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131.
First-generation drug-eluting stents (DES) have been associated with impaired localized coronary vasomotion and delayed endothelialization. We aimed to compare coronary vasomotion after implantation of a newer-generation everolimus-eluting stent (EES), with a first-generation paclitaxel-eluting stent (PES). Coronary vasomotion was studied in 19 patients with EES and 13 with PES. Vasomotor response was measured proximally and distally to the stent and in a remote vessel (reference segment). Quantitative coronary angiography was performed offline. Endothelium independent vasomotion did not differ significantly between the two groups. EES showed significant vasodilatation while PES showed vasoconstriction at both proximal (+4.5?±?3.6 vs ?4.2?±?6.9, p?<?0.001) and distal (+4.6?±?7.9 vs ?4.8?±?9.3, p?=?0.003) segments. The reference segment did not show any significant difference in vasodilatation between the two groups (+9.8?±?6.4 vs +7.2?±?5.2, p?=?0.17). Endothelium-dependent vasomotion at adjacent stent segments is relatively preserved after EES implantation while vasoconstriction was observed after PES implantation.  相似文献   
132.
We investigated the left ventricular (LV) function, using for the first time strain (S) and strain rate (SR) imaging, in long-term survivors affected by acute lymphoblastic leukemia treated with a low cumulative dose of anthracyclines, and in presence of a normal global LV systolic and diastolic function. A total of 21 were enrolled in the study. The mean cumulative dose of anthracylines was 180 mg/m2 (range: 120-210 mg/m2). As control group 21 age-sex matched healthy subjects were included. Radial S (17 ± 3% vs. 55 ± 6%, P < 0.0001) and SR (2.1 ± 0.3 vs. 3.0 ± 0.8 1\s, P < 0.0001), assessed on the midsegment of the posterior wall from the parasternal views were significantly reduced when compared with controls. Conversely, myocardial performance index was not able to discriminate between patients and controls. In this preliminary study, the myocardial deformation indices appear to be a more sensitive noninvasive technique for detecting subclinical LV dysfunction than other echocardiographic measurements.  相似文献   
133.
Cardiotrophin-1 (CT-1) is a member of the interleukin (IL-6) family of cytokines. Plasma CT-1 levels correlate with the left ventricle mass index in patients with dilatated cardiomyopathy and congestive heart failure (CHF). The aim of this paper was to evaluate CT-1 plasma levels, before and after cardiac resynchronization therapy CRT, and to characterizeits prognostic role in patients with CHF. Fifty-two consecutive patients (M/F = 39/13; 56 ± 11 years old) underwent clinical and echocardiographic evaluation, and blood sample collection at baseline. The same evaluation was repeated 6.4 ± 0.79 months after CRT. Patients with a decreased LV end-systolic volume by at least 15% (reverse remodeling) were considered echo responders to CRT. Twenty-nine patients (56%) were responders to CRT. After CRT, only 15 patients (29%) showed increased CT-1 after CRT. They were all non responders to CRT. A multivariate, logistic modelshowed CT-1 as an independent predictor of CRT echo response (p = 0.005; OR 0.97). During follow-up (18 ± 7 months), 21 cardiac events in 18 patients occurred. A Cox multivariable model showed plasma BNP pre-CRT (p = 0.02; CI 1.2–5.6; OR 3.1) and CT1 post-CRT (p = 0.01; CI 1.4–4.3; OR 2.7) as independent predictors of cardiac events. Analysis of CT-1 plasma levels deserves future consideration for larger, longitudinal studies in patients with CHF.  相似文献   
134.
The orexins A (oxA) and B are peptides discovered in the rat hypothalamus and successively found in some peripheral organs of the mammalian body. They binds two protein G-coupled receptors defined receptor 1 (ox1r) and 2 for orexins, the first of which is highly specific for oxA while the second binds both the peptides with equal affinity. This work aimed to detect the presence of oxA and ox1r in the testis of the South American camelid alpaca (Vicugna pacos) and investigate the role played by them on Leydig cell steroidogenesis. The species alpaca acquired, in the last years, increasing zootechnical interest for the quality of the wool produced and its breeding spread from the country of origin to USA, Australia and Europe. Immunohistochemistry allowed us to detect oxA in Leydig and Sertoli cells, spermatogonia, resting spermatocytes, round and oval spermatids. Ox1r-immunoreactivity was found in Leydig cells and round, oval and elongated spermatids. The expression of the two peptides in tissue extracts was established by using Western blotting technique. Such results demonstrated that in the alpaca testis exists in a cellular complex able to produce and/or internalize oxA. Finally, the effect of oxA on steroidogenesis was investigated by means of in vitro cultured thin testis slices which were added with oxA or/and Müllerian Inhibiting Substance (MIS), a steroidolitic agent basally produced by the Sertoli cell. OxA evoked increase of testosterone production while MIS a decrease. The consecutive addition of oxA and MIS, or vice versa, highlighted an antagonistic interplay between the two substances which has been thought to be the main molecular event at the basis of the oxA-stimulated steroidogenesis mechanism.  相似文献   
135.
Erratic regulation of glucose metabolism including hyperglycemia is a common condition in premature infants and is associated with increased morbidity and mortality. The objective of this study was to examine histological and ultrastructural differences in the endocrine pancreas in fetal (throughout gestation) and neonatal baboons. Twelve fetal baboons were delivered at 125 days (d) gestational age (GA), 140d GA, or 175d GA. Eight animals were delivered at term (185d GA); half were fed for 5 days. Seventy-three nondiabetic adult baboons were used for comparison. Pancreatic tissue was studied using light microscopy, confocal imaging, and electron microscopy. The fetal and neonatal endocrine pancreas islet architecture became more organized as GA advanced. The percent areas of α-β-δ-cell type were similar within each fetal and newborn GA (NS) but were higher than the adults (P<0.05) regardless of GA. The ratio of β cells within the islet (whole and core) increased with gestation (P<0.01). Neonatal baboons, which survived for 5 days (feeding), had a 2.5-fold increase in pancreas weight compared with their counterparts killed at birth (P=0.01). Endocrine cells were also found in exocrine ductal and acinar cells in 125, 140 and 175d GA fetuses. Subpopulation of tissue that coexpressed trypsin and glucagon/insulin shows the presence of cells with mixed endo-exocrine lineage in fetuses. In summary, the fetal endocrine pancreas has no prevalence of a α-β-δ-cell type with larger endocrine cell percent areas than adults. Cells with mixed endocrine/exocrine phenotype occur during fetal development. Developmental differences may play a role in glucose homeostasis during the neonatal period and may have long-term implications.  相似文献   
136.
G Ventura  G Cozzi 《Lancet》2012,380(9844):803; author reply 803-803; author reply 804
  相似文献   
137.
We assessed whether macrophage colony-stimulating factor (M-CSF) levels are associated with left ventricular systolic dysfunction (LVSD) in patients with acute myocardial infarction (AMI). We studied 56 patients with AMI (mean age: 67 ± 12 years) and identified those with clinical (Killip class >II) or echocardiographic signs (ejection fraction ≤45%) of LVSD. We evaluated the established cardiovascular risk factors and measured several cardiovascular biomarkers, including M-CSF. Serum M-CSF concentrations (pg/mL) were significantly increased in patients with both clinical and echocardiographic signs of LVSD (460 ± 265 vs 290 ± 210, P = .0103 and 493 ± 299 vs 287 ± 174, P = .0028, respectively). We found a significant inverse association between M-CSF and ejection fraction (r = -.351, P = .0079). Logistic regression analysis revealed that, among all evaluated clinical and biochemical parameters, the stronger predictor of LVSD was M-CSF (odds ratios 2.1, 95% confidence interval 1.1-2.9, P = .0168). This is the first study reporting plasma M-CSF levels as independent determinants of low LV ejection fraction and clinical LV dysfunction in patients with AMI.  相似文献   
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Human herpes virus 8 (HHV-8) or Kaposi sarcoma-associated herpes virus is the etiologic agent of Kaposi sarcoma, primary effusion lymphoma, and plasma cell-type multicentric Castleman disease (MCD). HHV-8 encodes a viral homolog of human IL-6, called viral IL-6 (vIL-6), which does not require the cellular IL-6 receptor for binding to the ubiquitously expressed gp130 receptor subunit and subsequent JAK-STAT signaling. Thus, in contrast to IL-6, vIL-6 can stimulate virtually all cells in the body. To elucidate the mechanism by which vIL-6 drives human diseases, we generated transgenic mice that constitutively express vIL-6 under control of the MHC class I promoter. The mice were found to exhibit vIL-6 serum levels comparable with those observed in HHV-8-infected patients, to contain elevated amounts of phosphorylated STAT3 in spleen and lymph nodes, where vIL-6 was produced, and to spontaneously develop key features of human plasma cell-type MCD, including splenomegaly, multifocal lymphadenopathy, hypergammaglobulinemia, and plasmacytosis. Transfer of the vIL-6 transgene onto an IL-6-deficient genetic background abrogated MCD-like phenotypes, indicating that endogenous mouse IL-6 is a crucial cofactor in the natural history of the disease. Our results in mice suggest that human IL-6 plays an important role in the pathogenesis of HHV-8-associated MCD.  相似文献   
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