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Introduction: Postmortem computed tomography (pmCT) prior to forensic autopsy has become increasingly important in recent decades, especially in forensic documentation of single injuries, injury patterns, and causes of death. Postmortem decomposition gas formation can also be detected in pmCT scans, which might affect cochlear implant research in postmortem human temporal bones (TBs)., Material and Methods: Fifty non-putrefied hanging fatalities within a 2-year period (January 2017 to December 2019) were included with 100 TBs. Each body underwent whole-body pmCT prior to forensic autopsy. PmCT scans were analyzed with respect to the presence of intracochlear gas despite the lack of putrefaction at autopsy by an experienced fellow neurotologist., Results: PmCT revealed gas formation in two individuals despite the lack of head trauma and putrefaction at postmortem examination and autopsy. Both individuals showed enclosed gas in the vestibule and the cochlea on both sides., Discussion: Intracochlear gas formation, most likely related to decomposition, may occur despite the lack of putrefaction at postmortem examination and autopsy and can be detected by pmCT. This finding seems to be rather rare in non-traumatic death cases but might affect cochlear pressure research in postmortem human TB., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Mittmann, Ernst, Seidl, Lauer, Gölz, Mutze, Windgassen and Buschmann.)

The newly identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, a pandemic respiratory disease. Moreover, thromboembolic events throughout the body, including in the CNS, have been described. Given the neurological symptoms observed in a large majority of individuals with COVID-19, SARS-CoV-2 penetrance of the CNS is likely. By various means, we demonstrate the presence of SARS-CoV-2 RNA and protein in anatomically distinct regions of the nasopharynx and brain. Furthermore, we describe the morphological changes associated with infection such as thromboembolic ischemic infarction of the CNS and present evidence of SARS-CoV-2 neurotropism. SARS-CoV-2 can enter the nervous system by crossing the neural-mucosal interface in olfactory mucosa, exploiting the close vicinity of olfactory mucosal, endothelial and nervous tissue, including delicate olfactory and sensory nerve endings. Subsequently, SARS-CoV-2 appears to follow neuroanatomical structures, penetrating defined neuroanatomical areas including the primary respiratory and cardiovascular control center in the medulla oblongata.

This article outlines the chronological development of the annual conferences of the German Society of Legal Medicine (DGRM) from 1905 to 2021. The medical and scientific aspects as well as the specific problems of the subject are presented in the context of the respective political and social structures and the conference culture is sketched., (© Springer Medizin Verlag GmbH, ein Teil von Springer Nature 2021.)

Objective: Superior canal dehiscence is defined by missing bony coverage of the superior canal against the middle cranial fossa. The gold standard in diagnosis is high-resolution computed tomography (CT). A false-positive CT scan, identifying a dehiscence when one is not present, could lead to unnecessary surgical therapy. This study aims to compare postmortem CT scans with autopsy findings with regard to superior canal dehiscence., Study Design: Postmortem study., Setting: Tertiary referral center., Subjects and Methods: Twenty-two nontraumatic death cases within a 3-month period (January to March 2017) were included with 44 temporal bones. Each body underwent postmortem head CT prior to medicolegal autopsy. The middle fossa floor was exposed, and if present, the superior semicircular canal dehiscence was identified and measured. In each case, 3 comparable photographs were taken during the autopsy (left temporal bone, right temporal bone, overview)., Results: Autopsy findings revealed bony dehiscences in 11% of the temporal bones, whereas CT scan revealed bony dehiscences in 16%. The length of the dehiscences were longer when measured by CT imaging., Conclusion: The diagnosis of superior canal dehiscence syndrome requires high-resolution CT with clinical symptoms and physiologic evidence of a third mobile window. Our study underlines a mismatch between multislice CT imaging in the coronal plane and the presence of a dehiscence on autopsy.

In eukaryotes, termination of messenger RNA (mRNA) translation is mediated by the release factors eRF1 and eRF3. Using Saccharomyces cerevisiae as a model organism, we have identified a member of the DEAD-box protein (DBP) family, the DEAD-box RNA helicase and mRNA export factor Dbp5, as a player in translation termination. Dbp5 interacts genetically with both release factors and the polyadenlyate-binding protein Pab1. A physical interaction was specifically detected with eRF1. Moreover, we show that the helicase activity of Dbp5 is required for efficient stop-codon recognition, and intact Dbp5 is essential for recruitment of eRF3 into termination complexes. Therefore, Dbp5 controls the eRF3-eRF1 interaction and thus eRF3-mediated downstream events.

A major challenge in current molecular biology is to understand how sequential steps in gene expression are coupled. Recently, much attention has been focused on the linkage of transcription, processing, and mRNA export. Here we describe the cytoplasmic rearrangement for shuttling mRNA binding proteins in Saccharomyces cerevisiae during translation. While the bulk of Hrp1p, Nab2p, or Mex67p is not associated with polysome containing mRNAs, significant amounts of the serine/arginine (SR)-type shuttling mRNA binding proteins Npl3p, Gbp2p, and Hrb1p remain associated with the mRNA-protein complex during translation. Interestingly, a prolonged association of Npl3p with polysome containing mRNAs results in translational defects, indicating that Npl3p can function as a negative translational regulator. Consistent with this idea, a mutation in NPL3 that slows down translation suppresses growth defects caused by the presence of translation inhibitors or a mutation in eIF5A. Moreover, using sucrose density gradient analysis, we provide evidence that the import receptor Mtr10p, but not the SR protein kinase Sky1p, is involved in the timely regulated release of Npl3p from polysome-associated mRNAs. Together, these data shed light onto the transformation of an exporting to a translating mRNP.

Important progress in understanding messenger RNA export from the nucleus could be achieved by increasing the list of proteins that are involved in this process. Here, we present the identification of Gbp2 as a novel shuttling RNA-binding protein in Saccharomyces cerevisiae. Nuclear import of Gbp2 is dependent on the receptor Mtr10 and the serine/arginine-specific protein kinase Sky1. Deletion of the genes encoding both of these proteins or disruption of two of the arginine/serine repeats each shifts the steady-state localization of Gbp2 to the cytoplasm. Interestingly, deletion of MTR10 only also causes an increase in poly(A)(+) RNA binding by Gbp2, suggesting a role of Mtr10 in the dissociation of Gbp2 from mRNA in the cytoplasm. The nuclear export of Gbp2 is always coupled to mRNA export and is dependent on continuous RNA polymerase II transcription and mRNA-export factors. Although GBP2 is not essential for normal cell growth, overexpression of this gene is toxic and causes a nuclear retention of bulk poly(A)(+) RNA. Together, our findings clearly show an involvement of Gbp2 in mRNA transport. In addition, as a non-essential protein, Gbp2 also has the interesting potential to be spatially or temporally regulated.

A rapid and efficient method to inactivate genes in Pseudomonas aeruginosa has been developed. It is based on pKnockout vectors which carry either a gentamicin or a streptomycin/spectinomycin resistance cassette allowing for selection in P. aeruginosa where these vectors do not replicate. A PCR fragment of the gene of interest carrying 5'- and 3'-truncations is cloned into a pKnockout vector, mobilized into P. aeruginosa, and subsequently integrated into the chromosomal copy of the target gene. The orientation of the fragment determines whether (i) the target gene is disrupted without blocking the transcription of downstream genes or (ii) the insertion exerts a polar effect thereby leading to inactivation of a whole operon.