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A series of low-cost Lewis acidic deep eutectic solvents (DESs) was synthesized and applied for the first time for catalyzing the polymerization of α-pinene to produce terpene resins. The DES catalyst of [AlCl3]3[CPL] prepared via the self-assembly of AlCl3 and caprolactam (CPL) exhibited the highest catalytic activity, and polymerization conditions were optimized by a single-factor method: 15 g α-pinene, 3 g catalyst, 1 g initiator, −5 °C reaction temperature, and 4 h reaction time. Under these conditions, the softening point of the terpene resin reached (annular spheroid method) 118.3 °C, the acid value was 0.22 mg KOH g−1, and the depth of color (Fe–Co method) was 5. The structure of [AlCl3]3[CPL] was characterized using FT-IR, 1H-NMR, and UV-vis spectroscopy. GPC measure showed that the number-average molecular weight of the terpene resin was 510, the weight-average molecular weight was 776, and the polydispersity index was 1.523. TG results indicated that the terpene resin had favorable thermal stability. After the reaction, the product and the catalyst could be automatically divided into two phases, which was beneficial for recycling the catalyst. The results revealed that [AlCl3]3[CPL] exhibited good recyclability. [ABSTRACT FROM AUTHOR]

Aims: The basolateral amygdala (BLA) plays an integral role in anxiety disorders (such as post traumatic stress disorder) stem from dysregulated fear memory. The excitability of glutamatergic neurons in the BLA correlates with fear memory, and the afterhyperpolarization current (IAHP) mediated by small‐conductance calcium‐activated potassium channel subtype 2 (SK2) dominates the excitability of glutamatergicneurons. This study aimed to explore the effect of MPP2 interacts with SK2 in the excitability of glutamatergic neurons in the BLA and the extinction of conditioned fear in mice. Methods: Fear memory was analyzed via freezing percentage. Western blotting and fluorescence quantitative PCR were used to determine the expression of protein and mRNA respectively. Electrophysiology was employed to measure the excitability of glutamatergic neurons and IAHP. Results: Fear conditioning decreased the levels of synaptic SK2 channels in the BLA, which were restored following fear extinction. Notably, reduced expression of synaptic SK2 channels in the BLA during fear conditioning was caused by the increased activity of protein kinase A (PKA), while increased levels of synaptic SK2 channels in the BLA during fear extinction were mediated by interactions with membrane‐palmitoylated protein 2 (MPP2). Conclusions: Our results revealed that MPP2 interacts with the SK2 channels and rescues the excitability of glutamatergic neurons by increasing the expression of synaptic SK2 channels in the BLA to promote the normalization of anxiety disorders and provide a new direction for the treatment. [ABSTRACT FROM AUTHOR]

Many nanoproteases contain tetravalent metal ions and catalyze peptide‐bond hydrolysis only at high temperature (60 °C). Here, we report a new and effective strategy to explore nanoproteases from nanoparticles containing low valent metal ions. We found that flower‐like CuCoO2 nanoparticles (CuCoO2 NPs) containing low valent Cu+ possessed excellent catalytic activity towards selective cleavage of peptide bonds with hydrophobic residues in bovine serum albumin (BSA) at room temperature. CuCoO2 NPs exhibited excellent stability and had great reusability. CuCoO2 NPs also hydrolyzed heat‐denatured and surfactant‐denatured BSA. Mechanism analysis revealed that the high Lewis acidity of Co3+ and the low valence of Cu+ were both essential for the high protease activity of CuCoO2 NPs. The flower‐like structure of CuCoO2 NPs and the strong nucleophilicity of Cu+‐bound hydroxyl endow them with excellent catalytic performance. The findings open a new way for the design and discovery of high‐efficiency nanoproteases. [ABSTRACT FROM AUTHOR]

Purpose: The STOP-Bang questionnaire is the most widely used to detect surgical patients at high risk of obstructive sleep apnea (OSA). However, the body mass index (BMI) cutoff value in the original STOP-Bang questionnaire is 35 kg/m2; the BMI in the Chinese population is lower than that. We aimed to establish a more appropriate BMI cutoff value in the STOP-Bang questionnaire for Chinese patients.Methods: A total of 790 consecutive patients scheduled to undergo surgery at our hospital were included in this prospective study. All patients were asked to complete the STOP-Bang questionnaire and undergo a 7-h overnight polysomnography (PSG). The ability of STOP-Bang questionnaire to detect moderate to severe OSA (AHI ≥ 15 events/h) was assessed.Results: When the BMI cutoff value was set at 28 kg/m2, the questionnaire had the highest Youden index, although no significant differences were found in the sensitivity of the test compared with the original BMI cutoff in total and in male patients. In females, changing the BMI cutoff value from 35 to 28 kg/m2 resulted in the sensitivity of the test significantly increasing from 79.2% (74.9-83.5) to 89.3% (84.4-94.1), while the decrease in specificity was minor (from 43.6% [41.2-46.0] to 38.2% [36.1-40.3]), and the Youden index was highest (0.27) at this cutoff value. When the STOP-Bang questionnaire score was 4, the highest Youden index was obtained.Conclusions: We recommend using a BMI cutoff value (28 kg/m2), and a STOP-Bang score ≥ 4 allows the anesthetist to identify patients with high risk of OSA. [ABSTRACT FROM AUTHOR]