血清单糖指标作为胃癌早期诊断的潜在生物标志物

提高胃癌的早期诊断有助于降低胃癌的死亡率.胃癌的发病与遗传、生活方式以及环境影响有关.由于血清中生物糖蕴含与机体状态有关的丰富信息,本研究分析了胃癌患者与健康对照组血清单糖组成差异,发现胃癌患者血清中游离与水解甘露糖浓度显著高于健康个体.与现有消化道肿瘤标志物相结合,构建了适用于胃癌筛查的联合诊断模型.诊断模型的受试者工作特征曲线下面积(AUC=0.900 8)高于糖类抗原199(CA199)和癌胚抗原(CEA),并适用于早期胃癌的诊断.使用TCGA数据库中的胃癌RNA测序数据对甘露糖代谢相关基因进行分析,发现甘露糖焦磷酸化酶A(GMPPA)在不同恶性程度的胃癌组织中表达差异显著,GMPPA低表达的患者预后较差.本研究为胃癌的早期筛查与预后判断提供了新方法和新思路.     

尿液生物标志物

疾病的早期诊断是医学最重要的问题．早期诊断可以给医生有效治疗的机会．尿液不像血液那样受身体稳态效应的控制,能够汇集大量的疾病相关变化,因此尿液能够更好地反映早期微小的变化,是生物标志物的更好体液来源．动物模型研究证明了尿液作为早期标志物来源的潜力．部分研究利用了临床样本,但是很多研究没有认真考虑可以影响尿液的大量各种混杂因素．我们提出如果疾病引起的变化足够大、足够独特的时候,才能利用疾病对健康人群分组的方式发现疾病尿液标志物．如果能利用同一个人的前后对照,可以解决大量混杂影响因素的对照问题,让尿液标志物更早地用于临床．在没有疾病前样本的情况下,还可以利用一个病人对多个健康对照样本的方法找到疾病线索．本文将总结现代尿液生物标志物理论的发生发展和现状,并展望未来的发展前景．      

广西3种褐煤芳烃生物标志物组合特征

总结了广西三盆地３种第三系褐煤的多环芳烃特征，主要包括芳香倍半萜，二倍半萜和三萜类。其中以陆源奥利烷，乌散烷和羽扇烷前生物衍生而来的单芳于四芳三萜烃类为主，芳香二倍半萜，倍半萜次之 。     

生物除磷体系中生物标志物的管理初探

通过研究MDA、电解质渗出量和Q2^-这3个损伤性指标,初步探讨了通过生物标志物来管理生物除磷体系的可行性。结果表明,MDA、电解质渗出量和Q．^-这3个指标中,利用SOD电极在线检测Q．^-的变化来管理除磷体系最为简便。从Q．^-的变化规律得出当体系由好氧交替到厌氧时。前90min对释放磷尤为重要,即受氧胁迫时,系统产生O2．^-浓度不能高于0．025mmol／g,否则磷的释放不会增加,进而影响系统的除磷效果。因此,可以通过在线监测O2．^-的浓度变化来动态管理除磷体系。     

miRNA在恶性肿瘤诊断中的作用

miRNA(MicroRNA)是一类长度为19～25个核苷酸的单链非编码RNA,其在转录后水平调控生物体的生长发育、细胞分化、增殖和应激反应等生理生化进程.同样,miRNA在恶性肿瘤的发生发展中发挥着重要的调控作用,研究miRNA与恶性肿瘤之间的关系已经受到人们的广泛关注.本文对miRNA的生物学功能特征、其与肿瘤发生发展的关系、作为新肿瘤标志物的可能性及在肿瘤诊断中的作用进行综述,以期为恶性肿瘤的诊断提供帮助.     

基于ICP-MS的高脂血症潜在元素标志物研究

为研究高脂血症模型大鼠毛发中无机元素的含量变化,基于毛发样品筛选高脂血症疾病诊断的潜在元素标志物.采用高脂乳剂灌胃的方式建立高脂血症大鼠模型,取健康对照组与高脂血症模型组大鼠背部毛发进行微波消解,采用电感耦合等离子体质谱(ICP-MS)建立毛发无机元素表达谱,分析模型组与对照组差异.对毛发中75种无机元素的相对含量进行检测,通过主成分分析(PCA)获得得分图和载荷图,筛选差异元素,并使用SPSS统计软件对差异元素进行独立样本t检验.结果显示,对照组与模型组毛发无机元素表达谱存在一定差异,PCA得分图中两组聚类明显,具有生物学功能的差异元素有Mg、Al、Cr、Cu、Zn等,毛发中上述元素相对含量在模型组中显著升高(P<0.001).基于ICP-MS技术从毛发中发现了高脂血症的潜在元素标志物,为深入研究高脂血症疾病机制及其临床诊断提供了新的研究思路和科学依据.     

血清miR-25、miR-223和miR-373作为食管鳞癌生物标志物的评价

为了探讨血清miRNA作为诊断标志物的可行性,利用茎环引物进行qRT-PCR,检测了miR-25、miR-223和miR-373在正常人血清、食管鳞癌患者术前和术后第7 d血清、癌组织和癌旁组织的相对表达量.实验结果表明:术前食管鳞癌病人的3种血清miRNA相对表达量高于正常人和手术后第7 d病人,AUC分别为0.794、0.839和0.873,癌组织的这3种miRNA相对表达量高于癌旁组织.这3种miRNA在食管癌患者癌组织的高表达导致血清的这3种miRNA含量增高,因此这3种血清miRNA可以作为候选诊断标志物.     

生物标志物应用于骨性关节炎研究进展

骨性关节炎(Osteoarthritis,OA)是中老年常见的慢性关节疾病。其主要病变是关节软骨的退行性变和继发性骨质增生。最早期是关节软骨局部发生软化、糜烂,最后软骨下骨外露。可继发滑膜、关节囊及关节周围肌肉的改变,是综合因素所致的不可逆关节损害。如何早期诊断骨性关节炎是医学中的难题,由于疾病发展缓慢,早期往往无明显临床症状及影像学表现,故传统的诊断方法难以给予早期诊断。治疗本病的关键是如何早期诊断关节软骨损伤,国内外学者进行了大量研究,欲在OA患者的体液中寻找反映疾病变化的特异性生物标志物(BM)来及时反映关节软骨代谢状态,将对骨性关节炎的早期诊断、治疗及预后评价,起到积极的指导作用。     

水体污染风险预警的生物标志物技术

在提出生物标志物内涵的基础上,分析了污染物在水体及生物之间的迁移途径并构建了生物标志物应用系统架构图,重点阐述了生物标志物相关理论基础及生物标志物应用体系,概括性总结了生物监测技术在国内外水环境监测中的研究与应用现状,系统分析了水体污染风险预警技术的发展趋势,同时提出了生物标志物研究与应用中重点关注的几个问题.     

露空对红树蚬生物标志物的影响

【目的】研究样品露空运输过程对红树蚬(Polymesoda erosa)生物标志物的影响。【方法】野外采集的红树蚬经8℃、26℃和35℃露空处理8h,随后在26℃海水中暂养恢复3h、6h、12h和24h,测定红树蚬血液超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、乙酰胆碱酯酶(AChE)、谷胱甘肽转硫酶(GST)活性,以及铁还原力(FRAP)和丙二醛(MDA)含量。【结果】8℃和35℃露空处理,SOD、CAT、AChE、GST、FRAP和MDA均显著升高。26℃露空处理,SOD、AChE和MDA显著升高,GST显著降低,CAT和FRAP有所降低但不显著。经过暂养,红树蚬各项指标均能恢复到初始水平,但24h内波动较大。【结论】露空对红树蚬的生物标志物有显著影响。26℃露空8h后,经3~6h暂养,红树蚬生物标志物与初始水平最接近。     

Serum microRNA-155 as a potential biomarker for breast cancer screening

MicroRNAs(miRs) have been shown to be differentially expressed in the serum of cancer patients and controls,and can thus be used as biomarkers for cancer screening.We detected the expression level of miR-155 in the serum of female breast cancer patients and healthy controls to investigate whether serum miR-155 could discriminate patients with early-stage breast cancer.Serum samples were collected from 20 female patients with newly diagnosed breast cancer and 10 healthy controls.Real-time quantitative PCR was used to detect the expression level of miR-155.The expression level of miR-155 was significantly increased in the serum of breast cancer patients compared with in the serum of normal controls.MiR-155 may be useful as a blood-based biomarker for breast cancer screening.     

A microRNA polycistron as a potential human oncogene

To date, more than 200 microRNAs have been described in humans; however, the precise functions of these regulatory, non-coding RNAs remains largely obscure. One cluster of microRNAs, the mir-17-92 polycistron, is located in a region of DNA that is amplified in human B-cell lymphomas. Here we compared B-cell lymphoma samples and cell lines to normal tissues, and found that the levels of the primary or mature microRNAs derived from the mir-17-92 locus are often substantially increased in these cancers. Enforced expression of the mir-17-92 cluster acted with c-myc expression to accelerate tumour development in a mouse B-cell lymphoma model. Tumours derived from haematopoietic stem cells expressing a subset of the mir-17-92 cluster and c-myc could be distinguished by an absence of apoptosis that was otherwise prevalent in c-myc-induced lymphomas. Together, these studies indicate that non-coding RNAs, specifically microRNAs, can modulate tumour formation, and implicate the mir-17-92 cluster as a potential human oncogene.     

Regulation of microRNA on plant development and viral infection

THE FIRST MIRNA WAS IDENTIFIED IN C. ELEGANS AS EARLY AS IN 1993; THE IMPORTANCE OF MIRNAS, HOWEVER, IS RECOGNIZED ONLY RECENTLY AFTER THE DISCOVERY OF MIRNAS EXISTING UNIVERSALLY IN EUKARYOTIC ORGANISMS. THE SECOND MIRNA WAS IDENTIFIED IN 2000[1]. SINCE …     

A comparative study of n -alkane biomarker and pollen records: an example from southern China

We report the results of a comparative study of n-alkane biomarkers and pollens in lacustrine and peat deposits at Dingnan, Jiangxi Province in southern China, and discuss the likely causes for the discrepancy in the interpretations of the n-alkane biomarker and pollen records in terms of climate and vegetation change. The results show that past changes in climate and vegetation revealed by the n-alkane record are not always consistent with the pollen assemblage record in the whole section. Biomarkers do not permit direct identification of the plant family and/or genus and mainly record compositions of local plant remains, while pollens mainly reflect the regional vegetation change. Biomarkers and pollen records complement each other, providing a better picture of local and regional environments. Furthermore, biomarkers are more sensitive than pollen to climatic and vegetational change. Several climatic events are clearly identified by the n-alkane biomarker proxies, such as C₃₁/(C₂₇+C₂₉+C ₃₁) ratio and can be correlated to the North Atlantic Heinrich event, B/A, YD and two dry-cool events during the early Holocene such as the periods of 9850 to 9585 cal a B.P. and 8590 to 7920 cal a B.P. These events are consistent with those found in the surrounding regions, suggesting that the regional climate was coupled with global-scale abrupt climatic events. Our results suggest that biomarker and pollen data can record the more detailed climate and vegetation information, thus improving the resolution and precision of vegetation and climate reconstruction. Supported by National Natural Science Foundation of China (Grant No. 40602004) and National Basic Research Program of China (Grant No. 2004CB720200)     

Using the biomarker bonded on the asphaltenes for biodegraded oil-source correlation

Ruthenium-ion-catalyzed oxidation(RICO)has been used to investigate asphaltenes from three oils with the same origin in the Juquan Basin and three oils with the same origin but with different degree of biodegradation in the Turpan Basin,Northwest China.The preliminary results showed that the biomarkers bonded on the asphaltenes with the same origin is similar and is correlated with the free biomarker in saturates.The bonded biomarkers have no relationship with the biodegradation.An application on the severely biodegraded oils is reported here.The biomarker and benznecarboxylic methyl esters reflecting t eh structure of the asphaltenes after RICO should provide a new way for oil-source correlation and it should be specially useful for severely biodegraded oil-source correlation.     

抗结核分枝杆菌感染的免疫机制

对宿主利用体内各种细胞与结核分支杆菌的相互作用进行了综述.机体抵抗结核分枝杆菌感染的机制包括特异性免疫和非特异性免疫,参与非特异性免疫的主要有巨噬细胞和γδT细胞,另外,树突状细胞在引发T细胞免疫方面起着关键的作用.由于结核分支杆菌是胞内寄生菌,特异性免疫以细胞免疫为主,主要包括CD4+T细胞免疫和CD8+T细胞免疫.     

老年肺结核病患者的生活方式调查及护理干预

目的通过对老年肺结核病患者的生活方式的护理干预,改善患者的健康状态,提高治疗效果。方法采用问卷表对老年肺结核病患者的生活方式进行调查,对不利于健康的生活方式进行护理干预。结果干预组息者的康复进程明显优于对照组。结论护理干预能改善患者的生活方式,加速康复和提高生活质量。     

三维位势问题新的规则化边界元法

本文致力于三维位势问题的间接变量规则化边界元法研究,提出了新的规则化边界元法的理论和方法.构造了与法向量关联的两个线性无关的特别切向量,建立与问题基本解有关的量的法向、切向梯度的特性定理,提出转化域积分方程为边界积分方程的极限定理,在此基础上,导出间接变量规则化边界积分方程.与广泛实践的直接边界元法比,本文具有优点：（1）降低了密度函数的连续性要求;（2）更适合求解薄体结构问题.因为所给方程中不含超奇异与几乎超奇异积分,积分的规则化算法更加有效;（3）可计算任何边界位势梯度.数值实施时,C0连续单元描述几何曲面,不连续插值逼近边界量.针对问题的特殊的边界曲面,提出一种精确几何单元.数值算例表明,本文算法稳定、效率高,所得数值结果与精确解相当地吻合.     

潍北凹陷孔店组烃源岩生物标志物特征及地球化学意义

通过对潍北凹陷孔店组烃源岩有机质丰度、类型、成熟度及生物标志物的研究,发现孔店组烃源岩重排甾烷含量低,C27,C28和C29规则甾烷含量较多,C29甾烷的20S/(S R)和C29ββ/(ββ αα)比值分别在0.12～0.38和0.3～0.45之间;在萜类化合物中,奥利烷含量低,γ蜡烷与C30藿烷比值在0.1～0.37之间.研究结果表明孔店组烃源岩生源以高等植物为主,混有一定比例的藻类等低等水生生物,沉积环境为含盐度低的弱还原-弱氧化湖沼相,烃源岩有机质处于低熟-成熟阶段.