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21.
目的通过检索已出版的文献,回顾有关儿童急性淋巴细胞白血病(ALL)患者接种流感疫苗有效性和安全性,探索最优的接种策略,为临床提供参考。方法按照PICOS原则制定研究主题的检索策略,检索Pub Med、Em Base等英文文献数据库,由两位研究者独立使用PRISMA流程图筛选符合标准的文献,提取研究数据并进行评价。结果共检索到文献186篇,经筛选获有效文献29篇。评价研究文献显示,多数ALL患儿接种灭活流感疫苗可产生中等强度的免疫应答,各亚型/系的血清抗体保护率可分别达到33%~85%(A/HIN1)、38%~92%(A/H3N2)、14%~92%(B)及37%~88%(pH1N1);血清阳转率可分别达到0%~65%(A/HIN1)、20%~85%(A/H3N2)、0%~92%(B)及11%~81%(pH1N1),低于健康儿童或实体肿瘤患儿。疫苗预防实验室确诊的流感或流感样病例的临床使用有效性的研究有限,研究结果有争议。接种时有较高的基线淋巴细胞计数、Ig G水平、结束化疗或低化疗强度阶段、高年龄段患儿以及给予加强剂次可能会有较强的免疫应答;减活流感疫苗、高剂量流感疫苗、含佐剂流感疫苗均不能改善ALL患儿的免疫应答。疫苗在各治疗阶段接种均有较好的耐受性,不良反应轻微。结论 ALL患儿接种流感疫苗安全性好,可产生中等强度的血清学保护作用,建议维持治疗阶段接种标准剂量灭活流感疫苗;疫苗的临床有效性还有待设计良好的临床试验验证。  相似文献   
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Genomic research in hematological malignancies has focused far more prominently on somatic mutations than on germline variants. Although increasing numbers of germline variants are being identified, a substantial proportion of familial myeloid malignancies have no causal allele pinpointed. Here we review the biological, technological, and clinical challenges that stand in the way of the goal of establishing, implementing, and interpreting a comprehensive panel of germline variants for testing. Achieving this goal would inform care for large numbers of myeloid malignancy patients. Furthermore, knowledge of germline susceptibility variants and their corresponding genes will shed light on disease processes, potentially suggesting therapeutic strategies tailored to specific variants.  相似文献   
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The interaction of CD47 and signal-regulatory protein alpha (SIRPα) induces “don't eat me signal”, leading suppression of phagocytosis. This signal can affect the clinical course of malignant disease. Although CD47 and SIRPα expression are associated with clinicopathological features in several neoplasms, the investigation for adult T-cell leukemia/lymphoma (ATLL) has not been well-documented. This study aimed to declare the association between CD47 and SIRPα expression and clinicopathological features in ATLL. We performed immunostaining on 73 biopsy samples and found that CD47 is primarily expressed in tumor cells, while SIRPα is expressed in non-neoplastic stromal cells. CD47 positive cases showed significantly higher FoxP3 (P = .0232) and lower CCR4 (P = .0214). SIRPα positive cases presented significantly better overall survival than SIRPα negative cases (P = .0132). SIRPα positive cases showed significantly HLA class I (P = .0062), HLA class II (P = .0133), microenvironment PD-L1 (miPD-L1) (P = .0032), and FoxP3 (P = .0229) positivity. In univariate analysis, SIRPα expression was significantly related to prognosis (Hazard ratio [HR] 0.470; 95% confidence interval [CI] 0.253-0.870; P = .0167], although multivariate analysis did not show SIPRα as an independent prognostic factor. The expression of SIRPα on stromal cells reflects activated immune surveillance mechanism in tumor microenvironment and induce good prognosis in ATLL. More detailed studies for gene expression or genomic abnormalities will disclose clinical and biological significance of the CD47 and SIRPα in ATLL.  相似文献   
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IntroductionB-cell malignancies confer an increased risk of infection due to associated immune defects. Conflicting evidence exists on the risk of infection in patients receiving ibrutinib. We conducted a systematic review and meta-analysis to estimate relative risk of infection with ibrutinib in B-cell malignancies.MethodsA systematic search of Embase, Medline, Web of Science, Scopus, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, European Union Clinical Trials Register, and ClinicalTrials.gov was performed through January 15, 2019, to identify randomized controlled trials comparing ibrutinib with other agents or placebo in B-cell malignancies. We pooled point estimates using the Der Simonian and Laird random-effects model. Statistical analyses were performed by Stata/SE 15.1.ResultsSeven studies randomizing 2167 patients were included in the final analysis. Treatment duration in studies ranged from 9.4 to 38.7 months. Ibrutinib was associated with a significantly increased risk of infection (any grade and grade 3-5) in patients with B-cell malignancies [pooled risk ratio (RR) = 1.34, 95% confidence interval [CI], 1.06-1.69, P = .015; and RR = 1.35, 95% CI, 1.05-1.74, P = .018, respectively]. In patients with chronic lymphocytic leukemia, a significantly increased risk of grade 3-5 infection was noted in the ibrutinib group [pooled RR = 1.24, 95% CI, 1.02-1.50, P = .028]. Incidences of pneumonia and upper respiratory tract infection were not significantly different between groups.ConclusionOur meta-analysis found that ibrutinib was associated with significantly higher risk of infections in patients with B-cell malignancies. Occurrence of major individual subtypes was not different between groups, possibly as a result of inconsistent reporting across studies.  相似文献   
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BackgroundAbnormalities of chromosome 3 in myelodysplastic syndromes (MDS), that is, inversion 3 (inv[3]), translocation 3q (t[3q]), or deletion 3q (del[3q]), are defined as poor-risk karyotypes in the Revised International Prognostic Scoring System (IPSS-R). The objective of this study was to further define the outcomes of patients with MDS with chromosome 3 abnormalities and address the impact of hypomethylating agent (HMA) therapy on this patient subset.Patients and MethodsThrough the MDS Clinical Research Consortium, we identified 411 patients with chromosome 3 abnormalities and MDS or oligoblastic acute myeloid leukemia (20%-30% blasts).ResultsSpecific chromosome 3 aberrations and cytogenetic complexity were predictive of survival; patients with t(3q) and isolated chromosome 3 had improved overall survival (OS), albeit still poor, whereas patients with complex cytogenetics, including those with 3p abnormalities, had inferior OS. Overall response rates to HMAs among this patient population were similar to those of patients with nonchromosome 3–MDS (52%, with a 25% complete remission rate), although with higher response rates in decitabine-treated patients (69% vs. 45%, P = .008). HMA therapy improved the OS of patients with higher-risk MDS compared with intensive chemotherapy (median OS of 15.5 vs. 8.2 months; P = .017). This improvement remained significant in multivariate analyses (hazard ratio, 0.60; P = .018); however, there were no chromosome 3 aberrations among this subgroup predictive of improved response rates to or survival from HMAs.ConclusionPatients with MDS with chromosome 3 abnormalities represent a cytogenetic cohort with poor OS, and there is an urgent need for novel therapeutic strategies.  相似文献   
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ABSTRACT

Natural products are still a promising source of bioactive molecules. Food and Drug Administration data showed that approximately 49% of the approved molecules originate naturally or chemically-resemble these substances, of which more than 70% are being used in anticancer therapy. It is noteworthy that at present there are no scientific studies to prove the effectiveness and safety of a number of plants used in folk medicine such as in the case of Calyptranthes grandifolia O. Berg (Myrtaceae) originally from South America. The aim of the present study was to determine the biological potential and toxicological effects of the aqueous leaf extract of C. grandifolia. The main detected phytoconstituents were condensed tannins and flavonoids and a high quantity of polyphenols. Regarding the antimicrobial potential, the extract exerted inhibitory activity against Pseudomonas aeruginosa. The results also revealed the extract induced DNA damage in a concentration-dependent manner in RAW 264.7 cells. In addition, C. grandifolia produced cytotoxicity in leukemia cell lines (HL60 and Kasumi-1) without affecting isolated human lymphocytes but significantly inhibited JAK3 and p38α enzyme activity. Taken together, these findings add important information on the biological and toxicological effects of C. grandifolia, indicating that aqueous extract may be a source of natural antimicrobial and antileukemic constituents.  相似文献   
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Recent years have seen tremendous advances in treating acute myeloid leukemia (AML), largely because of progress in understanding the genetic basis of the disease. The US Food and Drug Administration approved 7 agents for AML in the last 2 years: the first new drugs in decades. In this review, the authors discuss these new approvals in the backdrop of an overall strategy for treating AML today. Treating AML in the modern era requires: 1) access to and use of upfront genetic and cytogenetic testing, not only to describe prognosis but also to help identify the best available therapy; 2) effectively working new therapies into a conventional backbone of treatment, including transplantation; and 3) continued commitment to clinical trials designed to capitalize on advances in genetics and immunology to foster the next wave of drug approvals.  相似文献   
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BackgroundUp to 55% of non-APL acute myeloid leukemias (AML) lack a molecular target suitable for standardized disease monitoring. We aimed to evaluate the prognostic significance of WT1 gene expression at early stages of intensive treatment.Patients and MethodsA total of 106 consecutive patients with intermediate and high-risk AML who had WT1 expression at diagnosis >500 copies/104 ABL and who achieved remission after 1 to 2 cycles of induction treatment were analyzed. WT1 expression was measured in peripheral blood using a standardized European LeukemiaNet method. Overexpression was defined as >50 copies/104 ABL. The median follow-up was 30 months.ResultsPatients with normal versus high WT1 expression after 2 cycles of chemotherapy had overall survival (OS) at 3 years of 66% versus 41% (P = .01); event-free survival (EFS) 45% versus 22% (P = .01). Prognostic significance of WT1 expression after 2 cycles of treatment was maintained in the group of patients treated with chemotherapy alone without hematopoietic stem cell transplantation in first line treatment (OS 70% vs. 36%, P = .02; EFS 35% vs. 0%, P = .03). Significant prognostic factors for EFS on multivariate analysis were the achievement of molecular remission (<50 copies of WT1) at any time during treatment (hazard ratio [HR] 0.47, P = .04) and increased WT1 expression after 2 cycles of chemotherapy (HR 2.0, P = .03).ConclusionIncreased WT1 expression after 2 cycles of chemotherapy is a negative prognostic factor for survival. WT1 remains a valuable molecular marker in AML without any leukemia-specific mutation, especially if next generation sequencing and/or digital polymerase chain reaction are not routinely available.  相似文献   
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