Origins of Catalysis in Non-Heme Fe(II)/2-Oxoglutarate-Dependent Histone Lysine Demethylase KDM4A with Differently Methylated Histone H3 Peptides.

Histone lysine demethylase 4 A (KDM4A), a non-heme Fe(II)/2-oxoglutarate (2OG) dependent oxygenase that catalyzes the demethylation of tri-methylated lysine residues at the 9, 27, and 36 positions of histone H3 (H3 K9me3, H3 K27me3, and H3 K36me3). These methylated residues show contrasting transcriptional roles; therefore, understanding KDM4A's catalytic mechanisms with these substrates is essential to explain the factors that control the different sequence-dependent demethylations. In this study, we use molecular dynamics (MD)-based combined quantum mechanics/molecular mechanics (QM/MM) methods to investigate determinants of KDM4A catalysis with H3 K9me3, H3 K27me3 and H3 K36me3 substrates.

Ambient Noise Levels and Wireless Headsets for Communication in Aerosolizing Otolaryngology Surgery During COVID-19.

The objective of this short scientific communication is to describe and test a strategy to overcome communication barriers in coronavirus disease 2019 (COVID-19) era otolaryngology operating rooms. Thirteen endoscopic sinus surgeries, 4 skull base surgeries, and 1 tracheotomy were performed with powered air-purifying respirators. During these surgeries, surgical team members donned headsets with microphones linked via conference call.

Noise in Endoscopic Sinus and Skull Base Surgery Operating Rooms.

Background: Noise in the operating room (OR) contributes to miscommunication among team members and may negatively impact patient outcomes.

Objectives: This study aimed to quantify noise levels during endoscopic sinus and skull base surgery. The secondary aim was to understand how OR team members perceive noise during endoscopic sinus and skull base surgery.