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BackgroundThe goal of this study was to characterize contemporary performance benchmarks and risk factors associated with negative appendectomy (NA) in children with suspected appendicitis.MethodsA multicenter retrospective cohort analysis of children undergoing appendectomy for suspected appendicitis was performed using data from the 2016–2021 NSQIP-Pediatric Appendectomy Targeted Public Use Files. Multivariable regression was used to evaluate the influence of year, age, sex, and WBC count on NA rate, and to generate rate estimates for NA based on different combinations of demographic characteristics and WBC profiles.Results100,322 patients were included from 140 hospitals. The overall NA rate was 2.4%, and rates decreased significantly during the study period (2016: 3.1% vs. 2021: 2.3%, p < 0.001). In adjusted analyses, the highest risk for NA was associated with a normal WBC (<9000/mm3; OR 5.31 [95% CI: 4.87–5.80]), followed by female sex (OR 1.55 [95% CI: 1.42–1.68]) and age <5 years (OR 1.64 [95% CI 1.39, 1.94]). Model-estimated risk for NA varied significantly across demographic and WBC strata, with a 14.4-fold range in rates between subgroups with the lowest and highest predicted risk (males 13–17 years with elevated WBC [1.1%] vs. females 3–4 years with normal WBC [15.8%]).ConclusionsContemporary NA rates have decreased over time, however NA risk remains high in children without a leukocytosis, particularly for girls and children <5 years of age. These data provide contemporary performance benchmarks for NA in children with suspected appendicitis and identify high-risk populations where further efforts to mitigate NA risk should be targeted.Level of EvidenceIII.  相似文献   
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BackgroundConsiderable progress has been made in therapeutic options for multiple myeloma (MM). Understanding the current landscape of MM treatment options and associated outcomes in the real world is important in providing key insights into clinical and knowledge gaps which could be targeted for further optimization.MethodsThe Canadian Myeloma Research Group Database (CMRG-DB) is a prospectively maintained disease-specific database with >7000 patients. The objective of this study was to describe the trends in the treatment landscape and outcomes including early mortality, time to next treatment, and overall survival (OS) in each line of treatment stratified by autologous stem cell transplant (ASCT) receipt among newly-diagnosed MM patients in Canada between 2007 and 2018.ResultsA total of 5154 patients were identified among which 3030 patients (58.8%) received an upfront ASCT and 2124 (41.2%) did not. At diagnosis, the median age was 64 years and 58.6% were males. Bortezomib and lenalidomide were most frequently used (>50%) in first and second-line treatment respectively among both the ASCT and non-ASCT cohort. The median OS was 122.0 months (95% Cl 115.0-135.0 months) and 54.3 months (95% CI 50.8-58.8 months) for the ASCT and non-ASCT cohort respectively with an incremental decrease in OS in each subsequent line of treatment.ConclusionWe present the largest study to date in the Canadian landscape showing the characteristics, therapy usage, and outcomes among MM patients. This information will be critical in benchmarking current outcomes and provide key insight into areas of unmet needs and gaps for improvement of MM patients nationally.  相似文献   
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目的:研究血清和尿液中外泌体miRNAs的表达水平对肾细胞癌(RCC)的诊断价值。方法:选择本院2018年11月至2020年08月诊治的68例RCC患者(RCC组)进行前瞻性分析,并将RCC患者根据临床分期进行分组,以本院同期收治的60例肾脏良性病变患者作为对照组。检测患者血清和尿液中外泌体miRNAs相对表达量,分析血清和尿液中外泌体miRNAs在肾细胞癌中的诊断价值。结果:RCC组患者血清、尿液中miR-210、miR-21、miR-153、miR-1233和miR-221表达量均明显高于对照组,miR-34a表达量均明显低于对照组(P<0.05);血清中ROC曲线显示AUC最大的为miR-221,其诊断敏感度为79.40%,特异度为95.00%;尿液中最大的为miR-34a,其敏感度为85.30%,特异度为88.30%;不同临床分期RCC患者的血清miR-210、miR-153表达量以及尿液miR-153表达量无显著差异(P>0.05),但血清和尿液中的miR-21、miR-34a、miR-1233、miR-221表达量以及尿液miR-210表达量在不同分期RCC患者中存在显著差异(P<0.05);血清中,miR-210、miR-153与临床分期无相关性(P>0.05),miR-21、miR-1233、miR-221与临床分期呈正相关,miR-34a与临床分期呈负相关(P<0.05);尿液中,miR-210、miR-153与临床分期无相关性(P>0.05),miR-21、miR-1233、miR-221与临床分期呈正相关,miR-34a与临床分期呈负相关(P<0.05)。结论:RCC患者血清、尿液外泌体miR-210、miR-21、miR-34a、miR-153、miR-1233和miR-221表达量较良性肾脏病变患者存在显著差异,同时miR-21、miR-34a、miR-1233、miR-221表达量均与RCC患者病理分期存在显著相关性,可为疾病进展评估提供参考。  相似文献   
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《Immunity》2022,55(4):623-638.e5
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BackgroundGlioblastoma (GBM) is a high-grade, poor prognosis tumor that is resistant to standard treatment. The presence of a small number of glioma stem cells (GSCs) surviving in the harsh microenvironment is responsible for their refractoriness. This study aimed to investigate the effect of a hypoxic environment on the sensitivity of GSCs to photodynamic therapy with 5-aminolevulinic acid (ALA-PDT).Materials and methodsSix human GSC lines, Mesenchymal types HGG13, HGG30, HGG1123, and Proneural types HGG146, HGG157, HGG528, were divided into two groups: normoxia (O2 21%)-cultured cells (Normoxia-GSCs), and hypoxia (O2 5%)-cultured cells (Hypoxia-GSCs). To compare the effects of different oxygen partial pressures on photoporphyrin Ⅸ (PpⅨ) biosynthetic activity, PpⅨ biosynthetic enzyme and transporter expression levels were examined by qRT-PCR; the intracellular PpⅨ concentration was determined using flow cytometry. Additionally, the sensitivity of these two groups of cells to ALA-PDT was evaluated in vitro.ResultsHypoxia-GSCs showed higher mRNA levels of FECH (ferrochelatase), which is required for iron synthesis to convert PpⅨ to heme, compared with Normoxia-GSCs. Flow cytometry revealed that the accumulation of PpⅨ in Hypoxia-GSCs reduced upon incubation with ALA. However, Hypoxia-GSCs showed less reduction in sensitivity to ALA-PDT than Normoxia-GSCs.ConclusionHypoxia-GSCs had lower intracellular PpⅨ accumulation than Normoxia-GSCs due to increased gene expression of FECH, and that their sensitivity to ALA-PDT was reduced less, despite accumulating lower concentrations of PpⅨ. ALA-PDT is a potentially effective therapy for hypoxia-tolerant GSCs that exist in hypoxia at 5% oxygen concentration.  相似文献   
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