射野孔径形状控制器对直肠癌快速容积旋转调强放射治疗计划质量、机器传输能力和准确性的影响研究

目的:研究Eclipse15.5治疗计划系统中射野孔径形状控制器(ASC)对直肠癌快速(RapidArc)容积旋转调强放射治疗(VMAT)计划质量、机器传输能力和剂量传输准确性的影响。方法:选取医院收治的20例直肠癌患者,对每个病例生成ASC"off"、ASC"verylow"、ASC"moderate"和ASC"veryhigh"共4组RapidArc对照计划。其中ASC调节等级分别设置为关闭(off)、非常低(verylow)、中等(moderate)和非常高(veryhigh),其他计划参数设置保持一致,使用射野剂量系统(PD)验证剂量传输的准确性。主要评价指标包括剂量体积直方图(DVH)、Paddick适形指数(PCI)、梯度指数(GI)、均质性指数(HI)、剂量率(DoseRate)、机架转速(GantrySpeed)、机器跳数(MUs)、每角度机器跳数(MU/deg)和Gamma通过率,采用单因素方差分析和Kruskal-Wallis秩和检验检测4组ASC计划之间各项统计指标的差异。结果:4组ASC计划间除计划靶区平均剂量(PTV D_med)差异有统计学意义(F=3.243,P=0.027)外,其他DVH、PCI、GI和HI指标差异均无统计学意义。机器传输能力中ASC为very low、moderate和very high的MUs较off分别下降14.4%、20.9%和29.6%。4组计划间DoseRate、MU/deg和MUs差异有统计学意义(x²=16.621,x²=16.007,x²=15.877;P=0.001)。剂量传输准确性中4组计划间3%/3 mm和2%/2 mm的Gamma通过率差异均无统计学意义。结论:计划设计过程中需考虑ASC对各项计划指标的影响,应根据计划的复杂性和临床需要调整ASC的等级。     

Protein regulator of cytokinesis 1 overexpression predicts biochemical recurrence in men with prostate cancer

BackgroundProtein regulator of cytokinesis 1 (PRC1) has been reported to be implicated into the completion of cytokinesis and is dys-regulated in a cancer-specific manner. However, it roles in human prostate cancer (PCa) remain unclear. In the current study, we aimed to investigate the expression pattern of PRC1 and its clinical significance in this malignancy.Materials and methodsPRC1 protein expression in human PCa and non-cancerous prostate tissues was detected by immunohistochemistry, which was validated by microarray-based Taylor data at mRNA level. Then, the associations of PRC1 expression with clinicopathological features and clinical outcome of PCa patients were statistically analyzed.ResultsPRC1 expression in PCa tissues, at both mRNA and protein levels, were significantly higher than those in non-cancerous prostate tissues. In addition, the PCa patients with PRC1 overexpression more frequently had high Gleason score, advanced pathological stage, positive metastasis, short overall survival time and positive PSA failure than those with low Gleason score, early pathological stage, negative metastasis, long overall survival time and negative PSA failure (all P < 0.05). Moreover, PRC1 expression was identified as an unfavorable prognostic factor of biochemical recurrence-free survival in PCa patients (P < 0.001).ConclusionThese findings suggest that the aberrant expression of PRC1 may predict biochemical recurrence in men with PCa highlighting its potential as a prognostic marker of this malignancy.     

基于美国国家癌症研究所监测、流行病学、结果数据库食管癌病人预后影响因素分析

目的剖析影响食管癌病人生存的临床参数,构建列线图以预测食管癌病人的 1年、 3年及 5年生存率。方法利用美国国家癌症研究所监测、流行病学、结果数据库( National Cancer Institute,The Surveillance Epidemiology and End Results program,SEER),共获 2010年 1月至 2015年 12月 8 863例食管癌病人的年龄、病理等临床资料和相关随访数据。按随机数字表法分为验证组( 2 656例)和列线图建模组( 6 207例)(分配比例是 3∶7)。建模组用 Kaplan-Meier进行单因素生存分析,用 log-rank检验法评估生存率的差异;将在单因素分析中差异有统计学意义的变量纳入多因素 Cox比例风险模型,寻找建模组病人预后独立影响因素,将确定因素纳入并构建列线图,预测食管癌病人 1年、 3年及 5年生存率。通过一致性指数( C-index)和校正曲线评估其预测的准确性和判别能力。结果食管癌病人的年龄、性别、种族、组织分级、美国癌症联合协会( AJCC)第 7版 T分期、 N分期、 M分期、手术、化疗均是其预后独立影响因素( P<0.05)将以上因素纳入并构建列线图。 C-index:建模组内部验证为 0.726(95%CI:0.718~0.734),验证组外部验证为 0.723(95%CI:0.71,1~0.735);同时两组的校正曲线一致性良好。结论分析     

Flash放射治疗技术研究进展北大核心CSCD

Flash放射治疗(Flash-RT)具有独特的放射生物学特性及潜在临床优势,已成为放射治疗领域的研究热点,但目前关于Flash-RT原理及临床转化等研究仍处于初步阶段。本文对Flash-RT相关研究进展进行综述。     

基于蒙特卡罗模拟的小动物质子CT最优射束能量

目的 观察基于蒙特卡罗模拟的小动物质子CT （PCT）的最优射束能量。方法 采用蒙特卡罗模拟建立PCT系统,分别以不同能量质子束对体模1、2进行扫描,并以滤波反投影法重建图像,观察其中不同材料质子的相对阻止本领（RSP）值、重建误差、空间分辨率、信号噪声比（SNR）及对比噪声比（CNR）,评估图像质量,筛选最优质子射束能量。结果 重建图像中,特氟龙、聚丙烯及骨骼等效材料的RSP的相对误差均随质子能量增高而先降后升,于质子能量为130 MeV时最小,分别为0.76%、0.08%及0.05%。体模1内4种插件的SNR和CNR均随质子能量增高而降低。重建图基本无法分辨体模2内直径0.2 mm铝插件,质子能量较低时可分辨直径0.4 mm铝插件;不同质子能量下均可分辨直径0.8 mm铝插件,且空间分辨率随质子能量增高而提升,质子能量大于130 MeV后变化趋缓。结论 以蒙特卡罗模拟的小动物PCT平台的最优成像质子射束能量为130 MeV。     

The oxidative stress response of myclobutanil and cyproconazole on Tetrahymena thermophila

Using Tetrahymena thermophila as experimental models, the oxidative stress of triazole fungicides myclobutanil (MYC) and cyproconazole (CYP) was investigated. Results showed that 24-h EC₅₀ values for MYC and CYP were 16.67 (13.37–19.65) and 20.44 (18.85–21.96) mg/L, respectively; 48-h EC₅₀ values for MYC and CYP were 14.31 (13.13–15.42) and 18.76 (17.09–20.31) mg/L, respectively. Reactive oxygen species was significantly induced and cytotoxicity was caused by MYC and CYP by increasing propidium iodide (PI) fluorescence. Damage of regular wrinkles and appearing of small holes on the cell surface were observed by SEM. Furthermore, MYC and CYP also caused notable changes in enzyme activities and mRNA levels. Overall, the present study points out that MYC and CYP lead to oxidative stress on T. thermophila. The information presented in this study will provide insights into the mechanism of triazoles-induced oxidative stress on T. thermophila.     

Enhanced protection against Q fever in BALB/c mice elicited by immunization of chloroform-methanol residue of Coxiella burnetii via intratracheal inoculation

Human Q fever is recognized as a worldwide public health problem. It often occurs by inhalation of airborne aerosols contaminated with Coxiella burnetii, a gram-negative intracellular bacterium, mainly from domestic livestock. In this study, we analyzed the possibility to establish mucosal and systemic immunity against C. burnetii infection using a pulmonary delivery of chloroform-methanol residue of C. burnetii (CMR) vaccine. Mice were immunized by the intratracheal inoculation of CMR (IT-CMR) or the subcutaneous injection of CMR (SC-CMR), and the immunized mice were challenged with C. burnetii by the intratracheal route. The levels of IFN-γ, IL-12p70, IL-5, and IL-4 in the IT-CMR group in splenic T cells stimulated ex vivo were significantly higher than in the SC-CMR group. Significantly elevated sIgA to C. burnetii was detected in the bronchoalveolar lavage fluid of mice immunized by IT-CMR but not by SC-CMR, which might have contributed to the significant reduction in C. burnetii load and pathological lesions in the lungs of the mice after the challenge of C. burnetii. These results suggest that compared with SC-CMR in mice, IT-CMR was more efficient to elicit cellular and lung mucosal immune responses against aerosol infection of C. burnetii.