[New Progress of MALDI-TOF-IMS in the Study of Proteomics].

Matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry (MALDI-TOF-IMS) has been a classical technique for studying proteomics in present and a tool for analyzing the distribution of proteins and small molecules within biological tissue sections. MALDI-TOF-IMS can analyze multiple unknown compounds in biological tissue sections simultaneously through a single measurement which can obtain molecule imaging of the tissue while maintaining the integrity of cellular and molecules in tissue. In recent years, imaging mass spectrometry technique develops relatively quickly in all biomedical domain. This paper based on the relevant data and reviews the present developing level of MALDI-TOF-IMS, the principle of imaging mass spectrometry, methology and the prospect in forensic pathology.

[Proteomic Analysis of Rat Brain Stem with DAI by MALDI-TOF-MS].

OBJECTIVE: To establish a diagnostic model for diffuse axonal injury (DAI) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). To screen the proteins or peptides associated with DAI for providing the biomarkers with theoretic foundation. METHODS: Fifteen male Sprague-Dawley rats were randomly divided into DAI group (n = 10) and control group (n = 5). The protein or peptide expression profiles of rat brain stem were detected by MALDI-TOF-MS. ClinProTools 2.2 software was used to find specific peaks, and a diagnostic model was established by the genetic algorithm. RESULTS: There were significant differences in 61 peaks of DAI group (P < 0.05), 9 peaks were down-regulated and 52 up-regulated. The diagnostic model was established based on 5 different peaks. The specificity and sensitivity of cross validation was 96.14% and 95.98%; while the specificity and sensitivity of blind validation showed was 73.33% and 70.00%, respectively. CONCLUSION: A specific and sensitive diagnostic model of DAI can be established by MALDI-TOF-MS to provide a potential value for determining DAI in forensic practice.