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Beta-blockers have become one of the cornerstones of treatment of patients with heart failure (HF) and depressed left ventricular function, but in clinical practice only 30–35 % of patients achieve the therapeutic target dose as established in randomized clinical trials. Moreover, high resting heart rate (HR) has emerged as a simple but relevant risk factor for cardiovascular events, including coronary artery disease and HF; also, it was found to have an independent prognostic value in patients with HF. Evidence that HR could be considered a good parameter to evaluate the quality of treatment in patients with HF has been suggested; of note, many patients maintain a resting HR ≥70 beats per minute despite optimal beta-blocker therapy. In recent years, a new drug able to reduce HR, ivabradine, has been introduced in clinical practice, and its use in the clinical setting of HF patients has been recommended by current European Society of Cardiology (ESC) guidelines. Here we review the evidence of the prognostic role of HR in systolic HF and the potential relationship between HR lowering and the beneficial effects of beta-blockers; we will also analyze the reasons why an appropriate use of these drugs is seldom achieved in clinical practice, and review the evidence for the use of ivabradine in systolic HF in the clinical setting.  相似文献   
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Background and aimsDespite elevated serum uric acid (eSUA) has been identified as independent risk factor for cardiovascular diseases, its prognostic value in the setting of ST-segment elevation myocardial infarction (STEMI) is still controversial. Although the mechanisms of this possible relationship are unsettled it has been suggested that eSUA could trigger the inflammatory response. This study sought to investigate the association between eSUA with short- and long-term mortality and with inflammatory response in patients with STEMI treated with primary percutaneous coronary intervention (pPCI).Methods and resultsBlood samples were collected on admission and at 24 and 48 h after pPCI: the inflammatory biomarkers C-reactive protein (CRP), neutrophil count and neutrophil to lymphocytes ratio (NLR) were considered. Baseline eSUA was defined as ≥6.8 mg/dl. Cumulative 30-days and 1-year mortalities were estimated using the Kaplan-Meyer analysis. Multivariable analyses were performed by Cox proportional hazard models.In the 2369 patients with STEMI considered, 30-day mortality was 5.8% among patients with eSUA and 2% among patient with normal SUA level (p < 0.001); 1-year mortality was 8.5% vs 4%, respectively (p < 0.001). At multivariable analyses eSUA was an independent predictor of 30-day mortality (HR 1.196, 95%CI 1.006–1.321, p = 0.042) and 1-year mortality (HR 1.178, 95%CI 1.052–1.320, p = 0.005). eSUA patients presented higher values in on admission CRP (p < 0.001) and in neutrophil count and NLR at 24 h (respectively, p = 0.020 and p < 0.001) and at 48 h (p = 0.018 and p < 0.001) compared to patients with normal SUA levels.ConclusionsElevated serum uric acid is associated with higher short- and long-term mortality and with a greater inflammatory response after reperfusion in patients with STEMI treated with primary PCI.  相似文献   
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We studied X-chromosome inactivation patterns in blood cells from normal females in three age groups: neonates (umbilical cord blood), 25–32 years old (young women group) and >75 years old (elderly women). Using PCR, the differential allele methylation status was evaluated on active and inactive X chromosomes at the human androgen receptor (HUMARA) and phosphoglycerate kinase (PGK) loci. A cleavage ratio (CR)  3.0 was adopted as a cut-off to discriminate between balanced and unbalanced X-chromosome inactivation. In adult women this analysis was also performed on hair bulbs. The frequency of skewed X-inactivation in polymorphonuclear (PMN) cells increased with age: CR  3.0 was found in 3/36 cord blood samples, 5/30 young women and 14/31 elderly women. Mathematical analysis of patterns found in neonates indicated that X-chromosome inactivation probably occurs when the total number of haemopoietic stem cell precursors is 14–16. The inactivation patterns found in T lymphocytes were significantly related to those observed in PMNs in both young ( P  < 0.001) and elderly women ( P  < 0.01). However, the use of T lymphocytes as a control tissue for distinguishing between skewed inactivation and clonal proliferation proved to be reliable in young females, but not in elderly women, where overestimation of the frequency of clonal myelopoiesis may appear.  相似文献   
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