Search Results (5)

Background/Objectives: Mitochondrial DNA (mtDNA) analysis is an essential tool for human identification in contexts such as disaster victim identification (DVI) and missing persons cases, where the remains may be highly degraded or even skeletonised. Traditionally, capillary electrophoresis (CE)-based Sanger sequencing has been the standard method for analysing the mtDNA control region. With the development of massively parallel sequencing (MPS) technologies, mtDNA sequencing using MPS offers advantages over traditional Sanger sequencing, such as increased sensitivity, higher throughput, and less sample consumption. The Ion Chef™ and Ion S5™ XL system from Thermo Fisher Scientific represents one such MPS system. Methods: We conducted an internal validation study evaluating key parameters including (a) concordance, repeatability and reproducibility; (b) potential cross-contamination; (c) sensitivity; (d) effects of library pooling on read depth; and (e) mixture sample analysis. Additionally, to mimic samples typically encountered during forensic investigations, case type samples were also used to evaluate the performance of this workflow. While the entire mitochondrial genome was sequenced in this validation study, considering that the international guidelines for full mtDNA genome analysis and interpretation have yet to be fully updated, our analysis, interpretation and subsequent implementation are limited to the control region only. Results: The results obtained demonstrated the reliability, sensitivity and reproducibility of this MPS workflow. Conclusions: This internal validation study supports the implementation of this workflow in our laboratory for the analysis of forensic casework samples. Full article

Introduction: Accurate knowledge of the external carotid artery (ECA) anatomy is essential for head and neck surgery, interventional procedures, and imaging interpretation. Although its branching pattern is classically described as relatively constant, clinically relevant anatomical variations are frequently encountered. Cadaveric dissection remains fundamental for identifying rare vascular configurations. Materials and Methods: During an anatomical teaching dissection of a 72-year-old male cadaver, a right-sided lateral cervicotomy was performed to expose the carotid sheath. After mobilisation of the sternocleidomastoid muscle, the ECA and its proximal branches were skeletonised, allowing detailed three-dimensional assessment of their origin, calibre, and neurovascular relationships. Results: The superior thyroid artery originated from the proximal segment of the external carotid artery, in close proximity to the carotid bifurcation. The main anatomical finding was a lingual artery of relatively small initial calibre exhibiting an atypical superior trajectory: after its origin, it crossed superior to the hypoglossal nerve before continuing toward the tongue. This configuration differs from classical descriptions and modified the anatomical arrangement of Beclard’s and Pirogoff’s triangles, creating a potential site of close neurovascular contact. Conclusions: This cadaveric study describes a rare trajectory-based variant of the external carotid artery characterised by a lingual artery crossing superior to the hypoglossal nerve. Awareness of such rare patterns is essential for improving anatomical interpretation and enhancing surgical safety in the head and neck region. Full article

In clinical diagnostics and longitudinal studies, the reproducibility of MRI assessments is of high importance in order to detect pathological changes, but developments in MRI hard- and software often outrun extended periods of data acquisition and analysis. This could potentially introduce artefactual changes or mask pathological alterations. However, if and how changes of MRI hardware, scanning protocols or preprocessing software affect complex neuroimaging outcomes from, e.g., diffusion weighted imaging (DWI) remains largely understudied. We therefore compared DWI outcomes and artefact severity of 121 healthy participants (age range 19–54 years) who underwent two matched DWI protocols (Siemens product and Center for Magnetic Resonance Research sequence) at two sites (Siemens 3T Magnetom Verio and Skyra^fit). After different preprocessing steps, fractional anisotropy (FA) and mean diffusivity (MD) maps, obtained by tensor fitting, were processed with tract-based spatial statistics (TBSS). Inter-scanner and inter-sequence variability of skeletonised FA values reached up to 5% and differed largely in magnitude and direction across the brain. Skeletonised MD values differed up to 14% between scanners. We here demonstrate that DTI outcome measures strongly depend on imaging site and software, and that these biases vary between brain regions. These regionally inhomogeneous biases may exceed and considerably confound physiological effects such as ageing, highlighting the need to harmonise data acquisition and analysis. Future studies thus need to implement novel strategies to augment neuroimaging data reliability and replicability. Full article

Advances in forensic biology have increased the options for the collection, sampling, preservation and processing of human remains for DNA-based identification. Combined with a plethora of commercial DNA testing kits that are far more forgiving of inhibited and degraded samples, efficient DNA approaches to post-mortem samples are explored here for DNA-based identification of compromised human remains. Approaches which preserve sample and reduce analytical turnaround times whilst saving resources also have the potential to expedite the identification process, to provide answers to grieving families sooner, or to provide leads in a criminal investigation. Targeting sample types that are minimally-invasive and do not require extensive preparation and testing protocols also has benefit for disaster victim identification (DVI) by facilitating field sampling. We have assessed minimally-invasive and simple to collect sample types compatible with minimal pre-treatment and efficient DNA profiling approaches. Incubating nail, distal phalanges and whole digits in 500 µL of PrepFiler™ Lysis Buffer for 2 h was an efficient and simple method, limiting or removing sample preparation. A reduced 15 min incubation also yielded DNA profiles suggesting a shorter incubation may lyse sufficient DNA. Preservative solutions offer an even simpler process in some cases. Furthermore, the efficient approaches described in this study offer storage solutions and are compatible with backend automated processing. This study will inform further research to develop and optimise efficient protocols. These DNA approaches should not be pursued for every sample; more compromised samples may best be submitted to the laboratory for more effective extraction and genotyping. Full article

Forensic anthropological investigations often encounter cases that are difficult to interpret, especially when dealing with skeletal remains found in a marine context. Determining the immersion time in the sea of skeletal remains is a challenge for forensic investigations and answering this would solve many cases in the shortest time possible. The physical and chemical properties of bones change during their time in water and these changes cause difficulties and delays in identifying and reconstructing the biological profile of an unknown subject. In this paper, two forensic cases found at sea were analysed, the case of a disarticulated and extensively skeletonised corpse found on the coast of Reggio Calabria (Italy) and the case of an isolated foot, intact of soft tissues, found only 9 km away, on the coast of Vibo Valentia (Italy). The resolution hypothesis of the two cases was based on three search options because the disappearance of three known individuals was being investigated simultaneously. The investigations were conducted through a multidisciplinary work applying different analyses, including anthropometric, radiological, digital and, finally, genetic analyses. The results made it possible to determine the reconstruction of two biological profiles, both of Case A, the skeletal remain, and Case B, the subject to whom the foot belonged. The almost compatible anthropometric results of the two biological profiles, the presence of two very indicative partial tattoos and a genetic correlation led to the solution of a single court case. Full article