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71.
Konstantinos Toutouzas Georgios Benetos Vasilis Voudris Maria Drakopoulou Konstantinos Stathogiannis George Latsios Andreas Synetos Alexios Antonopoulos Elias Kosmas Ioannis Iakovou Georgios Katsimagklis Antonios Mastrokostopoulos Sotiris Moraitis Vicki Zeniou Haim Danenberg Manolis Vavuranakis Dimitris Tousoulis 《JACC: Cardiovascular Interventions》2019,12(8):767-777
Objectives
The aim of this study was to compare the implantation of a self-expanding valve with or without balloon aortic valvuloplasty (BAV) in an open-label, noninferiority, randomized trial.Background
There are no randomized studies comparing the implantation of a self-expanding valve with (pre-BAV) or without BAV.Methods
Consecutive patients with severe aortic stenosis were randomly assigned to undergo transcatheter aortic valve replacement with the use of self-expanding prostheses with (pre-BAV) or without (no-BAV) pre-dilatation. The primary endpoint was device success according to the Valve Academic Research Consortium 2 criteria. Secondary endpoints included periprocedural mortality and stroke, new permanent pacemaker implantation, vascular complications, and 1-year mortality. The trial was scheduled to show noninferiority (Δ = 15%) of the direct versus the pre-BAV approach.Results
A total of 171 patients were randomized at 4 centers. Of these, 86 underwent transcatheter aortic valve replacement with pre-dilatation and 85 without. Device success was noninferior in the no-BAV group compared with the pre-BAV group (65 of 85 [76.5%] for no-BAV vs. 64 of 86 [74.4%] for pre-BAV; mean difference 2.1%; 90% confidence interval: ?8.9% to 13%). In the no-BAV group, 25 patients (29.4%) underwent post-balloon dilatation, and in the pre-BAV group, 13 patients (15.1%) underwent post-balloon dilatation (p = 0.03). Regarding major vascular complications and permanent pacemaker implantation, there was no difference between the 2 groups (log-rank p = 0.49, log-rank p = 0.54). In 1-month completed follow-up for all patients, there was 1 periprocedural stroke (0.5%), without any deaths.Conclusions
Direct, without balloon pre-dilatation, transcatheter aortic valve replacement with a self-expanding prosthesis system is noninferior to the pre-dilatation procedure. Lower post-dilatation rates were encountered in the group with pre-dilatation. (The Predilatation in Transcatheter Aortic Valve Implantation Trial [DIRECT]; NCT02448927) 相似文献72.
This study describes the frequency and the type of anemia seen in patients with nonimmune chronic idiopathic neutropenia of adults (NI-CINA). We found that NI-CINA patients had low hemoglobin levels and increased serum concentrations of erythropoietin (EPO), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1beta (IL-1beta). The hemoglobin levels correlated positively with the number of circulating neutrophils and inversely with the levels of EPO and TNF-alpha but not of IL-1beta. Anemia, defined as the reduction of the hemoglobin below 12.0 g/dl for women and 13.3 g/dl for men, was found in 23 out of 148 patients studied, a proportion of 15.5%. Two of the anemic patients had iron deficiency anemia (8.7%), 11 had anemia of chronic disease (ACD; 47.8%) presenting with normal or slightly reduced erythrocytic indices, low serum iron, and increased serum ferritin, and the remaining ten had anemia of undefined pathogenesis (AUP; 43.5%) with normal or slightly decreased erythrocytic indices, serum iron ranging from 43 to 88 microg/dl, and ferritin values ranging from 12 to 50 ng/ml. We conclude that ACD is the more frequent type of anemia seen in patients with NI-CINA, and that pro-inflammatory cytokines, notably TNF-alpha, may be involved in the pathogenesis of both ACD and AUP, given that serum levels of the cytokine were significantly increased and that the EPO response to anemia was blunted in these patients. These findings further support our previously reported suggestion for the possible existence, in NI-CINA patients, of an unrecognized low-grade chronic inflammatory process that may be involved in the pathogenesis of the disorder. 相似文献
73.
Malaria-specific transgenic CD4(+) T cells protect immunodeficient mice from lethal infection and demonstrate requirement for a protective threshold of antibody production for parasite clearance 总被引:6,自引:0,他引:6
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Stephens R Albano FR Quin S Pascal BJ Harrison V Stockinger B Kioussis D Weltzien HU Langhorne J 《Blood》2005,106(5):1676-1684
T cells are important in the immune response to malaria, both for their cytokines and their help for antibody production. To look at the relative importance of these roles, a T-cell receptor (TCR) transgenic mouse has been generated carrying a TCR specific for an epitope of the merozoite surface protein 1 (MSP-1) of the malaria parasite, Plasmodium chabaudi. In adoptive transfer experiments, malaria-specific CD4(+) T cells expand and produce interferon gamma (IFN-gamma) early in infection, but the population contracts quickly despite prolonged persistence of the parasite. MSP-1-specific CD4(+) cells can protect immunodeficient mice from lethal infection; however, the parasite is only completely cleared in the presence of B cells showing that T helper cells are critical. Levels of malaria-specific antibody and the speed of their production clearly correlate with the time of resolution of infection, indicating that a critical threshold of antibody production is required for parasite clearance. Furthermore, T cells specific for a shed portion of MSP-1 are able to provide help for antibody to the protective region, which remains bound to the infected erythrocyte, suggesting that MSP-1 has all of the components necessary for a good vaccine. 相似文献
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