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Jens Amendt

Publications and source records attributed to Jens Amendt.

6 recordsLinked to original sources

Best practice in forensic entomology--standards and guidelines.

Forensic entomology, the use of insects and other arthropods in forensic investigations, is becoming increasingly more important in such investigations. To ensure its optimal use by a diverse group of professionals including pathologists, entomologists and police officers, a common frame of guidelines and standards is essential. Therefore, the European Association for Forensic Entomology has developed a protocol document for best practice in forensic entomology, which includes an overview of equipment used for collection of entomological evidence and a detailed description of the methods applied. Together with the definitions of key terms and a short introduction to the most important methods for the estimation of the minimum postmortem interval, the present paper aims to encourage a high level of competency in the field of forensic entomology.

Animals↗

Genetic identification of forensically important flesh flies (Diptera: Sarcophagidae).

Unequivocal identification of fly specimens is an essential requirement in forensic entomology. However, not all species can be determined at every developmental stage, which is illustrated by the flesh flies (Diptera: Sarcophagidae), important members of the necrophagous insect fauna. Up to now no suitable key for the identification of the immature stages of this family of flies exists. DNA analysis of selected mitochondrial genes was applied to solve this problem. Sequence data of selected regions of the CO I and ND 5 genes of the most important European flesh fly taxa associated with cadavers are presented, which can act as reference standards for species determination.

Animals↗

Forensic entomology.

Necrophagous insects are important in the decomposition of cadavers. The close association between insects and corpses and the use of insects in medicocriminal investigations is the subject of forensic entomology. The present paper reviews the historical background of this discipline, important postmortem processes, and discusses the scientific basis underlying attempts to determine the time interval since death. Using medical techniques, such as the measurement of body temperature or analysing livor and rigor mortis, time since death can only be accurately measured for the first two or three days after death. In contrast, by calculating the age of immature insect stages feeding on a corpse and analysing the necrophagous species present, postmortem intervals from the first day to several weeks can be estimated. These entomological methods may be hampered by difficulties associated with species identification, but modern DNA techniques are contributing to the rapid and authoritative identification of necrophagous insects. Other uses of entomological data include the toxicological examination of necrophagous larvae from a corpse to identify and estimate drugs and toxicants ingested by the person when alive and the proof of possible postmortem manipulations. Forensic entomology may even help in investigations dealing with people who are alive but in need of care, by revealing information about cases of neglect.

Animals↗

STR typing of human DNA from fly larvae fed on decomposing bodies.

In homicides with entomological evidence, it may be important to prove the presumed association of fly larvae to a corpse, especially if it is in doubt whether all maggots used for entomological expertise developed and fed on it. The present study demonstrates for the first time the possibility of analyzing human microsatellite DNA present in the digestive tract of necrophagous larvae that fed on decomposed bodies with a postmortem interval up to four months. The obtained human STR profiles support the association of a maggot to a specific corpse. In addition, the identification of the host species (e.g., animal source like pig) can be achieved by analysis of the cytochrome b gene. Maggots were collected from 13 corpses after various postmortem intervals and STR typing and HVR amplifications were performed using their crop contents. In seven cases, a complete STR profile was established, in two cases, an incomplete set of alleles was obtained, and in four cases, STR typing was not successful. HVR analysis was successful in all cases except one. The time of storage of the maggots and the length of the postmortem interval up to 16 weeks appeared to have no particular influence on the quality of the results.

Animals↗

A fatal search for worms--a peculiar electrical accident.

A 32-year-old man used a self-made electrical instrument to collect earthworms for fishing. It consisted of a metal stick with a plastic handle. The stick was connected to a 10 m long wire which ended in a single-phase plug. After watering the lawn and connecting the plug to one phase of a socket (AC 220 V), he touched both the handle and the metal stick, presumably while trying to push it deeper into the soil. Through this procedure he closed the electrical circuit from his left hand to his bare feet standing on the wet lawn and was killed instantly. The autopsy revealed burn marks only on the left palm. Petechiae were found in the facial skin and the mucous membranes. The inner organs showed intensive signs of blood congestion. Toxicological analysis of blood, urine, gastric contents, liver and bile was negative. The calculated current of about 111 mA flowing through the body exceeded the range of 80-100 mA generally considered to be lethal.

Accidents↗

[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.

Adult↗