Chemical tools to define and manipulate interferon-inducible Ubl protease USP18.

Ubiquitin-specific protease 18 (USP18) is a multifunctional cysteine protease primarily responsible for deconjugating the interferon-inducible ubiquitin-like modifier ISG15 from protein substrates. Here, we report the design and synthesis of activity-based probes (ABPs) that incorporate unnatural amino acids into the C-terminal tail of ISG15, enabling the selective detection of USP18 activity over other ISG15 cross-reactive deubiquitinases (DUBs) such as USP5 and USP14. Combined with a ubiquitin-based DUB ABP, the USP18 ABP is employed in a chemoproteomics screening platform to identify and assess inhibitors of DUBs including USP18.

Retrospective Evaluation of Novel Synthetic Opioids and Xylazine Chronic Intake by Post-Mortem Hair Testing.

Fentanyl and its derivatives (nonpharmaceutical fentanyl, NPFs) represent the largest group among synthetic opioids. Fentanyl-related deaths and fatalities from tampering with pharmaceutical products have been reported. Furthermore, in the United States, adulterants such as xylazine and other substances, including the nitazenes class of opioids, have been found in an increasing number of unintentional overdose deaths, drug seizures, and reports of use by recreational drug users.

Scan/rescan reliability of magnetic resonance imaging (MRI).

Background: Magnetic resonance imaging (MRI) is increasingly used to estimate the geometric dimensions of lower lumbar vertebrae. While MRI-based measurements have demonstrated good reliability with interclass correlation coefficients (ICCs) of 0.80 or higher, many evaluations focus solely on the comparison of identical MRI images.