Related Experiment Videos
Post-mortem analysis of apoptotic changes associated with human skin bruises
T Sawaguchi1, B Jasani, M Kobayashi
1Wales Institute of Forensic Medicine, Department of Pathology, University of Wales College of Medicine, Cardiff, UK. tsawagu@research.twmu.ac.jp
Forensic Science International
|March 29, 2000
Summary
Estimating bruise age in forensic medicine is crucial. Apoptotic cell density, identified by the TUNEL method, shows a time-dependent increase in bruised skin, aiding age estimation within six days post-mortem.
Area of Science:
- Forensic Medicine
- Dermatology
- Cell Biology
Background:
- Accurate age estimation of skin bruises is vital in forensic investigations, particularly in cases of suspected child abuse.
- Current methods relying on bruise color and histology have limited accuracy.
- Apoptosis (programmed cell death) is explored as a novel time-dependent marker for tissue injury.
Purpose of the Study:
- To apply the TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labeling) method to quantify apoptotic cells in bruised skin.
- To investigate the relationship between apoptotic cell density and the age of skin bruises.
- To establish the utility of apoptosis as a reliable biomarker for bruise dating.
Main Methods:
- Standardization and validation of a commercial TUNEL assay kit.
- Analysis of 20 post-mortem skin specimens with bruises of various origins.
- Counting TUNEL-positive apoptotic cells in epidermal and dermal layers of formaldehyde-fixed, paraffin-embedded tissues.
Main Results:
- Significantly higher mean apoptotic cell counts were observed in bruised epidermis compared to normal skin for bruises aged 2-6 days.
- A statistically significant increase in apoptotic cells in bruised dermis was noted for bruises aged 3-8 days.
- A quiescent period precedes the rise in apoptotic activity post-bruising.
Conclusions:
- Apoptotic cell density, assessed via TUNEL staining, serves as a valuable indicator for estimating the age of skin bruises.
- The findings suggest a temporal pattern of apoptotic response following skin injury.
- Accurate bruise age estimation using this method is feasible for post-mortem samples collected within six days of death to avoid post-mortem interval bias.