الفهرس 
Sexual AssaultOnly 14 pages are availabe for public view
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Abstract
Background: In scenes of sexual assault crimes, biological evidence such as blood, hair, saliva, semen and other body fluid stains are of crucial importance and should be collected. Detection of semen depends upon macroscopic examination, fluorescence techniques (use of ultraviolet light to exploit the fluorescent properties of semen), microscopic examination for presence of spermatozoa, detection of seminal acid phosphatase in the vaginal cavity up to 48 hours after intercourse and analysis for presence of prostate specific antigen (PSA) in the vaginal cavity beyond 8 hours following intercourse. Aim: This study aimed to investigate the effect of time on detection of micro-RNA markers, prostate specific antigen (PSA) and sperms used for semen detection in seminal stains upon exposure to normal laboratory conditions for different periods, and to examine the effect of vaginal secretions on detection of the studied seminal biomarkers. Subjects: This study was performed on samples of semen obtained from seven male volunteers and vaginal swabs obtained from seven female volunteers who were chosen from persons visiting the outpatient clinics of Ain Shams University Hospitals. All subjects were assured about the confidentiality of all data, the findings discovered during examination and preservation of samples. Results: This study was significant decrease of PSA levels with increasing periods of exposure to the environment. This was evident in both of seminal stains and mixed seminal and vaginal stains. There was significant increase in the expression of the studied miRNA biomarkers in mixed stains (semen and vaginal secretions) in comparison to their levels in isolated stains (miR-891a in seminal stains and miR-124a in vaginal secretions stains) after exposure to the environment.