels photochemischer Thrombose. In Abhängigkeit von der Untersuchungsgruppe wurden die Tiere 1 oder 4 Tage nach Infarktinduktion bzw. Sham-Operation schmerzfrei getötet. Neben wenigen neuroanatomischen und neurofunktionellen Ausleseparametern wurde als Hauptzielgröße die Immunzellverteilung im Gehirn und im Blut erfasst. Dafür wurden Hirnzellisolate und Vollblutproben mit maximal 8 fluoreszenzgekoppelten Antikörpern in verschiedenen Kombinationen markiert und in einem 3-Laser-Durchflusszytometer (FACSCanto II) gemessen und ausgewertet. Zudem wurden in kryokonservierten Hirnschnitten relevante Immunzellpopulationen und Adhäsionsmoleküle mittels Immunfluorezenztechniken markiert und für die Darstellung der räumlichen Verteilung mit einem Konfokal-Mikroskop (LSM710, Zeiss) analysiert. Zusätzlich wurde die Gen-und Proteinexpression selektiver Zytokine und Adhäsionsmoleküle in dissoziiertem Hirngewebe ermittelt. Die statistische Auswertung wurde je nach erfasster Zielgröße mittels zweiseitigem t-Test, Wilcoxon Rangsummentest, Pearson-Korrelation oder Varianzanalyse-Verfahren durchgeführt. Ein Signifikanzniveau von p<0,05 wurde für alle statistischen Verfahren festgelegt. Ergebnisse: Neben einer vergrößerten Läsion konnte in hypertensiven Tieren insbesondere eine gesteigerte Infiltration von Zellen des angeborenen Immunsystems in das ischämische Hirn gezeigt werden. Eine Verschiebung des Makrophagen-Granulozyten-Verhältnisses wies darüber hinaus auf eine veränderte Entzündungskinetik bei Vorliegen von Bluthochdruck hin. Weiterhin wurde in Tieren mit arterieller Hypertonie eine erhöhte Zahl von zirkulierenden Monozyten und Granulozyten beobachtet. Im Hirngewebe von spontan-hypertensiven Ratten nach Schlaganfall wurden außerdem eine verminderte Expression des antiinflammatorisch wirksamen Zytokins Interleukin 10, erhöhte Expressionsraten selektiver Leukozyten-rekrutierender Chemokine sowie eine vermehrte Expression des Adhäsionsmoleküls ICAM-1 auf infiltrierenden Leukozyten erfasst. Daneben konnten modellabhängige Einflüsse der verschiedenen Induktionsmethoden auf die Immunreaktion identifiziert werden. Schlussfolgerung: Die Ergebnisse weisen deutlich auf einen Zusammenhang zwischen einem bestehenden arteriellen Hypertonus und einer gesteigerten entzündlichen Reaktion im Gehirn nach experimentellem Schlaganfall hin und zeigen mögliche zugrundeliegende Mechanismen auf. Gleichzeitig unterstreicht die Arbeit durch eine differenzierte Analyse methodischer und modellabhängiger Einflüsse die Unerlässlichkeit, präklinische Ergebnisse kritisch zu hinterfragen und in unterschiedlichen Modellen zu überprüfen. Auf Grundlage der Untersuchungen kann die spontan-hypertensive Ratte zudem als ein für die translationale Schlaganfallforschung geeignetes prämorbides Tiermodell beurteilt werden, in welchem sich der Einfluss des Risikofaktors Bluthochdruck auf die Entwicklung und den Verlauf der postischämischen Entzündung gut abbilden lässt.:Inhaltsverzeichnis Abkürzungsverzeichnis 1 Einleitung 2 Literaturübersicht 2.1 Humaner Schlaganfall - Grundlagen 2.1.1 Epidemiologie und sozioökonomische Bedeutung 2.1.2 Allgemeine Definition und Ätiologie 2.2 Postischämische Entzündung und systemische Immunantwort 2.2.1 Allgemein 2.2.2 Initialer Pathomechanismus der sterilen Entzündung im Gehirn 2.2.3 Immunzellen in der postischämischen Entzündung 2.2.4 Periphere Immunmodulation und postischämische Immunsuppression 2.2.5 Auflösung der Entzündungsreaktion 2.3 Schlaganfall und Hypertonie 2.4 Translation - Schlaganfall im Tiermodell 2.4.1 Tiermodelle 2.4.2 Methoden zur Induktion des experimentellen Schlaganfalls 2.4.3 Translationsproblematik 2.4.4 Die spontan-hypertensive Ratte als prämorbides Tiermodell 2.5 Therapieverfahren und therapeutische Ansätze 3 Zielstellung und Aufbau der Arbeit 4 Publikation 1 5 Publikation 2 6 Zusammenfassende Diskussion 6.1 Infarktvolumina und funktionelle Daten 6.2 Immunzytologie im Hirngewebe 6.3 Immunzytologie im peripheren Blut 6.4 Leukozytenrekrutierung ins ischämische Gewebe 6.5 Fazit, Limitationen und Ausblick 7 Zusammenfassung 8 Summary 9 Literaturverzeichnis Danksagung / Introduction: Ischemic strokes lead to a sequence of immune responses, including pronounced tissue inflammation in the brain as well as distinct reactions of the peripheral immune system that consistently influence disease process and outcome. The modulation of these immune responses therefore represents a promising experimental approach in stroke therapy. Ischemic stroke is also associated with various comorbidities and risk factors whose effects on the complex postischemic pathology have only been partially elucidated. Being the most important modifiable risk factor this especially applies to arterial hypertension that has a central role in the pathogenesis of ischemic stroke by inducing vascular damage but is also associated with a strong activation of the immune system. However, the specific influence of hypertension on postischemic inflammation has not been sufficiently investigated. Besides, the integration of hypertension and other important concomitant diseases is becoming a more regular tool in preclinical stroke modelling in order to expand the understanding of pathophysiological interactions and overcome the translational gap of new immunomodulatory therapies. Aim: The main objective of this work is the identification of pathofunctional interations between the immune response after stroke and preexisting arterial hypertension. For this purpose, the central and peripheral inflammatory response after experimental stroke was investigated in a premorbid hypertensive animal model (spontaneously hypertensive rat, SHR) in comparison with normotensive animals by means of flow cytometric, histological and molecular biological methods. In addition, the hypertensive animal model was supposed to be assessed regarding its suitability for the investigation of immunological aspects in translational stroke research. Material and Methods: For all animal experiments and organ removal, only male rats of the Wistar Kyoto and SHR strains aged 12 to 14 weeks were used. Induction of experimental stroke was performed using either a permanent transcranial stroke model or photochemical thrombosis model. Depending on the study group, animals were killed painlessly 1 or 4 days after infarct induction or sham surgery respectively. In addition to few neuroanatomic and neurofunctional readout parameters, immune cell distribution in the brain and blood was captured as primary variable. Therefore, brain cell isolates and whole blood samples labeled with a maximum of 8 fluorescence-coupled antibodies in different combinations were measured and analyzed in a 3-laser flow cytometer (FACSCanto II). Furthermore, immunofluorescence techniques were applied on cryopreserved brain sections in order to image spatial distribution of relevant immune cell populations and adhesion molecules by means of confocal microscopy (LSM710, Zeiss). In addition, the mRNA and protein expression of selective cytokines and adhesion molecules was determined in dissociated brain tissue. Depending on the targeted parameter statistical analyses were performed by using two-sample t-test, Wilcoxon rank-sum test, Pearson correlation coefficient or analysis of variance. A significance level of p<0.05 was set for all statistical methods. Results: In addition to an enlarged lesion, in hypertensive animals an increased infiltration of cells of the innate immune system to the ischemic brain area was detected. A shift of the macrophage-granulocyte-ratio further indicated an altered inflammatory profile in hypertensive rats. Furthermore, an increased number of circulating monocytes and granulocytes were observed in animals with hypertension. In brain tissue of SHR after stroke, a decreased expression of the anti-inflammatory cytokine interleukin 10 were recorded along with increased expression levels of selective leukocyte-recruiting chemokines and an increased expression of the adhesion molecule ICAM-1 on infiltrating leukocytes. In addition, caused by different induction methods, model-dependent impact on the immune reaction could be identified. Conclusion: The results clearly indicate a relationship between existing arterial hypertension and an increased inflammatory response in the brain after experimental stroke and point out potential underlying mechanisms. At the same time, by adopting a differentiated view of methodological and model-dependent influences, the work underscores the need for critical reflection and constant verification of preclinical results in different models. Finally the work validates the SHR strain as a suitable premorbid preclinical system for further translational research since it well models the influence of hypertension on the development and course of postischemic inflammation.:Inhaltsverzeichnis Abkürzungsverzeichnis 1 Einleitung 2 Literaturübersicht 2.1 Humaner Schlaganfall - Grundlagen 2.1.1 Epidemiologie und sozioökonomische Bedeutung 2.1.2 Allgemeine Definition und Ätiologie 2.2 Postischämische Entzündung und systemische Immunantwort 2.2.1 Allgemein 2.2.2 Initialer Pathomechanismus der sterilen Entzündung im Gehirn 2.2.3 Immunzellen in der postischämischen Entzündung 2.2.4 Periphere Immunmodulation und postischämische Immunsuppression 2.2.5 Auflösung der Entzündungsreaktion 2.3 Schlaganfall und Hypertonie 2.4 Translation - Schlaganfall im Tiermodell 2.4.1 Tiermodelle 2.4.2 Methoden zur Induktion des experimentellen Schlaganfalls 2.4.3 Translationsproblematik 2.4.4 Die spontan-hypertensive Ratte als prämorbides Tiermodell 2.5 Therapieverfahren und therapeutische Ansätze 3 Zielstellung und Aufbau der Arbeit 4 Publikation 1 5 Publikation 2 6 Zusammenfassende Diskussion 6.1 Infarktvolumina und funktionelle Daten 6.2 Immunzytologie im Hirngewebe 6.3 Immunzytologie im peripheren Blut 6.4 Leukozytenrekrutierung ins ischämische Gewebe 6.5 Fazit, Limitationen und Ausblick 7 Zusammenfassung 8 Summary 9 Literaturverzeichnis Danksagung
75

Genetic and epidemiological aspects of implantation defects : Studies on recurrent miscarriage, preeclampsia and oocyte donation

Elenis, Evangelia January 2016 (has links)
Implantation requires complex molecular and cellular events involving coagulation, angiogenesis and immunological processes that need to be well regulated for a pregnancy to establish and progress normally.  The overall aim of this thesis was to study different models associated with atypical angiogenesis, impaired implantation and/or placentation, such as recurrent miscarriage (RM), oocyte donation (OD) and preeclampsia. Histidine-rich glycoprotein (HRG), a serum protein with angiogenic potential has been previously shown to have an impact on implantation and fertility.  In two retrospective case-control studies, women suffering from RM (Study I) and gestational hypertensive disorders (GHD) (Study IV) have been compared to healthy control women, regarding carriership of HRG genotypes (HRG A1042G and C633T SNP, respectively).  According to the findings of this thesis, heterozygous carriers of the HRG A1042G SNP suffer from RM more seldom than homozygous carriers (Study I).  Additionally, the presence of the HRG 633T allele was associated with increased odds of GHD (GHD IV).  Studies II and III comprised a national cohort of relatively young women with optimal health status conceiving singletons with donated oocytes versus autologous oocytes (spontaneously or via IVF).  We explored differences in various obstetric (Study II) and neonatal (Study III) outcomes from the Swedish Medical Birth Register.  Women conceiving with donated oocytes had a higher risk of GHD, induction of labor and cesarean section, as well as postpartum hemorrhage and retained placenta, when compared to autologously conceiving women.  OD infants had higher odds of prematurity and lower birthweight and length when born preterm, compared to neonates from autologous oocytes.  With regard to the indication of OD treatment, higher intervention but neverthelss favourable neonatal outcomes were observed in women with diminished ovarian reserve; the risk of GHD did not differ among OD recipients after adjustment. In conclusion, HRG genetic variation appears to contribute to placental dysfunction disorders.  HRG is potential biomarker that may contribute in the prediction of the individual susceptibility for RM and GHD.  Regarding OD in Sweden, the recipients-despite being of optimal age and health status- need careful preconceptional counselling and closer prenatal monitoring, mainly due to increased prevalence of hypertensive disorders and prematurity.
76

Buněčná signalizace v myokardu spontánně hypertenzích potkanů s transgenní a kongenní expresi CD36 / Myocardial cell signaling in spontaneously hypertensive rats with transgenic and congenic expression of CD36

Klevstigová, Martina January 2013 (has links)
Long-chain fatty acids (LCFA) are the primary energy source in the myocardium and an imbalance in the LCFA and glucose utilization could cause cardiovascular diseases. More than 50% of LCFA uptake by the heart is mediated by the fatty acid translocase CD36 and disruption of its function has been shown to impair cardiovascular functions. The spontaneously hypertensive rat (SHR) harbors a deletion variant of the Cd36 gene that results in reduced LCFA transport into myocytes. Therefore, the main aim of this thesis was to investigate the importance of a functional CD36 to sustain normal physiological functions of the heart. We used SHR and two genetic modified SHR strains, the congenic SHR-4 and the transgenic SHR-Cd36, with fully functional CD36. They differ in the CD36 expression and in the manner how they were derived from the SHR. CD36 has been proven to play a role in the pathogenesis of insulin resistance. Therefore we analyzed the effect of a functional CD36 on insulin resistance and protein kinase C (PKC) expression, which is known to be involved in the mechanism of insulin resistance, in the heart of SHR-4 and SHR. We showed that the SHR-4 had lower serum free fatty acids (FFA) and triacylglycerols (TAG) concentrations, indicating improved insulin sensitivity. Furthermore, SHR-4 had increased...
77

Timing, reward processing and choice behavior in four strains of rats with different levels of impulsivity.

Garcia Aguirre, Ana I. January 1900 (has links)
Master of Science / Department of Psychology / Kimberly Kirkpatrick / Several studies have examined timing and impulsive choice behavior in spontaneously hypertensive rats (SHR) as a possible pre-clinical model for Attention Deficit Hyperactivity Disorder (ADHD). However, the strain has not been specifically selected for the traits of ADHD and as a result their appropriateness as a model has been questioned. This study investigated whether SHR would exhibit timing deficits, poor reward processing and impulsive behavior in comparison to the Wistar Kyoto (WKY) control strain in a discrete-trial choice task. In addition, as a first approach to find another potential animal model of ADHD, we evaluated a strain that has shown high levels of impulsivity, the Lewis (LEW) rats and compared them with the Wistar (WIS) rats. In the first phase of the experiment, rats could chose a lever associated with a Smaller-sooner (SS) reward of 1 pellet delivered after 10 s and a Larger-later (LL) reward of 2 pellets delivered after 30 s. Subsequently, the rats were exposed to different phases, where the reward on the LL choice was increased to 3 and 4 pellets and where the delay to the SS choice was increased to 15 and 20 s. The SHR and WKY strains did not differ in their timing or choice behavior. In comparison to WIS, LEW showed timing deficits in both manipulations and deficits in choice behavior in the delay manipulation, indicating deficits in time processing. Individual differences among the rat within a strain accounted a significant proportion of the total variance and contributed more variance than the strain of the rat. These results indicate that the SHR and LEW strains are not sufficiently homogeneous with respect to impulsive choice behavior to be considered as viable models for impulse control disorders such as ADHD.
78

Efeitos do treinamento físico aeróbio sobre as alterações vasculares estruturais, mecânicas e funcionais de ratos espontaneamente hipertensos: mecanismos implicados / Effects of aerobic exercise trining on the vascular structural mechanical and functional alterations of spontaneously hipertensive rats: mechanisms involved

Redondo, Fernanda Roberta Roque 28 July 2010 (has links)
A hipertensão arterial (HA) é um importante problema de saúde pública e representa um dos fatores de risco mais relevantes na etiologia das doenças cardiovasculares. O incremento na resistência vascular periférica (RVP) é a principal característica da HA e está diretamente associado a alterações vasculares estruturais, mecânicas e funcionais. O aumento do estresse oxidativo tem sido considerado um importante fator que contribui para o desenvolvimento e estabelecimento da HA. A prática regular de exercício físico aeróbio, utilizada como medida não farmacológica para o tratamento da HA, tem se mostrado efetiva em reduzir os valores de pressão arterial através da promoção de diversas adaptações cardiovasculares. Este estudo teve como objetivo avaliar os efeitos do treinamento físico (TF) aeróbio sobre as alterações vasculares de artérias coronárias e mesentéricas de resistência induzidas pela HA. Para isso ratos espontaneamente hipertensos (SHR) foram submetidos a um protocolo de TF aeróbio. Este TF promoveu alterações estruturais, avaliadas através de um miógrafo de pressão, como o remodelamento vascular em coronárias e redução de colágeno com aumento na área das fenestras da elastina em mesentéricas, as quais foram associadas com a melhora na rigidez vascular. Além disso, o TF induziu melhora da função endotelial, avaliada através de estudos de reatividade vascular, principalmente mediada por aumento na disponibilidade de óxido nítrico ocasionada por redução do estresse oxidativo. Os resultados sugerem que o TF promoveu alterações vasculares que podem contribuir para diminuir a RVP e reduzir a pressão arterial / Hypertension is a major public health problem and represents one of the most important risk factors in the etiology of cardiovascular diseases. Peripheral vascular resistance increased is the main feature of hypertension and it is directly associated with vascular structural, mechanical and functional alterations. Oxidative stress increased has been considered an important factor that contributes to the development and establishment of hypertension. Regular exercise training, used as a non pharmacological treatment of hypertension, has been effective reducing blood pressure by promoting several cardiovascular adaptations. The aim of the present study was evaluate the effects of treadmill training on the vascular alterations of coronary and mesenteric resistance arteries induced by hypertension. Then, spontaneously hypertensive rats (SHR) were submitted to an aerobic exercise training protocol. The exercise training promoted structural alterations, measured by a pressure myography, as coronary vascular remodeling and collagen reduction and also the area of fenestrae in the elastin of mesenteric arteries were increased, which were associated with vascular stiffness improvement. In addition, the exercise training improved the endothelial function in both arterial beds, as evaluated by vascular reactivity analysis, mediated primarily by increasing nitric oxide availability caused by oxidative stress reduction. The results suggest that exercise training promoted vascular changes that can contribute to reduce peripheral vascular resistance and blood pressure
79

Efeitos da hipertensão e do treinamento aeróbio sobre a expressão/atividade de diferentes componentes da barreira hematoencefálica. / Effects of hypertension and aerobic training on the expression / activity of different components of the blood-brain barrier.

Fragas, Matheus Garcia de 29 June 2018 (has links)
A hipertensão arterial cursa com disfunção autonômica e lesão da barreira hematoencefálica (BHE) em áreas de controle autonômico. Demonstramos recentemente que o treinamento aeróbio corrige a lesão da BHE, e a disfunção autonômica, a qual se encontra correlacionada com a integridade da BHE observada nos hipertensos treinados. O objetivo deste trabalho é avaliar a expressão gênica e proteica de componentes da BHE envolvidos na mediação das respostas cardiovasculares à hipertensão e ao treinamento aeróbio (T). Ratos espontaneamente hipertensos (SHR) e seus controles normotensos (WKY) (250-300g) foram submetidos ao protocolo de T em esteira ou mantido sedentários (S) por 4 semanas. Ao final do T os animais dos grupos experimentais foram canulados para aquisição das variáveis hemodinâmicas. A seguir procedeu-se à infusão intra-arterial de 2 corantes (Rodamina-d, 70 KD, e FITC-d,10 KD) e 20 min após os encéfalos foram coletados para realização de ensaios de fluorescência no Núcleo Paraventricular do Hipotálamo (PVN). Outros ratos dos grupos experimentais foram perfundidos com salina via transcardíaca e realizada a microdissecção do PVN. O mRNA foi extraído e sua concentração de foi analisada pela técnica de RT-PCR. Para investigar os efeitos da hipertensão e do T nos componentes da BHE, foram utilizados os seguintes primers: Occludina, Claudina-5, Zônula Ocludens 1 (proteínas da junção oclusiva), Caveolina-1 (indicador de transporte transcelular), Laminina alfa 1 e Colágeno 4 (componentes da membrana basal), PDGFR&beta; (marcador de pericitos)e Aquaporina-4 (indicador de podócitos de astrócitos), todos eles normalizados para o HPRT endógeno. Os dados de PCR em tempo real foram quantificados pelo método 2&Delta; &Delta;CT. Além disso, outros ratos dos mesmos grupos experimentais foram perfundidos com paraformaldeído 4% para a fixação do encéfalo. O tecido foi crioprotegido e seccionado em criostato, 30 um, os cortes foram incubados em anticorpos primários (Reca-1(marcador endotelial), Claudina-5, Caveolina-1, PDGFR&beta; e Aquaporina-4) e secundários (Alexa Flúor 488 e 594), e sua quantificação no PVN foi realizada através da densidade integrada. Não foi observada diferença na pressão arterial entre os grupos T e S, porém, houve bradicardia de repouso nos animais T (SHR-T:317±3 e WKY-T:308±2) comparados com os animais S (SHR-S: 344±4 e WKY-S: 323±3). A permeabilidade da BHE foi reduzida e normalizada pelo T nos animais hipertensos (SHR-S: 13,6±1,2% e SHR-T: 3,8±0,4%; WKY-S: 3,9±0,2% e WKY-T: 4,1±0,16%), e análise do RT-PCR não mostrou nenhuma diferença para Claudina, PDGFR&beta; e Aquaporina-4 entre os T e S. A expressão gênica de Caveolina-1 estava aumentada nos SHR comparado aos WKY, e o T foi capaz de reduzir sua expressão (SHR-T: 1,05±0,1). O que foi confirmado pela expressão proteica no PVN: a Caveolina-1 encontrava-se aumentada significativamente nos SHR-S em relação aos WKY, e o T reduziu sua expressão no PVN dos SHR. Conclusão: Nossos dados sugerem que o aumento da permeabilidade da BHE no PVN de hipertensos é devida ao aumento de transcitose, identificada pela expressão de Caveolina-1 e que o treinamento aeróbio reverte esta permeabilidade ao reduzir o transporte transcelular sem alterar o transporte paracelular. / The arterial hypertension courses with autonomic dysfunction and Blood Brain Barrier (BBB) damage in areas of autonomic control. We recently demonstrated that aerobic training corrects the damage to the BBB, and autonomic dysfunction, which is correlated with the integrity of the BBB observed in trained hypertense subjects. The objective of this work is to evaluate the gene and protein expression of BBB components involved in mediating cardiovascular responses to hypertension and aerobic training (T). Spontaneously hypertensive rats (SHR) and their normotensive controls (WKY) (250-300g) were submitted to treadmill protocol or maintained sedentary (S) for 4 weeks. At the end of the T, the animals of the experimental groups were cannulated to acquire the hemodynamic variables. Intra-arterial infusion of two dyes (Rhodamine-d, 70 KD, and FITC-d, 10 KD) and 20 min after brains were collected for fluorescence assays in the Paraventricular Nucleus of hypothalamus (PVN). Other rats from the experimental groups were perfused with transcardiacally with saline and the PVN was microdissected. The mRNA was extracted and its concentration was analyzed by the RT-PCR technique. To investigate the effects of hypertension and T in the BBB components, the following primers were used: Occludin, Claudin-5, Zonula Ocludens 1 (tight junction proteins), Caveolina-1 (indicator of transcellular transport), Laminin &alpha; 1 and Collagen-4 (basement membrane components), PDGFR&beta; (pericyte marker) and Aquaporin-4 (astrocyte podocyte indicator), all standardized for endogenous HPRT. Real-time PCR data were quantified by the method 2&Delta;&Delta;CT. In addition, other rats from the same experimental groups were perfused with 4% paraformaldehyde for fixation of the brain. The tissue was cryoprotected and cross-sectioned, 30 m, sections were incubated on primary (Reca-1 (endothelial marker), Claudin-5, Caveolin-1, PDGFR&beta; and Aquaporin-4) and secondary antibodies (Alexa Fluor 488 and 594), and its quantification in thePVN was performed through the integrated density. There was no difference in blood pressure between the T and S groups, but there was resting bradycardia in the T animals (SHR-T: 317 ± 3 and WKY-T: 308 ± 2) compared to S controls (SHR-S: 344 ± 4 and WKY-S: 323 ± 3). The permeability of BBB was reduced and normalized by T in hypertensive animals (SHR-S: 13.6 ± 1.2% and SHR-T: 3.8 ± 0.4%; WKY-S: 3.9 ± 0, 2% and WKY-T: 4.1 ± 0.16%), and RT-PCR analysis showed no difference for Claudin-5, PDGFR&beta; and Aquaporin-4 between T and S. Caveolin-1 gene expression was increased in SHR compared to WKY, and T was able to reduce its expression (SHR-T: 1.05 ± 0.1). This was confirmed by protein expression in PVN: Caveolin-1 was significantly increased in SHR-S relative to WKY, and T reduced its expression in the PVN of SHR. Conclusion: Our data suggest that increased permeability of BBB in the PVN of hypertense individuals is due to the increase transcytosis as identified by Caveolin-1 expression and that aerobic training reverses this permeability by reducing transcellular transport without altering the paracellular transport.
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Ocorrência familial e associação de polimorfismos dos genes H19 e IGF2 com as Síndromes Hipertensivas Gestacionais / Familial Occurrence and H19 and IGF2 Polymorphism Association with Gestational Hypertensive Disorders

Araujo, Francielle Marques 05 March 2007 (has links)
ARAUJO, F. M. Ocorrência Familial e Associação de Polimorfismos dos Genes H19 e IGF2 com as Síndromes Hipertensivas Gestacionais. 2007. 118f. Disertação (Mestrado) Faculdade de Medicina, Universidade de São Paulo, Ribeirão Preto, 2007. As síndromes hipertensivas gestacionais [Pré-eclâmpsia/eclâmpsia (PE/E), hipertensão gestacional (HG) e hipertensão arterial crônica (HAC)] estão entre as maiores causas de morte materna e fetal. A PE é a mais prevalente dessas síndromes e o papel dos fatores genéticos na sua etiologia é bem aceito, embora o padrão de herança seja ainda assunto para debate. Os genes H19 e IGF2 sofrem imprinting (marcação) genômico e estão envolvidos na formação placentária e no desenvolvimento fetal. O objetivo do presente trabalho foi a pesquisa de ocorrência familial e da associação com os polimorfismos H19/RsaI e do IGF2/ApaI das síndromes hipertensivas gestacionais e do peso do recém-nascido. Todas as pacientes do estudo foram atendidas no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo e o projeto foi aprovado pelo Comitê de Ética deste hospital e pela Comissão Nacional de Ética em Pesquisa. Para a condução do estudo familial foram selecionadas 226 mulheres (75 apresentavam PE, 49 com HG e 102 do grupo controle). Os dados foram analisados pelos Testes Exato de Fisher e do Qui-quadrado, resultando em uma maior freqüência estatisticamente significativa (p <0,05) de parentes de primeiro-grau com PE/E entre o grupo de PE/E comparado aos outros grupos. Não foi observada influência da cor da pele na distribuição entre os grupos de pacientes. Para a pesquisa de polimorfismos de comprimento de fragmento de restrição H19/RsaI (alelos A e B) e IGF2/ApaI (alelos A e G) através da reação em cadeia da polimerase , foi extraído DNA de sangue periférico de 236 pacientes (55 apresentavam PE, 40 com HG, 34 com HAC e 107 do grupo controle). Os resultados, analisados através dos Testes do Qui-quadrado e G, não mostraram associação estatisticamente significativa entre os polimorfismos e as síndromes hipertensivas gestacionais ou HAC. Houve uma maior freqüência do alelo G na população estudada. Foi observado que em torno de 80% das pacientes dos quatro grupos estudados apresentou pelo menos uma cópia do alelo B e uma do alelo G, concomitantemente. A associação do peso do recém-nascido com os polimorfismos foi analisada utilizando-se os Testes Kolmogorov-Smirnov (a P<0,05) e os Não-paramétricos de Kruskal-Wallis (a P<0,05), não tendo sido evidenciadas diferenças estatisticamente significativas. No grupo da PE houve uma diminuição estatisticamente significativa do peso dos recém-nascidos quando não havia correção para a idade gestacional. Embora não tenha sido evidenciada correlação entre os polimorfismos e os fenótipos estudados, trabalhos futuros com um número amostral maior serão importantes para auxiliar no entendimento do envolvimento de fatores epigenéticos nas síndromes hipertensivas gestacionais e fornecer indícios para a prevenção, o tratamento e o aconselhamento genético. / ARAUJO, F. M. Familial Occurrence and H19 and IGF2 Polymorphism Association with Gestational Hypertensive Disorders. 2007. 118p. Dissertation (Master\'s degree) - University of Medicine, University of São Paulo, Ribeirão Preto, 2007. Gestational hypertensive disorders [preeclampsia/eclampsia (PE/E), gestational hypertension (GH) and chronic hypertension (CH)] are among the largest causes of maternal and fetal death. PE is the more prevalent of those syndromes and the role of the genetic factors in its etiology is well accepted, although the pattern of inheritance is still subject for debate. The imprinted genes H19 and IGF2 are involved in the placental formation and in the fetal development. The objective of the present study was to verify the familial occurrence of these disorders and the H19/RsaI and IGF2/ApaI polymorphism association with gestational hypertensive disorders and the weight of the newborn. All patients of the study were referred to the Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, University of São Paulo, and the project was approved by the Hospital Ethic Committee and the National Commission of Ethics in Research. For the familial study, 226 women were selected (75 presented PE/E, 49 with GH and 102 from the control group). The data were analyzed by Exact of Fisher and Qui-square tests, and the frequency of families with at least one female first-degree relative (mothers and/or sisters) with PE/E was higher among the PE/E group compared to the other groups, and it was statistically significant (P<0.05). There was no statistically significant influence of the \"skin color\". Blood samples of 236 pregnant women (55 with PE/E, 40 with GH, 34 with CH and 107 from the control group) were obtained for DNA extraction, and PCR. Genotyping was carried out by enzymatic digestion with ApaI (IGF2) and RsaI (H19). The statistical analyses were performed by Qui-square and G tests. The genotypes were not significantly associated with the different groups. A higher frequency of the G allele (IGF2) was observed. Around 80% of the patients presented at least one copy of the allele B (H19) and G (IGF2), concomitantly. The association of the weight of the newborn with the polymorphisms was analyzed using the Kolmogorov-Smirnov (P <0.05) and the No-parametric Test of Kruskal-Wallis (P <0.05) tests, and statistically significant differences were not evidenced. In the group of the PE/E there was a statistically significant decrease of the weight of the newborn when the correction for the gestational age was not carried out. Although correlation has not been evidenced between the polymorphisms and the phenotypes, future studies with a higher number of patients and other imprinted genes will be important to elucidate the involvement of epigenetic factors for the prevention, treatment and genetic counseling of the gestational hypertensive disorders

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