OBJECTIVE: To observe changes of the length of sarcomere of rat when restiffening. METHODS: We measured the length of sarcomere of quadriceps in 40 rats in different condition by scanning electron microscope. RESULTS: The length of sarcomere of rigor mortis without destroy is obviously shorter than that of restiffening. CONCLUSION The length of sarcomere is negatively correlative to the intensity of rigor mortis. Measuring the length of sarcomere can determine the intensity of rigor mortis and provide evidence for estimation of time since death.
Animals ; Female ; Male ; Microscopy, Electron ; Postmortem Changes ; Rats ; Rats, Wistar ; Rigor Mortis/pathology* ; Sarcomeres/ultrastructure* ; Time Factors

OBJECTIVE: To compare the pathomorphologic changes between the pancreas in acute necrotizing pancreatitis (ANP) and that in acute deaths of rats (within 48 hours) so as to find the distinctions. METHODS: The animal models of ANP and other acute deaths (electroshock, mechanic asphyxia/strangle, and acute poisoning with tetramine) were established according to the criteria. Half-quantitative grading and image quantitative analysis methods were employed to observe the gross and microscopic changes of the pancreases. RESULTS: Three features including inflammation infiltrate, fat necrosis and calcium deposit in the ANP group were considerably different from that in other acutely died rat group (P<0.05). CONCLUSION Inflammation infiltrate, fat necrosis and calcium deposit are the most important pathologic features found in ANP by common light microscope, distinguishing ANP from postmortem pancreatic autolysis.
Animals ; Autolysis ; Female ; Forensic Pathology ; Male ; Pancreas/pathology* ; Pancreatitis, Acute Necrotizing/pathology* ; Poisoning/pathology* ; Postmortem Changes ; Rats ; Rats, Sprague-Dawley

The postmortem interval (PMI) estimation is a key and difficult point in the practice of forensic medicine, and forensic scientists at home and abroad have been searching for objective, quantifiable and accurate methods of PMI estimation. With the development and combination of high-throughput sequencing technology and artificial intelligence technology, the establishment of PMI model based on the succession of the microbial community on corpses has become a research focus in the field of forensic medicine. This paper reviews the technical methods, research applications and influencing factors of microbial community in PMI estimation explored by using high-throughput sequencing technology, to provide a reference for the related research on the use of microbial community to estimate PMI.
Humans ; Postmortem Changes ; Artificial Intelligence ; Autopsy ; Cadaver ; Microbiota

Forensic entomology provides a feasible way to estimate postmortem interval (PMI), of which the growth and development of sarcosaprophagous insects is the most widely used indicator in forensic practice. Over the years, forensic entomologists have carried out a large number of studies on the development biology of sarcosaprophagous insects. This paper illustrates the main factors that affect the development of sarcosaprophagous insects, including temperature, humidity, light, food types and poisons. The development indicators of sarcosaprophagous insects were reviewed from the perspectives of morphology, differential gene expression and biochemical characteristics. It is emphasized that future research of development biology on sarcosaprophagous insects should fully absorb and integrate the methods of artificial intelligence and omics, and the research object also needs further expansion in order to establish a more objective and more accurate PMI estimation method.
Animals ; Artificial Intelligence ; Developmental Biology ; Diptera ; Entomology ; Insecta ; Postmortem Changes

Investigation of the cause of death during diving is one of the contents of forensic pathology. In this article, relevant foreign literature is reviewed to summarize the techniques and methods used in the identification of diving deaths, such as accident reconstruction, diving monitoring data, postmortem CT examination and gas analysis (location and quantity) in the body of the corpse, in order to provide a reference for forensic identification of such cases.
Autopsy/methods* ; Diving ; Forensic Medicine ; Forensic Pathology ; Humans ; Postmortem Changes

In recent years, postmortem biochemistry analysis has gradually been applied to forensic practice, providing objective evidence for health conditions before death, disease pathophysiological processes and forensic diagnosis of postmortem interval and cause of death. It is of great significance to understand the change patterns of postmortem biochemical indicators and their applications in forensic medicine. This article reviews the research progress of postmortem biochemistry and its application in forensic medicine, it summarizes the existing problems of postmortem biochemistry analysis in forensic medicine of China and discusses the application prospect of postmortem biochemistry analysis in forensic medicine. This review is expected to provide references for forensic practitioners.
Autopsy/methods* ; China ; Forensic Medicine ; Forensic Pathology ; Humans ; Postmortem Changes

Autopsy ; Drowning/diagnosis* ; Forensic Pathology ; Humans ; Lung ; Postmortem Changes ; Water

OBJECTIVES: To study the relationship between water temperature and floating time of aquatic cadavers, providing a reference for more precise positioning and searching for floating corpses. METHODS: The floating model of guinea pig after drowning at 17-30 ℃ was established, and the floating times of carcasses were recorded. The collected data of 32 floating corpse cases in the Pearl River were sorted out and analyzed according to the floating time of corpses corresponding to each degree of water temperature. The relationship models between water temperature and the floating time of guinea pig carcass, and between that and the floating time of real cases were established. RESULTS: The floating time of the cadaver was negatively correlated with water temperature. The power function fitting equation of the relationship between floating time and water temperature of guinea pig carcass was y=1×10¹⁵x^-10.530(R²=0.871, P<0.01), and the power function fitting equation of the relationship between corpse floating time and water temperature was y=3×10⁶x^-3.467(R²=0.802, P<0.01). CONCLUSIONS It is found that average floating cadaver time has a power function with water temperature, which provides a reference for locating floating cadavers and establishing search models.
Animals ; Cadaver ; Drowning ; Guinea Pigs ; Postmortem Changes ; Rivers ; Temperature ; Water

Estimation of postmortem interval (PMI) is one of the important research contents in forensic pathology, and it has always been the focus and hot spot of research work. In recent years, scholars at home and abroad have made some research progress in estimating PMI by using ocular tissue. After death, the changes of cornea, aqueous humor, iris, lens, vitreous humor and retina all show time sequence change rule highly related to PMI. This paper reviews the research progress of PMI estimation based on the morphological, biochemical, molecular and genetic material changes of different ocular tissue structures after death, and discusses the existing problems and development trends.
Humans ; Postmortem Changes ; Time Factors ; Autopsy ; Vitreous Body ; Forensic Pathology

It is a difficult problem of forensic medicine to accurately estimate the post-mortem interval. Entomological approach has been regarded as an effective way to estimate the post-mortem interval. The developmental biology of carrion-breeding flies has an important position at the post-mortem interval estimation. Phorid flies are tiny and occur as the main or even the only insect evidence in relatively enclosed environments. This paper reviews the research progress of carrion-breeding phorid flies for estimating post-mortem interval in forensic medicine which includes their roles, species identification and age determination of immatures.
Animals ; Autopsy ; Diptera ; Entomology ; Environment ; Forensic Medicine ; Humans ; Postmortem Changes