COVID-19-Associated Parotitis in a 10-Week-Old Male.

We describe a case of parotitis associated with coronavirus disease 2019 (COVID-19) in a young male infant. His presenting symptom at the time of diagnosis of COVID-19 was unilateral facial swelling. He then developed upper respiratory infection symptoms and proceeded to recover over a period of about a month. Testing for other causes of parotitis was unrevealing. Other cases of COVID-19-associated parotitis have been presented in the literature, but this case is by far the youngest child noted, and is a useful reminder to pediatricians and general practitioners to consider COVID-19 as a cause of parotitis. Additionally, it sheds light on possible transmission and pathophysiology of COVID-19 in the salivary glands, as several other authors have noted.

Correction: Efficient multiplexed genome engineering with a polycistronic tRNA and CRISPR guide-RNA reveals an important role of detonator in reproduction of Drosophila melanogaster.

[This corrects the article DOI: 10.1371/journal.pone.0245454.].

Efficient multiplexed genome engineering with a polycistronic tRNA and CRISPR guide-RNA reveals an important role of detonator in reproduction of Drosophila melanogaster.

Genome association studies in human and genetic studies in mouse implicated members of the transmembrane protein 132 (TMEM132) family in multiple conditions including panic disorder, hearing loss, limb and kidney malformation. However, the presence of five TMEM132 paralogs in mammalian genomes makes it extremely challenging to reveal the full requirement for these proteins in vivo. In contrast, there is only one TMEM132 homolog, detonator (dtn), in the genome of fruit fly Drosophila melanogaster, enabling straightforward research into its in vivo function. In the current study, we generate multiple loss-of-function dtn mutant fly strains through a polycistronic tRNA-gRNA approach, and show that most embryos lacking both maternal and paternal dtn fail to hatch into larvae, indicating an essential role of dtn in Drosophila reproduction.

Shell hardness and compressive strength of the Eastern oyster, Crassostrea virginica, and the Asian oyster, Crassostrea ariakensis.

The valves of oysters act as a physical barrier between tissues and the external environment, thereby protecting the oyster from environmental stress and predation. To better understand differences in shell properties and predation susceptibilities of two physiologically and morphologically similar oysters, Crassostrea virginica and Crassostrea ariakensis, we quantified and compared two mechanical properties of shells: hardness (resistance to irreversible deformation; GPa) and compressive strength (force necessary to produce a crack; N). We found no differences in the hardness values between foliated layers (innermost and outermost foliated layers), age class (C. virginica: 1, 4, 6, 9 years; C. ariakensis: 4, 6 years), or species. This suggests that the foliated layers have similar properties and are likely composed of the same material. The compressive force required to break wet and dry shells was also not different. However, the shells of both six- and nine-year-old C. virginica withstood higher compressive force than C. virginica shells aged either one or four, and the shells of C. ariakensis at both ages studied (4- and 6-years-old). Differences in ability to withstand compressive force are likely explained by differences in thickness and density between age classes and species. Further, we compared the compressive strength of differing ages of these two species to the crushing force of common oyster predators in the Chesapeake Bay. By studying the physical properties of shells, this work may contribute to a better understanding of the mechanical defenses of oysters as well as of their predation vulnerabilities.