Annals of medicine
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Since selective cyclooxygenase-2 inhibitors (coxibs) entered the market, there has been concern about the cardiovascular safety of coxibs. In addition, recent data suggest that classical non-steroidal anti-inflammatory drugs (NSAIDs) have a similar cardiovascular risk. Importantly, all of the clinical trials with NSAIDs and coxibs so far were not purpose-designed to specifically and prospectively address cardiovascular safety and were clearly underpowered to detect any meaningful differences. In this current uncertainty about safety of NSAIDs and coxibs, the definitive answer as to the net effect of coxibs and NSAIDs on cardiovascular events can only be provided by well designed adequately powered, long-term clinical trials, which is now under way.
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Cardiovascular disease is associated with damage of the endothelial monolayer leading to endothelial dysfunction and atherosclerosis. A growing body of evidence suggests that circulating endothelial progenitor cells play an important role in endothelial cell regeneration. In this review we discuss the evolving role of stem- and progenitor cells in the maintenance of the vascular wall focusing on new pathophysiological concepts of endothelial cell regeneration. We discuss new insights into vascular stem cell biology derived from experimental and clinical studies.
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Despite the fact that the heart requires huge amounts of energy to sustain contractile function, it has limited energy reserves and must therefore continually produce large amounts of adenosine triphosphate (ATP) to sustain function. Fatty acids are the primary energy substrate of the adult heart, with more than 60% of the energy normally obtained from the oxidation of fatty acids, the remainder coming from the metabolism of carbohydrates. Alterations in both the rates of ATP production and the type of energy substrate used by the heart can have consequences on contractile function, as well as on its ability to respond to energetic stresses. ⋯ Heart failure is characterized by an inefficient pumping of the heart, which fails to meet the energy requirements of the body. A number of cardiomyopathies can lead to heart failure. This paper will review the alterations in energy metabolism that occur in a number cardiomyopathies, including ischemic and diabetic cardiomyopathies, as well as hypertrophic cardiomyopathies resulting from mutations in enzymes involved in energy metabolism, such as 5' adenosine monophosphate-activated protein kinase (AMPK).
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The prevalence of immunoglobulin E (IgE)-mediated allergic diseases has been increasing for the last four decades. In this review determinants for an increased IgE synthesis are discussed on both an epidemiological and on an immunological level with special emphasis on the differentiation of the B cell to an IgE-producing plasma cell. Factors that favor an IgE immune response are low antigen doses and immunization via mucous membranes, but it is highly likely that other environmental factors besides exposure to the allergenic sources play a role. ⋯ In order for a B lymphocyte to switch to IgE production it needs two signals provided by a Th2 cell in the form of the cytokines interleukin (IL-) 4/IL-13 and ligation of the CD40. In spite of a half-life of only a few days, there is evidence that the IgE response may last for years even without allergen stimulation. This is likely to be caused by long-lived IgE-producing plasma cells, and such cells may be difficult to target therapeutically thus emphasizing the need for more knowledge on preventable causes of IgE- and allergy development.
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The thrombin-catalysed conversion of plasma fibrinogen into fibrin and the development of an insoluble fibrin clot are the final steps of the coagulation cascade during haemostasis. A delicate balance between coagulation and fibrinolysis determines the stability of the fibrin clot. Thrombin plays a central role in this process, it not only forms the clot but it is also involved in stabilizing the clot by activating thrombin activatable fibrinolysis inhibitor (TAFI). ⋯ Vice versa an increased activation of TAFI due to an increased rate of thrombin generation might lead to thrombotic disorders. Specific inhibitors of activated TAFI or inhibitors that interfere with the generation of thrombin might provide novel therapeutic strategies for thrombolytic therapy. Besides having a role in the regulation of fibrinolysis, TAFI may also have an important function in the regulation of inflammation, wound healing and blood pressure.