ABSTRACT
OBJECTIVES@#To establish a rapid and nondestructive identification method for human body fluid stains and non-biological stains using three-dimensional fluorescence spectroscopy.@*METHODS@#The collected three-dimensional fluorescence spectrum data of human saliva, 3% blood, coffee and Fanta® stains were processed with dimensionality reduction. After wavelet transform, spectral denoising and feature extraction, the classification formula was established. The Fisher discriminant was used for spectrum matching and recognition to establish the analysis method to distinguish stain types.@*RESULTS@#According to the results of data training and comparison, all the recognition accuracies of Fanta®, coffee, saliva and blood were more than 91.39%. Among them, saliva reached 100% recognition accuracy.@*CONCLUSIONS@#Three-dimensional fluorescence spectroscopy is a potential method for rapid and nondestructive identification of biological and non-biological stains.
Subject(s)
Humans , Forensic Medicine/methods , Coloring Agents/analysis , Coffee , Spectrometry, Fluorescence , Body Fluids/chemistryABSTRACT
In addition to obtaining DNA-STR typing of an evidentiary stain for individual identification and paternity tests, knowing the time since deposition (TSD) is also highly desired in forensics. To provide a reference for the research of predicting the TSD, this article reviews the reported optical, cell biological and molecular biological methods of determining the age of bloodstains domestic and overseas, and also introduces the application of microbial forensics, a new field of forensic science, to provide space-time clues of evidentiary stains.
ABSTRACT
Objective Construct a mRNA multiplex amplification system to identify different types of semen stains. Methods First, collect normal, oligozoospermia and azoospermia semen samples to make semen stains. Second, extract total RNA with Qiagen RNeasy Micro Kit. Then use reverse transcript PCR to amplify goal mRNA markers: 2 markers for sperm(PRM1, PRM2), 2 markers for seminal plasma(TGM4, SEMG1) and 2 housekeeping genes(TEF, UCE). Results All semen mRNA markers can be detected in normal semen samples. The RFU of sperm mRNA markers are lower in oligozoospermia semen samples than that in normal controls. No sperm mRNA markers can be detected in the azoospermia semen samples, only seminal plasma specific can be detected. Conclusion The differentiation of normal and azoospermia semen can be achieved by using multiplex mRNA fluorescence amplification system. While normal semen and oligozoospermia semen compared to no statistical difference.
ABSTRACT
One step dot-ELISA method for the rapid determination of ABO blood groups in humam body fluids(or stains)was established using enzyme-labelled anti-A,--B and anti--H monoclonal antibody (McAb).The sample was applied on the nitrocellulose membrance as a dot. After washing, the appropriate McAb wasadded on top of the dot, and then followed by adding 3, 3'-diaminobenzidine(DAB). The brown color indi-cated the positive reaction. The ABO blood typing of 521 saliva samples including both secretor and non-se-cretor were carried out. All the results were correct. The advantages of this method are accurate, sensitive,rapid, easy to perform, as well as not time consuming. It is more sensitive than the conventional hemaggluti-naton inhibition test.