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31.
Intramyocardial dissecting hematoma is an uncommon complication of myocardial infarction potentially leading to cardiac rupture. The aim of the present study was to investigate coronary reperfusion results, left ventricular (LV) function recovery and remodeling and clinical outcomes in patients with anterior STEMI complicated by intramyocardial hematoma. We prospectively studied 87 patients (mean age 59?±?10 years; 88% male) with anterior STEMI (42 with intramyocardial hematoma) in order to evaluate coronary reperfusion results, LV remodeling (≥15% increase in end-systolic volume) and clinical outcomes (cardiac death, non-fatal reinfarction, and hospitalization for congestive heart failure) at 24 months. Thrombolysis in myocardial infarction (TIMI) flow score and myocardial blush grade (MBG) were assessed both pre- and post-percutaneous coronary intervention (PCI) and speckle-tracking echocardiography was performed post PCI and at 6-month follow-up. Patients with hematoma had lower post-PCI TIMI score and MBG, higher heart rate, worse LV ejection fraction and longitudinal or rotational function than their counterparts. LV remodeling occurred in 33 (78.6%) patients with hematoma and 11 (24.4%) patients without (p?<?0.001). Independent predictors of LV remodeling were heart rate (p?=?0.018), MBG (p?=?0.036) and presence of hematoma (p?<?0.001). Hematoma (log-rank test, χ2?=?9.849; p?=?0.002) and LV remodeling (log-rank test, χ2?=?13.770; p?<?0.001) were associated to a higher rate of adverse events. Cox analysis identified LV remodeling as the only independent predictor of adverse events (hazard ratio?=?3.912; 95% confidence interval, 1.429–10.714; p?=?0.008). Intramyocardial dissecting hematoma complicating anterior STEMI is an independent determinant of LV remodeling and is associated to poor prognosis.  相似文献   
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The long-term changes of liver stiffness (LS) in patients who achieve viral clearance after direct-acting anti-HCV therapy remain undefined. We conducted a multicentre prospective study to investigate this aspect. Patients with HCV infection treated with DAAs were enrolled from six Italian centres; they underwent clinical, biochemical, ultrasound and transient elastography evaluations before treatment (T0), 12 weeks (SVR12) and 24 months (T24) after the end of therapy. Among the 516 consecutive patients enrolled, 301 had cirrhosis. LS significantly decreased from T0 to SVR (14.3 vs 11.1 kPa, p = .002), with a progressive reduction until T24 (8.7 kPa, p < .001). However, only patients with steatosis and those who developed HCC did not experience a late improvement in LS. Multivariate analysis of baseline and follow-up variables identified steatosis as the only independent predictor of failure of LS improvement (OR 1.802, p = .013). ROC curve analysis of the association of LS with the risk of developing HCC showed that SVR12 ≥14.0 kPa had the highest accuracy (sensitivity 82%, specificity 99%; AUC: 0.774). Multivariate analysis revealed that LS was the only variable independently associated with an increased risk of developing HCC (OR 6.470, p = .035). Achieving an SVR was associated with a progressive, long-term decline of LS, suggesting a late improvement in liver fibrosis, besides the resolution of inflammation. Fatty liver and the development of HCC interfered with late reduction of LS. Patients with an LS ≥14 kPa at 12 weeks after the end of treatment were at higher risk for developing HCC.  相似文献   
34.
Upregulation of the sympathetic nervous system plays a key role in the pathogenesis of insulin resistance. Although the heart is a target organ of insulin, few studies have examined the mechanisms by which beta-adrenergic stimulation affects insulin sensitivity in cardiac muscle. In this study, we explored the molecular mechanisms involved in the regulation of the cross-talk between beta adrenergic and insulin receptors in neonatal rat cardiomyocytes and in transgenic mice with cardiac overexpression of a constitutively active mutant of Akt (E40K Tg). The results of this study show that beta-adrenergic receptor stimulation has a biphasic effect on insulin-stimulated glucose uptake. Short-term stimulation induces an additive effect on insulin-induced glucose uptake, and this effect is mediated by phosphorylation of Akt in threonine 308 through PKA/Ca2+-dependent and PI3K-independent pathway, whereas insulin-evoked threonine phosphorylation of Akt is exclusively PI3K-dependent. On the other hand, long-term stimulation of beta-adrenergic receptors inhibits both insulin-stimulated glucose uptake and insulin-induced autophosphorylation of the insulin receptor, and at the same time promotes threonine phosphorylation of the insulin receptor. This is mediated by serine 473 phosphorylation of Akt through PKA/Ca2+ and PI3K-dependent pathways. Under basal conditions, E40K Tg mice show increased levels of threonine phosphorylation of the beta subunit of the insulin receptor and blunted tyrosine autophosphorylation of the beta-subunit of the insulin receptor after insulin stimulation. These results indicate that, in cardiomyocytes, beta-adrenergic receptor stimulation impairs insulin signaling transduction machinery through an Akt-dependent pathway, suggesting that Akt is critically involved in the regulation of insulin sensitivity.  相似文献   
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No consistently effective therapy is yet available for the treatment of chronic HBsAg, anti-HBe, HBV-DNA-positive hepatitis. A multicenter trial has shown that the response rates are not significantly different when patients with anti-HBe-positive hepatitis are treated with six-month course of thymosin-1 or of interferon-. However, since among these patients, interferon's real efficacy is still debated, with sustained biochemical response achieved in only a few of the treated patients, we conducted this controlled study to investigate the safety and efficacy of thymosin-1 as compared with no treatment. Forty-four chronic hepatitis B virus (HBV) carriers, who were anti-HBe- and HBV-DNA-positive, were randomized, with stratification for the presence of cirrhosis at baseline liver biopsy, to receive either thymosin-1 at a dose of 900 g/m2 twice a week for six months or no treatment. At entry, both groups of patients were comparable for sex, age, liver histology, ALT, IgM anti-HBc, and HBV-DNA levels. Forty-two patients were followed-up for 20 months (median; range 12–32 months) after completion of therapy: one dropped out, and one developed hepatocellular carcinoma at six months. Thymosin-1 treatment had no side effects. Six months after the end of the therapy, HBV-DNA was negative and ALT had normalized in 14% of treated cases and in 4.5% of control group, while IgM anti-HBc was negative (<0.200) in 14% of the treated patients and in 4.5% of the controls. Among the treated patients, the median ALT levels stayed significantly lower compared to the pretreatment values during the treatment period and six months of follow-up. During the first year, there were six flares of hepatitis in the control group and five among the treated patients (P = NS), yielding a per year average of 0.3 and 0.23 flares per patient, respectively. Among the treated patients, median IgM anti-HBc levels were low with respect to baseline values 4–10 months after treatment started. None became HBsAg negative. In conclusion, these results indicate that, in anti-HBe, HBV-DNA-positive chronic hepatitis B, thymosin-1 therapy alone does not increase the response rate, but may contribute to reduce the immune-mediated liver cell necrosis as indirectly assessed by ALT and IgM anti-HBc levels.  相似文献   
37.
BACKGROUND AND AIM OF THE STUDY: Clinical and echocardiographic results were investigated to evaluate mitral valve repair in patients undergoing coronary artery bypass grafting (CABG) for ischemic cardiomyopathy (ICM) with moderately severe mitral regurgitation (MR). METHODS: A total of 78 patients (21 women, 57 men; mean age 69.5 +/- 7.8 years) with ischemic mitral regurgitation underwent mitral valve repair and CABG. The mean left ventricular ejection fraction (LVEF) was 42.4 +/- 12.4%. Among the patients, 19 (24.4%) had preoperative congestive heart failure (CHF). This surgery constituted a second such operation in five patients (6.4%). The MR was grade 3+ in 28 patients (35.9%) and 4+ in 50 (64.1%). The mean number of grafts was 3.6 per patient. RESULTS: Hospital mortality was 11.5% (n = 9). Risk factors for early mortality were preoperative NYHA class > or = III (p = 0.014), preoperative heart failure (p <0.001) and reoperation (p = 0.002). The five-year survival was 82.6 +/- 5.9%, and freedom from grade > or =2+ MR was 93.1 +/- 4.1%. Postoperatively, 66 patients (89.6%) were in NYHA class I and seven (9.4%) in class II, demonstrating a statistically significant improvement (p = 0.03). Late echocardiography showed a significant improvement in LVEF (from 42.4 +/- 12.4% to 51.7 +/- 10.9%; p = 0.01) and a reduction in pulmonary artery pressure (from 37.6 +/- 11.9 mmHg to 29.3 +/- 7.4 mmHg; p = 0.004). CONCLUSION: It is concluded that in patients with ICM, mitral valve repair combined with CABG provides a dramatic improvement in ejection fraction and in CHF, with excellent long-term survival, even in patients with a low LVEF.  相似文献   
38.
Copper-zinc superoxide dismutase-1 (SOD1) is the second most common mutated gene in amyotrophic lateral sclerosis (ALS). To date more than 150 missense mutations of SOD1 have been reported. The objective of this study was to describe a novel SOD1 mutation and its phenotypic expression. We describe a 74-year-old Caucasian man who began to complain of progressive weakness and atrophy of the right hand and over 10 months developed a severe tetraparesis, with atrophies of upper and lower limbs and neck muscles, dysphagia, and dyspnea that led to percutaneous endoscopic gastrostomy and tracheotomy. A diagnosis of ALS was made. Genetic analysis identified a heterozygous mutation in exon 4 of SOD1 that results in the amino acid substitution from arginine to cysteine at position 115 (p.R115C). We identified a novel pathogenic SOD1 mutation in a patient with a very rapid disease progression and aggressive phenotype providing additional information on the wide range of SOD1 mutations in apparently sporadic ALS and confirming the possibility of a strong genotype-phenotype correlation for distinct SOD1 mutations.  相似文献   
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Various intact and post‐injury bone phenotypes are heritable traits. In this study, we sought to determine if intramembranous bone regeneration following marrow ablation differed among common inbred mouse strains and to identify how early the differences appear. We found a ~four‐fold difference in the regenerated bone volume 21 days after marrow ablation in females from four inbred mouse strains: FVB/N (15.7 ± 8.1%, mean and standard deviation), C3H/He (15.5 ± 4.2%), C57BL/6 (12.2 ± 5.2%), and BALB/c (4.0 ± 4.4%); with BALB/c different from FVB/N (p = 0.007) and C3H/He (p = 0.002). A second experiment showed that FVB/N compared to BALB/c mice had more regenerated bone 7 and 14 days after ablation (p < 0.001), while at 21 days FVB/N mice had a greater fraction of mineralizing surface (p = 0.008) without a difference in mineral apposition rate. Thus, differences among strains are evident early during intramembranous bone regeneration following marrow ablation and appear to be associated with differences in osteogenic cell recruitment, but not osteoblast activity. The amount of regenerating bone was not correlated with other heritable traits such as the intact bone phenotype or soft tissue wound healing, suggesting that there may be independent genetic pathways for these traits. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1374–1381, 2015.  相似文献   
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