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The LAM2001 phase 3 trial, involving 832 patients with acute myeloid leukemia (AML; median: 46 years) proposed HLA-identical sibling allograft HSCT for all patients with an identified donor. The trial compared reduced-intensity conditioning (RIC) for patients older than 50 years of age (N = 47) and myeloablative conditioning for younger patients (N = 117). BM HSCT was performed in the younger patients, while the older ones received a consolidation course, followed by peripheral blood allo-HSCT using RIC. The incidence of grade II-IV acute GVHD, was 51.9% (95% confidence interval [CI]: 42.1-61.8) and 11.3% (1.6-21.2) after myeloablative or RIC, respectively (P < .0001) and that of chronic GVHD 45.8% (95% CI: 34.8-56.7) and 41.7% (24.7-58.6; NS). Cumulative incidence of nonrelapse mortality at 108 months was 15.8% (95% CI: 9.8-23.2) for myeloablative, and 6.5% (0.2-16.2) for RIC (NS). CI of relapse at 108 months was 21.7% (95% CI: 13.9-28.6) and 28.6% (16.5-43.4; NS). Overall survival at 108 months was 63.4% (95% CI: 54.6-72.2) and 65.8% (52.2-72.2), respectively, after myeloablative or RIC (NS). RIC peripheral blood stem cell allo-HSCT is prospectively feasible for patients between the ages of 51 and 60 years without excess of relapse or nonrelapse mortality, and compares favorably with myeloablative marrow allo-HSCT proposed to younger patients.  相似文献   
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The chemokine receptor CXCR4 is a critical regulator of cell migration and serves as a coreceptor for HIV-1. The chemokine stromal cell derived factor-1, also known as CXCL12, binds to CXCR4 and exerts its biologic functions partly through the small guanosine triphosphate hydrolase (GTPase) Rac1 (ras-related C3 botulinum toxin substrate 1). We show in different cell types, including CD34(+) hematopoietic stem and progenitor cells, that inhibition of Rac1 causes a reversible conformational change in CXCR4, but not in the related receptors CXCR7 or CCR5. Biochemical experiments showed that Rac1 associates with CXCR4. The conformational change of CXCR4 on Rac1 inhibition blocked receptor internalization and impaired CXCL12-induced Gα(i) protein activation. Importantly, we found that the conformation adopted by CXCR4 after Rac1 inhibition prevents HIV-1 infection of both the U87-CD4-CXCR4 cell line and of primary peripheral blood mononuclear cells. In conclusion, our data show that Rac1 activity is required to maintain CXCR4 in the responsive conformation that allows receptor signaling and facilitates HIV-1 infection; this implies that Rac1 positively regulates CXCR4 function and identifies the Rac1-CXCR4 axis as a new target for preventing HIV-1 infection.  相似文献   
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Expert testimony is being used increasingly in child sexual assault cases. This study extended a prior study that examined factors related to expert testimony (evidence strength, coherence and credentials of the expert) on ratings of guilt and overall verdict. Specifically, we replicated our prior study but with two modifications: we used community samples as opposed to university students, and participants made their decisions in groups of 12 (as in the case of juries where one decision represents the overall group) rather than having participants decide and submit their verdicts and guilt ratings individually. Consistent with the prior (less ecologically valid) study, credentials of the expert had negligible impact. Evidence that was high in strength elicited a relatively high guilt rating even when the testimony was low in coherence. Further, it appears that when participants deliberate in a group (as in the case of juries) they are more conservative in their judgements (i.e., they are less likely to give a guilty verdict) compared to individual jurors who make their decisions alone. These findings suggest that caution must be exercised when drawing conclusions about the generalisability of prior research findings where participants did not engage in group deliberation.  相似文献   
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This qualitative study aims to describe the psychological impact of the diagnosis announcement of pathogenic Copy Number Variations (pCNVs). We performed semi-structured interviews of 60 parents of 41 affected children and 5 geneticists who announced the diagnoses. The diagnosis of the best characterized microdeletion syndromes, often defined by patronymic names (e.g. Williams syndrome), is generally made on a clinical basis by geneticists and confirmed by fluorescence in situ hybridization analysis. Chromosomal microarray, on the contrary, can allow the disclosure of rare pCNVs named after cytogenetic formulas, with poorly known clinical consequences: this makes doctors feel less confident with these diagnosis announcements. The disclosure of pCNVs named after cytogenetic formulas does not facilitate the parental mental representation of the disease, leading some parents to call into question the genotype-phenotype correlation or the very notion of a diagnosis. The announcement of inherited pCNVs can increase the feeling of parental guilt; the disclosure of de novo pCNVs can induce a feeling of “breakage” in the mental representation of the parent-child vertical transmission. In conclusion, our study shows that the disclosure of pCNVs has a significant psychological impact: a multidisciplinary approach to the diagnosis announcement, including a psychological support, should be systematically warranted.  相似文献   
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ObjectiveThe study aimed at evaluating in vitro the effect of caffeine on expression of cystatin SN, a potential marker of sensitivity to bitterness in humans.MethodsDifferentiation of human submandibular gland (HSG) cells was induced by culturing cells on Matrigel. Caffeine cytotoxicity was assessed over 3 days by the Resazurin test. Finally, effects of 5, 50 and 100 μM caffeine exposure on cystatin SN expression were explored over 3 days by ELISA.ResultsAt concentrations relevant to human adult plasma levels (5, 50 and 100 μM), caffeine did not affect cell viability whether cells were differentiated or not. Cystatin SN levels were overall higher in differentiated cells and increased with time in both conditions. There was a significant (p < 0.001) effect of caffeine on cystatin SN expression specifically in differentiated cells.ConclusionsThe HSG cell line proved to be a relevant tool to study in vitro the effect of caffeine at concentrations consistent with dietary intake in human subjects. The results suggest that salivary cystatin SN abundance may depend on caffeine intake, with possible consequences on taste sensitivity.  相似文献   
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