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Some forms of early ECG repolarization QRS pattern (ERp) with J‐point elevation of 0.1 mV in two contiguous inferior and/or lateral leads with or without ST‐elevation are potentially associated with a higher arrhythmic risk in adults. We assessed the prevalence of ERp among non‐professional adolescent athletes and correlated it with age, sex, ethnicity, and structural and electric cardiac parameters. We retrospectively analyzed 414 ECGs obtained from young athletes referred to our center from 2006 to 2017. We found ERp in 22% of cases. In the ERp group, we found a greater percentage of black athletes, a higher systolic blood pressure, and lower heart rate (HR) compared with the group without ERp. This pattern was less frequent in female athletes. In athletes with ERp, the occurrence of ventricular ectopic beats was less frequent and QRS‐duration was shorter. They also exhibited greater (a) ECG‐based left ventricular hypertrophy (LVH), (b) left ventricular mass, and (c) relative wall thickness (RWT), suggesting a tendency to concentric geometry. At logistic regression analysis, we found that HR (OR 0.98 [0.96‐0.99] P = .013), QRS‐duration (OR 0.96 [0.94‐0.99], P = .003), LVH (OR 1.09 [1.05‐1.12], P < .001), and RWT (OR 1.08 [1.01‐1.16] P = .032) were significant predictors of ERp incidence. ERp is quite common in adolescent athletes and correlates with concentric LV remodeling. Specific clinical and ECG‐findings related to training such as lower HR, LVH, and QRS‐duration are also predictors of ERp. In adolescent non‐professional athletes, ERp is a benign finding associated with some structural and electric cardiac modifications induced by training.  相似文献   
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Introduction: Colloidal drug delivery systems (CDDSs) are innovative carriers that have been studied in pharmaceutical field from many years to overcome unfavorable physical and chemical features of synthetic drugs. Recently the use of CDDS as carriers for phytochemicals has seen an exponential increase which, in some cases, has led to the rediscovery of ancient and forgotten natural molecules.

Area covered: This article focuses on the main features of CDDS, particularly micro- and nanoemulsions, vesicular carriers and micro- and nanoparticles, loaded with natural active compounds. A detailed review of the literature is presented, introducing the importance of these systems in terms of their capability to optimize the stability of phytochemicals, their absorption through biological membranes and their bioavailability.

Expert opinion: The delivery of phytochemicals is problematic due to poor solubility, poor permeability, low bioavailability, instability in biological milieu and extensive first-pass metabolism. Global research efforts investigating nanotechnology have attempted to overcome these limitations rediscovering and, in some cases, ‘discovering ex novo’ unexpected virtues and benefits associated to these compounds. The ‘nanotechnological approach’ can definitely enhance the pharmacokinetics and therapeutic index of natural active compounds and improve their performance in therapy.  相似文献   

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