Analysis of displacement damage effects on the charge-coupled device induced by neutrons at Back-n in the China Spallation Neutron Source

Displacement damage effects on the charge-coupled device(CCD)induced by neutrons at the back-streaming white neutron source(Back-n)in the China Spallation Neutron Source(CSNS)are analyzed according to an online irradiation experiment.The hot pixels,random telegraph signal(RTS),mean dark signal,dark current and dark signal non-uniformity(DSNU)induced by Back-n are presented.The dark current is calculated according to the mean dark signal at various integration times.The single-particle displacement damage and transient response are also observed based on the online measurement data.The trends of hot pixels,mean dark signal,DSNU and RTS degradation are related to the integration time and irradiation fluence.The mean dark signal,dark current and DSNU2 are nearly linear with neutron irradiation fluence when nearly all the pixels do not reach saturation.In addition,the mechanisms of the displacement damage effects on the CCD are demonstrated by combining the experimental results and technology computer-aided design(TCAD)simulation.Radiation-induced traps in the space charge region of the CCD will act as generation/recombination centers of electron-hole pairs,leading to an increase in the dark signal.

内镜窄带成像技术在复发鼻咽癌诊断中的应用

目的:探索窄带成像(NBI)内镜在复发鼻咽癌诊断中的应用价值。方法:选取疑似鼻咽癌治疗后复发的患者68例,使用具有NBI模式的纤维内镜检查鼻咽部,完善鼻咽部活检,以病理结果作为诊断的金标准,并与白光模式下检查结果比较,评估灵敏度、特异度、符合率以及不同分期阳性率结果的差异。结果:68例患者中确诊鼻咽癌54例,NBI模式灵敏度为96.30%、特异度为92.86%、符合率为95.59%、约登指数0.8916;白光模式灵敏度为83.33%、特异度为64.29%、符合率为79.41%、约登指数0.4762。NBI灵敏度、特异度、符合率均高于白光模式(P<0.05)。NBI模式早期阳性率高于白光模式(P<0.05)。结论:NBI内镜技术可以显著提高复发鼻咽癌的早期诊断,建议将其作为鼻咽癌治疗后内镜随访的常规检查。

八珍汤辅助化疗治疗老年晚期非小细胞肺癌的临床效果

目的探讨八珍汤辅助化疗治疗老年晚期非小细胞肺癌(NSCLC)的临床效果。方法选取我院收治的70例老年晚期NSCLC患者作为研究对象,将其随机分为观察组(35例,化疗+八珍汤)和对照组(35例,化疗)。比较两组的临床疗效、中医症状积分、毒副反应。结果两组的疾病控制率无明显差异(P>0.05)。治疗后,观察组的各项中医症状积分均降低,且咳嗽、乏力、食欲不振、失眠积分均低于对照组(P<0.05)。观察组Ⅰ~Ⅱ级毒副反应发生率均低于对照组(P<0.05)。结论对老年晚期NSCLC患者给予八珍汤辅助化疗治疗,可缓解临床症状,减轻化疗的毒副反应。

结直肠癌干细胞和肿瘤微环境的相互影响及靶向策略

肠癌干细胞是结直肠癌中少量的具有恶性表型特征的未分化致瘤细胞,具有自我更新和分化克隆等独特的特征,被认为是肿瘤复发、耐药、转移的主要原因。肠癌干细胞与肿瘤微环境中各成分之间互相依存,互相影响,了解肿瘤微环境中肿瘤干细胞和其他成分之间的联系,可能对结直肠癌的治疗具有重要作用。本文就肠癌干细胞和肿瘤微环境的关系及靶向治疗进行综述。

Antibacterial activity of the ethyl acetate part of Abrus cantoniensis against Staphylococcus aureus

Objective:The aim of this work was to measure the antibacterial activity(against Escherichia coli and Staphylococcus aureus[S.aureus])of the ethyl acetate part of Abrus cantoniensis and assess their potential as medicines.Methods:The experiment was divided into four groups:negative control group[with Mueller-Hinton broth(MHB)],positive control group(with 75%ethanol),blank group(with MHB)and test group(with the ethyl acetate part of Abrus cantoniensis).The antibacterial activities of the extracts were evaluated by the Oxford cup assay and minimum inhibitory concentration(MIC).Time-kill curve experiments,scanning electron microscopy,the content of DNA,RNA and protein were used to study the antibacterial mechanism of the ethyl acetate extract part on the growth and viability of S.aureus.The study procedures were approved by the Animal Care and Use Committee of Xi’an Jiaotong University(approval No.XJTULAC2016-412)on January 22,2016.Results:The ethyl acetate part of Abrus cantoniensis extract exhibited the highest inhibitory activity against the growth of S.aureus with an inhibition zone diameter of 16.4mm and MIC value of 0.5mg/mL.The general activity range of the ethyl acetate part,determined using a time-killing curve,was found to be 0.5mg/mL to 40mg/mL(MIC to 80
MIC).Changes in the scanning electron microscopy images and of DNA,RNA and proteins of S.aureus indicated possible mechanisms of the inhibitory activity of the ethyl acetate part.Conclusion:The ethyl acetate part of Abrus cantoniensis damaged bacterial cell structures,which results in protoplasm leakage,and eventually bacterial cell death.

安罗替尼治疗晚期非小细胞肺癌的疗效及安全性

目的评价安罗替尼用于晚期非小细胞肺癌(NSCLC)的疗效及安全性。方法回顾性分析经二线及以上治疗失败的晚期NSCLC患者40例,根据治疗方式不同分为安罗替尼组和对照组,每组20例。安罗替尼组每日口服安罗替尼12 mg,用药2周后停药1周,21 d为1个周期,直至疾病进展或出现无法耐受的不良反应。对照组接受最佳支持治疗。比较2组的疾病控制率(DCR)、无进展生存期(PFS)和总生存期(OS),记录患者不良反应发生情况,并评估多个临床特征与预后的关系。结果安罗替尼组部分缓解3例,疾病稳定11例,疾病进展6例,DCR优于对照组(70%vs.30%,P<0.05)。安罗替尼组中位PFS为2.8个月、中位OS为4.4个月,优于对照组的1.2个月和2个月(P<0.05)。性别、年龄、病理类型、分期、肝及脑转移等与预后无明显相关(P>0.05)。安罗替尼组不良反应包括手足综合征、乏力、纳差、咯血等,予以药物减量后症状可缓解。结论应用安罗替尼作为二线及以上治疗晚期NSCLC有较好的疗效,不良反应可耐受。

乳腺癌组织中Livin和Smac的表达及其临床意义

目的:探讨Livin和Smac蛋白在乳腺癌组织和癌旁组织中的表达及其临床意义。方法:收集乳腺癌患者43例,采用免疫组织化学S-P法检测Livin及Smac在乳腺癌组织、癌旁组织中的表达情况,应用“检验、K-M法分析临床特征及生存情况。结果:Livin在乳腺癌组织中的阳性表达率为79.1%,癌旁组织中表达率为48.8%,差异有统计学意义(P<0.05);Smac在乳腺癌组织中的阳性表达率为74.4%,癌旁组织中表达率为93.0%,差异也有统计学意义(P<0.05)。Livin和Smac蛋白的表达均与乳腺癌的TNM分期及淋巴结转移情况相关,其差异有统计学意义(两组P<0.05),并且乳腺癌组织中Livin与Smac的表达情况呈负相关(P<0.05)。此外,Livin阴性组与阳性组中5年无病生存率分别为66.7%和23.5%,Livin阴性组比阳性组无病生存期有所延长(P<0.05),而Smac阴性组与阳性组的无病生存期差异无统计学意义(P>0.05)。结论:Livin,Smac在乳腺癌中的表达水平呈负相关,提示可能有某种机制在调节这两者的表达。另外丄ivin阴性组患者的5年无病生存期有所延长,提示该蛋白或可作为乳腺癌患者的预后指标,值得进一步研究。

Single-domain antibodies for radio nuclear imaging and therapy of esophageal squamous cell carcinoma:a narrative review

Single-domain antibodies have the characteristics of small molecular weight,strong tissue penetration,and high affinity,and are widely used to construct molecular probes for disease diagnosis and treatment.This article reviews molecular imaging studies including positron emission tomography(PET),single-photon emission computed tomography/computed tomography(CT),PET/CT,and fluorescent imaging of molecular probes composed of single-domain antibodies against eight esophageal squamous cell carcinoma biological targets.These 8 targets are highly expressed on the membrane of esophageal squamous cell carcinoma cells and include epidermal growth factor receptor,human epidermal growth factor receptor 2,human epidermal growth factor receptor 3,hepatocyte growth factor receptor,vascular endothelial growth factor receptor 2,chemokine receptor 4,chemokine receptor 7,and carcinoembryonic antigen.The current problems and solutions are also discussed to provide a reference for future design of molecular imaging probes targeting esophageal squamous cell carcinoma.

The antimicrobial peptide Brevinin-2ISb enhances the innate immune response against methicillinresistant Staphylococcus aureus by activating DAF-2/DAF-16 signaling in Caenorhabditis elegans,as determined by in vivo imaging

Objective::In order to study the important role and molecular mechanism of Brevinin-2 family antimicrobial peptide Brevinin-2ISb in methicillin-resistant Staphylococcus aureus(MRSA)infection of Caenorhabditis(C.)elegans,and to find the optimal therapeutic concentration of Brevinin-2ISb.Methods::By using a C.elegans model and MRSA infection modelto study the therapeutic effect of different concentrations of Brevinin-2ISb on C.elegans.Real-time PCR was used for investigating the effect of Brevinin-2ISb on the downstream gene expression of DAF-2/DAF-16 innate immune pathway and the major virulence factor gene expression of MRSA.With protein activity tests to study the inhibitory effect of Brevinin-2ISb on MRSA virulence factor protein activity.Finally,laser confocal imaging was carried out to observe real-time expression and distribution of downstream antimicrobial proteins to further prove the effect of Brevinin-2ISb on the activation of DAF-2/DAF-16 pathway by in vivo imaging.All animal study procedures were approved by the Academic Committee at Xidian University and Xi’an Jiaotong University Animal Care and Use Committee,China(approval No.JGC201207)on July 15,2017.Results::Host immunity was largely enhanced by Brevinin-2ISb,and the expression of staphylococcal enterotoxin genes,as well as virulence factors,was suppressed by Brevinin-2ISb.Indeed,the expression of many C.elegans innate immune genes,including lys-7,spp-1,K05D8.5 and C29F3.7,was induced by Brevinin-2ISb.In particular,robust,sustained expression of the antibacterial gene lys-7 was observed after Brevinin-2ISb treatment,resulting in increased protein levels.These effects correlated with a reduction in the MRSA-mediated death of the C.elegans host.Low concentrations of Brevinin-2ISb exhibited very low hemolytic activity,and may play a positive role in host innate immunity.Specifically,activation of the DAF-2/DAF-16 pathway appears to be essential for immune activation in C.elegans treated with Brevinin-2ISb.Based on the evolutionary conservation of innate immune pathways,our results suggest that Brevinin-2ISb not only has strong antibacterial activity,but may also enhance the innate immune response in humans.This study demonstrates that Brevinin-2ISb-related peptides are potential candidates for the development of novel anti-inflammatory or anti-microbial drugs.Conclusion::Antimicrobial peptide Brevinin-2ISb effectively inhibits MRSA at low concentration.This antimicrobial peptide can prolong the life of MRSA-infected C.elegans,has very low hemolytic activity and inhibits the activity and expression of various MRSA virulence factors.More importantly,Brevinin-2ISb activated the expression of antimicrobial genes downstream of DAF-2/DAF-16,which enhanced the MRSA resistance of C.elegans.This peptide could be used as the basis for developing new drugs to replace antibiotics.