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Quercetin is a natural polyphenolic flavonoid widely found in plants, fruits, and vegetables, and has been reported to play pharmacological roles in numerous pathogenic conditions. The anti-inflammatory effects of quercetin in various inflammatory conditions and diseases have been well-documented. However, its regulatory role in noncanonical inflammasome activation has not yet been demonstrated. This study investigated the anti-inflammatory effects of quercetin in caspase-11 noncanonical inflammasome-activated inflammatory responses in macrophages and a mouse model of acute lethal sepsis. Quercetin protected J774A.1 macrophages from lipopolysaccharide (LPS)-induced cell death and caspase-11 noncanonical inflammasome-induced pyroptosis. It significantly decreased the production and mRNA expression of pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-18, and IL-6, but not tumor necrosis factor (TNF)-α, and inflammatory molecules, such as nitric oxide (NO) and inducible NO synthase in caspase-11 noncanonical inflammasome-activated J774A.1 cells. Mechanistically, quercetin strongly suppressed the autoproteolysis and secretion of caspase-11 and the proteolysis of gasdermin D in caspase-11 noncanonical inflammasome-activated J774A.1 cells. However, quercetin did not inhibit the direct binding of caspase-11 to LPS. In vivo, the study revealed that quercetin increased the survival rate of mice with acute lethal sepsis and decreased serum levels of pro-inflammatory cytokines without causing significant toxicity. In conclusion, this study highlights quercetin-mediated anti-inflammatory action in inflammatory responses and acute lethal sepsis through a novel mechanism that targets the caspase-11 noncanonical inflammasome in macrophages, suggesting quercetin as a promising anti-inflammatory agent in natural medicine. [ABSTRACT FROM AUTHOR]

Turbomachinery in gas turbines uses seals to control the leakage between regions of high and low pressure, consequently enhancing engine efficiency and performance. A film riding seal hybridizes the advantages of contact and non-contact seals, i.e., low leakage and low friction and wear. The literature focuses on the leakage performance of these seals; however, one of their fundamental characteristics, i.e., the gap between the rotor and seal surface, is scarcely presented. The seal pad levitates due to the deflection of the springs at its back under the influence of hydrodynamic forces. This study develops a test rig to measure the levitation of film riding seals. A high-speed motor rotates the rotor and gap sensors measure the levitation of the seal pads. Measurements are also compared with the predictions from a Reynolds equation-based theoretical model. Tests performed for the increasing rotor speed indicated that, initially, until a certain rotor speed, the pads adjust their position, then rub against the rotor until another rotor speed is reached, before finally starting levitating with further increased rotor speeds. Moreover, both the measured and predicted results show that pads levitated the most when located 90° clockwise from the positive horizontal axis (bottom of seal housing) compared to other circumferential positions. [ABSTRACT FROM AUTHOR]

The depletion of the ozone layer over the last four decades has increased Earth's exposure to ultraviolet (UV) radiation, posing significant health risks. Indium‐Gallium‐Zinc‐Oxide (IGZO) phototransistors have emerged as promising UV detection candidates, boasting a wide bandgap (>3 eV), low off‐current, high on‐current, and stability. However, previous efforts to enhance the photoresponse of IGZO phototransistors focused on visible light absorption layers, neglecting UV detection. Here, zinc oxide (ZnO) nanoparticles (NPs) as an absorption layer in IGZO TFTs for UV phototransistors are introduced. IGZO/ZnO TFTs exhibit robust photoresponsivity for UV light below 360 nm, showcasing rejection ratios (Ruv / Rvis) of 20 258, 62 261, 193 649, and 401 582 for wavelengths of 360, 340, 320, and 300 nm, respectively. The combination of IGZO's wide bandgap with ZnO NPs proves effective for detecting UV light below 360 nm, even at low incident light intensities (15 µW cm−2). Enhanced photoresponse characteristics are confirmed via ultraviolet photoelectron spectroscopy. This research highlights the potential of IGZO materials for UV phototransistors and introduces a novel perspective on the utilization of an additional absorption layer traditionally employed for the conventional extension into the visible light range. [ABSTRACT FROM AUTHOR]

In this issue of Structure , Blaimschein et al. elucidate the chaperoning function of the insertase YidC during the insertion and folding of the melibiose permease MelB. Their single-molecule forced unfolding approach reveals that YidC significantly reduces the misfolding and enhances the folding of helices near the interface of two folding cores. [ABSTRACT FROM AUTHOR]