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The water-based resin impregnates the intercellular areas and generates an artificial compound middle lamella, while the epoxy infiltrates only the cell lumina of the dry DW. Tensile tests in the dry and wet states show that the DMDHEU matrix infiltration of the intercellular areas and the cell wall results in a higher tensile strength and stiffness compared to the epoxy resin. Here, the artificial compound middle lamella made of DMDHEU bonds adjacent fibers together and substantially increases the composites' wet strength. This study elucidates the importance of the interaction and spatial distribution of the resin system within the DW structure to improve mechanical properties, particularly in the wet state.Adult hematopoietic stem cells (HSCs) are predominantly quiescent and can be activated in response to acute stress such as infection or cytotoxic insults. STAT1 is a pivotal downstream mediator of interferon (IFN) signaling and is required for IFN-induced HSC proliferation, but little is known about the role of STAT1 in regulating homeostatic hematopoietic stem/progenitor cells (HSPCs). Here, we show that loss of STAT1 altered the steady state HSPC landscape, impaired HSC function in transplantation assays, delayed blood cell regeneration following myeloablation, and disrupted molecular programs that protect HSCs, including control of quiescence. Our results also reveal STAT1-dependent functional HSC heterogeneity. A previously unrecognized subset of homeostatic HSCs with elevated major histocompatibility complex class II (MHCII) expression (MHCIIhi) displayed molecular features of reduced cycling and apoptosis and was refractory to 5-fluorouracil-induced myeloablation. Conversely, MHCIIlo HSCs displayed increased megakaryocytic potential and were preferentially expanded in CALR mutant mice with thrombocytosis. Similar to mice, high MHCII expression is a feature of human HSCs residing in a deeper quiescent state. Our results therefore position STAT1 at the interface of stem cell heterogeneity and the interplay between stem cells and the adaptive immune system, areas of broad interest in the wider stem cell field.Osteoglycin (OGN) and lipocalin-2 (LCN2) are hormones that can be secreted by bone and have been linked to glucose homeostasis in rodents. However, the endocrine role of these hormones in humans is contradictory and unclear. We examined the effects of exercise and meal ingestion on circulating serum OGN and LCN2 levels in eight healthy males age 28 [25, 30] years [median ± interquartile range (IQR)] and body mass index [BMI] 24.3 [23.6, 25.5] kg/m2. In a randomized crossover design, participants ingested a high-glucose (1.1 g glucose/kg body wt) mixed-nutrient meal (45% carbohydrate, 20% protein, and 35% fat) on a rest-control day and 3 and 24 h after aerobic cycling exercise (1 h at 70%-75% V̇o2peak). Acute aerobic exercise increased serum LCN2 levels immediately after exercise (∼61%), which remained elevated 3-h postexercise (∼55%). In contrast, serum OGN remained similar to baseline levels throughout the 3-h postexercise recovery period. The ingestion of a high-glucose mixed-nutrient meal led to a decrea 24-h postexercise. Findings support that OGN and LCN2 are dynamically linked to energy homeostasis in humans.ERAP1 and ERAP2 are endoplasmic reticulum zinc-binding aminopeptidases that play crucial roles in processing peptides for loading onto class I major histocompatibility complex proteins. These enzymes are therapeutic targets in cancer and autoimmune disorders. The discovery of inhibitors specific to ERAP1 or ERAP2 has been challenging due to the similarity in their active site residues and domain architectures. Here, we identify 4-methoxy-3-[2-piperidin-1-yl-4-(trifluoromethyl) phenyl] sulfamoyl benzoic acid (compound 61) as a novel inhibitor of ERAP2 and determine the crystal structure of ERAP2 bound to compound 61. Compound 61 binds near the catalytic center of ERAP2, at a distinct site from previously known peptidomimetic inhibitors, and inhibits by an uncompetitive mechanism. Surprisingly, for ERAP1, compound 61 was found to activate model substrate hydrolysis, similarly to the previously characterized 5-trifluoromethyl regioisomer of compound 61, known as compound 3. We characterized the specificity determinants of ERAP1 and ERAP2 that control the binding of compounds 3 and 61. At the active site of ERAP1, Lys380 in the S1' pocket is a key determinant for the binding of both compounds 3 and 61. At the allosteric site, ERAP1 binds either compound, leading to the activation of model substrate hydrolysis. Although ERAP2 substrate hydrolysis is not activated by either compound, the mutation of His904 to alanine reveals a cryptic allosteric site that allows for the activation by compound 3. Thus, we have identified selectivity determinants in the active and allosteric sites of ERAP2 that govern the binding of two similar compounds, which potentially could be exploited to develop more potent and specific inhibitors.We describe a new synthetic reaction that generates all-carbon bis-quaternary centers at the opposing side of α-carbons in cyclohexanone with four different substituents in a controlled manner. Catalyzed by Cu(MeCN)4BF4 salt, this chemistry is proposed to proceed via an intermediacy of unsymmetrical O-allyl oxyallyl cations, which undergo a sequence of regioselective nucleophilic addition with substituted indoles and diastereoselective Claisen rearrangement in a single synthetic operation. The stereochemical outcome of the products features the cis diastereorelationship between the two aryl groups at the α,α'-positions.The development of protein-protein interaction (PPI) inhibitors has been a successful strategy in drug development. However, the identification of PPI stabilizers has proven much more challenging. Here we report a fragment-based drug screening approach using the regulatory hub-protein 14-3-3 as a platform for identifying PPI stabilizers. A homogenous time-resolved FRET assay was used to monitor stabilization of 14-3-3/peptide binding using the known interaction partner estrogen receptor alpha. Screening of an in-house fragment library identified fragment 2 (VUF15640) as a putative PPI stabilizer capable of cooperatively stabilizing 14-3-3 PPIs in a cooperative fashion with Fusicoccin-A. Mechanistically, fragment 2 appears to enhance 14-3-3 dimerization leading to increased client-protein binding. Functionally, fragment 2 enhanced potency of 14-3-3 in a cell-free system inhibiting the enzyme activity of the nitrate reductase. In conclusion, we identified a general PPI stabilizer targeting 14-3-3, which could be used as a tool compound for investigating 14-3-3 client protein interactions.The electrochemical nitrate reduction reaction (NITRR), which converts nitrate to ammonia, is promising for artificial ammonia synthesis at mild conditions. However, the lack of favorable electrocatalysts has hampered its large-scale applications. Herein, we report the batch-scale synthesis of three-dimensional (3D) porous Cu@Cu2O microspheres (Cu@Cu2O MSs) composed of fine Cu@Cu2O nanoparticles (NPs) using a convenient electric explosion method with outstanding activity and stability for the electrochemical reduction of nitrate to ammonia. Density functional theory (DFT) calculations revealed that the Cu2O (111) facets could facilitate the formation of *NO3H and *NO2H intermediates and suppress the hydrogen evolution reaction (HER), resulting in high selectivity for the NITRR. Moreover, the 3D porous structure of Cu@Cu2O MSs facilitates electrolyte penetration and increases the localized concentration of reactive species for the NITRR. As expected, the obtained Cu@Cu2O MSs exhibited an ultrahigh NH3 production rate of 327.6 mmol·h-1·g-1cat. (which is superior to that of the Haber-Bosch process with a typical NH3 yield less then 200 mmol h-1g-1cat.), a maximum Faradaic efficiency of 80.57%, and remarkable stability for the NITRR under ambient conditions. Quantitative 15N isotope labeling experiments indicated that the synthesized ammonia originated from the electrochemical reduction of nitrate. Achieving the batch-scale and low-cost production of high-performance Cu@Cu2O MSs electrocatalysts using the electric explosion method is promising for the large-scale realization of selective electrochemical reduction of nitrate toward artificial ammonia synthesis.
The COVID-19 pandemic has drawn attention to various inequalities in global societies, highlighting discrepancies in terms of safety, accessibility, and overall health. In particular, sex workers are disproportionately at risk due to the nature of their work and the social stigma that comes alongside it.
This study examines how public social media can be used as a tool of professional and personal expression by sex workers during the COVID-19 pandemic. We aimed to explore an underresearched topic by focusing on sex workers' experiences with the ongoing COVID-19 pandemic on the social media platform Twitter. In particular, we aimed to find the main issues that sex workers discuss on social media in relation to the COVID-19 pandemic.
A literature review followed by a qualitative analysis of 1458 (re)tweets from 22 sex worker Twitter accounts was used for this study. The tweets were qualitatively coded by theme through the use of intercoder reliability. Empirical, experimental, and observational studies we could recognize the challenges unique to this working community during the COVID-19 pandemic and potentially reduce the widespread stigma associated with sex work in general.
Though there has been an increase in the literature related to the experiences of sex workers, this paper recommends that future studies could benefit from further examining these 5 major categories through mixed methods research. Examining this phenomenon could recognize the challenges unique to this working community during the COVID-19 pandemic and potentially reduce the widespread stigma associated with sex work in general.In this study, we investigated the distribution behavior of single-stranded DNA molecules with 20 bases in silica particles (particle size ∼30 μm) using confocal fluorescence microspectroscopy. The distribution kinetics was investigated under various conditions, such as the type of base (adenine, thymine, guanine, and cytosine), pore size of the particle (30 and 50 nm), and salt concentration (100, 200, and 500 mM), which changed the distribution behavior. At high salt concentrations, we observed sigmoidal kinetic behavior, which does not occur in the general distribution of small organic molecules but is often observed in protein aggregation and nuclear growth. An analytical model based on DNA aggregation explained the sigmoidal distribution behavior well, and this model also worked well when the number of DNA molecules involved in DNA aggregation was greater than two. The intraparticle diffusion of DNA molecules was analyzed using the pore and surface diffusion model. As a result, the intraparticle diffusion of DNA aggregates mainly occurs according to surface diffusion, and the surface diffusion coefficient has the same value ((2.4-6.7) × 10-9 cm2 s-1) independent of the pore size and type of base.