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Early response to induction chemotherapy is a predictor of outcome in acute myeloid leukemia (AML). We determined the prevalence and significance of postinduction residual disease (RD) by multidimensional flow cytometry (MDF) in children treated on Children's Oncology Group AML protocol AAML03P1. Postinduction marrow specimens at the end of induction (EOI) 1 or 2 or at the end of therapy from 249 patients were prospectively evaluated by MDF for RD, and presence of RD was correlated with disease characteristics and clinical outcome. Of the 188 patients in morphologic complete remission at EOI1, 46 (24%) had MDF-detectable disease. Those with and without RD at the EOI1 had a 3-year relapse risk of 60% and 29%, respectively (P < .001); the corresponding relapse-free survival was 30% and 65% (P < .001). Presence of RD at the EOI2 and end of therapy was similarly predictive of poor outcome. RD was detected in 28% of standard-risk patients in complete remission and was highly associated with poor relapse-free survival (P = .008). In a multivariate analysis, including cytogenetic and molecular risk factors, RD was an independent predictor of relapse (P < .001). MDF identifies patients at risk of relapse and poor outcome and can be incorporated into clinical trials for risk-based therapy allocation. This study was registered at www.clinicaltrials.gov as NCT00070174.  相似文献   
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Brown R  Kabani K  Favaloro J  Yang S  Ho PJ  Gibson J  Fromm P  Suen H  Woodland N  Nassif N  Hart D  Joshua D 《Blood》2012,120(10):2055-2063
The transfer of membrane proteins between cells during contact, known as trogocytosis, can create novel cells with a unique phenotype and altered function. We demonstrate that trogocytosis is more common in multiple myeloma (MM) than chronic lymphocytic leukemia and Waldenstrom macroglobulinaemia; that T cells are more probable to be recipients than B or natural killer cells; that trogocytosis occurs independently of either the T-cell receptor or HLA compatibility; and that after trogocytosis, T cells with acquired antigens can become novel regulators of T-cell proliferation. We screened 168 patients with MM and found that CD86 and human leukocyte antigen G (HLA-G) were antigens commonly acquired by T cells from malignant plasma cells. CD3(+)CD86(acq+) and CD3(+) HLA-G(acq+) cells were more prevalent in bone marrow than peripheral blood samples. The presence of either CD86 or HLA-G on malignant plasma cells was associated with a poor prognosis. CD38(++) side population cells expressed HLA-G, suggesting that these putative myeloma stem cells could generate immune tolerance. HLA-G(+) T cells had a regulatory potency similar to natural Tregs, thus providing another novel mechanism for MM to avoid effective immune surveillance.  相似文献   
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Takayasu's arteritis (TA) is primary vasculitis. Cardiac involvements in TA is due to the consequences of the vascular lesions as well as the primary pathology of the heart. The disease activity of TA is known to influence the prognosis of TA. We hypothesized that the cardiovascular involvement of TA is related to the disease activity. We evaluated the cardiovascular manifestations of TA, and we assessed their relation to the disease activity of TA. Two hundred four patients were diagnosed with TA from September, 1994 to March, 2009 according to the diagnostic criteria of the 1990 American College of Rheumatology. Their clinical features and the laboratory, angiographic and echocardiographic findings were retrospectively reviewed. The group with active disease activity was defined as satisfying one of the following criteria: i) an elevated ESR or CRP level, ii) thickened arterial wall with mural enhancement on CT or MR angiography, and iii) carotidynia at the time of the initial diagnosis. One hundred thirty nine patients (69.2%) were classified as the active group. The cardiovascular signs and symptoms were not generally different between the active and inactive groups. The active TA patients had more frequent involvement of the ascending aorta and the aortic arch and its main branches than did the inactive group. The active group showed a higher incidence of significant aortic valve regurgitation and pulmonary hypertension, and a higher level of NT-proBNP. These findings suggest that disease activity plays an important role for the cardiovascular manifestations of TA. The TA patients with higher activity have more cardiovascular morbidity compared to the TA patients with low disease activity.  相似文献   
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The aim of this study was to explore whether the candidate gene polymorphisms contribute to fibromyalgia susceptibility. The authors conducted a meta-analysis on associations between serotonin transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR) S/L allele, catechol-O-methltransferase (COMT) val158Met, and serotonin 2A (5-HT2A) receptor 102T/C polymorphisms and fibromyalgia susceptibility as determined using the following: (1) allele contrast, (2) recessive, (3) dominant models, and (4) contrast of homozygotes. We also performed a systematic review with available data of the candidate genes. A total of 21 separate comparisons were considered in this systematic review and meta-analysis. Seventeen candidate genes and over 35 different polymorphisms were identified in studies on fibromyalgia susceptibility. Meta-analysis of the 5-HTTLPR S/L allele and COMT val158Met failed to reveal any association with fibromyalgia. However, meta-analysis of the C allele, CC + CT genotype, and CC versus TT genotype of the 5-HT2A receptor 102T/C polymorphism showed significant association with fibromyalgia. The overall OR of the association between the C allele and fibromyalgia was 1.333 (95% CI = 1.053–1.688, P = 0.017). The ORs for the CC + CT genotype, and CC versus TT genotype showed the same pattern as that observed for the C allele (OR = 1.541, 95% CI = 1.032–2.303, P = 0.035; OR = 1.838, 95% CI = 1.151–2.936, P = 0.011). This meta-analysis demonstrates that the 5-HT2A receptor 102T/C polymorphism confers susceptibility to fibromyalgia. In contrast, no association was found between the 5-HTTLPR S/L allele, COMT val158Met, and susceptibility to fibromyalgia.  相似文献   
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