超声引导下肝细胞癌穿刺组织中Ezrin表达的临床意义

探讨Ezrin表达及超声引导下穿刺活检对肝细胞癌（HCC）的应用价值,实验方法如下：36例经超声引导下穿刺所得的HCC组织作肝穿癌组;45例手术切除的HCC组织作手术癌组,同时取12个癌旁肝组织作癌旁组;用免疫组化方法检测两组标本的Ezrin蛋白表达,并与临床病理学参数做统计学分析。得出结果：肝穿癌组Ezrin阳性表达...     

A label-free amperometric immunosensor based on horseradish peroxidase functionalized carbon nanotubes and bilayer gold nanoparticles

In this work, a novel label-free amperometric immunosensor has been constructed for detecting α-1-fetoprotein (AFP) based on nanocomposite of horseradish peroxidase (HRP) labeled carbon nanotubes (CNTs). First, the gold nanoparticles (AuNPs) were electrodeposited on the surface of the glass carbon electrode by electrochemical reduction of gold chloride tetrahydrate (HAuCl₄) to immobilize horseradish peroxidase labeled carbon nanotubes (HRP-CNTs). Then HRP-CNTs bioconjugate was immobilized on the surface of the electrodeposited AuNPs layer by the combination of forces (coordination and electrostatic force). Subsequently, it was immersed into gold colloidal nanoparticles (GNPs) solution, which was used to immobilize antibody biomolecules (anti-AFP). Enhanced sensitivity was obtained by using bioconjugates featuring HRP labeled (HRP-CNTs), which had lager specific surface area and good electronic catalysis (current response signal) compared to carbon nanotubes. Under optimized conditions, the linear ranges were from 0.2 to 200 ng mL⁻¹ with a detection limit of 0.067 ng mL⁻¹ (at an S/N of 3). The proposed immunosenor showed good precision, acceptable stability and reproducibility and could be used for the detection AFP in normal human serum, which provided a potential alternative tool for the detection of protein in clinical diagnosis.     

TMT-HCC: A tool for text mining the biomedical literature for hepatocellular carcinoma (HCC) biomarkers identification

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality worldwide. New insights into the pathogenesis of this lethal disease are urgently needed. Chromosomal copy number alterations (CNAs) can lead to activation of oncogenes and inactivation of tumor suppressors in human cancers. Thus, identification of cancer-specific CNAs will not only provide new insight into understanding the molecular basis of tumor genesis but also facilitate the identification of HCC biomarkers using CNA.     

提高水平连铸结晶器使用寿命的实践

从水平连铸工艺、冷却水水质、锥度、铜套性能及装配质量等方面分析了水平连铸结晶器使用寿命的影响因素,提出了提高水平连铸结晶器使用寿命的有效措施.     

基于质谱多反应监测技术（MRM）的蛋白质定量策略及其在肝癌生物标志物研究中的应用

肝癌是一种严重危害人类健康的恶性肿瘤,在中国占癌症死亡率的第二位,年死亡率约为20.37/10万^[1]。肝癌的早期发现是提高疗效延长患者生存时间的关键。寻找和研究特异性强、灵敏度高的肝癌生物标志物蛋白质作为肝癌的早期诊断或预警对于改善肝癌早期诊断率低的状况尤为重要。近几年来,基于质谱技术的蛋白质组学发展加快了生物标志物的研究进程^[2]。采用差异蛋白质组技术,通过比较健康和疾病状况下的蛋白质表达量变化,能获得大量与肝癌发生、发展相关的生物标志物候选蛋白质。然而,从这些候选蛋白质列表中,筛选与疾病发生发展更为密切的生物标志物,确证其在临床检测中的特异性和灵敏度却成为目前生物标志物研究流程中的瓶颈^[3]。传统的生物标志物确证的主要方法是基于免疫学原理的Western-blot和ELISA,由于特异性抗体获取困难制备周期长,使大量生物标志物候选蛋白质确证工作受到限制^[4]。而发展基于质谱MRM技术的蛋白质生物标志物候选蛋白质的定量验证策略,不需要进行特异性抗体的合成,为解决验证工作的瓶颈提供了一种新思路^[5]。 Vitronectin蛋白和clusterin蛋白在各种恶性肿瘤的发生、发展中起到重要作用,并且也有研究报道认为这两种蛋白质在血清中的表达水平与肝功能受损密切相关。在本研究中,通过采用18O稳定同位素标记方法合成肽段内标并结合MRM质谱检测技术,建立了一种方便快捷的蛋白质绝对定量方法并用于以上两种生物标志物候选蛋白质在肝癌血清中的定量确证。首先针对血清样品干扰组分多和动态范围宽的特点,优化质谱MRM检测条件,引入丙酮沉淀技术改善样品预处理步骤,设计优化的液相色谱分离条件,最终满足了多个血清样本的高通量测定要求。然后,考察了定量方法的可靠性,包括特异性、精密度、准确度、预处理回收率、测定重复性以及定量线性。方法学验证结果显示,在0.4~40 fmol•µL^－1的浓度变化范围内定量测定线性相关性良好,r2值大于0.99。蛋白质最低定量限为0.4 fmol•µL^－1。精密度RSD＜11.96%,准确度RE%＜20%。预处理回收率大于87%,测定重复性RSD＜6.87%。最后,采用建立的方法进行了20例临床血清样本的检测,其中10例健康血清,10例肝癌血清。两组定量数据的统计分析采用非参数统计方法Mann-Whitney检验。在血清样品中测定的vitronectin 和clusterin浓度变化区间分别为 48.28~265.45 mg•L^－1和49.41~136.93 mg•L^－1。统计结果显示两种蛋白质在肝癌组血清样品中浓度呈下调变化（p＝0.049;p＝0.002）,为进一步开展大样本的临床验证提供了基础。     

Significant Roles of Regulatory T Cells and Myeloid Derived Suppressor Cells in Hepatitis B Virus Persistent Infection and Hepatitis B Virus-Related HCCs

The adaptive immune system, including type1 helper T cells (Th1 cells), cytotoxic T lymphocytes (CTLs), and dendritic cells (DCs), plays an important role in the control of hepatitis B virus (HBV). On the other hand, regulatory T cells (Tregs) and myeloid derived suppressor cells (MDSCs) suppress the immune reaction in HBV and hepatocellular carcinoma (HCC). Excessive activation of immune suppressive cells could contribute to the persistent infection of HBV and the progression of HCC. The frequency and/or function of Tregs could affect the natural course in chronic hepatitis B patients and the treatment response. In addition to the suppressive function of MDSCs, MDSCs could affect the induction and function of Tregs. Therefore, we should understand in detail the mechanism by which Tregs and MDSCs are induced to control HBV persistent infection and HBV-related HCC. Immune suppressive cells, including Tregs and MDSCs, contribute to the difficulty in inducing an effective immune response for HBV persistent infection and HBV-related HCC. In this review, we focus on the Tregs and MDSCs that could be potential targets for immune therapy of chronic hepatitis B and HBV-related HCC.     

静磁场和交流电耦合作用下超薄板坯水平连铸的凝固组织

研究在电磁振荡作用下,金属超薄板坯水平连铸的凝固组织及其与电流强度的关系。结果显示,在静磁场和交流电正交所产生的电磁振荡力的作用下,水平连铸纯Sn超薄板坯的凝固组织明显细化,且细化效果随所施电流的增大而增强;而对Sn-10%Pb合金超薄板坯,则显著地促进其等轴晶组织的形成,使其中心层面出现等轴晶区,该等轴晶层的厚度随电流强度增大而增加。实验结果表明,电磁振荡作用有利于抑制柱状晶对穿、中心疏松、夹杂和/或气体聚集、以及偏析等超薄板坯水平连铸中常见的凝固缺陷。     

Modulation of the antioxidant/pro-oxidant balance,cytotoxicity and antiviral actions of grape seed extracts

Grape seed extracts (GSEs) were investigated in yeast cells harbouring defects in their antioxidant system (regarding the cellular growth and growth recovery from H₂O₂ insult). GSEs antioxidant activity was detected in wild-type and mutant strains Δcta1, Δgsh1 and Δoye2glr1, while pro-oxidant activity in Δsod1 cells was seen. Assessment of proliferation of prostate cancer PC3 and HBV-replicating HepG2 2.2.15 cells treated with GSEs has shown higher cytotoxicity of red grape seed extract (RW) than white grape seed extract (WW) subjective to dose and period of administration. No antiviral effect was detected by measuring the secreted virion particles in HepG2 2.2.15 cells treated with GSEs. The GSEs play a dual antioxidant/pro-oxidant role in vivo according with the cellular antioxidant system deficiencies and exhibit cytotoxic properties in PC3 and HepG2 2.2.15 cell lines, but no antiviral action against HBV.     

水平连铸结晶器动态热流分布的实验研究

采用在结晶器壁内埋置热电偶的方法,对水平连铸结晶器在连铸时的动态热流密度分布进行了测试。经过对测试结果数据处理,得出了热流密度分布表达式和结晶器壁的温度场。     

超声引导下肝癌穿刺组织中DEK表达的临床意义

为探讨超声引导下穿刺活检肝癌组织中DEK表达的临床意义,作者利用36例经超声引导下穿刺所得的肝癌组织经免疫组化方法检测DEK蛋白的表达,得出结果：肝穿癌组织DEK阳性表达率为52.8%（17/36）,明显高于癌旁正常肝组织（阳性率为0%,0/8）（p=0.007）,与肿块大小密切相关（p=0.040）。结果表明,DEK与肝癌的发生发展有一定关系,超声引导下肝肿物穿刺活检并检测肿瘤组织中相关基因的表达对肝癌治疗有一定的指导价值。