我国法医昆虫学的研究进展

法医昆虫学是应用昆虫学知识解决有关法律问题的法医学分支学科。在推断死亡时间等方面具有明显优势。本文在阐述法医昆虫学定义和研究内容基础上,综述尸体上的昆虫生态群落演替现象、昆虫发育形态学、DNA分析技术的应用、法医昆虫毒理学等法医昆虫学问题在我国的研究进展。     

Social isolation and delayed discovery of bodies in houses: the value of forensic pathology, anthropology, odontology and entomology in the medico-legal investigation

The bodies of socially isolated people may remain undiscovered in their own houses for prolonged periods. Occasionally the body is in situ for sufficient time to become skeletonised, or partially so. Medico-legal investigation of these cases is complicated by degradation and contamination of evidence. Thus, a multidisciplinary forensic investigation is recommended. The potential contributions of forensic pathology, anthropology, odontology and entomology are outlined here with reference to two cases that occurred in Victoria, Australia, in 2003. Forensic pathologists are often unable to determine the cause of death in skeletonised bodies, however, they may find evidence to support either a natural or unnatural mode of death, and they may describe skeletal pathology or trauma, and identify skeletal features to support radiological identification of the deceased. Anthropologists can provide supplementary evidence of skeletal trauma. Additionally, they can assess age, sex, stature and racial affiliation from skeletal remains. Odontologists can identify individuals through comparison with ante-mortem dental records; however, potential difficulties exist in identifying the treating dentist of a socially isolated person. Odontologists may also examine the teeth and oro-facial skeleton for trauma. Entomologists may estimate minimum death time and/or season of death. Entomological examination of insect remains may also confirm that a body has lain in situ for a considerable period.     

Practice of forensic entomology--usability of insect fragments in the estimation of the time of death

Forensic entomology analyzes and evaluates the presence of necrophagous or necrophilic insects on human corpses to estimate the post-mortem interval. The three cases presented are good examples illustrating that not only the various stages of development of the necrophagous insects from egg via larva to pupa are useful for forensic assessment. Depending on the situation in the individual case, even inconspicuous remains of past insect activity such as empty pupal cases or larval skins may supply important entomological information. For this purpose it is indispensable to preserve such evidence, which may appear only as fragments or pieces at first sight, for proper entomological assessment.     

Application of HRM-PCR (high resolution melting PCR) for identification of forensically important Coleoptera species

Precise estimation time of death is one of key task of forensic entomology. Especially interesting is Coleofauna present at all stages of cadaver decomposition. The morphological identification of Coleoptera species from varying life stages to species level is time-consuming and needs highly qualified entomologists. Among different molecular methods of species identification very promising is high-resolution melting PCR. It allows fast single-tube assignment of analyzed sample to species based on amplicon melting profile. The object of this study were different specimens of Coleoptera collected at pig cadavers in Łomna (central Poland) during 2012 - 2014. Specimes were identified to species by experts of corresponding Coleoptera families. From 120 collected specimens belonging to four families and twelve species HRM-PCR correctly identified specimens belonging to three families and eight species.     

A brief history of forensic entomology.

Apart from an early case report from China (13th century) and later artistic contributions, the first observations on insects and other arthropods as forensic indicators were documented in Germany and France during mass exhumations in the late 1880s by Reinhard and Hofmann, whom we propose recognizing as co-founders of the discipline. After the French publication of Mégnin's popular book on the applied aspects of forensic entomology, the concept quickly spread to Canada and the US. At the time, researchers recognized that the lack of systematic observations of forensically important insects stood in the way of their use as indicators of postmortem interval. General advances in insect taxonomy, and ecology helped close this gap over the following decades.Many early case reports dealt with alleged child homicides, including the suspected use of sulphuric acid. In this context, it was shown that ants, cockroaches, and freshwater arthropods could produce postmortem artifacts suggestive of child abuse.After the World Wars, few forensic entomology cases entered the scientific literature. From the 1960s to the 1980s, Leclecq and Nuorteva were primarily responsible for maintaining the method in Central Europe, with a focus on case work. Since then, basic research in the US, Russia and Canada has opened the way to the routine use of entomology in forensic investigations. The following article gives a brief overview of historic developments in the field. A major focus is on the work done between 1850 and 1950. Since sources from that time remain difficult to track down, the article also includes a historic bibliographical overview on forensic entomology of that era.     

近十年来我国现代法医昆虫学研究进展

法医昆虫学(Forensic entomology)指的是应用昆虫学知识解决法律上问题的法医学分支学科,在死后间隔时间判断,特别是腐败尸体的死后间隔时间判断等方面有著无可比拟的优越性。本文讨论了法医昆虫学的研究领域,从理论研究与实践应用两方面概述了近十年来法医昆虫学在我国的进展。     

尸源性昆虫的法医学研究进展

尸源性昆虫学是应用昆虫学知识解决有关法律问题的法医学分支学科,对死亡时间的推断。特别是腐败尸体的死后间隔时间的推断等方面具有无可比拟的优越性。本文根据国内外近期法医昆虫学方面的研究进展,阐述了尸源性昆虫的研究历史、种类和侵蚀过程,并总结了尸源性昆虫形态学及分子生物学的种属鉴定方法。及近几年来在推断死亡时间方面的具体应用。就尸源性昆虫在法医学领域内的应用及进展进行综述。     

Wildlife forensic entomology: determining time of death in two illegally killed black bear cubs.

Forensic entomology is now commonly used to determine time of death in human death investigations. However, it can be equally applicable to wildlife crimes. This paper describes the use of entomology to determine time of death in the illegal killing of two young bear cubs in Manitoba, Canada. Two cubs were found shot, disemboweled, with their gall bladders removed. Natural Resource officers (Conservation Officers) and a Royal Canadian Mounted Police (R.C.M.P.) officer examined the remains, and the R.C.M.P. officer collected insect evidence. The only insects on the remains were adult blow flies coming to lay eggs and the blow fly eggs themselves (Diptera: Calliphoridae). The time of hatch was recorded and the insects were reared to adulthood. Time of hatch, together with species identification, macro and micro climate and lab developmental data were used to determine the time of death. The time was consistent with the time that the defendants were seen at the scene and was used in their conviction. This case illustrates that insect evidence can be equally as valuable in poaching cases as in homicide cases. However, in most cases Conservation Officers are unaware of this science. It is therefore, extremely important for more Conservation Officers to be educated about this field.     

Turf wars: authority and responsibility for the investigation of mass graves

Mass graves are complex products of large-scale crimes. Such scenes pose four conceptual challenges to investigators and forensic experts: the individual victim, the crime, the setting, and the statistical. Exhumation and post-mortem examination of mortal remains with associated personal and forensic evidence require integrated management of core forensic personnel including investigators, archaeologists, anthropologists, odontologists and pathologists, among whom there is overlapping expertise. The key to avoiding competition and ill-will among experts is to recognize that all such experts should be enabled to make known how their expertise matches with the temporal and spatial boundaries of victim, crime and setting. In turn, they should be apprised of where they fit into the overall judicial process and their limits within the investigation. Consequently, each expert requires access to the factual background of the case, to the site and its contents throughout the investigation. Each forensic team member has a responsibility to influence the investigation--throughout its course when possible--to make findings within their areas of expertise, and to make these available to the rest of the team so as to contribute most meaningfully to the aims of the investigation, both forensic and humanitarian. The on-site crime scene manager has an overarching role to enable integrated access to the complete scene and its contents by each forensic expert team member. In other words, the forensic scientist is given access and the ability to influence the investigation while control of evidence from the site as to identity and criminal activity are maintained by the crime scene manager. This contribution is directed at both the crime scene manager and each forensic expert; it describes the essential spatial and temporal parameters of an expert's opinion so as to encourage cooperation, and discourage conflict, within the forensic team.     

Hate crimes and the forensic pathologist

Hate crimes represent crimes committed against an individual or group on the basis of their race, ethnicity, national origin, religion, sexual orientation, gender, gender identity, or disability. For the forensic pathologist, a death related to a hate crime should be considered a high-profile case, one in which the pathologist should expect abundant public interest and scrutiny. In this article, an overview of hate crimes is presented, stressing the different types of hate crimes and the motives of those who commit such crimes. For death investigators and forensic pathologists, an awareness of these details will help them to recognize and appropriately anticipate issues that may be important in deaths related to hate crimes.     

Maggot development during morgue storage and its effect on estimating the post-mortem interval

When insect evidence is obtained during autopsy, forensic entomologists make decisions regarding the effects of low-temperature (-1 degrees C to 4 degrees C) storage of the body and associated insects when estimating the post-mortem interval (PMI). To determine the effects of storage in a morgue cooler on the temperature of maggot masses, temperatures inside and outside of body bags containing a human cadaver and porcine cadavers (seven replicates) were measured during storage. Temperatures remained significantly higher (p<0.05) inside of the body bags relative to the cooler, and remained at levels sufficient for maggot feeding and development. If the assumption that no insect development takes place during preautopsy refrigeration is made, potential error rates in PMI estimation of 8.6-12.8% occur. The potential for blow fly larvae to undergo significant development while being stored in the morgue is a possibility that forensic entomologists should consider during an investigation involving samples collected from autopsy. Case and experimental evidence also demonstrate that substantial tissue loss can occur from maggot feeding during morgue storage.     

新冠肺炎疫情期间公安法医应当加强尸体甄别和个体防护

因鉴定体制特点,公安法医除参与尸体有关的现场勘查工作外,还需进行尸体检验工作。在此过程中,可能面对很多风险,受伤和中毒等事件时有发生。然而,国内公安法医对新冠肺炎等传染病流行期间死亡的尸体如何甄别进行尸体检验鉴定,对现场勘查及尸体检验工作的防护只有少量规定,且内容不够详尽。本文对法医在现场勘查中遇到的尸体及尸体检验中实验室建设、职业现状、风险评估及防范措施等进行了论述。最后,建议出台相关的制度规定等具体约束规范措施,以保障公安法医现场勘查及尸体检验工作的顺利进行,以解除基层鉴定机构和鉴定人的后顾之忧。     

广东省室内、室外及中毒死亡案件中法医昆虫学的应用报道

基于昆虫的死亡时间推断是目前最为有效和最准确的方法,本文介绍了广东省4例应用昆虫准确判断死亡时间的案例,这些案例分别发生于3月、5月和6月,现场包括室外现场和室内现场,尸体类型包括死亡不久的尸体和高度腐败的尸体,死亡原因包括钝器窒息、锐器致死、勒颈致死及过量药物中毒致死,其中过量药物中毒致死的案例由于体内含有49倍致死剂量的氯氮平从而使昆虫的发育受到严重影响进一步使得死亡时间推断时间结果比真实时间短。     

An alternative for the extraction and storage of DNA from insects in forensic entomology

An important area of recent research in forensic entomology has been the use of insect DNA to provide identification of insects for fast and accurate estimation of time since death. This requires DNA to be extracted efficiently and in a state suitable for use in molecular procedures, and then stored on a long-term basis. In this study, Whatman FTA cards were tested for use with the Calliphoridae (Diptera). In particular, testing examined their ability to effectively extract DNA from specimens, and store and provide DNA template in a suitable condition for amplification using the polymerase chain reaction (PCR). The cards provided DNA that was able to be amplified from a variety of life stages, and thus appears to be of sufficient quality and quantity for use in subsequent procedures. FTA cards therefore appear suitable for use with calliphorids, and provide a new method of extraction that is simple and efficient and allows for storage and transportation without refrigeration, consequently simplifying the handling of DNA in forensic entomological cases.     

Independent forensic autopsies in an armed conflict: investigation of the victims from Racak, Kosovo

In January 1999, a team of Finnish forensic experts under the mandate of the European Union (EU forensic expert team, EU-FET) performed forensic investigations in a sovereign state, in Kosovo, the Federal Republic of Yugoslavia (FRY). The team served as a neutral participant in the forensic investigation of victims of an incident at Racak, which was receiving considerable international attention. The Finnish team performed forensic autopsies, monitored forensic autopsies performed by local experts and verified findings of earlier executed autopsies. The victims had sustained varying numbers of gunshot wounds, which were established to be the cause of death. The manner of death remained undetermined by the EU-FET, because the scene investigation and the chain of custody for the bodies from the site of the incident to the autopsy were impossible to verify by the team. The events at Racak were the first of those leading to charges by the International Criminal Tribunal for the former Yugoslavia (ICTY) against the highest authorities in power in the FRY for crimes against humanity and violations of the laws or customs of war.     

Importance and Approach to Manner of Death Opinions in Opioid-Related Deaths

The majority of opioid-related deaths are accidental. However, the number of opioid-related suicidal deaths is likely under recognized. Presented here is a case of suicide by heroin overdose. The manner of death would have likely been deemed accidental if not for critical information shared by the decedent’s family during follow-up telephone interviews between the forensic pathologist and the decedent’s family, which included text messages that were sent by the decedent just before his death that were not known at the time of the initial medicolegal death scene investigation. This case highlights that when a forensic pathologist establishes an engaged relationship with the decedent’s family, the information elucidated can prove to be invaluable in reaching an informed opinion about the manner of death. For overdose cases, identifying an accurate manner of death allows the design of public health efforts that adequately address the health risks in the community. For aid in the determination of the manner of death for overdose cases, we propose a five-step checklist that may assist forensic pathologists and medicolegal death investigators when approaching similar cases.     

A Forensic Entomological Analysis Can Yield an Estimate of Postmortem Interval,and Not Just a Minimum Postmortem Interval: An Explanation and Illustration Using a Case

Several authors claimed that a forensic entomological analysis can never be interpreted as the postmortem interval (PMI), but that it can be interpreted as a minimum postmortem interval (PMI_min), or dead for not less than X amount of time. Because in most instances, a PMI estimate should be a range, that is, the set of values from maximum postmortem interval (PMI_max) to PMI_min, objections to PMI estimation are objections to PMI_max estimation. The arguments for this position did not address the substantial body of literature describing estimation of both PMI_max and PMI_min using insect succession analysis. This report reviews the scientific issues and presents a recent homicide investigation in which several forensic entomology experts used the absence of carrion insects on the corpse, a kind of succession analysis, to estimate PMI or PMI_max.     

Evaluation of sudden death in psychiatric patients with special reference to phenothiazine therapy: forensic pathology

The investigation of sudden unexpected death in psychiatric patients and the ensuing litigation has brought to our attention many unusual features important in the evaluation of such deaths. Certain pathophysiologic mechanisms of death, rarely encountered in routine forensic science practice, may be important in determining the cause of death in psychiatric patients, especially in cases where the autopsy is unrevealing. Of particular concern is a tendency in the current literature to implicate phenothiazines as a cause of death when the death investigation and the autopsies are incomplete. Thus, based on our experience and on a review of the current literature, we have set forth factors that the forensic pathologist should consider when faced with a sudden psychiatric death. A case report illustrates these unique aspects of scene investigation and analysis of terminal events and autopsy findings.     

An experimental field protocol for investigating the postmortem interval using multidisciplinary indicators

This article proposes an experimental field protocol for investigating the postmortem interval using specially designed apparatus and human and pig cadavers. We further propose that this goal can only be achieved by a multidisciplinary group, comprised of forensic entomologists, pathologists, and anthropologists. The apparatus and collecting methods described by the authors establish the means by which data can be collected on several fronts simultaneously: the sequential arrival and variety of insects in the decay process, the character and manner of soft tissue decomposition, the sequence and nature of bone exposure and order of disarticulation of skeletal remains, and the influence of climate and season on decay rates and arthropod succession. A central feature of this protocol involves the construction and use of a dual-functioning insect trap that allows separate but simultaneous capture of arriving and emerging populations while successional and decompositional processes of the cadaver are left intact. Results of trap performance tests in an arid climate and preliminary arthropod data collected from field-exposed pig carcasses are presented. The use of this protocol could provide important and badly needed baseline data for both medical investigators and law enforcement personnel, information that is critical to understanding the causes, manner, and time of death, which the law requires to be ascertained.     

Sudden epilepsy deaths and the forensic pathologist

Sudden unexpected deaths in epileptic persons are not rare events, most commonly encountered by the forensic pathologist rather than the clinician. Such deaths may represent 1-1.5% of all "natural" deaths certified by the medical examiner or coroner. The typical victim is a black male about 30 years of age who tends to abuse alcohol, with a history of generalized epilepsy for more than 1 year and likely for more than 10 years. There are a lack of obvious anatomic causes for the death at autopsy, but 60-70% of cases will have a lesion in the brain (most commonly old trauma) to explain the epilepsy. Most victims have no blood levels of anticonvulsant medications at the time of death. We have evolved a form for use by medical examiner/coroner's investigators at the scene to collect relevant information which will be of assistance to the pathologist in interpreting the case. Estimated prevalence of sudden epilepsy death, mechanisms, and other features of such cases are reviewed briefly.