The effect of cyanide exposure to larvae weight for post mortem interval estimation

Flies are one type of insect, which decompose the organic component in animals, and human cadavers. Therefore, the insects can be used to help the investigators related to human law. One of the methods to determine Post Mortem Interval [PMI] was by identifying the insects that come in the decay process. Some chemicals can affect the development of the insect and its life cycle. Cyanide is widely used to commit murder in Indonesia. The effect of cyanide on the development and life cycle of insects is a very interesting field to study. The purpose of this study was to determine the effect of cyanide exposure to larvae weight for PMI estimation. This research was an experimental research that used larvae of Wistar rat carcass. The control group was killed by neck dislocation, while experimental group were killed by oral lethal doses of cyanide. Data were obtained from the measurement and examination of larvae, started from the 1st day until 4th day after death. Chrysomya, Sarcophaga, and Lucilia larvae were identified from this study. Sarcophaga larvae first appeared and next day followed by Chrysomya and Lucilia. There were significant differences in Chrysomya larvae weight. There were Chrysomya third instar larvae on the 4th day on cyanide group, with 56.4±16.8 mg of weight. There were Chrysomya third instar larvae on the 4th day on control group, with 30.4±5.5 mg of weight. The differences of larvae’s weight, among Sarcophaga and Lucilia larvae, could not be determined because there were not enough samples. Chrysomya third instar larvae of cyanide group significantly heavier than control group on 4th day. The differences of larvae weight, among Sarcophaga and Lucilia larvae, could not be determined because there were not enough samples.

Download Full-text

Post-Mortem Interval Estimation Based on Insect Evidence: Current Challenges

Insects ◽

10.3390/insects12040314 ◽

2021 ◽

Vol 12 (4) ◽

pp. 314

Author(s):

Szymon Matuszewski

Keyword(s):

Forensic Entomology ◽

Interval Estimation ◽

Review Literature ◽

Error Rates ◽

Post Mortem ◽

Post Mortem Interval ◽

Research Areas ◽

Pmi Estimation

During death investigations insects are used mostly to estimate the post-mortem interval (PMI). These estimates are only as good as they are close to the true PMI. Therefore, the major challenge for forensic entomology is to reduce the estimation inaccuracy. Here, I review literature in this field to identify research areas that may contribute to the increase in the accuracy of PMI estimation. I conclude that research on the development and succession of carrion insects, thermogenesis in aggregations of their larvae and error rates of the PMI estimation protocols should be prioritized. Challenges of educational and promotional nature are discussed as well, particularly in relation to the collection of insect evidence.

Download Full-text

POST-MORTEM INTERVAL ESTIMATION BY CEREBRO-SPINAL FLUID FILMS POLARIZATION IMAGES OPTICAL STRUCTURE CHANGING

CBU International Conference Proceedings ◽

10.12955/cbup.v4.838 ◽

2016 ◽

Vol 4 ◽

pp. 711-718

Author(s):

Marta Garazdiuk ◽

Viktor Bachynskіy ◽

Oleg Wanchuliak ◽

Oleksandr Garazdiuk ◽

Aleksandr Ushenko

Keyword(s):

Optical Networks ◽

Interval Estimation ◽

Two Dimensional ◽

Post Mortem ◽

Polycrystalline Films ◽

Fluid Films ◽

Post Mortem Interval ◽

Optimal Interval ◽

Optical Structure ◽

Pmi Estimation

INTRODUCTION: Post-mortem interval (PMI) estimation has been and remains one of the main issues of forensic medicine. Complex photometric, polarization, and correlation techniques of biological tissue (BT) structure are crucial in this area.OBJECTIVES: The purpose of this study is to develop and test two-dimensional Stokes-polarimetric mapping of biological layers to evaluate the accuracy of PMI assessments using statistical analysis of post-mortem changes and dynamics of the coordinate distributions for the polarization ellipticity (PE) images of polycrystalline films of liquor (PFL). Coordinate distributions of polarization ellipticity (PE) image values were estimated for each sample of PFL in the optical arrangement of the Stokes polarimeter using the method of two-dimensional distributions of Stokes-parameters.RESULTS: The most sensitive statistics to the post-mortem manifestations in terms of changes to liquor polycrystalline optical networks were those for the 3rd and 4th order. They characterized asymmetry and kurtosis (peak sharpness) of coordinate distributions for polarization ellipticity images of polycrystalline films of liquor. The optimal interval was 32 hours, with accuracy of 60 min, from the method of two-dimensional Stokes-polarimetric mapping used.

Download Full-text

Caspase 9 and Caspase 3 Immunohistochemical Pattern in Skeletal and Cardiac Muscles at Different Times after Death: An Experimental Study on PMI Estimation

Diagnostics ◽

10.3390/diagnostics11061062 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1062

Author(s):

Cristina Mondello ◽

Chiara Stassi ◽

Letteria Minutoli ◽

Gennaro Baldino ◽

Angela Alibrandi ◽

...

Keyword(s):

Caspase 3 ◽

Potential Role ◽

Interval Estimation ◽

Immunohistochemical Analysis ◽

Post Mortem ◽

Caspase 9 ◽

Post Mortem Interval ◽

Cardiac Muscles ◽

Preliminary Activation ◽

Pmi Estimation

(1) Background: The estimation of the post mortem interval (PMI) is a challenge for forensic pathologists because data emerging from methods commonly applied are not always conclusive, since several conditions exist that may affect the reliability of these parameters. Thus, new approaches have been proposed to overcome such a limit. In recent years, several studies have been performed on proteins analyzing their expression/degradation patterns in relation to the progressing of the post mortem interval. (2) Methods: The immunoreactivity patterns of two apoptosis mediators—Caspase 9 and Caspase 3—have been tested in order to evaluate their potential role as markers of the post mortem interval. The immunohistochemical analysis was performed on samples of skeletal and cardiac muscles obtained from rats at 0, 4, 8, 12, 24 and 72 h after death. (3) Results: The observed immunoreactivity patterns of both Caspase 9 and Caspase 3 showed a significant correlation with increasing post mortem interval either in skeletal or cardiac muscles, while the comparison of the immunoreactivity patterns of the two apoptotic mediators within each tissue appeared consistent with a preliminary activation of the “initiator” Caspase 9, which, in turn, subsequently activates the “executioner” Caspase 3. (4) Conclusion: The different expressions and decrease immunohistochemically observed on both caspases with progressing PMI support the usefulness of the combined analysis for post mortem interval estimation.

Download Full-text