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Plasma cell leukemia (PCL) is a rare and aggressive plasma cell disorder, with poor outcome. Bortezomib‐based regimens (BBR) are highly effective in myeloma, but there is limited information about their efficacy and safety in PCL. Thus, we retrospectively collected data from 42 consecutive PCL patients (25 with primary PCL‐pPCL and 17 with secondary PCL‐sPCL) to explore the role of BBR in this entity. BBR were administered in 29 of 42 patients, while 6 of 25 patients with pPCL underwent autologous transplantation. Objective response (≥partial response) was significantly higher in patients treated with BBR versus conventional therapies (69% vs. 30.8%, P = 0.04); 27.5% of patients treated with BBR achieved at least very good partial response (vgPR). The highest ORR was observed in pPCL patients treated with BBR (88.9%; ≥vgPR: 33.3%). In BBR‐group, grade 3 of 4 hematological, neurological and renal toxicity and neutropenic infections were observed in 41.4%, 7%, 3.4%, and 31%, respectively. With a median follow‐up of 51 months, median overall survival (OS) for patients treated with BBR versus conventional therapies was 13 versus 2 months (P < 0.007). Median OS of patients with pPCL and sPCL treated with BBR was 18 and 7 months, respectively (P < 0.001). In the multivariate analysis normal PLTs, treatment with BBR and high quality response were the only powerful predictors for survival. Our study carrying the longest reported median follow‐up, demonstrated that treatment of PCL with BBR induces high response rates and prolongs survival over conventional therapies, regardless of additional autologous transplantation rescue or established high risk features, with manageable toxicity. Am. J. Hematol. 89:145–150, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
994.
In preclinical and early phase pharmacologic trials in sickle cell disease, the percentage of sickled erythrocytes after deoxygenation, an ex vivo functional sickling assay, has been used as a measure of a patient's disease outcome. We developed a new sickle imaging flow cytometry assay (SIFCA) and investigated its application. To perform the SIFCA, peripheral blood was diluted, deoxygenated (2% oxygen) for 2 hr, fixed, and analyzed using imaging flow cytometry. We developed a software algorithm that correctly classified investigator tagged “sickled” and “normal” erythrocyte morphology with a sensitivity of 100% and a specificity of 99.1%. The percentage of sickled cells as measured by SIFCA correlated strongly with the percentage of sickle cell anemia blood in experimentally admixed samples (R = 0.98, P ≤ 0.001), negatively with fetal hemoglobin (HbF) levels (R = ?0.558, P = 0.027), negatively with pH (R = ?0.688, P = 0.026), negatively with pretreatment with the antisickling agent, Aes‐103 (5‐hydroxymethyl‐2‐furfural) (R = ?0.766, P = 0.002), and positively with the presence of long intracellular fibers as visualized by transmission electron microscopy (R = 0.799, P = 0.002). This study shows proof of principle that the automated, operator‐independent SIFCA is associated with predictable physiologic and clinical parameters and is altered by the putative antisickling agent, Aes‐103. SIFCA is a new method that may be useful in sickle cell drug development. Am. J. Hematol. 89:598–603, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
995.
Primary established genetic abnormalities in B-cell precursor acute lymphoblastic leukemia include high hyperdiploidy (51–65 chromosomes), the translocations t(12;21)(p13;q22)/ETV6-RUNX1 fusion and t(9;22)(q34;q11)/BCR-ABL1 fusion, MLL rearrangements and intrachromosomal amplification of chromosome 21. These rearrangements are of prognostic and therapeutic relevance and are usually mutually exclusive. We identified 28 patients at diagnosis with both a primary genetic rearrangement and an immunoglobulin heavy chain locus translocation using chromosomal analysis and fluorescence in situ hybridization. Among these patients, the immunoglobulin heavy chain locus translocation partner gene was identified in six (CRLF2, CEBPA, CEBPB, TRA/D@, IGF2BP1 and IGK@). Clonal architecture was investigated in 17 patients using multiple color interphase fluorescence in situ hybridization analysis, which showed that the translocation was acquired as a secondary abnormality in ten patients, in four patients the etiology was undetermined and in three patients it was observed in a separate clone from the primary chromosomal rearrangement. These findings demonstrate the co-existence of immunoglobulin heavy chain locus translocations with other primary chromosomal rearrangements either in the same or separate clones, which may have prognostic significance in B-cell precursor acute lymphoblastic leukemia. Clinical trials: UKALLXII: Study ID n. ISRCTN77346223 and ALL2003: Study ID n. ISRCTN07355119  相似文献   
996.
Steroid-refractory graft-versus-host disease is a life-threatening complication after allogeneic stem cell transplantation. Evidence is accumulating that steroid-refractory graft-versus-host disease is associated with endothelial distress. Endothelial cell homeostasis is regulated by nitric oxide, and serum nitrates are derived from nitric oxide synthase activity or dietary sources. In this retrospective study based on 417 patients allografted at our institution we investigated whether quantification of serum nitrates could predict steroid-refractory graft-versus-host disease. Elevated pre-transplant levels of serum nitrates (>26.5 μM) predicted steroid-refractory graft-versus-host disease (P=0.026) and non-relapse mortality (P=0.028), particularly in combination with high pre-transplant angiopoietin-2 levels (P=0.0007 and P=0.021, respectively). Multivariate analyses confirmed serum nitrates as independent predictors of steroid-refractory graft-versus-host disease and non-relapse mortality. Differences in serum nitrate levels did not correlate with serum levels of tumor necrosis factor or C-reactive protein or expression of inducible nitric oxide synthase in blood cells. Patients with high pre-transplant nitrate levels had significantly reduced rates of refractory graft-versus-host disease (P=0.031) when pravastatin was taken. In summary, patients at high risk of developing steroid-refractory graft-versus-host disease could be identified prior to transplantation by serum markers linked to endothelial cell function. Retrospectively, statin medication was associated with a reduced incidence of refractory graft-versus-host disease in this endothelial high-risk cohort.  相似文献   
997.
The prognostic significance of early response to treatment has not been reported in relapsed pediatric acute myeloid leukemia. In order to identify an early and easily applicable prognostic factor allowing subsequent treatment modifications, we assessed leukemic blast counts in the bone marrow by morphology on days 15 and 28 after first reinduction in 338 patients of the international Relapsed-AML2001/01 trial. Both day 15 and day 28 status was classified as good (≤20% leukemic blasts) in 77% of patients. The correlation between day 15 and 28 blast percentages was significant, but not strong (Spearman correlation coefficient = 0.49, P<0.001). Survival probability decreased in a stepwise fashion along with rising blast counts at day 28. Patients with bone marrow blast counts at this time-point of ≤5%, 6–10%, 11–20% and >20% had 4-year probabilities of survival of 52%±3% versus 36%±10% versus 21%±9% versus 14%±4%, respectively, P<0.0001; this trend was not seen for day 15 results. Multivariate analysis showed that early treatment response at day 28 had the strongest prognostic significance, superseding even time to relapse (< or ≥12 months). In conclusion, an early response to treatment, measured on day 28, is a strong and independent prognostic factor potentially useful for treatment stratification in pediatric relapsed acute myeloid leukemia. This study was registered with ISRCTN code: 94206677.  相似文献   
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Background:Good communication strategies are essential in times of crisis, such as the coronavirus pandemic. The dissemination of inaccurate information and the need for social isolation to control coronavirus disease 2019 (COVID-19) have shown a negative impact on the population, causing damage to mental health, with the appearance or worsening of symptoms of stress, fear, anxiety, and depression. Thus, the systematic review study is intended to gather evidence on the impact of information about COVID-19 on the mental health of the population.Methods:This systematic review protocol is conducted using the guidelines of the preferred reporting items for systematic reviews and meta-analyses protocols and the Cochrane Handbook for Systematic Reviews of Interventions. The review aims to include published studies that address the exposure of the general population to information about COVID-19, through observational and experimental studies, which consider the following outcomes: fear, stress, anxiety, and depression. Thus, a comprehensive research strategy will be conducted in the following databases: PubMed / Medline, Scopus, Web of Science, EMBASE, Science Direct, CINAHL, PsycINFO and Cochrane Central Register of Controlled Trials (CENTRAL). Two independent reviewers will perform all procedures, such as study selection, data collection, and methodological evaluation. Disagreements will be forwarded to a third reviewer. RevMan 5.3 software will be used for data analysis.Results:This systematic review will provide evidence of the influence of access to and consumption of media and scientific information about COVID-19 on the mental health of the population. It will consider information about the characterization of the study and the population studied, clinical and epidemiological information on mental health, and data on access to and consumption of media and scientific information.Discussion:The results should inform about the consequences of communication about the new coronavirus on the emergence or worsening of psychological and psychiatric symptoms, allowing to develop strategies to achieve effective communication of information to promote the mental health of the population.Systematic review registration number:PROSPERO CRD42020182918  相似文献   
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