An improved method for post-PCR purification for mtDNA sequence analysis

Mitochondrial DNA (mtDNA) analysis of forensic samples typically is performed when the quantity and quality of DNA are insufficient for nuclear DNA analysis or when maternal relatives may be the only reference source. Many of the steps required in the analytical process are both lengthy and labor intensive. Therefore, improvements in the process that reduce labor without compromising the quality of the data are desirable. The current procedure requires purification of the amplicons by centrifugal filtration after PCR and prior to cycle sequencing. Because this method requires several manipulations to perform, alternate cleanup procedures were investigated. These include the use of 1) Qiagen QlAquick PCR Purification columns, 2) Concert Rapid PCR Purification columns, and 3) ExoSAP-IT reagent. When the yield of purified amplicons, quality of the sequence profile, and ease of assay were evaluated, the use of ExoSAP-IT reagent for post-amplification purification was chosen to replace the filtration method.     

PMS,psychosis and culpability: sound or misguided defense?

Premenstrual Syndrome (PMS) is believed to affect up to 90% of women of reproductive age. A small subset of women have been identified who actually experience psychotic symptoms in the premenstrual phase of their cycles. Not surprisingly, PMS has made it into the courts where it has been offered as a defense for criminal acts. The defense has generally fared poorly in the United States, although it has been successfully used as a factor in supporting diminished capacity in Great Britain. The following paper sets out to review the medical literature on premenstrual syndrome with a particular focus on premenstrual psychosis. Available literature from both medical and legal sources is then utilized to investigate instances in which premenstrual psychosis has been invoked as a defense in the courts.     

Estimation of body exposure to explosion

An ordnance-disposal expert was killed while disposing of a cache of explosives. The likely position of the body was reconstructed by modeling the explosion as an omnidirectional emission of particles from a model of the explosion site and noting the distribution of particles on a model of a human. The applications and limitations of this method in reconstructing the events and correlation with the injuries noted at autopsy are discussed.     

Understanding Children's Use of Secrecy in the Context of Eyewitness Reports

To investigate socioemotional influences on children's eyewitness accuracy, we examined children's reports for activities they were motivated to conceal. Forty-eight 3–6-year-old children participated in a standardized play session with their mothers. Half of the children were told by an experimenter not to play with certain toys, but did so at the urging of their mothers, who told their children to keep the play activities secret. The remaining children were not restricted from playing with the toys, nor told by their mothers to keep the play activities secret. Later, all children were interviewed about the activities with free narrative and detailed questions. Half were given an interview that consisted of highly suggestive questions; half were given an interview consisting of specific, less suggestive questions. Results indicated that older children who were instructed to keep events secret withheld more information than did older children not told to keep events secret. Younger children's reports were not significantly affected by the secret manipulation. There were no significant effects associated with interview type. We discuss implications for understanding the development of children's knowledge and use of secrecy, and applications of the research to issues that arise when child witnesses give reports in legal contexts.     

Personal identification based on radiographic vertebral features

Personal identification of human remains constitutes about 10% of the normal caseload of any forensic medicine practice. Identification can be achieved by a variety of methods, one of which is the comparison of antemortem and postmortem radiographs. There are numerous accounts of cranial and dental radiographic features useful for identification, whereas the availability of postcranial radiographs and especially plates that depict the vertebral column is less widespread among the forensic community. The authors here review the various vertebral features instrumental in positive identification that can be identified on radiographs of the spine.     

A study of the effects of a Micelle Encapsulator Fire Suppression Agent on dynamic headspace analysis of fire debris samples

The effects of a Micelle Encapsulator Fire Suppression Agent (F-500, Hazard Control Technologies Inc., Fayetteville, Georgia) on the routine analysis of fire debris samples by Gas Chromatography (GC) were studied. When mixed with water the product can be used in the suppression of Class A and Class B fires. Laboratory tests were performed to determine whether or not the product has any effect on the analysis for ignitable liquids by GC, in particular for gasoline, medium petroleum distillates. and heavy petroleum distillates. Test burns were suppressed using either the micelle encapsulator or water and samples collected from these burns were analyzed. The results of analysis show that use of the micelle encapsulator at a fire scene may affect the chromatographic data obtained from samples collected by the investigator. However, the effect does not prevent the identification of common ignitable liquids in fire debris samples.     

Detection of ketosis in vitreous at autopsy after embalming

Ketosis occurs in ketoacidosis or malnourishment. When either is suspected in relation to a death, it may be important to analyze for ketosis at autopsy. We encountered a case where starvation was suspected in a deceased nursing home resident, where the body had been embalmed prior to autopsy. Gas chromatography (GC) was unable to separate acetone from formaldehyde, a component of embalming fluid. The Acetest is a simple test that can detect acetone and acetoacetate in body fluids. We validated the Acetest with GC on vitreous. The Acetest and GC were consistent except at very low levels of acetone or acetoacetate. The sensitivity of the Acetest for acetoacetate in vitreous was 10 mg/dL, consistent with early starvation. Significant interference from embalming fluid did not occur. The Acetest was negative in the described case. The Acetest is a simple and useful test for the detection of ketosis in embalmed autopsies.