质谱成像技术及其在乳腺癌研究中的应用

乳腺癌是女性最常见的恶性肿瘤,其发病率在世界范围内呈现上升趋势,是威胁女性健康的重要疾病之一。随着现代医学技术的快速发展,早期有效的诊断和筛查方法能够改善乳腺癌患者生存率和提高其生活质量。由于乳腺癌肿瘤具有非常显著的异质性,这对于诊断和筛查带来了较大困难,亟须在肿瘤演进时间信息中,继续引入生物分子的空间信息,从而对其异质性、肿瘤微环境等进行准确的追踪。质谱成像技术,可在免标记的前提下利用离子质荷比的特性发现生物组织中的各种分子,并研究这些分子的时间和空间信息,对其进行准确的定性、定量和空间定位。目前,通过质谱成像技术可直接获取药物及其代谢物、内源性代谢物、脂质、多肽和蛋白质等在组织中的空间分布信息,为肿瘤分子分型诊断和确认以及相关抗肿瘤药物的筛选提供了新的思路和研究方向。该综述以乳腺癌相关的生物样品制备和研究进展为主要内容,从小分子样本、大分子样本、石蜡包埋样本、基质喷涂方式、常用离子源等方面阐述质谱成像中样本制备的重要性以及样品制备过程中存在的难点问题。同时,以细胞模型、动物模型和临床肿瘤标本为研究对象,汇总了质谱成像技术在乳腺癌方面的应用进展,并进行了展望,为开展癌症精准分型研究和药物药效的快速筛查提供了重要依据。     

纳米级造影剂在肿瘤影像学诊疗中的基础应用进展

肿瘤的早期诊断对其生存率及预后有极大的意义,医学成像造影剂的应用可极大地提高肿瘤的早期诊断水平。通过新兴纳米技术开发无毒、成像能力更强、循环时间更长的纳米级造影剂是目前研究的热点。本文综述了纳米级造影剂在MRI、CT、US、PET和SPECT等生物医学成像技术中,对于肿瘤诊疗的基础应用,并列举了部分研究实例。纳米级造影剂具有广阔的临床应用前景,未来的研究重点将会是开发集诊断、治疗于一体的多功能的纳米平台。     

短波近红外在体荧光分子成像技术最新进展

癌症的诊断迄今所依赖的主要是一些离体检测方法以及超声波、X射线透视、X射线CT、核磁共振成像和PET等影像学技术. 癌症的确诊则以肿瘤组织或病变细胞的形态和其它宏观特征为依据, 这往往是一个侵入性和耗时的过程, 不适于癌症的早期诊断. 这些影像学技术目前也大都难以发现分子水平上的问题. 因此, 迄今癌症的早期诊断仍然是医学界面临的一个空前挑战. 光学成像方法, 特别是荧光成像方法具有对人体无害、非侵入、高灵敏和可进行在体多目标成像的优点, 随着荧光指示物的不断拓展和检测方法的不断创新, 有望在分子和细胞水平上实现癌症的早期诊断. 本文重点介绍了几项有较重要价值及工作在短波近红外区域的在体荧光成像技术的新进展.     

表面增强拉曼光谱技术在microRNA检测中的研究进展

microRNA是一段长约为18~24个核苷酸的内源性非编码单链RNA. 最新研究发现: 许多疾病和肿瘤的发生与microRNA的表达水平息息相关, 且microRNA有望成为新型肿瘤标志物及癌症治疗的新目标. 因此, 发展高灵敏度、高特异性及简单快速的microRNA分析检测方法对于生物医学研究和癌症的早期诊断具有重要的意义. 表面增强拉曼光谱(SERS)技术由于具有灵敏度高、检测速度快、指纹识别、水干扰小等独特优势, 在癌症的早期诊断领域具有很大的应用价值. 作者综述了SERS技术在microRNA检测方面的最新研究进展, 分析了该技术在生物检测中亟待解决的关键问题和挑战, 并对其未来的发展前景进行了展望.     

高效液相色谱法测定血清中的鸟氨酸脱羧酶活性

建立了血清中鸟氨酸脱羧酶活性的高效液相色谱测定法。结果表明，腐胺在２．８～４５．５μｍｏｌ／Ｌ范围内线性关系良好。最低检测量为０．０５ｎｍｏｌ，回收率为８５．０６％，ＲＳＤ为８．９１％。本法测定正常人及乳腺癌、宫颈癌患者血清中的鸟氨酸脱羧、酶活性发现，乳腺癌及宫颈癌血清中的酶活性升高（ｐ＜０．０５），说明测定血清的鸟氨酸脱羧酶活性，对诊断肿瘤有一定的临床意义。     

西门子研发呼气分析仪

从西门子公司获悉,西门子正在研究一种能利用呼出气体样本对肺结核或肺癌进行早期诊断的方法。该方法能够对患者呼出的气体样本进行分子结构分析。     

口腔癌相关唾液肿瘤生物标志物的分析检测研究进展

口腔癌系头颈部癌，癌组织均位于口腔内，其非侵入性早期诊断是减少该病死亡的有效手段.唾液系口腔癌变相关物质首先释放进入的体液，取材方便，安全无创，是口腔癌普查筛选、早期诊断的首选指标.本文对唾液肿瘤生物标志物的种类、目前国内外常用的检测方法进行概述，重点阐述新型电化学生物传感方法在口腔癌相关唾液肿瘤生物标志物检测方面的相关应用及其最新研究进展.并对口腔癌相关唾液肿瘤生物标志物电化学传感技术的未来发展方向提出展望，拟为其深入研究与应用提供参考.     

循环肿瘤细胞及细胞外囊泡的纳米检测技术

肿瘤液体活检通过对体液中生物标志物的检测实现疾病的精准诊断,对于恶性肿瘤的早期诊断和动态监测至关重要。循环肿瘤细胞(CTC)是肿瘤组织释放到血液中的肿瘤细胞,细胞外囊泡(EV)是由细胞分泌的膜囊泡,二者都携带肿瘤分子信息,并与肿瘤进展和转移密切相关,是重要的液体活检生物标志物,并且在检测方法和临床意义方面也有很多共性。纳米材料由于其高比表面积、独特的光、电、磁等物理化学特性以及易于功能化修饰等特点,被广泛用于CTC和EV的检测,以提高检测灵敏度和特异性,提供肿瘤形成、进展、转移和治疗反应的信息,具有很好的应用前景。本文回顾了在CTC和EV的特异性识别、高效捕获或分离、目标CTC或EV的鉴定等三方面的纳米技术进展,包括提高分子识别特异性的纳米材料表面识别探针功能化修饰以及捕获、鉴定的纳米材料和纳米技术的最新进展,总结了基于功能化纳米材料的液体活检技术的优势及挑战,为液体活检纳米技术的发展提供信息。     

近红外光谱技术结合主成分分析法用于子宫内膜癌的诊断

应用近红外光谱技术结合化学计量学方法研究了子宫内膜癌组织近红外光谱特征提取和早期诊断的可行性. 测定了154 例子宫内膜组织切片的近红外光谱, 选取适宜的波段和光谱预处理方法进行主成分分析, 很好地区分了癌变、增生和正常子宫内膜组织切片, 并且分辨出处于不同分化期的组织切片, 为子宫内膜癌的早期诊断提供了可靠依据. 该法快速、简便, 有望发展成为一种新型的肿瘤无创诊断方法.     

正常与癌症肺组织的傅里叶变换红外光谱差异的研究

傅里叶变换红外(FTIR)光谱可以在分子水平上研究细胞和组织等复杂的生命体系,提供分子结构和组成的信息.我们发展了一种用于直接测定肿瘤及正常组织红外光谱的方法,对16例肺癌及其癌旁正常组织进行了测定.结果表明,对于正常和癌变的肺组织,FTIR光谱中存在显著差异,相关谱带的相对峰高比可以表征这些差异.因此,傅里叶变换红外光谱可以用来诊断癌症与正常的肺组织,有望成为肿瘤快速诊断的新方法.     

中红外光纤光谱法用于甲状腺肿物的体表、 在体及离体检测研究

本文对一些甲状腺患者的肿瘤组织分别进行了体表、术中在体和离体光谱检测研究,探讨了中红外光纤光谱法对甲状腺肿瘤进行无创体表检测的可能性,对术中红外光谱快速判断组织良恶性的规律性进行了系统研究.     

傅里叶变换中红外光纤光谱法用于腮腺肿瘤的检测

采用红外光谱仪与中红外光纤、衰减全反射(ATR)探头联用对40例腮腺肿瘤患者的腺体体表皮肤进行了测定, 并以病人术后肿瘤标本病理观察结果为判断标准, 对良性及恶性肿瘤光谱进行了判别, 发现光谱法判别结果与病理诊断结果基本一致. 实验结果表明, 正常腮腺、良性和恶性腮腺肿瘤体表皮肤的FTIR 光谱中存在显著的差异, 用相关吸收峰的峰形、峰位和峰强可以表征这些差异. 研究进一步发现, 对于不同类型的恶性肿瘤, 其体表组织的红外光谱主要差别在于1500—1000 cm-1区域内峰形及峰位的改变. 根据这一区域的差异可以将恶性肿瘤分为两大类: 一类恶性肿瘤具有上述的光谱特征(如腺泡细胞癌、嗜酸细胞腺癌和腺样囊性癌等), 另一类恶性肿瘤因为类型的不同在1500—1000 cm-1区域内峰形及峰位发生了很大的变化, 不同于上述的光谱特征.     

中红外光纤光谱法在化学反应过程中的应用

将傅里叶变换中红外光纤光谱技术分别用于液相反应体系和固液反应体系的在线监测. 在液相反应体系中, 监测了环烷酸皂化时形成微乳的过程, 初步了解了皂化环烷酸时微乳液的形成机制; 在固液反应体系中, 监测了邻苯二甲酸与氯化铕的配位反应过程, 探索了络合物的生成过程及组分间的相互作用. 该技术有望发展成为一种实时监测化学反应过程的新方法.     

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

The application of molecular spectroscopy inthe biological fields is more and more extensive.Recently vibrational spectroscopy, including FTIRATR Optic Fibers[1—3], FT-IR microspectroscopy[4—6],FT-Raman[7,8] and near IR spectroscopic[9] methods,was used…     

傅里叶变换中红外光谱技术用于人体胃镜样品检测的新方法

应用傅里叶变换红外光谱(FTIR)测定了184例胃镜样品,总结不同病变类型组织的光谱特征,并与病理结果进行比较.实验结果表明,由于不同类型病变组织会在其分子组成和结构上发生相应改变,浅表性胃炎、萎缩性胃炎和胃癌组织具有不同的FTIR光谱,可据此进行胃镜样品疾病类型和病变程度的判别.研究结果表明,FTIR技术有望发展成为一种用于胃镜样品无创、快速、准确的在体临床诊断的新方法.     

Pulsed microchip laser induced fluorescence for in situ tracer experiments

A compact system for remote and non intrusive in situ analysis of fluorescent tracers using a newly developed pulsed microchip laser coupled to fiber optics was used for in situ rhodamine determinations. By using a crystal doubling in front of the microchip Nd-YAG laser, it is possible to obtain 532 nm at 5 kHz with an energy of 0.6 μJ in a 0.5 ns pulse. Using fiber optics and a passive optode, it was possible to analyze remotely the fluorescence of rhodamine with a compact detection system (monochromator and photomultiplier). Limits of detection down to 10^–10–10^–11 mol/L can be reached depending on the rhodamine studied. Such a laser can be directly implanted in the optode avoiding laser losses when exciting in the U.V. Received: 30 July 1997 / Revised: 6 October 1997 / Accepted: 10 October 1997     

Pulsed microchip laser induced fluorescence for in situ tracer experiments

A compact system for remote and non intrusive in situ analysis of fluorescent tracers using a newly developed pulsed microchip laser coupled to fiber optics was used for in situ rhodamine determinations. By using a crystal doubling in front of the microchip Nd-YAG laser, it is possible to obtain 532 nm at 5 kHz with an energy of 0.6 μJ in a 0.5 ns pulse. Using fiber optics and a passive optode, it was possible to analyze remotely the fluorescence of rhodamine with a compact detection system (monochromator and photomultiplier). Limits of detection down to 10^–10–10^–11 mol/L can be reached depending on the rhodamine studied. Such a laser can be directly implanted in the optode avoiding laser losses when exciting in the U.V. Received: 30 July 1997 / Revised: 6 October 1997 / Accepted: 10 October 1997     

Development of non-invasive Raman spectroscopy for in vivo evaluation of bone graft osseointegration in a rat model

The use of bone structural allografts for reconstruction following tumor resection is widespread, although successful incorporation and regeneration remain uncertain. There are few non-invasive methods to fully assess the progress of graft incorporation. Computed tomography and MRI provide information on the morphology of the graft/host interface. Limited information is also available from DXA and ultrasound. Only few techniques can provide information on the metabolic status of the graft, such as the mineral and matrix composition of the regenerated tissue that may provide early indications of graft success or failure. To address this challenge, we discuss here the implementation of Raman spectroscopy for in vivo assessment of allograft implantation in a rat model. An array of optical fibers was developed to allow excitation and collection of Raman spectra through the skin of rat at various positions around the rat's tibia. The system is calibrated against locally constructed phantoms that mimic the morphology, optics and spectroscopy of the rat. The system was evaluated by carrying out transcutaneous Raman measurement on rat. Bone mineral and matrix Raman bands are successfully recovered. This new technology provides a non-invasive method for in vivo monitoring of bone graft osseointegration.     

Application of charge-coupled device technology for measurement of laser light and fluorescence distribution in tumors for photodynamic therapy

Laser and fluorescence light distributions with applications for photodynamic therapy were measured in mouse tumors using a non-invasive electronic optical imaging system. The system consists of a liquid-nitrogen-cooled, charge-coupled-device (CCD) array camera under computer control with 576 x 384 detection elements having dimensions of 23 microns x 23 microns. The available dynamic range of the array is approx. 10(3), and the effective wavelength range is 400-1000 nm. An interstitially placed cylindrical diffusing optical fiber was used to provide tumor illumination. The light distribution pattern from the fiber was determined by immersing the cylindrical diffusing tip in a fluorescing solution and recording the emission image. Fluorescence imaging facilitates an accurate measurement of light intensity distribution while avoiding problems associated with the directional nature of other detection methods used with diffusing fibers. Radiation-induced fibrosarcoma tumors on C3H mice were grown to about 1 cm diameter for in vivo recording of light distribution from the tumor volume and for determination of effective light penetration distance at 18 wavelengths in the range 458-995 nm. Endogenous tumor fluorescence and Photofrin II fluorescence intensity were measured over the wavelength range 585-725 nm to investigate the possible application of CCD imaging technology for drug distribution measurements. Model experiments were begun to evaluate the relative importance of potential distortions of light distribution measurements using this approach.     

Detection of particulate polycyclic aromatic hydrocarbons by laser-induced time-resolved fluorescence

Summary Laser-induced fluorescence is introduced as an analytical technique for the detection of particle-bound PAHs, which can be found as a result of most combustion processes. A quartz fiber is used to couple the light of a frequency-doubled excimer-pumped dye laser into the sensor head. The fluorescence light is detected using collecting optics, a set of interference filters and a photomultiplier. PAHs in different forms (crystalline, as homogeneous particles and coated on NaCl particles) were investigated. Fluorescence spectra and time-resolved signals, which exhibit characteristic decay times, are presented.