Refine
Document Type
- Article (25)
Has Fulltext
- yes (25) (remove)
Is part of the Bibliography
- no (25)
Keywords
- Autopsy (5)
- Age estimation (2)
- Biological profile (2)
- Blow flies (2)
- COVID-19 (2)
- Erweiterter Suizid (2)
- Extended suicide (2)
- Forensic medicine (2)
- Gemeinschaftliche Selbsttötung (2)
- Molecular autopsy (2)
Institute
Justification: In Mexico, the number of unidentified bodies has been steadily rising for years. By now, more than 50,000 bodies are considered unidentified. Forensic laboratories that could perform comparative molecular genetic investigation are often overburdened and examinations can take months. Therefore, pragmatic approaches that can help to identify more unknown bodies must be sought. The increased use of distinctive physical features might be one, and the high rate of tattooed people in Mexico points towards a great potential of tattoos as a tool for identification. The prerequisite for a comparison of antemortem (missing persons) and postmortem (unknown bodies) data is an objective description of the particularities, e.g., of the tattoos. The aim of this study was to establish an objective classification for tattoo motives, taking into consideration local preferences.
Methods: In the database of the medicolegal services of the Instituto Jaliscience de Ciencias Forenses (IJCF) in Guadalajara, postmortem data of 1000 tattooed bodies from 2019 were evaluated. According to sex and age, the tattooed body localization and the tattoo motives were categorized.
Results: The 1000 tattooed deceased showed tattoos on 2342 body localizations. The motives were grouped and linked to the following 11 keywords (with decreasing frequency): letters/numbers, human, symbol (other), plant, symbol (religious), animal, object, fantasy/demon/comic, tribal/ornament/geometry, other, unrecognizable.
Conclusion: Using the proposed classification, tattoo motives can be described objectively and classified in a practical way. If used for antemortem (missing persons) and postmortem (unknown bodies) documentation, motives can be searched and compared efficiently—helping to identify unknown bodies.
Estimating the age of the developmental stages of the blow fly Calliphora vicina (Diptera: Calliphoridae) is of forensic relevance for the determination of the minimum post-mortem interval (PMImin). Fly eggs and larvae can be aged using anatomical and morphological characters and their modification during development. However, such methods can only hardly be applied for aging fly pupae. Previous study described age estimation of C. vicina pupae using gene expression, but just when reared at constant temperatures, but fluctuating temperatures represent a more realistic scenario at a crime scene. Therefore, age-dependent gene expression of C. vicina pupae were compared at 3 fluctuating and 3 constant temperatures, the latter representing the mean values of the fluctuating profiles. The chosen marker genes showed uniform expression patterns during metamorphosis of C. vicina pupae bred at different temperature conditions (constant or fluctuating) but the same mean temperature (e.g. constant 10 °C vs. fluctuating 5–15 °C). We present an R-based statistical tool, which enables estimation of the age of the examined pupa based on the analysed gene expression data.
The aim of the current study was to analyze two major pitfalls in forensic entomological casework: delayed evidence sampling and the effect of low-temperature storage of the body. For this purpose, temperature profiles of heavily infested corpses during cooling and cases in which insect evidence was collected both at the scene and during autopsy were evaluated with regard to species composition and development stages found. The results show that the temperature in the body bags remained at higher average temperatures up to 10 °C relative to the mortuary cooler, therefore, sufficient for larval development, with significant differences in temperature between larval aggregations on one and the same body. In addition, we found large differences both in species number, species composition, and the developmental stages found at the scene and during the autopsy. These data and observations underscore the importance of sampling evidence at the scene and recording temperatures throughout the cooling period of a body.
Particulate matter emitted during autopsies can serve as a vector for numerous viruses or bacteria and can lead to infections. Reducing the exposure of those particles in indoor working environments is, therefore, an important issue. To assess the health risk for employees in forensic medicine, we measure particulate matter in the ambient air during autopsies by using an aerosol spectrometer. The autopsies were performed with either an ordinary oscillating saw or an adapted saw with a suction unit. The particle emissions from both saws were compared to each other in order to evaluate whether a technical adaption leads to a particle reduction. Furthermore, the particle exposure reduction by wearing a face mask and variations in the background concentration in the room were analyzed. High particle concentrations were measured while using the ordinary saw. By using the adapted saw or wearing a face mask, the particle exposure could mostly be avoided. On the majority of the working days, an increase in the background concentration could be observed. Based on this knowledge, the use of a proper suction unit and wearing a face mask during autopsies is necessary. Besides, it is important to have sufficient ventilation in the room so that long-lasting high background concentrations can be prevented.
Over the past years, next-generation sequencing (NGS) technologies revolutionized the possibilities in a broad range of application areas. Also in the field of forensic genetics, NGS continuously gained in importance and attentiveness. A significant number of sudden cardiac deaths (SCD) in the young is due to heritable arrhythmia syndromes emphasizing the need of examining the genetic basis in these cases also with regard to the identification of relatives and/or patients being at risk. As a result, high-throughput methods became of increasing value in molecular autopsy investigations enabling the analysis of a broad spectrum of genes.
Most standard protocols are optimized for high-quality samples and frequently not directly applicable to challenging forensic sample material. In the present study, we intended to examine a comprehensive gene panel associated with SCD and inherited arrhythmogenic disorders. We compared three different hybridization-based library preparation technologies in order to implement a suitable NGS workflow for heterogeneous, forensic as well as diagnostic sample material.
The results obtained indicated, that the Illumina technologies Nextera DNA Flex and TruSeq were compatible with samples exhibiting varying levels of degradation. In comparison, the TruSight method also resulted in good sequencing data, but seemed to be more dependent on DNA integrity. The preparation protocols evaluated in our study are not restricted to molecular autopsy investigations and might be helpful for and transferrable to further forensic research applications.
Einleitung: Begehen zwei Menschen infolge einer gemeinsamen Entscheidung Suizid, wird dies als Doppelsuizid oder gemeinschaftlicher Suizid definiert. Die rechtsmedizinische Begutachtung hängt von den Umständen des konkreten Einzelfalls ab und kann für die rechtliche Würdigung insbesondere bei Konstellationen, bei denen ein Beteiligter überlebt hat, wichtige Hinweise liefern.
Material und Methoden: Für einen 25-Jahres-Zeitraum von 1995 bis 2019 wurden retrospektiv alle Sektionsfälle mit vollendeten und versuchten Doppelsuiziden analysiert und, soweit erhältlich, mit den Ermittlungsakten abgeglichen.
Ergebnisse: Unter den erhobenen 23 Doppelsuizidfällen fanden sich 16 vollendete sowie 7 Fälle mit jeweils einem Überlebenden. In 83 % der Fälle handelte es sich um Ehepaare bzw. eingetragene Lebensgemeinschaften, in 13 % um Personen, die sich zuvor in einer psychiatrischen Einrichtung, und in 4 % um Personen, die sich in einem „Suizidforum“ im Internet kennengelernt hatten. Der Mittelwert des Sterbealters betrug bei den Männern 57,8 und bei den Frauen 63,4 Jahre. In etwa zwei Drittel der Fälle wurden Erkrankungen als vorherrschendes Suizidmotiv angegeben. Als häufigste Methode wurde eine Intoxikation gewählt. Am zweithäufigsten fanden Schusswaffen Anwendung, wobei ausnahmslos der Mann zuerst einen oder mehrere Kopfschüsse auf seine Frau abgab, bevor er sich suizidierte. Der häufigste Sterbe- und Auffindeort war das gemeinsame Bett der Suizidenten.
Diskussion: Im Gegensatz zu Suiziden i. Allg. wurden die Doppelsuizide am häufigsten mittels einer Intoxikation als sogenannte weiche Methode verübt. In Anlehnung an die rechtsmedizinische Literatur werden für einen Doppelsuizid typische Merkmale herausgearbeitet.
Schlussfolgerung: Doppelsuizide stellen seltene Fälle in der rechtsmedizinischen Praxis dar, wobei die Abgrenzung zu einem erweiterten Suizid (Homizid-Suizid) schwierig werden kann und zugleich unabdingbar ist. Hierfür ist eine ganzheitliche Berücksichtigung der Vorgeschichte, der rechtsmedizinisch erhobenen Befunde und der kriminalistischen Umstände erforderlich.
The sudden infant death syndrome (SIDS) is one of the leading causes of postneonatal infant death. It has been shown that there exists a complex relationship between SIDS and inherited cardiac disease. Next-generation sequencing and surveillance of cardiac channelopathy and cardiomyopathy genes represent an important tool for investigating the cause of death in SIDS cases. In the present study, targeted sequencing of 80 genes associated with genetic heart diseases in a cohort of 31 SIDS cases was performed. To determine the spectrum and prevalence of genetic heart disease associated mutations as a potential monogenic basis for SIDS, a stringent variant classification was applied and the percentage of rare (minor allele frequency ≤ 0.2%) and ultra-rare variants (minor allele frequency ≤ 0.005%) in these genes was assessed. With a minor allele frequency of ≤ 0.005%, about 20% of the SIDS cases exhibited a variant of uncertain significance (VUS), but in only 6% of these cases, gene variants proved to be “potentially informative.” The present study shows the importance of careful variant interpretation. Applying stringent criteria misinterpretations are avoided, as the results of genetic analyses may have an important impact of the family members involved.
Bei Suizidformen mit mehreren Suizidenten und Opfern werden teilweise in Literatur und Rechtsprechung eine unterschiedliche Nomenklatur und Interpretation der Begrifflichkeiten vorgenommen. Der Beitrag analysiert die Begrifflichkeiten und befasst sich im Speziellen mit dem Phänomen des Doppelsuizids. Historische Fälle von Doppelsuiziden werden angeführt. Anhand von Fallkonstellationen werden rechtliche Bewertungen vorgenommen, die beim einseitig fehlgeschlagenen Doppelsuizid praxisrelevant werden können. Dabei werden die mitunter konträren Auffassungen in der einschlägigen Literatur und der Rechtsprechung dargestellt und Lösungsansätze aufgezeigt. Zudem verdeutlichen die Fallkonstellationen die Relevanz einer umfassenden Tatortarbeit und einer tatnahen Klärung der Motivationslage bei dem Überlebenden bzw. den Verstorbenen.
The bluebottle blow fly Calliphora vicina is a common species distributed throughout Europe that can play an important role as forensic evidence in crime investigations. Developmental rates of C. vicina from distinct populations from Germany and England were compared under different temperature regimes to explore the use of growth data from different geographical regions for local case work. Wing morphometrics and molecular analysis between these populations were also studied as indicators for biological differences. One colony each of German and English C. vicina were cultured at the Institute of Legal Medicine in Frankfurt, Germany. Three different temperature regimes were applied, two constant (16°C & 25°C) and one variable (17–26°C, room temperature = RT). At seven time points (600, 850, 1200, 1450, 1800, 2050, and 2400 accumulated degree hours), larval lengths were measured; additionally, the durations of the post feeding stage and intrapuparial metamorphosis were recorded. For the morphometric and molecular study, 184 females and 133 males from each C. vicina population (Germany n = 3, England n = 4) were sampled. Right wings were measured based on 19 landmarks and analyzed using canonical variates analysis and discriminant function analysis. DNA was isolated from three legs per specimen (n = 61) using 5% chelex. A 784 bp long fragment of the mitochondrial cytochrome b gene was sequenced; sequences were aligned and phylogenetically analyzed. Similar larval growth rates of C. vicina were found from different geographic populations at different temperatures during the major part of development. Nevertheless, because minor differences were found a wider range of temperatures and sampling more time points should be analyzed to obtain more information relevant for forensic case work. Wing shape variation showed a difference between the German and English populations (P<0.0001). However, separation between the seven German and English populations at the smaller geographic scale remained ambiguous. Molecular phylogenetic analysis by maximum likelihood method could not unambiguously separate the different geographic populations at a national (Germany vs England) or local level.
Determining the age of juvenile blow flies is one of the key tasks of forensic entomology when providing evidence for the minimum post mortem interval. While the age determination of blow fly larvae is well established using morphological parameters, the current study focuses on molecular methods for estimating the age of blow flies during the metamorphosis in the pupal stage, which lasts about half the total juvenile development. It has already been demonstrated in several studies that the intraspecific variance in expression of so far used genes in blow flies is often too high to assign a certain expression level to a distinct age, leading to an inaccurate prediction. To overcome this problem, we previously identified new markers, which show a very sharp age dependent expression course during pupal development of the forensically-important blow fly Calliphora vicina Robineau–Desvoidy 1830 (Diptera: Calliphoridae) by analyzing massive parallel sequencing (MPS) generated transcriptome data. We initially designed and validated two quantitative polymerase chain reaction (qPCR) assays for each of 15 defined pupal ages representing a daily progress during the total pupal development if grown at 17 °C. We also investigated whether the performance of these assays is affected by the ambient temperature, when rearing pupae of C. vicina at three different constant temperatures—namely 17 °C, 20 °C and 25 °C. A temperature dependency of the performance could not be observed, except for one marker. Hence, for each of the defined development landmarks, we can present gene expression profiles of one to two markers defining the mentioned progress in development.