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991.
Comparison of long‐term outcome in anthracycline‐related versus idiopathic dilated cardiomyopathy: a single centre experience
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Alessandra Fornaro Iacopo Olivotto Luigi Rigacci Mauro Ciaccheri Benedetta Tomberli Cecilia Ferrantini Raffaele Coppini Francesca Girolami Francesco Mazzarotto Marco Chiostri Massimo Milli Niccolò Marchionni Gabriele Castelli 《European journal of heart failure》2018,20(5):898-906
Aims
Cardiac dysfunction is a severe complication of anthracycline‐containing anticancer therapy. The outcome of anthracycline‐induced cardiomyopathy (AICM) compared with other non‐ischaemic causes of heart failure (HF), such as idiopathic dilated cardiomyopathy (IDCM), is unresolved. The aim of this study was to compare the survival of AICM patients with an IDCM cohort followed at our centre from 1990 to 2016.Methods and results
We included 67 patients (67% female, 50 ± 15 years) with AICM, defined as onset of otherwise unexplained left ventricular ejection fraction (LVEF) ≤50% following anthracycline therapy, and 488 IDCM patients (28% female, 55 ± 12 years). Patients were followed with constantly optimized HF therapy, for 7.6 ± 5.5 and 8.1 ± 5.5 years, respectively. In both cohorts, 25% of patients reached the combined endpoint of death/heart transplantation. Overall survival rates at 5 and 10 years were similar (AICM: 86% and 61%, IDCM: 88% and 75%; P = 0.61), and so was cardiovascular survival (AICM: 91% and 76%, IDCM: 91% and 80%; P = 0.373), also after 1:1 propensity matching (P = 0.27) and adjusting for age, LVEF and left ventricular size. A trend toward higher all‐cause mortality was present in AICM patients [hazard ratio (HR) 1.67, 95% confidence interval (CI) 0.95–2.92, P = 0.076]. No differences were observed between AICM and IDCM with regard to pharmacological HF therapy, but AICM patients were less likely to receive devices (13% vs. 41.8% in IDCM, P < 0.001).Conclusion
Cardiovascular mortality in patients with AICM did not differ from that of a matched IDCM cohort, despite cancer‐related morbidity and less prevalent use of devices. These data suggest that patients with AICM should be treated with appropriate guideline‐directed medical therapies similar to other non‐ischaemic dilated cardiomyopathies.992.
Th2 cells are less susceptible than Th1 cells to the suppressive activity of CD25+ regulatory thymocytes because of their responsiveness to different cytokines 总被引:11,自引:1,他引:11
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Cosmi L Liotta F Angeli R Mazzinghi B Santarlasci V Manetti R Lasagni L Vanini V Romagnani P Maggi E Annunziato F Romagnani S 《Blood》2004,103(8):3117-3121
T-cell clones generated from both CD4+CD25+ and CD8+CD25+ human thymocytes were assessed for their ability to suppress the proliferative response to allogeneic stimulation of type 1 T-helper (Th1) or type 2 T-helper (Th2) clones derived from autologous CD4+CD25- thymocytes. Both CD4+ and CD8+ T-regulatory (Treg) cells completely suppressed the proliferation of Th1 clones but exhibited significantly lower suppressive activity on the proliferation of Th2 clones. The partial suppressive effect on Th2 cells was further reduced by the addition in culture of interleukin-4 (IL-4), whereas it was increased in the presence of an anti-IL-4 monoclonal antibody (mAb). The suppressive activity on Th2 clones was also completely inhibited by the addition of IL-7, IL-9, and IL-15 but not of IL-2, whereas the suppressive effect on Th1 clones was only reverted by the addition of IL-15. Of note, Th2 clones expressed significantly higher amounts of mRNA for IL-4 receptor (IL-4R) and IL-9R alpha chains than Th1 clones, whereas the expression of mRNA for IL-2R, IL-7R, and IL-15R alpha chains was comparable. Taken together, these findings demonstrate that Th2 cells have a lower susceptibility than Th1 cells to the suppressive activity of human CD25+ regulatory thymocytes, because they are able to produce, and to respond to, growth factors distinct from IL-2, such as IL-4 and IL-9. 相似文献
993.
Human CD34(+) blood cells induce T-cell unresponsiveness to specific alloantigens only under costimulatory blockade 总被引:5,自引:0,他引:5
Arpinati M Terragna C Chirumbolo G Rizzi S Urbini B Re F Tura S Baccarani M Rondelli D 《Experimental hematology》2003,31(1):31-38
OBJECTIVES: The immunogenic role of human CD34(+) cells in allogeneic hematopoietic stem cell transplantation is controversial. In this study we tested the role of CD40 and CTLA4 ligands on CD34(+) cell costimulation of HLA-mismatched lymphocytes. MATERIALS AND METHODS: An anti-CD40L monoclonal antibody (hu5C8) and/or CTLA4-Ig molecule were used in primary mixed lymphocyte culture (MLC) with irradiated CD34(+) blood cells and allogeneic responders. Then, secondary MLC, cytotoxic activity, and effector cytokine expression and production were measured. RESULTS: Each reagent was able to reduce anti-CD34(+) cell alloreactivity, but only the combination of the anti-CD40L monoclonal antibody and CTLA4-Ig induced greater than 90% inhibition of T-cell response in primary MLC and prevented generation of cytotoxic T cells when priming with purified CD34(+) cells. Importantly, responder cells activated by allogeneic CD34(+) cells in the presence of anti-CD40L monoclonal antibody and CTLA4-Ig entered a state of antigen-specific unresponsiveness while responding to third party antigen, tetanus toxoid, or phytohemagglutinin, and showed suppression of interferon-gamma and increase of interleukin-10 expression and release. Interestingly, addition of interleukin-2 in secondary MLC did not reverse T-cell anergy. CONCLUSIONS: The results demonstrate that human CD34(+) blood progenitors stimulate T-cell responses potently and can induce T-cell unresponsiveness only when both B7:CD28 and CD40:CD40L pathways are blocked, with an increase of interleukin-10-producing cells. Therefore, our data allow design of in vivo studies aimed at achieving T-cell tolerance across HLA barriers by using purified CD34(+) cells and costimulatory blockade. 相似文献
994.
Bifunctional role for VEGF-induced heme oxygenase-1 in vivo: induction of angiogenesis and inhibition of leukocytic infiltration 总被引:9,自引:0,他引:9
Heme-oxygenases (HOs) catalyze the conversion of heme into carbon monoxide and biliverdin. HO-1 is induced during hypoxia, ischemia/reperfusion, and inflammation, providing cytoprotection and inhibiting leukocyte migration to inflammatory sites. Although in vitro studies have suggested an additional role for HO-1 in angiogenesis, the relevance of this in vivo remains unknown. We investigated the involvement of HO-1 in angiogenesis in vitro and in vivo. Vascular endothelial growth factor (VEGF) induced prolonged HO-1 expression and activity in human endothelial cells and HO-1 inhibition abrogated VEGF-driven angiogenesis. Two murine models of angiogenesis were used: (1) angiogenesis initiated by addition of VEGF to Matrigel and (2) a lipopolysaccharide (LPS)-induced model of inflammatory angiogenesis in which angiogenesis is secondary to leukocyte invasion. Pharmacologic inhibition of HO-1 induced marked leukocytic infiltration that enhanced VEGF-induced angiogenesis. However, in the presence of an anti-CD18 monoclonal antibody (mAb) to block leukocyte migration, VEGF-induced angiogenesis was significantly inhibited by HO-1 antagonists. Furthermore, in the LPS-induced model of inflammatory angiogenesis, induction of HO-1 with cobalt protoporphyrin significantly inhibited leukocyte invasion into LPS-conditioned Matrigel and thus prevented the subsequent angiogenesis. We therefore propose that during chronic inflammation HO-1 has 2 roles: first, an anti-inflammatory action inhibiting leukocyte infiltration; and second, promotion of VEGF-driven noninflammatory angiogenesis that facilitates tissue repair. 相似文献
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998.
Bizzarri R Cerbai B Signori F Solaro R Bergamini E Tamburini I Chiellini E 《Biogerontology》2003,4(6):353-363
A procedure is described for the preparation of (S)-dolichol and (S)- nor dolichol starting from the polyprenyl fraction extracted from Gingko biloba integer or exhausted leaves. The procedure appears extremely valuable in obtaining the two chiral isoprenoid compounds in good chemical yields and retention of a high degree of enantiomeric excess. Also, the (S)- nor dolichol represents a good chiral precursor for the preparation of (14)C-labelled (S)-dolichol to be used in biological investigations into the (S)-dolichol catabolism in the functional living cell. Furthermore, the possible role of (S)-dolichol as a free radical scavenger in the cell membrane was preliminarily evaluated by means of a (1)H-NMR analytical method. Apparently, experimental results substantiate this hypothesis. 相似文献
999.
Metra M Nodari S Parrinello G Bordonali T Bugatti S Danesi R Fontanella B Lombardi C Milani P Verzura G Cotter G Dittrich H Massie BM Dei Cas L 《European journal of heart failure》2008,10(2):188-195
BACKGROUND: Renal function is a powerful prognostic variable in patients with heart failure (HF). Hospitalisations for acute HF (AHF) may be associated with further worsening of renal function (WRF). METHODS AND RESULTS: We analysed the clinical significance of WRF in 318 consecutive patients admitted at our institute for AHF. WRF was defined as the occurrence, at any time during the hospitalisation, of both a > or =25% and a > or =0.3 mg/dL increase in serum creatinine (s-Cr) from admission (WRF-Abs-%). RESULTS: Patients were followed for 480+/-363 days. Fifty-three patients (17%) died and 132 (41%) were rehospitalised for HF. WRF-Abs-% occurred in 107 (34%) patients. At multivariable survival analysis, WRF-Abs-% was an independent predictor of death or HF rehospitalisation (adjusted HR, 1.47; 95%CI, 1.13-1.81; p=0.024). The independent predictors of WRF-Abs-%, evaluated using multivariable logistic regression, were history of chronic kidney disease (p=0.002), LV ejection fraction (p=0.012), furosemide daily dose (p=0.03) and NYHA class (p=0.05) on admission. CONCLUSION: WRF is a frequent finding in patients hospitalised for AHF and is associated with a poor prognosis. Severity of HF and daily furosemide dose are the most important predictors of the occurrence of WRF. 相似文献
1000.
Neurovascular plasticity of the hippocampus one week after a single dose of ketamine in genetic rat model of depression
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Maryam Ardalan Gregers Wegener Benedetta Polsinelli Torsten M. Madsen Jens R. Nyengaard 《Hippocampus》2016,26(11):1414-1423
Glutamatergic system and the structural plasticity hypothesis are principal components for rapid and sustained antidepressant effects of novel antidepressant therapeutics. This study represents the first investigation of the structural plasticity of the hippocampus as one of the main contributed mechanisms to the sustained anti‐depressive effect of ketamine. Flinders Sensitive Line (FSL) and Flinders Resistant Line (FRL) rats were given a single intraperitoneal injection of ketamine (15 mg/kg) or saline 7 days before perfusion‐fixed. The optical fractionator method was used to estimate the total number of neurons in the granular cell layer. Microvessel length in the molecular layer of DG was evaluated with global spatial sampling method. By use of the physical disector method, the number of synapses was estimated. The volume of the hippocampus was larger in the FRL‐vehicle rats compared with FSL‐vehicle group and in FSL‐ketamine versus FSL‐vehicle rats (P < 0.05). The number of non‐perforated synapses was significantly higher in the FSL‐ketamine versus FSL‐vehicle group, (P = 0.01). A significant effect of ketamine on enhancement of the number of neurons in DG in FSL rats was observed (P = 0.01). The total length of the microvessels 1 week after ketamine treatment in the FSL rats significantly increased (P < 0.05). Our results indicate that neurovascular changes of hippocampus could be one of the possible mechanisms underlying the sustained antidepressant effect of ketamine by reversing alteration of the number of the excitatory synapses, neuronal number and length of the microvessels in the hippocampus. © 2016 Wiley Periodicals, Inc. 相似文献