傅里叶红外光谱技术在法医学脑挫裂伤鉴定中的应用展望

脑挫裂伤是常见的一类颅脑损伤,单纯的组织病理学技术可能难以早期发现及精确诊断。傅里叶变换红外面扫描成像技术(FTIR-mapping)是病理学研究领域的新技术,因其结合了傅里叶变换红外光谱、红外显微镜技术以及面扫描成像技术的特点,具有测定方法简便、对样本无损、灵敏度高、准确、直观等优点,突破了传统技术的局限,能检测出发生了物质数量、结构以及构象变化但缺乏明显形态学变化的脑挫裂伤,从而实现早期精准地诊断脑挫裂伤。FTIR-mapping虽已能绘制某些损伤组织的红外光谱病理图像,但其在法医病理学中的价值有待全面深入开发。本文综述了脑挫裂伤的法医病理学研究进展以及傅里叶变换红外面扫描成像技术在法医病理学中的应用。     

CT在法医病理学中的应用与展望

计算机断层扫描(CT)能够对不同密度的人体组织进行成像,在疾病和损伤的检验中具有重要的应用价值,随着CT技术的不断发展和逐步成熟,它可以对组织脏器进行容积再现、多层面重建、最大密度投影、表面遮盖显示等后处理,在肿瘤、血管畸形等疾病的诊断,骨折、关节异位、脏器破裂、出血等损伤的检验,枪弹、爆炸碎片、吸入物等体内异物的检验中具有重要的应用价值。目前已经有不少学者将其应用到相关研究领域当中。本文对近几年国内外应用CT技术进行法医病理学研究的情况进行综述,以便法医病理学研究者了解CT在法医病理学领域中的应用及研究现状,能够为今后的法医病理学科学研究和实践工作提供新的思路。     

法医病理组织学图像简易采集方法

作者在工作中利用智能数码手机的照相功能,利用生物学显微镜以及计数机图像处理系统,组合成一组简易的法医病理组织学图像采集方法,在实际应用过程中体现出图像清晰、图形保真、组织结构层次分明的特点,具有简单、便捷、经济、实用的优点以及容易推广和普遍使用的价值。     

荧光原位杂交技术在法庭科学DNA检验中的应用

目的运用荧光原位杂交技术结合激光显微切割技术,分离法医物证男女混合样本中的男性细胞和女性细胞,并进行DNA分型。方法通过双色荧光原位杂交,Y染色体标记上绿色信号,X染色体标记上红色信号,在荧光显微镜下识别男性细胞和女性细胞,并通过激光显微切割技术分别获得男性细胞和女性细胞进行DNA分型。结果运用荧光原位杂交技术,能够分别标记法医物证男女混合样本中的男性细胞和女性细胞,并通过激光显微切割技术获得各自的DNA分型。结论荧光原位杂交技术结合激光显微切割技术,可应用于法医物证男女混合样本的检验,提高个体识别能力。     

CT技术在骨骼年龄推断研究中应用的进展

法医人类学应用诸多学科的研究方法和先进技术,对个体骨骼识别进行广泛的研究.年龄推断是法医人类学领域中一项重要的研究课题.随着影像学技术的迅速发展,法医人类学家开展了将计算机断层扫描(CT)技术应用于法医人类学领域的研究.CT具有连续快速扫描的成像能力以及强大的图像后处理功能,能够提供多种模式的高分辨骨骼重组图像,对于活体和遗骸的法医人类学鉴定都具有重要意义.本文将综述近年来CT在骨骼年龄推断研究中应用的进展.     

肥厚型心肌病分子机制及法医病理学意义

肥厚型心肌病(hypertrophic cardiomyopathy,HCM)被证实是引发35岁以下青年人(尤其是运动员心源性猝死(sudden cardiac death,SCD)的首要原因。约60%的HCM患者由编码肌小节蛋白的基因突变导致,呈常染色体显性遗传模式。β肌球蛋白重链基因、肌球蛋白结合蛋白C基因、肌钙蛋白T基因、肌钙蛋白I基因被认为是引起HCM最常见的突变基因。基因检测在HCM的临床诊断中已趋于常态化,但在法医工作中应用较少,如果基因检测技术能够应用于法医病理学诊断,将会给HCM猝死案件的死亡原因确认工作提供便利。更重要的是,通过猝死者的基因检测结果尽早进行家庭成员的危险评估才能降低猝死的发生率。本文主要综述了HCM的分子机制进展以及该疾病在法医病理学诊断中的应用价值。     

AIS-ISS评分在法医病理学伤病关系分析中的应用

目的探讨AIS-ISS评分法在法医病理学伤病关系分析中的适用性和局限性。方法收集40例法医病理学伤病关系分析案例,对法医病理学死因分析和AIS-ISS评分结果进行比较。结果 40例案例中,AIS-ISS评分法与法医病理学死因分析评定结果相符的案例为36例,占总数的90.0%,经双变量相关分析,得Kendall相关系数为0.872,Spearman相关系数为0.916,均为P <0.01。4例结果不相符,占总数的10.0%,其中3例为外伤后因急性肺动脉血栓栓塞或脂肪栓塞等严重并发症而死亡,法医病理学死因分析评定结果为外伤与其死亡后果之间存在因果关系,然而原发性损伤较轻;另一例其损伤程度较重,同时伴有较严重的自身疾病,法医病理学死因分析评定结果为外伤与自身疾病共同构成死亡后果,而根据AIS-ISS评分法得出外伤与死亡后果之间存在主要因果关系。结论两种评定结果具有较高的契合度,反映AIS-ISS评分法在法医病理学伤病关系分析中具有良好的应用价值,除了在外伤后因肺动脉血栓栓塞或脂肪栓塞等严重并发症致死的案例中存在局限性之外,AIS-ISS评分法在伤病关系分析中对明确外伤对死亡结果的影响程度方面更具优势,并且AIS-ISS评分法对人体不同部位和器官的损伤进行了量化和分级,其更具客观性,更容易被理解和接受。     

宝鸡市358例法医送检器官的组织病理学分析

目的 分析法医尸体检验后送检器官的病理学特征,总结此类案件的特点.方法 对宝鸡市法医送检358例尸体解剖器官标本进行常规检查并进行组织病理学诊断. 结果 358例中以青壮年男性为主,死亡原因主要为创伤、猝死、中毒.组织学能明确死亡原因250例,无典型组织学病变101例,组织自溶腐败7例.病理诊断以心血管疾病为主,其次为呼吸、神经、消化系统疾病. 结论 法医解剖具有专业特点,与病理解剖不尽相同.组织病理学检验进行死亡原因诊断时,应积极与法医沟通,以充分掌握案情、死亡经过及特定的法医病理学特征.     

DNA定量技术在死亡时间推断中的研究进展

死亡时间推断是法医病理学研究的热点及难点之一.随着分子生物学技术的发展,DNA的定量已广泛应用于死亡时间推断的研究.本文主要对机体死后不同组织和器官中DNA含量随时间的降解情况,以及单细胞凝胶电泳、Feulgen染色图像分析技术、流式细胞仪等近年来新的DNA定量技术应用于死亡时间推断研究中的进展进行了综述.     

数字图像技术辅助二次短路熔痕金相组织定量分析研究

以电气火灾二次短路熔痕显微组织为例，利用显微图像各组元的灰度特性，运用数字图像技术中的图像滤波、图像分割、轮廓提取方法对显微组织图像进行预处理，获取图像晶格和孔洞。结合体视学方法．对显微组织晶格粒径、孔洞大小等几何特征参数进行计算分析与测量，探讨数字图像技术辅助二次短路熔痕金相组织进行定量分析技术方法。     

傅立叶显微红外化学成像在朱墨时序鉴定中的应用研究

目的建立朱墨时序的傅里叶显微红外成像检验方法。方法根据印文及油墨的红外光谱特征峰,使用傅立叶变换红外（FTIR）成像系统直接对纸张上印文及文字油墨进行化学成像,根据成像特征从而判断朱墨时序。结果先打印后盖章的红外成像中油墨字迹的红外成像不完整,有被印章所覆盖的痕迹,而印章的红外成像完整,在字迹中可见印章成像斑点。先盖章后打印的红外成像中油墨字迹的红外成像完整,没有被印章所覆盖,而印章的红外成像不完整,被字迹的油墨所覆盖。结论该方法较传统的鉴定方法更加快速、简单,可以更加直观的反映行文顺序,并且具有不破坏检验样本的特点。     

显微共焦拉曼光谱技术区分喷墨打印机打印的彩色图文墨迹

目的建立显微共焦拉曼光谱法区分喷墨打印机打印的彩色图文墨迹的方法。方法利用显微共焦拉曼光谱技术所具有微量、微区、原位分析及非破坏性等特点,对24种常见彩色墨水墨迹分别进行检验。结果品红色墨点墨迹成分归类区分效果最好,其次是黄色墨点,最后是蓝色墨点。结论采用显微共焦拉曼光谱技术对彩色打印墨迹进行不同颜色单点分析可大大提高喷墨打印机厂家型号的识别率,是一种有效的检测手段。     

High Resolution Imaging of Latent Fingerprints by Localized Corrosion on Brass Surfaces

Abstract:  The Atomic Force Microscope (AFM) is capable of imaging fingerprint ridges on polished brass substrates at an unprecedented level of detail. While exposure to elevated humidity at ambient or slightly raised temperatures does not change the image appreciably, subsequent brief heating in a flame results in complete loss of the sweat deposit and the appearance of pits and trenches. Localized elemental analysis (using EDAX, coupled with SEM imaging) shows the presence of the constituents of salt in the initial deposits. Together with water and atmospheric oxygen—and with thermal enhancement—these are capable of driving a surface corrosion process. This process is sufficiently localized that it has the potential to generate a durable negative topographical image of the fingerprint. AFM examination of surface regions between ridges revealed small deposits (probably microscopic "spatter" of sweat components or transferred particulates) that may ultimately limit the level of ridge detail analysis.     

Image analysis as an adjunct to sodium rhodizonate test in the evaluation of gunshot residues: an experimental study

It is important to investigate the clothing, as well as the body, to determine the range of fire of entry wounds in firearm injuries. Clothing can affect the amount of gunshot residues (GSR) reaching the body and their distribution. The amount and distribution of the GSR also vary according to the distance between the firearm and the target. Sodium rhodizonate test provides valuable data when clothing is available for examination. In the absence of clothing, light microscopic examinations may add additional information regarding the range of fire. In this study, a sodium rhodizonate test was done on 80 garment samples containing the bullet entrance. The 80 calfskin samples were processed histologically and were stained using Alizarin Red S. These were also evaluated with computer-assisted image analysis. Gross residues were seen on military camouflage clothing in samples from < or = 45-cm group. White flannel undershirts under the military camouflage contained rhodizonate-positive particles only around the contact wounds. With image analysis, however, the residues could be detected also in the skin samples of the 2.5-cm- and 5-cm-range groups. We suggest that the image analysis can be combined with other techniques and it can provide valuable data in the determination of entry wounds and also in the estimation of firing distance.     

Reflectance Transformation Imaging (RTI) for the Documentation of Saw Mark Characteristics

Photography is widely accepted as a means of forensic case documentation and evaluation. In cases of criminal dismemberment digital microscopy is commonly used to assess marks left on the bone. Reflectance transformation imaging (RTI) is a computational photography technique which documents and enhances the three-dimensional (3D) reflectance properties of the surface of an object. RTI has primarily been used in the cultural heritage sector but has recently transitioned into forensic science. This study examines the use of RTI for the documentation and presentation of cut surface characteristics on fully sectioned long bones. Juvenile pig radii were bisected using three different handsaws, chosen as handsaws are the most common implement used in criminal dismemberments. The resulting 42 cut surfaces were then documented with a digital microscope and RTI. Four rendering modes were applied to the default RTI image, with diffuse gain being the most beneficial to accentuate cut surface features. Although great care must be taken when obtaining the photographic sequences necessary for detailed RTI analysis, RTI is relatively inexpensive, expeditious, and easy to use, and creates highly detailed, virtually interactive images. RTI may not replace microscopic methods of saw mark analysis, however could prove useful for the documentation, image sharing, and presentation of forensic evidence.     

脑干星形细胞胶质原纤维酸性蛋白免疫组化染色的图像分析

目的探讨脑干星形细胞胶质原纤维酸性蛋白(GFAP)免疫组化染色及其图像分析在原发性脑干损伤鉴定中的应用价值。方法26例原发性脑干损伤致死者的脑干样本,分别在其中脑、脑桥及延脑相同部位取组织作GFAP免疫组化染色(LSAB法),并对GFAP阳性物最密集视野做图像分析。21例非颅脑损伤或脑部病变死亡者的脑干作对照样本,所得图像参数测量值进行统计学分析。结果(1)对照组星形细胞的GFAP阳性染色在中脑、脑桥及延脑三个部位分布不等(P<0.05),延脑>中脑>脑桥;损伤组则三个部位无显著性差异(P>0.05);(2)对照组与损伤组相比,GFAP阳性染色细胞的数量在中脑、脑桥及延脑等三个部位中差异均有显著性(P<0.01);(3)死后96h后解剖者,损伤组与对照组有显著差异;(4)伤后30min内死亡者,损伤组与对照组也有显著差异。结论人脑干星形细胞GFAP免疫组化染色的图像分析,对法医学鉴定原发性脑干损伤具有重要参考价值。     

The Classification of Inkjet Inks Using AccuTOF™ DART™ (Direct Analysis in Real Time) Mass Spectrometry—A Preliminary Study

A novel approach for the analysis of inkjet inks is being reported. A time‐of‐flight mass spectrometer, coupled with a Direct Analysis in Real Time (DART?) ion source (AccuTOF? DART?), was used to determine if inkjet inks from various manufacturers and models of printers could be reliably differentiated, characterized, and identified. A total of 217 ink standards were analyzed. As inkjet printing often involves the use of multiple colors (e.g., cyan, magenta, yellow, and black) to form an image or text, two different approaches to creating a library of standards and sampling methods were evaluated for implementation in a standard operating procedure. This research will show that a microscopic examination of the region of interest is requisite to identify what colors were utilized during the printing process, prior to comparing with known standards. Finally, blind testing was administered with 10 unknown samples to assess the validity and accuracy of the methodology.     

Correlation of microscopic and mitochondrial DNA hair comparisons

Expert opinions regarding the microscopic comparison of human hairs have been accepted routinely in courts for decades. However, with the advent of mitochondrial DNA (mtDNA) sequencing, an assessment can be made of the association by microscopic hair comparisons in casework between a questioned hair and reference hairs from an individual. While each method can be used separately, the two analytical methods can be complementary and together can provide additional information regarding source association. Human hairs submitted to the FBI Laboratory for analysis between 1996 and 2000 were reviewed. Of 170 hair examinations, there were 80 microscopic associations; of these, only nine were excluded by mtDNA. Importantly, 66 hairs that were considered either unsuitable for microscopic examinations or yielded inconclusive microscopic associations provided mtDNA results. Only six hairs did not provide sufficient mtDNA, and only three yielded inconclusive results. Consistency was observed in exculpatory results with the two procedures. This study demonstrates the utility of microscopic hair examinations and the strength of combining microscopic analysis with mtDNA sequencing.     

Hair-MAP: a prototype automated system for forensic hair comparison and analysis

This paper demonstrates the feasibility of the automation of forensic hair analysis and comparison task using neural network explanation systems (NNESs). Our system takes as input microscopic images of two hairs and produces a classification decision as to whether or not the hairs came from the same person. Hair images were captured using a NEXTDimension video board in a NEXTDimension color turbo computer, connected to a video camera. Image processing was done on an SGI indigo workstation. Each image is segmented into a number of pieces appropriate for classification of different features. A variety of image processing techniques are used to enhance this information. Use of wavelet analysis and the Haralick texture algorithm to pre-process data has allowed us to compress large amounts of data into smaller, yet representative data. Neural networks are then used for feature classification. Finally, statistical tests determine the degree of match between the resulting collection of hair feature vectors. An important issue in automation of any task in criminal investigations is the reliability and understandability of the resulting system. To address this concern, we have developed methods to facilitate explanation of neural network's behavior using a decision tree. The system was able to achieve a performance of 83% hair match accuracy, using 5 of the 21 morphological characteristics used by experts. This shows promise for the usefulness of a fuller scale system. While an automated system would not replace the expert, it would make the task easier by providing a means for pre-processing the large amount of data with which the expert must contend.