On-Scene Body Assessment
Kevin L. Erskine, Erica J. Armstrong in Water-Related Death Investigation, 2021
Under controlled laboratory conditions of ambient temperature, it has been demonstrated that a body will cool at a certain rate over time: 1.5°F per hour for the first 12 hours after death, then 1°F for the next 12–18 hours. As an adjunct to the known approximate cooling rates, a formula can be applied to help further approximate the postmortem interval (PMI) or the amount of time elapsed since death. This is called Moritz’s formula: 98.6°F – rectal temperature/1.5 = hours since death).2 This formula assumes that the body temperature at the time of death is normal (98.6°F), which may or may not be the case and may be unknown. This formula will be further compounded if the body temperature at death is much higher or much lower than normal. Application of formula and knowledge of rates of cooling can only be applied in ideal conditions of a temperate, ambient environment without wind currents or cold water immersion. Additionally, there are many variables that can affect the rate of cooling, such as clothing, body habitus (obese vs. thin), weather, temperature of surface or object in contact with the body, and body temperature at the time of death. Medical conditions, use of illicit drugs or certain medications, head injury, and heat stroke are additional variables.2 The frequent lack of ideal environmental conditions and the presence of variables make the estimation of time since death using algor mortis tenuous.
The appearance of the body after death
Jason Payne-James, Richard Jones in Simpson's Forensic Medicine, 2019
Opinions on the post mortem interval (PMI) are frequently sought from forensic practitioners. For a forensic pathologist an estimation of PMI is based on the pathological findings. While none of the changes after death is capable of providing a precise ‘marker’ of PMI, the most reliable would appear to be related to the cooling of the body after death, where appropriate measurements have been recorded.
Environmental and Exposure-Related Deaths
John M. Wayne, Cynthia A. Schandl, S. Erin Presnell in Forensic Pathology Review, 2017
Answer C is correct. Rigor mortis, a common metric used to assist in postmortem interval estimation, cannot be assessed when significant thermal injury is present due to the heat contraction of the skeletal muscles, often “fixing” limbs in place.
mRNA expression of the P5 ATPase ATP13A4 is increased in Broca’s area from subjects with schizophrenia
Published in The World Journal of Biological Psychiatry, 2020
Andrew S. Gibbons, Laura M. Bell, Madhara Udawela, Brian Dean
Human tissue was sourced through the Victorian Brain Bank Network, Florey Institute of Neuroscience and Mental Health, following approval from the Ethics Committee of the Victorian Institute of Forensic Medicine. Cadavers were refrigerated within 5 h and the brains frozen to –70 °C within 30 min of autopsy. Post-mortem interval (PMI) was measured from the time of death or, where death was not witnessed, the midpoint between the subject being found and being last seen alive, to the time of autopsy. CNS pH was measured as described previously (Kingsbury et al. 1995). Duration of illness (Hx) was taken as the time from first presentation with psychiatric symptoms to the time of death. The final recorded doses (FRADD) and lifetime dosages of antipsychotic drugs (LADD) were recorded and standardised to mg/day chlorpromazine equivalents.
SMAD4 protein is decreased in the dorsolateral prefrontal and anterior cingulate cortices in schizophrenia
Published in The World Journal of Biological Psychiatry, 2021
Andrew S. Gibbons, Daniel Hoyer, Brian Dean
All human tissue was sourced through the Victorian Brain Bank Network, Florey Institute of Neuroscience and Mental Health. Approval for the study was granted by the Ethics Committee of the Victorian Institute of Forensic Medicine. For each subject, a case history review was completed using the Diagnostic Instrument for Brain Studies (DIBS) (Hill et al. 1996; Roberts et al. 1998) and a consensus diagnosis reached by two psychiatrists and a psychologist. To reduce the impact of autolysis, cadavers were refrigerated within 5 h and the brains were frozen to −70 °C within 30 min of autopsy (Ferrer et al. 2007). Post-mortem interval (PMI) was calculated from the time death to that of autopsy. Where death was not witnessed, time of death was taken as the midpoint between the subject being found and being last seen alive. Subjects, who were found dead more than 5 h since being witnessed alive, were excluded from the study. The pH of the CNS was measured as described previously (Kingsbury et al. 1995). Duration of illness (DOI) was taken as the time from first presentation with psychiatric symptoms to the time of death. The final recorded antipsychotic drug doses (FRADD) were recorded and standardised to chlorpromazine equivalents.
An overview of lipidomics utilizing cadaver derived biological samples
Published in Expert Review of Proteomics, 2021
Luheng Lyu, Neel Sonik, Sanjoy Bhattacharya
Forensic lipidomics and Postmortomics: The establishment of a timeline is extremely important in the solving of fatal crimes. The current method to calculate Postmortem Interval (PMI) has significant shortfalls as it relies heavily on the experience and the opinion of the investigator, often rendering this metric as subjective and unreliable. Similar to the use of lipidomics for anthropogenic studies, lipidomics are a powerful addition to the arsenal of investigative and corroborative tools in the repertoire of modalities used for the collection of forensic evidence. This is also relevant for holistic postmortem ‘Omics’ or ‘multi-omics’ studies. Of course, since they utilize cadaveric tissues, all the questions raised above regarding error in the data (Figure 1) are relevant for these studies as well. It is imperative to find biomarkers that provide better, more accurate estimates of the time of death in an objective manner [49].
Related Knowledge Centers
- Algor Mortis
- Chemistry
- Death
- Eye
- Livor Mortis
- Rigor Mortis
- Stages of Death
- Forensic Science
- Forensic Pathology
- Decomposition