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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.
31

Predictive Value of HAS-BLED Score Regarding Bleeding Events and Graft Survival following Renal Transplantation

Hau, Hans Michael, Eckert, Markus, Laudi, Sven, Völker, Maria Theresa, Stehr, Sebastian, Rademacher, Sebastian, Seehofer, Daniel, Sucher, Robert, Piegeler, Tobias, Jahn, Nora 02 November 2023 (has links)
Objective: Due to the high prevalence and incidence of cardio- and cerebrovascular diseases among dialysis-dependent patients with end-stage renal disease (ERSD) scheduled for kidney transplantation (KT), the use of antiplatelet therapy (APT) and/or anticoagulant drugs in this patient population is common. However, these patients share a high risk of complications, either due to thromboembolic or bleeding events, which makes adequate peri- and post-transplant anticoagulation management challenging. Predictive clinical models, such as the HAS-BLED score developed for predicting major bleeding events in patients under anticoagulation therapy, could be helpful tools for the optimization of antithrombotic management and could reduce peri- and postoperative morbidity and mortality. Methods: Data from 204 patients undergoing kidney transplantation (KT) between 2011 and 2018 at the University Hospital Leipzig were retrospectively analyzed. Patients were stratified and categorized postoperatively into the prophylaxis group (group A)—patients without pretransplant anticoagulation/antiplatelet therapy and receiving postoperative heparin in prophylactic doses—and into the (sub)therapeutic group (group B)—patients with postoperative continued use of pretransplant antithrombotic medication used (sub)therapeutically. The primary outcome was the incidence of postoperative bleeding events, which was evaluated for a possible association with the use of antithrombotic therapy. Secondary analyses were conducted for the associations of other potential risk factors, specifically the HAS-BLED score, with allograft outcome. Univariate and multivariate logistic regression as well as a Cox proportional hazard model were used to identify risk factors for long-term allograft function, outcome and survival. The calibration and prognostic accuracy of the risk models were evaluated using the Hosmer–Lemshow test (HLT) and the area under the receiver operating characteristic curve (AUC) model. Results: In total, 94 of 204 (47%) patients received (sub)therapeutic antithrombotic therapy after transplantation and 108 (53%) patients received prophylactic antithrombotic therapy. A total of 61 (29%) patients showed signs of postoperative bleeding. The incidence (p < 0.01) and timepoint of bleeding (p < 0.01) varied significantly between the different antithrombotic treatment groups. After applying multivariate analyses, pre-existing cardiovascular disease (CVD) (OR 2.89 (95% CI: 1.02–8.21); p = 0.04), procedure-specific complications (blood loss (OR 1.03 (95% CI: 1.0–1.05); p = 0.014), Clavien–Dindo classification > grade II (OR 1.03 (95% CI: 1.0–1.05); p = 0.018)), HAS-BLED score (OR 1.49 (95% CI: 1.08–2.07); p = 0.018), vit K antagonists (VKA) (OR 5.89 (95% CI: 1.10–31.28); p = 0.037), the combination of APT and therapeutic heparin (OR 5.44 (95% CI: 1.33–22.31); p = 0.018) as well as postoperative therapeutic heparin (OR 3.37 (95% CI: 1.37–8.26); p < 0.01) were independently associated with an increased risk for bleeding. The intraoperative use of heparin, prior antiplatelet therapy and APT in combination with prophylactic heparin was not associated with increased bleeding risk. Higher recipient body mass index (BMI) (OR 0.32 per 10 kg/m2 increase in BMI (95% CI: 0.12–0.91); p = 0.023) as well as living donor KT (OR 0.43 (95% CI: 0.18–0.94); p = 0.036) were associated with a decreased risk for bleeding. Regarding bleeding events and graft failure, the HAS-BLED risk model demonstrated good calibration (bleeding and graft failure: HLT: chi-square: 4.572, p = 0.802, versus chi-square: 6.52, p = 0.18, respectively) and moderate predictive performance (bleeding AUC: 0.72 (0.63–0.79); graft failure: AUC: 0.7 (0.6–0.78)). Conclusions: In our current study, we could demonstrate the HAS-BLED risk score as a helpful tool with acceptable predictive accuracy regarding bleeding events and graft failure following KT. The intensified monitoring and precise stratification/assessment of bleeding risk factors may be helpful in identifying patients at higher risks of bleeding, improved individualized anticoagulation decisions and choices of antithrombotic therapy in order to optimize outcome after kidney transplantation
32

Léčba ischemické choroby dolních končetin / Treatment of lower extremity peripheral artery disease

Juhász, Jan January 2019 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Jan Juhász Supervisor: Prof. MUDr. Radomír Hrdina, CSc. Title of diploma thesis: Treatment of lower extremity peripheral artery disease The lower extremities ischemia is a disease caused most often by atherosclerosis during which the lumen in lower limb arteries becomes narrow. Its prevalence is increasing, especially in the developed countries. The disease can be asymptomatic and symptomatic. The symptoms are very unpleasant and decrease patient's quality of life. Advanced stages of the disease may be life threatening. Therefore, it is vital to timely and correctly diagnose the illness. During the therapy, it is possible to use pharmacological as well as non-pharmacological procedures, and, preferably, a combination of the two types of treatment. The pharmacotherapy can be divided into several parts. The prevention of atherosclerotic complications makes use of preventive measures and antiplatelet therapy to reduce the cardiovascular risk. The symptoms therapy focuses on improving patients' quality of life by prescribing the vasoactive medications cilostazol, naftidrofuryl or pentoxifylin. The critical limb ischemia therapy uses prostaglandin analogues alprostadil, iloprost, limaprost or...
33

Athérosclérose : approche translationnelle de la détection, caractérisation, et du traitement de la plaque athéromateuse / Atherosclerosis : translational approach of the detection, characterization, and treatment of atheromatous plaque

Didier, Romain 21 June 2018 (has links)
L’athérosclérose est une pathologie artérielle chronique évoluant sur plusieurs années ou dizaines d’années. Sa traduction clinique est variable, pouvant rester longtemps asymptomatique, ou induire des symptômes d’effort directement lié à la réduction du calibre de l’artère (angor, claudication des membres inférieurs). Malgré cette évolution en apparence lente et progressive, les manifestations cliniques aiguës de cette pathologie sont souvent de survenue brutale. La formation de thrombus en regard des lésions athéromateuses dites déstabilisées représente la composante physiopathologique la plus fréquemment rencontrée. Cette complication aigüe de la plaque athéromateuse est responsable d’événements cardio-vasculaires majeurs impactant la morbi-mortalité, représentés par les syndromes coronariens aigus, les accidents vasculaires cérébraux ischémiques, et les ischémies aigues de membre inférieur. Après une revue des connaissances actuelles sur la plaque athéromateuse, nous étudierons à l’aide d’un modèle animal d’athérosclérose, son évolution, ses caractéristiques morphologiques, et nous testerons l’impact d’un traitement au long cours par statine en prévention primaire sur les plaques athéromateuses et sur les composants de la paroi vasculaire. Puis, dans une approche clinique, nous nous intéresserons à la durée optimale du traitement par double antiagrégant plaquettaire instauré après un traitement par angioplastie percutanée de plaque athéromateuse. Dans un second temps, nous détaillerons l’évolution des pratiques d’angioplastie coronaire en analysant les facteurs ayant contribué à limiter l’utilisation des stents non actifs (dit nus) au cours des 10 dernières années. Enfin, nous étudierons les principaux facteurs restant associés à la survenue d’un accident vasculaire cérébral post angioplastie percutanée, correspondant à l’une des principales complications majeures de ces procédures. / Atherosclerosis is a chronic arterial disease that progresses over several years or decades. Its clinical translation is variable, and may remain asymptomatic for a long time, or induce symptoms of stress directly related to the reduction in size of the artery (angina, chronic limb ischemia). Despite this seemingly slow and progressive evolution, the acute clinical manifestations of this pathology often occur suddenly. Thrombus formation in regard to the “destabilized” atheromatous lesions is the most frequently physiopathological components. This acute complication of atheromatous plaque is responsible of major cardiovascular events impacting the morbi-mortality, mostly represented by acute coronary syndromes, ischemic strokes, and acute lower limb ischemia. After a review of current knowledge on atheromatous plaque, we will study using an animal model of atherosclerosis, its evolution, its morphological characteristics, and we will test the impact of a long-term statin treatment in primary prevention on atheromatous plaques and on vascular wall components. Then, in a clinical approach, we will look at the optimal duration of double platelet antiaggregant after angioplasty. In a second step, we will detail the evolution of coronary angioplasty practices by analyzing the main factors that have contributed to limiting the use of bare metal stent over the past 10 years. Finally, we will analyze the major factors still associated with the occurrence of a stroke after percutaneous angioplasty.
34

Étude de l’effet des médicaments antiplaquettaires sur la fonction plaquettaire : de la variabilité de réponse à l’effet rebond

Lordkipanidzé, Marie 12 1900 (has links)
En inhibant la formation de caillots dans le sang, les médicaments antiplaquettaires diminuent de façon importante le risque d’événements ischémiques aigus. Cependant, une sous-population de patients souffrant de maladie coronarienne présente une inhibition inadéquate de la fonction plaquettaire malgré la prise quotidienne d’acide acétylsalicylique (AAS). Le premier volet de cette thèse démontre qu’une régénération plaquettaire accélérée pourrait expliquer en partie la variabilité dans la persistance de l’effet antiplaquettaire de l’AAS chez certains sujets souffrant de maladie coronarienne. Ces données suggèrent qu’une augmentation de la fréquence d’administration d’AAS d’une à deux fois par jour pourrait être bénéfique chez ces sujets. Des méta-analyses ont suggéré qu’une réponse plaquettaire inadéquate à l’AAS pourrait augmenter le risque d’événements ischémiques récurrents. La nature rétrospective de ces analyses ne permet pas d’établir la causalité. Dans le deuxième volet de cette thèse, les résultats d’une étude prospective visant à comparer la pertinence clinique de 6 tests de fonction plaquettaire fréquemment utilisés pour évaluer la réponse plaquettaire à l’AAS est présentée. Les résultats démontrent qu’aucun des tests de fonction plaquettaire couramment employés ne prédit la survenue d’événements ischémiques aigus chez des patients souffrant de maladie coronarienne stable. Toutefois, la cessation de la prise d’AAS est un prédicteur important d’événements thrombotiques. La cessation de médicaments antiplaquettaires a souvent été associée à la survenue d’événements thrombotiques dans les jours suivant l’interruption. À savoir si la survenue de ces événements est attribuable uniquement au retrait d’un médicament protecteur ou plutôt à une sensibilisation plaquettaire, constitue un débat d’actualité. Dans le troisième volet de cette thèse, des données sont présentées démontrant que la cessation de clopidogrel après la période recommandée par les lignes directrices actuelles provoque une sensibilisation des plaquettes nouvellement formées aux stimuli plaquettaires physiologiques. Ces résultats encouragent la recherche sur différentes modalités pour atténuer le risque thrombotique accru chez ces patients souffrant de maladie coronarienne. En conclusion, cet ouvrage présente des études visant à identifier les sous-populations de patients qui sont plus à risque de complications cardiovasculaires récurrentes. Dans ce contexte, la personnalisation de traitement est une avenue thérapeutique prometteuse, où chaque patient pourra recevoir un traitement ciblé en fonction de ses besoins et de ses contre-indications. Ce changement de paradigme d’une thérapie empirique issue d’études de grande envergure sur des données populationnelles à une thérapie ajustée aux besoins individuels représente un vaste champ de recherche, où la majorité des découvertes sont à faire. / By inhibiting the formation of blood clots, antiplatelet drugs significantly reduce the risk of acute ischemic events. However, a subpopulation of patients suffering from coronary artery disease presents with an inadequate inhibition of platelet function despite taking acetylsalicylic acid (ASA) daily. The first part of this thesis demonstrates that accelerated platelet turnover could partly explain the variability in the persistence of the antiplatelet effect of ASA in some coronary artery disease patients. These results suggest that increasing the frequency of administration of ASA from once to twice daily may be beneficial in selected patients. Meta-analyses have suggested that an inadequate platelet response to ASA may increase the risk of recurrent ischemic events. The retrospective nature of these analyses forbids the inference of causality. In the second part of this thesis, the results of a prospective study comparing the clinical relevance of 6 platelet function tests commonly used to assess platelet response to ASA are presented. The results show that none of the commonly used platelet function tests predict the occurrence of acute ischemic events in stable coronary artery disease patients. However, discontinuation of ASA is an important predictor of thrombotic events. Discontinuation of antiplatelet drugs has often been associated with thrombotic events in the days following cessation. If the occurrence of these events is due solely to the withdrawal of a protective drug or rather platelet sensitization is a topic of some debate. In the third part of this thesis, data are presented demonstrating that clopidogrel discontinuation, after the period recommended by current guidelines, leads to sensitization of newly formed platelets to physiological platelet stimuli. These results encourage research on different ways to mitigate the increased risk of thrombosis in coronary artery disease patients scheduled to discontinue clopidogrel therapy. In conclusion, this dissertation presents studies aiming to identify subpopulations of patients who are at increased risk of recurrent cardiovascular events. In this context, the personalization of treatment is a promising therapeutic avenue, where each patient can receive a targeted therapy according to his needs and contraindications. This shift in paradigm from empirical therapy based on population data retrieved from large clinical studies to therapy tailored to individual needs opens a vast field of research, where the majority of discoveries remain to be made.
35

Étude de l’effet des médicaments antiplaquettaires sur la fonction plaquettaire : de la variabilité de réponse à l’effet rebond

Lordkipanidzé, Marie 12 1900 (has links)
En inhibant la formation de caillots dans le sang, les médicaments antiplaquettaires diminuent de façon importante le risque d’événements ischémiques aigus. Cependant, une sous-population de patients souffrant de maladie coronarienne présente une inhibition inadéquate de la fonction plaquettaire malgré la prise quotidienne d’acide acétylsalicylique (AAS). Le premier volet de cette thèse démontre qu’une régénération plaquettaire accélérée pourrait expliquer en partie la variabilité dans la persistance de l’effet antiplaquettaire de l’AAS chez certains sujets souffrant de maladie coronarienne. Ces données suggèrent qu’une augmentation de la fréquence d’administration d’AAS d’une à deux fois par jour pourrait être bénéfique chez ces sujets. Des méta-analyses ont suggéré qu’une réponse plaquettaire inadéquate à l’AAS pourrait augmenter le risque d’événements ischémiques récurrents. La nature rétrospective de ces analyses ne permet pas d’établir la causalité. Dans le deuxième volet de cette thèse, les résultats d’une étude prospective visant à comparer la pertinence clinique de 6 tests de fonction plaquettaire fréquemment utilisés pour évaluer la réponse plaquettaire à l’AAS est présentée. Les résultats démontrent qu’aucun des tests de fonction plaquettaire couramment employés ne prédit la survenue d’événements ischémiques aigus chez des patients souffrant de maladie coronarienne stable. Toutefois, la cessation de la prise d’AAS est un prédicteur important d’événements thrombotiques. La cessation de médicaments antiplaquettaires a souvent été associée à la survenue d’événements thrombotiques dans les jours suivant l’interruption. À savoir si la survenue de ces événements est attribuable uniquement au retrait d’un médicament protecteur ou plutôt à une sensibilisation plaquettaire, constitue un débat d’actualité. Dans le troisième volet de cette thèse, des données sont présentées démontrant que la cessation de clopidogrel après la période recommandée par les lignes directrices actuelles provoque une sensibilisation des plaquettes nouvellement formées aux stimuli plaquettaires physiologiques. Ces résultats encouragent la recherche sur différentes modalités pour atténuer le risque thrombotique accru chez ces patients souffrant de maladie coronarienne. En conclusion, cet ouvrage présente des études visant à identifier les sous-populations de patients qui sont plus à risque de complications cardiovasculaires récurrentes. Dans ce contexte, la personnalisation de traitement est une avenue thérapeutique prometteuse, où chaque patient pourra recevoir un traitement ciblé en fonction de ses besoins et de ses contre-indications. Ce changement de paradigme d’une thérapie empirique issue d’études de grande envergure sur des données populationnelles à une thérapie ajustée aux besoins individuels représente un vaste champ de recherche, où la majorité des découvertes sont à faire. / By inhibiting the formation of blood clots, antiplatelet drugs significantly reduce the risk of acute ischemic events. However, a subpopulation of patients suffering from coronary artery disease presents with an inadequate inhibition of platelet function despite taking acetylsalicylic acid (ASA) daily. The first part of this thesis demonstrates that accelerated platelet turnover could partly explain the variability in the persistence of the antiplatelet effect of ASA in some coronary artery disease patients. These results suggest that increasing the frequency of administration of ASA from once to twice daily may be beneficial in selected patients. Meta-analyses have suggested that an inadequate platelet response to ASA may increase the risk of recurrent ischemic events. The retrospective nature of these analyses forbids the inference of causality. In the second part of this thesis, the results of a prospective study comparing the clinical relevance of 6 platelet function tests commonly used to assess platelet response to ASA are presented. The results show that none of the commonly used platelet function tests predict the occurrence of acute ischemic events in stable coronary artery disease patients. However, discontinuation of ASA is an important predictor of thrombotic events. Discontinuation of antiplatelet drugs has often been associated with thrombotic events in the days following cessation. If the occurrence of these events is due solely to the withdrawal of a protective drug or rather platelet sensitization is a topic of some debate. In the third part of this thesis, data are presented demonstrating that clopidogrel discontinuation, after the period recommended by current guidelines, leads to sensitization of newly formed platelets to physiological platelet stimuli. These results encourage research on different ways to mitigate the increased risk of thrombosis in coronary artery disease patients scheduled to discontinue clopidogrel therapy. In conclusion, this dissertation presents studies aiming to identify subpopulations of patients who are at increased risk of recurrent cardiovascular events. In this context, the personalization of treatment is a promising therapeutic avenue, where each patient can receive a targeted therapy according to his needs and contraindications. This shift in paradigm from empirical therapy based on population data retrieved from large clinical studies to therapy tailored to individual needs opens a vast field of research, where the majority of discoveries remain to be made.
36

BUDDLEJA THYRSOIDES LAM.: ESTUDO MORFOANATÔMICO, FITOQUÍMICO E BIOLÓGICO / BUDDLEJA THYRSOIDES LAM.: MORPHOANATOMIC, PHYTOCHEMICAL AND BIOLOGICAL STUDY

Mahlke, Janaína Dorneles 19 December 2007 (has links)
The Scrophulariaceae family is composed of some 25 genera and more than 1200 species. The genus Buddleja, widely distributed around the world, belongs to this family presently. Buddleja thyrsoides Lam. species, object of study in this work, is distributed in the southern of Brazil region and is popularly known by barbasco and cambarazinho-do-campo. Flowers and leaves decoction are used to treat bronchitis, asthma and cough. The first step of this was the morphoanatomical study of B. thyrsoides leaves aiming to established the identity of the species. The leaves present lanceolate-linear shape, straight adaxial face, serrata to subentire margin and little revolute close to the basis. The epidermis is uniseriate, with the epidermal cells of the adaxial face bigger than those of abaxial face, stomata and trichomes in abaxial face. The mesophyll is heterogeneous, bifacial and presents brachiblasts and crystals in druse form. The vascular system is of the open collateral type. Phytochemical screening showed alkaloids, flavonoids, cumarins, organic acids, antocyanic heterosides, saponins and volatile oils. The antioxidant activities, total phenolic contents, antimicrobial activities, antiplatelet action, acetylcholinesterase enzyme inhibition and toxicity of the crude extract (70% ethanol macerate) and dichloromethane, ethyl acetate and butanolic fractions of Buddleja thyrsoides were investigated. Total phenolic contents varied from 214.07 to 438.4 mg / g. The crude extract and fractions in order of increasing polarity exhibited scavenging activity with IC50 equal to 186.04, 137.70, 146.89, 165.71 μg/mL. A positive correlation between antioxidant activity and total phenolic contents was observed, where the ethyl acetate and dichloromethane fractions had the best results in both tests. The butanolic fraction was effective against S. cerevisiae (62.5 μg / mL for MIC and MFC) in the assessment of antimicrobial activity. The dichloromethane and ethyl acetate fractions were effective against S. aureus (250 and 500 μ g / mL for CIM and CBM), respectively. The crude extract and the fractions of B. thyrsoides did not shown toxicity against Artemia salina. The fractions (in order of increasing polarity) and crude extract showed antiplatelet action (42.35, 40.68, 43.57 and 41.52% respectively), whereas the AAS afforded 58.36% of inhibition. The crude extract inhibited in 22.77% the acetylcholinesterase enzyme after 24 hours. The major components of the essential oil were germacreno D (27.16%), 1,10-di - epi-cubenol (13.37%) and α - Cadinol (12.95%), biciclogermacreno (9.00%), δ - cadineno (8.59%) and cariofileno E (5.26%). / A família Scrophulariaceae é composta por cerca de 25 gêneros e mais de 1200 espécies. O gênero Buddleja, amplamente distribuído pelo mundo, atualmente, pertence a esta família. A espécie Buddleja thyrsoides Lam., objeto de estudo neste trabalho, encontra-se distribuída na região sul do Brasil e é conhecida popularmente por barbasco e cambarazinho-docampo. A decocção das flores e folhas é utilizada para bronquite, asma e tosse. Este trabalho objetiva em identificar morfoanatomicamente as folhas de B. thyrsoides, bem como analisar alguns parâmetros farmacológicos e biológicos para esta espécie. As folhas apresentam formato linear-lanceolado, face adaxial lisa, margem serreada até subinteira e pouco revoluta próxima à base. A epiderme é uniseriada, com as células epidérmicas da face adaxial maiores do que na face abaxial, estômatos e tricomas na face abaxial. O mesofilo é heterogêneo, bifacial e apresenta braquiblastos e cristais na forma de drusas. O sistema vascular é do tipo colateral aberto. Na análise fitoquímica foram detectados alcalóides, flavonóides, cumarinas, ácidos orgânicos, heterosídeos antociânicos, saponinas e óleos voláteis. O extrato bruto (de um macerado etanólico a 70 %) e frações diclorometano, acetato de etila e butanólica de Buddleja thyrsoides foram investigados quanto à atividade antioxidante, conteúdo de fenólicos totais, atividade antimicrobiana, ação antiagregante, inibição da enzima acetilcolinesterase e quanto à toxicidade. O conteúdo de fenólicos totais variou de 214,07 a 438,4 mg/g. O CI50 da atividade antioxidande para o extrato bruto e frações em ordem crescente de polaridade (186,04; 137,70; 146,89; 165,71 μg/mL). Foi observada uma correlação positiva entre a atividade antioxidante e o conteúdo de fenólicos totais, onde as frações acetato de etila e diclorometano apresentaram os melhores resultados em ambas análises. Na avaliação da atividade antimicrobiana, a fração butanólica foi efetiva contra S. cerevisae (62,5 μg/mL para CIM e CFM). As frações diclorometano e acetato de etila foram eficazes contra o S. aureus (250 e 500 μg/mL para CIM e CBM), respectivamente. O extrato bruto e as frações de B. thyrsoides não apresentaram toxicidade frente Artemia salina. As frações (em ordem crescente de polaridade) e extrato bruto mostraram ação antiagregante plaquetária (42,35; 40,68; 43,57 e 41,52 %, respectivamente), sendo que o AAS apresentou 58,36 % de inibição. O extrato bruto inibiu em 22,77 % a enzima acetilcolinesterase após 24 horas. Os componentes majoritários do óleo essencial são Germacreno D (27,16%), 1,10-di-epi-Cubenol (13,37 %) e α-Cadinol (12,95 %), Biciclogermacreno (9,00 %), δ-cadineno (8,59 % ) e Cariofileno E (5,26%).
37

Low-dose aspirin therapy in IVF and ICSI patients

Haapsamo, M. (Mervi) 29 November 2011 (has links)
Abstract The first aim of this randomized, placebo-controlled and double-blind study was to investigate whether low-dose aspirin therapy, started prior to controlled ovarian hyperstimulation, improves ovarian stimulation response, uterine haemodynamics and clinical pregnancy rates in unselected patients who underwent in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). The second aim was to examine if the maternal serum placental proteome is different in IVF/ICSI pregnancies compared with spontaneous pregnancies, and whether low-dose aspirin modifies maternal serum placental protein expression and uteroplacental haemodynamics during the first half of pregnancy. Finally, the effect of low-dose aspirin therapy on the incidence of hypertensive pregnancy complications among women who became pregnant after IVF/ICSI was investigated. Low-dose aspirin therapy did not increase the number of oocytes retrieved, the total number of embryos or number of top-quality embryos, endometrial thickness or uterine haemodynamics on the day of embryo transfer (ET) or clinical pregnancy rates compared with placebo-treated IVF/ICSI women. On the day of ET, low-dose aspirin did not affect UtA vascular impedance, but the incidence of non-optimal uterine artery haemodynamics (UtA PI&#8805;3.0) was statistically significantly lower (p&#60;0.05) in the aspirin group compared with the placebo group. In the placebo-treated IVF/ICSI patients, maternal serum proteome analysis showed altered protein expression compared with women with spontaneous pregnancies. Between aspirin- and placebo-treated IVF/ICSI patients, proteome analysis showed a unique and distinct pattern of differentially expressed proteins including extra-cellular matrix, complement and transport proteins. At 6 weeks’ gestation, arcuate artery PI and at 18 weeks’ gestation, UtA PI values were lower (p&#60;0.05) in the aspirin group than in the placebo group. In conclusion, low-dose aspirin therapy, when started concomitantly with controlled ovarian hyperstimulation, did not improve ovarian responsiveness, uterine receptivity, pregnancy outcome in unselected IVF/ICSI women or affect UtA vascular impedance on the day of ET. Low-dose aspirin modified the early placentation process and reduced uteroplacental vascular impedance in mid-pregnancy, but did not decrease the incidence of hypertensive pregnancy complications. / Tiivistelmä Keinoalkuisten hedelmöityshoitojen seurauksena keskimäärin reilu kolmannes naisista tulee raskaaksi hoitokertaa kohti. Näissä raskauksissa äidin seerumista määritettyjen istukkaperäisten merkkiaineiden pitoisuuksissa on eroavaisuuksia verrattuna spontaanisti raskaaksi tulleiden naisten seerumipitoisuuksiin ensimmäisen ja toisen raskauskolmanneksen aikana. Pre-eklampsian eli raskausmyrkytyksen riski on myös lisääntynyt. Syyksi arvellaan istukan verisuonipuuston poikkeavaa kehitystä. Pre-eklampsiaan liitetään intravaskulaarisen prostasykliinin ja tromboksaanin epätasapaino, joka johtaa verihiutaleiden aggregaation lisääntymiseen ja verisuonten supistumiseen. Matala-annoksinen asetyylisalisyylihappo (ASA) vähentää tromboksaanituotantoa ja korjaa tromboksaani- ja prostasykliinituotannon epätasapainoa, mutta sen ei ole todettu merkittävästi vähentävän näiden raskauskomplikaatioiden esiintyvyyttä edes riskiryhmillä, kun lääkitys on aloitettu toisen raskauskolmanneksen aikana. Tämän satunnaistetun ja plasebo-kontrolloidun kaksoissokkotutkimuksen tavoitteena oli tutkia keinoalkuisia hedelmöityshoitoja saavilla naisilla matala-annoksisen ASA-hoidon (100 mg/vrk) merkitystä munasarjojen stimulaatiovasteeseen, alkion kiinnittymiseen, istukan muodostumiseen ja kehittymiseen sekä lääkehoidon vaikutusta kohdun, istukan ja sikiön verenkiertoon, kun lääkitys aloitettiin munasarjojen stimulaatiohoidon alkaessa. Lisätavoitteena oli selvittää, onko lapsettomuushoitoja saavien naisten raskauksissa todettavissa spesifinen istukkaproteomiikkalöydös (istukan tuottamat valkuaisaineet) verrattuna spontaanisti raskaaksi tulleisiin naisiin ja voidaanko siihen vaikuttaa matala-annoksisella ASA-hoidolla. Toisena lisätavoitteena oli selvittää matala-annoksisen ASA-hoidon vaikutus pre-eklampsian esiintyvyyteen loppuraskaudessa. Matala-annoksinen asetyylisalisyylihappo (ASA) ei paranna keinoalkuisten hedelmöityshoitojen hoitotuloksia eikä vaikuta kohdun verenkiertoon tai kohdun limakalvon paksuuteen ultraäänellä arvioituna alkion siirtopäivänä. Matala-annoksista ASA-hoitoa käyttäneiden potilaiden ryhmässä todettiin kuitenkin merkitsevästi vähemmän naisia, joilla oli huonoa hoitotulosta keinoalkuisissa hedelmöityshoidoissa ennakoiva korkea molemminpuolinen kohtuvaltimoiden verenvirtausvastus alkion siirtopäivänä verrattuna plasebo-ryhmään. Raskaaksi tulleilla naisilla, jotka käyttivät matala-annoksista ASA-hoitoa, todettiin kohdun verenvirtausvastus matalammaksi alku- ja keskiraskaudessa verrattuna plasebo-ryhmän naisiin. Istukkaproteomiikkatutkimusten mukaan varhaisistukan proteiinituotanto on erilainen keinoalkuisissa raskauksissa verrattuna spontaanisti alkaneisiin raskauksiin ja siihen voidaan vaikuttaa matala-annoksisella ASA-hoidolla. Pre-eklampsian ja sikiön kasvunhidastuman esiintyvyydessä ei ryhmien välillä todettu eroa. Matala-annoksinen ASA-hoito aloitettuna ennen raskautta munasarjojen stimulaatiohoidon alkaessa ei paranna munasarjojen vastetta lapsettomuushoidoissa käytettäville hormonihoidoille, raskauslukuja eikä kohdun verenkiertoa alkion siirtopäivänä. Hoidon todettiin kuitenkin vaikuttavan varhaisistukan kehittymiseen sekä parantavan kohdun verenkierto alku- ja keskiraskaudessa viitaten istukan verisuonipuuston parempaan kehittymiseen. Matala-annoksinen ASA-hoito ei vähentänyt istukkaperäisten raskauskomplikaatioiden esiintymistä.
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Evaluation pharmaco-épidémiologique de la combinaison thérapeutique recommandée en prévention secondaire cardiovasculaire / Pharmacoepidemiological evaluation of the recommended drug combination in cardiovascular secondary prevention

Bezin, Julien 05 December 2016 (has links)
En France, le syndrome coronaire aigu (SCA) représente environ 100 000 hospitalisations par an. Il est recommandé, en prévention secondaire du SCA, un traitement combinant quatre classes médicamenteuses : bêtabloquants, antiagrégants plaquettaires, statines, et inhibiteurs de l’enzyme de conversion ou antagonistes des récepteurs à l’angiotensine II(combinaison BASI). L’objectif de ce travail était l’étude, en situation réelle de soin et en population générale, de l’utilisation et de l’effectivité de la combinaison thérapeutique recommandée en prévention secondaire du SCA. Nous avons d’abord exploré le potentiel représenté par les bases de données médicoadministratives françaises pour cette évaluation. Nous avons ensuite étudié l’utilisation de la combinaison BASI : 42 % des patients étaient traités par la combinaison BASI en post-SCA et 57 % d’entre eux étaient encore traités à deux ans ; la persistance au traitement était plus faible chez les patients âgés, chez ceux ayant d’autres co-morbidités et chez ceux ayant eu un SCA de nature autre qu’un infarctus du myocarde.Nous avons enfin étudié l’effectivité de la combinaison BASI : la combinaison BASI était la combinaison thérapeutique la plus effective à long terme après un SCA chez les patients avec antécédent d’insuffisance cardiaque ; chez les patients sans antécédent de ce type la combinaison sans bêtabloquants n’était pas associée à une augmentation du risque.Ces résultats permettent de reconsidérer l’intérêt à long terme de l’ensemble de la combinaison BASI en post-SCA chez tous les patients et mettent en avant la nécessité de renforcer les stratégies d’éducation thérapeutique. / Acute coronary syndrome (ACS) causes approximately 100,000 hospitalisations per year in France. In secondary prevention of ACS, guidelines advocate pharmacological treatment combining four drug classes: beta-blockers, antiplatelet agents, statins and angiotensin converting enzyme inhibitors or angiotensin receptor blockers (recommended combination).The aim of this work was to study, in real life and among the general population, the use and the effectiveness of the recommended combination for secondary prevention of ACS.Firstly, we explored the potential represented by the French claims databases in this context. Secondly, we studied the use of the recommended combination: 42% of patients were treated with the recommended combination in post-ACS and 57% of them were still treated two years after; persistence to combination was lower in older patients, in those with other comorbidities and those who had an ACS different of myocardial infarction. Thirdly, we studied the effectiveness of the recommended combination: the recommended combination was the most effective combination therapy at long-term in post-ACS patients with history of heart failure; in patients without such history the combination without betablockers was not associated with an increased risk. These results could help reconsidering the long-term interest of the full recommended combination in all ACS patients and highlight the need to strengthen patient education strategies.
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Le cœur métabolique : la métabolomique afin de mieux caractériser l’infarctus du myocarde

Samman, Karla N. 12 1900 (has links)
Dans les syndromes coronariens aigus, le ticagrelor améliore la survie comparativement au clopidogrel. Les effets pléiotropiques de ce médicament ne sont pas entièrement compris. La métabolomique non ciblée, couplée avec des analyses computationnelles, a le potentiel d’élucider les changements pathophysiologiques du métabolisme cellulaire associés aux différentes maladies et aux traitements. L’objectif de cette étude est de dévoiler une signature métabolomique discriminante entre le clopidogrel et le ticagrelor dans le traitement de l’infarctus du myocarde avec élévation du segment ST (STEMI). La population de l’étude est formée de 175 participants de l’essai PLATO avec STEMI ayant subi une intervention percutanée (PCI), randomisés à recevoir le clopidogrel (n=88) ou le ticagrelor (n=87), appariés pour l’âge, le sexe, le statut de dyslipidémie et de diabète. Un profil métabolomique plasmatique non ciblé, obtenu par spectrométrie de masse (MS), est effectué pour chaque individu à l’état de base (BL; maladie aiguë) et au congé de l’hôpital après en moyenne 4 jours d’hospitalisation (DC; état post-traitement). L’étude des données a été effectuée par une analyse de quantification différentielle, une analyse de la variance, la construction d'un réseau de co-modulation et des techniques d'apprentissage automatique. Huit (8) métabolites étaient modulés de façon différentielle entre les deux groupes de traitement au congé, dont six (6) appartenant aux voies de biosynthèse des acides gras polyinsaturés omega-3 (n3) et omega-6 (n6). Les participants traités avec ticagrelor présentent des niveaux plasmatiques significativement plus élevés des acides gras suivants : α et de γ-linolénate (n3 and n6), dihomo-linolénate (n6), stéaridonate (n3), docosahexaenoate (DHA; n3), eicosapentaenoate (EPA; n3) et arachidonate (AA; n6). Chez les patients avec STEMI traités par PCI, des analyses de métabolomique non ciblées révèlent que les métabolites impliqués dans la biosynthèse des omega-3 et des omega-6 sont significativement plus élevé au congé dans le groupe traité par le ticagrelor, comparativement au clopidogrel, suggérant que le remodelage du réseau métabolique après un infarctus du myocarde pourrait interagir avec la réponse aux antiplaquettaires. / Background: In acute coronary syndromes, ticagrelor improved survival compared to clopidogrel. Pleiotropic effects of this drug are not entirely elucidated. Untargeted metabolomics coupled with computational analyses has the potential to help understanding pathophysiological changes of cellular metabolism associated with different disease states and therapies. Objectives: The purpose of this study is to unveil a discriminant metabolomics signature comparing ST-elevation myocardial infarction (STEMI) patients treated with clopidogrel and ticagrelor. Methods: The study population consists of 175 participants with STEMI from the PLATO Trial who underwent percutaneous coronary intervention (PCI), randomized to receive clopidogrel (n=88) or ticagrelor (n=87), matched for age, sex, dyslipidemia and diabetes status. Untargeted mass spectrometry (MS)-based metabolomics profiling in plasma was performed at baseline (BL; acute disease state) and repeated at hospital discharge after an average of 4 days of hospitalization (DC; post-treatment state), for each individual. Data analysis was done through differential quantification analysis, analysis of variance, co-modulation network construction and machine learning techniques. Results: Eight (8) metabolites were differentially modulated by treatment between groups at DC, six (6) of which belong to the polyunsaturated fatty acids omega-3 (n3) and omega-6 (n6) biosynthesis pathways. Participants treated with ticagrelor harbor a significantly higher plasmatic level of α and γ linolenate (n3 and n6), dihomo-linolenate (n6), stearidonate (n3), docosahexaenoate (DHA; n3), eicosapentaenoate (EPA; n3) and arachidonate (AA; n6). Conclusion: In patients with STEMI undergoing PCI, untargeted metabolomics reveals that metabolites involved in omega-3 and omega-6 biosynthesis are significantly higher at discharge in the ticagrelor treatment group when compared to clopidogrel, suggesting that the remodeling of the metabolic network after myocardial infarction may interact with the response to antiplatelet drugs.
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The effect of crude water extracts of Tulbaghia violacea Harv. on scaffolds with cardiovascular applications

Madike, Lerato Nellvecia 02 1900 (has links)
PhD (Department of Biotechnology, Faculty of Applied and Computer Sciences), Vaal University of Technology. / Tulbaghia violacea Harv. has found extensive uses in traditional medicine for the treatment of numerous ailments among which are tuberculosis, oesophageal cancer, diabetes and cardiovascular diseases. Current reports show that cardiovascular diseases are now the primary cause of mortality worldwide. Thus, the potential of T. violacea plant extracts against cardiovascular diseases should be explored. The objectives of this study were, (i) to conduct qualitative and quantitative preliminary phytochemical screening of T. violacea aqueous leaf extracts, (ii) to conduct Gas chromatography–mass spectrometry (GC-MS) analysis for screening of compounds present in the plant extract, (iii) to evaluate the antioxidant activity of the T. violacea crude extracts using the DPPH:1.1-diphenyl-2-picrylhydrazyl and ABTS: 2,2-azino-bis 3-ethylebenzthiazoline-6-sulfonic acid assays, (iv) to evaluate the antimicrobial activity of the T. violacea crude extracts using disk diffusion and Minimum inhibitory concentration/Minimum bactericidal concentration (MIC/MBC), (v) to evaluate the antithrombogenic properties of T. violacea crude extracts on polystyrene, (vi) to fabricate polycaprolactone (PCL) and PCL-T. violacea incorporated scaffolds, (vii) to evaluate the antithrombogenic properties of T. violacea crude extracts on the fabricated PCL and PCL-T. violacea fabricated scaffolds and, (viii) to evaluate the growth and differentiation of adipose derived stem cells (ADSCs) on the fabricated scaffolds. The qualitative and quantitative phytochemical screening was conducted using standard procedures. Folin-Ciocalteu method was used to evaluate both total phenolic content (TPC) and total tannin content (TTC), the Aluminium chloride method was used for total flavonoid content (TFC) and GC-MS was used to screen for compounds present in the plant extract. The antioxidant activity was evaluated using DPPH and ABTS and the antimicrobial activity was evaluated using disc diffusion and MIC/MBC assays. The antithrombogenic properties of the T. violacea aqueous leaf extracts was then evaluated using platelet activation and whole blood clotting kinetics on polystyrene discs which have been reported to induce platelet activation. The experiment was performed in the absence and presence of 100 and 1000 μg/ml T. violacea plant extracts for both the platelet activation study which used blood plasma and the whole blood clotting kinetics assay which used fresh whole blood. Platelet adhesion was evaluated using fluorescence microscopy and a scanning electron microscope (SEM) was used to evaluate their morphology. Three scaffolds designated as PCL, 10% Tvio and 15% Tvio were fabricated which consisted of a 10% PCL powder and 10% as well as 15% T. violacea aqueous plant extract with respect to the PCL powder weight. The scaffolds were then characterized using Fourier-transform infrared spectroscopy (FTIR) and Energy-dispersive x-ray spectroscopy (EDS). The scaffolds were then evaluated for their antithrombogenic properties in the presence and absence of 100 and 1000 μg/ml T. violacea plant extracts. Platelet adhesion was evaluated using a fluorescent microscope and the morphology was evaluated using SEM. For the cell study, adipose derived stem cells (ADSCs) were cultured on the designed scaffolds and evaluated for their toxicity, viability, adhesion, proliferation, morphology and differentiation into osteoblasts over a period of 3 weeks. Lactate dehydrogenase (LDH) assay was used for toxicity studies, alamar blue assay was used for viability, fluorescence microscopy was used to evaluate cellular adhesion and proliferation while the alkaline phosphate (ALP) assay was used to evaluate differentiation of the cells into osteoblasts. Cell morphology was evaluated using SEM. Phytochemical screening of the prepared T. violacea aqueous extract revealed the presence of terpenoids, flavonoids, cardiac glycosides, saponins, protein, phenols, tannins, carbohydrates and amino acids. This is the first study that has identified the presence of carbohydrates and amino acids in T. violacea aqueous leaf extracts. Different concentrations of 0.1, 1.0 and 10 mg/ml of plant extract were used to conduct the quantitative phytochemical screening assays. There was a concentration dependent increase in the amount of phenols, tannins and flavonoids as the concentration of the plant extracts increased. This was the first study that evaluated the total tannic content of T. violacea plant extracts. The amount of total phenols was higher than that of flavonoids and tannins at every concentration range studied followed by the total flavonoids and lastly total tannins. The GC-MS analysis showed the presence of 33 compounds among which were 2,4 – Dithiapentate - 2,2-dioxide, Cannabidiol, 2,4,5,7 –Tetrathiaoctane and 2,4,5,7 - Tetrathiaoctane 2-dioxide. The presence of sulphur compounds support the characteristic garlic-like smell as well as some of the biological activities of T. violacea plant extracts. The antioxidant activities based on DPPH (0.49 mg/ml) and ABTS (0.24 mg/ml) suggest that T. violacea can be used as potential antioxidant agents. For the antimicrobial activity using disc diffusion, the extracts exhibited appreciable antibacterial activities against Bacillus subtilis, Serratia marcescens, Staphylococcus aureus and S. epidermidis. The highest zone of inhibition was observed for S. epidermidis at 19.50 ± 0.87 mm. The MIC results revealed that the plant extract of T. violacea was moderately active against B. subtilis, S. aureus, S. epidermidis, E. coli, and S. marcescens with MIC value of 2.5 mg/ml. However, the antimicrobial effect of the extract on S. epidermidis was bactericidal when compared to the bacteriostatic effect on the other active microorganisms. The antithrombogenic results on the polystyrene discs showed a significant reduction in the number of platelets that adhered on the polystyrene surfaces treated with plasma mixed with 100 μg/ml of plant extract when compared to the untreated control and the 1000 μg/ml treatment. For the 1000 μg/ml treatment, there was a significant increase in the number of platelets that adhered to polystyrene surfaces. These results were confirmed by the fluorescence and SEM results which showed a higher platelet count for the 1000 μg/ml treatment when compared to the other groups. The whole blood clotting kinetics study showed delayed blood clotting with the 100 μg/ml treatment over a period of 60 min when compared to the untreated control and the 1000 μg/ml treatment. These results correspond with the lower platelet adhesion observation and thus confirm the anticlotting properties of T. violacea aqueous leaf extracts at lower concentrations. The mean diameter of the scaffolds was recorded on the SEM as 275.60 ± 60.65 nm, 193 ± 30 nm and 537 ± 138 nm for the PCL, 10% Tvio and 15% Tvio scaffolds, respectively. The FTIR spectrum revealed the presence of amide groups as well hydroxyl O–H stretching groups which were the characteristic groups for the presence of T. violacea plant extracts in the polycaprolactone. The EDS results showed the presence of potassium, chlorine and sulphur compounds which were only present in the T. violacea scaffolds in addition to the carbon, oxygen and silicon observed in the PCL scaffold. The fabricated scaffolds were then used to evaluate platelet adhesion and activation on blood plasma in the absence and presence of 100 and 1000 μg/ml T. violacea aqueous leaf extracts. The results showed that the 10% Tvio scaffold was more effective in inhibiting platelet adhesion and activation at every treatment group especially when plasma was used in the absence of T. violacea plant extracts. A similar observation to the polystyrene study was observed were addition of 1000 μg/ml of plant extract resulted in the highest number of activated platelets. The study suggests the potential of the 10% Tvio scaffold in the prevention of platelet adhesion and aggregation. The in vitro cell adhesion, proliferation and differentiation of adipose derived stem cells (ADSCs) on the fabricated T. violacea loaded PCL nanofibers was then evaluated. The LDH assay illustrated less activity on the 10% Tvio scaffold when compared to PCL and 15% Tvio scaffolds however, none of the scaffolds were considered as toxic. The alamar blue assay was used for viability after 4 and 7 days of culture. The results showed a significant increase in cell viability for all scaffolds from day 4 to day 7 with the 10% Tvio scaffold having the highest overall cell viability for both day 4 and day 7 of cell cultures. Immunofluorescence staining was then used to count the number of cells using DAPI (4′,6-diamidino-2-phenylindole) stained images and illustrated that the T. violacea incorporated scaffolds supported better cell growth compared to the PCL scaffold. Cell morphology on the T. violacea scaffolds was denser and spread out into cellular extensions when compared to the PCL scaffold after 7 days of cell culture, supporting the higher number of adhered cells from the fluorescence results. For the long term cell study after week 1 and 3, the ALP results showed a significant difference in ALP activity between week 1 and week 3 for all scaffolds. The highest ALP activity was observed for the 15% Tvio scaffolds which is a marker for initial phase of bone matrix deposition. The designed T. violacea scaffolds supported better cell growth compared to the PCL scaffold and their morphology was more spread out and covered the entire surface of the scaffolds after week 3. Lastly, the cell count and osteocalcin differentiation was more prominent on 10% Tvio scaffold indicating higher levels of the protein marker for bone formation. Thus, supporting the use of the 10% Tvio scaffold for long-term cell studies. In conclusion, the results of this study indicated that the aqueous extract of T. violacea is rich is phytochemicals and also possess a broad range of pharmaceutically important compounds which may be attributed to the high antioxidant and antimicrobial activities identified. The results from this study suggest that T. violacea aqueous extracts have antithrombogenic properties at lower concentrations. Scaffolds fabricated with the incorporation of T. violacea plant extract also confirm the potential antiplatelet activity of the fabricated 10% Tvio scaffold. The results also suggest the potential of the fabricated 10% Tvio scaffold to enhance cell adhesion, proliferation and differentiation over long-term cell studies. It can thus be recommended that T. violacea may be useful for tissue engineering applications and bone repair with prospects of preventing cardiovascular diseases associated with bone defects. This research study has provided the foundation for clinical evaluation and outlined the potential effects of T. violacea aqueous leaf extracts as a clinical drug.

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