Estimation of post mortem interval by tomographic images of intra-cardiac hypostasis

Lateralized hypostasis of the head on post mortem CT (PMCT) scanning of decomposed bodies-a marker for terminal position

Post-mortem CT (PMCT) scanning was performed on the bodies of two decomposed adult males who had died of natural causes. The bodies both showed changes of marked decomposition with a prominent swelling of tissues on one side of the head compared to the other. A review of police statements confirmed that this matched the positions of the bodies when they were found. Thus, post-mortem hypostasis of putrefactive fluids correlated in both cases with the positions that the bodies had been in when first located. This may be a simple way of identifying or confirming the positions of decomposed bodies after death. It may also assist in indicating whether a body has been moved after putrefactive fluid hypostasis has developed.

Forensic proteomics for the evaluation of the post-mortem decay in bones

Current methods for evaluation the of post-mortem interval (PMI) of skeletal remains suffer from poor accuracy due to the great number of variables that affect the diagenetic process and to the lack of specific guidelines to address this issue. During decomposition, proteins can undergo cumulative decay over the time, resulting in a decrease in the range and abundance of proteins present (i.e., the proteome) in different tissues as well as in an increase of post-translational modifications occurring in these proteins. In this study, we investigate the applicability of bone proteomic analyses to simulated forensic contexts, looking for specific biomarkers that may help the estimation of PMI, as well as evaluate a previously discovered marker for the estimation of biological age. We noticed a reduction of particular plasma and muscle proteins with increasing PMIs, as well as an increased deamidation of biglycan, a protein with a role in modulating bone growth and mineralization. We also corroborated our previous results regarding the use of fetuin-A as a potential biomarker for the estimation of age-at-death, demonstrating the applicability and the great potential that proteomics may have towards forensic sciences.

SIGNIFICANCE

The estimation of the post-mortem interval has a key role in forensic investigations, however nowadays it still suffers from poor reliability, especially when body tissues are heavily decomposed. Here we propose for the first time the application of bone proteomics to the estimation of the time elapsed since death and found several new potential biomarkers to address this, demonstrating the applicability of proteomic analyses to forensic sciences.