Bertelsenkruse6374

Thiazolidine carboxylates such as thiazolidine-4-carboxylate (T4C) and thiazolidine-2-carboxylate (T2C) are naturally occurring sulfur analogues of proline. These compounds have been observed to have both beneficial and toxic effects in cells. Given that proline dehydrogenase has been proposed to be a key enzyme in the oxidative metabolism of thioprolines, we characterized T4C and T2C as substrates of proline catabolic enzymes using proline utilization A (PutA), which is a bifunctional enzyme with proline dehydrogenase (PRODH) and l-glutamate-γ-semialdehyde dehydrogenase (GSALDH) activities. PutA is shown here to catalyze the FAD-dependent PRODH oxidation of both T4C and T2C with catalytic efficiencies significantly higher than with proline. Stopped-flow experiments also demonstrate that l-T4C and l-T2C reduce PutA-bound FAD at rates faster than proline. Unlike proline, however, oxidation of T4C and T2C does not generate a substrate for NAD+-dependent GSALDH. Instead, PutA/PRODH oxidation of T4C leads to cysteine formation, whereas oxidation of T2C generates an apparently stable Δ4-thiazoline-2-carboxylate species. Our results provide new insights into the metabolism of T2C and T4C.We present a new route for obtaining surface-tethered polymer films containing pendant catechol functional groups via surface-initiated activators regenerated by electron-transfer atom-transfer radical polymerization (SI-ARGET ATRP) of glycidyl methacrylate (GMA) and post-polymerization modification of the resulting poly(glycidyl methacrylate) (pGMA) films with dopamine. This method enables a high degree of functionalization of pGMA films with catechol groups at a controlled level, depending on the duration of the post-polymerization modification reaction. The dopamine-pGMA films readily absorbs Al3+ and Zn2+ ions, as verified by quartz crystal microbalance with dissipation (QCM-D) under continuous flow conditions, and demonstrates a four-fold molar selectivity to Al3+ over Zn2+. The ions desorb from the films upon rinsing with pure deionized (DI) water, which regenerates the catechol sites in the dopamine-pGMA film. Subsequent exposure to metal ions after rinsing steps yields reproducible levels of loading.A density functional theory method was employed to investigate the mechanism of C-O bond activation of butanoic acid substrates bearing the 8-aminoquinoline (AQ) group catalyzed by Pd(OAc)2. The whole reaction consists of five fundamental steps the chelation of substrate A1, the C-H activation step, the C-N coupling step, the protodepalladation step, and the release of the final product. The calculated results indicated that the protodepalladation step is the rate-determining step with a free energy barrier of 24.3 kcal/mol. This theoretical study pointed out that the energy barriers of C-H activation in the presence and absence of AQ are 11.3 and 26.6 kcal/mol, respectively. This is to say that the installation of the AQ directing group is critical to the regioselectivity of C-H activation and the β-O elimination steps, and this reason enables selective activation of the γ C-O bond. Furthermore, this chelating functionality facilitated the protodepalladation step because the energy barrier of the protodepalladation step was decreased with the coordination of the AQ directing group with a Pd center, and that was 39.3 kcal/mol in the absence of AQ. This also explains why no product formation was observed in the experiment upon changing the directing AQ group to a phenylamino group. Finally, other substrates bearing the phenol leaving group at the β- and δ-positions of carbonyl were investigated in order to expand the applicability of the AQ directing strategy. This work could provide new theoretical insights into the activation of strong alkyl C(sp3) covalent bonds via the AQ directing strategy.Surfactants are often added to aqueous solutions to induce spreading on otherwise unwettable hydrophobic surfaces. Alternatively, they can be introduced directly into solid hydrophobic materials─such as the soft elastomer, polydimethylsiloxane─to induce autonomous wetting without requiring additional surface or liquid modifications. Given the similarity between mechanisms of these two approaches, models that describe wetting by aqueous surfactant solutions should also characterize wetting on surfactant-solid systems. To investigate this theory, multiple surfactants of varying size and chemical composition were added to prepolymerized PDMS samples. After cross-linking, water droplets were placed on the surfaces at set time points, and their contact angles were recorded to track the temporal evolution of the interfacial tension. Multiple nonlinear models were fitted to this data, their parameters were analyzed, and each goodness of fit was compared. An empirical model of dynamic surface tension was found to describe the wetting process better than the single established model found in the literature. The proposed model adapted better to the longer time scales induced by slow molecular diffusivity in PDMS. Siloxane ethoxylate surfactants induced faster and more complete wetting of PDMS by water than oxyoctylphenol ethoxylates did. The generalizability of this model for characterizing nonionic surfactants of a wide range of physiochemical properties was demonstrated.Carbohydrate-active enzymes (CAZymes) play critical roles in diverse physiological and pathophysiological processes and are important for a wide range of biotechnology applications. Kinetic measurements offer insight into the activity and substrate specificity of CAZymes, information that is of fundamental interest and supports diverse applications. However, robust and versatile kinetic assays for monitoring the kinetics of intact glycoprotein and glycolipid substrates are lacking. Here, we introduce a simple but quantitative electrospray ionization mass spectrometry (ESI-MS) method for measuring the kinetics of CAZyme reactions involving glycoprotein substrates. The assay, referred to as center-of-mass (CoM) monitoring (CoMMon), relies on continuous (real-time) monitoring of the CoM of an ensemble of glycoprotein substrates and their corresponding CAZyme products. Notably, there is no requirement for calibration curves, internal standards, labeling, or mass spectrum deconvolution. To demonstrate the reliability of CoMMon, we applied the method to the neuraminidase-catalyzed cleavage of N-acetylneuraminic acid (Neu5Ac) residues from a series of glycoproteins of varying molecular weights and degrees of glycosylation. Reaction progress curves and initial rates determined with CoMMon are in good agreement (initial rates within ≤5%) with results obtained, simultaneously, using an isotopically labeled Neu5Ac internal standard, which enabled the time-dependent concentration of released Neu5Ac to be precisely measured. To illustrate the applicability of CoMMon to glycosyltransferase reactions, the assay was used to measure the kinetics of sialylation of a series of asialo-glycoproteins by a human sialyltransferase. Finally, we show how combining CoMMon and the competitive universal proxy receptor assay enables the relative reactivity of glycoprotein substrates to be quantitatively established.While red-backed salamanders (Plethodon cinereus) are most often observed in terrestrial forested areas, several studies report arboreal substrate use and climbing behavior. However, salamanders do not have any of the anatomical features commonly observed in specialized climbing species (e.g., claws, setae, suction cups). Instead, salamanders cling to surfaces using the shear and adhesive properties of their mucous layer. In this study, we explore the capabilities and spatiotemporal gait patterns of arboreal locomotion in the red-backed salamander as they move across twelve substrate conditions ranging in diameter, orientation, and roughness. On arboreal substrates, red-backed salamanders decreased locomotor speed, stride frequency, phase and stride length, and increased duty factor and stride duration. Such responses have been observed in other non-salamander species and are posited to increase arboreal stability. Furthermore, these findings indicate that amphibian locomotion, or at least the locomotor behavior of the red-backed salamander, is not stereotyped and that some locomotor plasticity is possible in response to the demands of the external environment. However, red-backed salamanders were unable to locomote on any small-diameter or vertically-oriented coarse substrates. This finding provides strong evidence that the climbing abilities of red-backed salamanders are attributable solely to mucous adhesion and that this species is unable to produce the necessary external "gripping" forces to achieve fine-branch arboreal locomotion or scale substrates where adhesion is not possible. The red-backed salamander provides an ideal model for arboreal locomotor performance of anatomically-unspecialized amphibians and offers insight into transitionary stages in the evolution of arborealism in this lineage.Ammonium pertechnetate reacts in mixtures of trifluoromethanesulfonic anhydride and trifluoromethanesulfonic acid to ammonium penta-kis(tri-fluoro-methane-sulfonato)oxido-technetate(V), (NH 4 ) 2 [TcO(OTf) 5 ]. The reaction proceeds only at exact concentrations under the exclusion of air and moisture via the formation of pertechnetyl trifluoromethanesulfonate, [TcO 3 (OTf)], and intermediate Tc(VI) species. 99 Tc nuclear magnetic resonance (NMR) has been used to study the Tc(VII) compound and electron paramagnetic resonance (EPR), 99 Tc NMR and X-ray absorption near-edge structure (XANES) experiments indicate the presence of reduced technetium species. Selleck MEK inhibitor (NH 4 ) 2 [TcO(OTf) 5 ] slowly hydrolyses under formation of the tetrameric oxidotechnetate(V) (NH 4 ) 4 [TcO(TcO 4 ) 4 4 ] ⋅ 10 H 2 O. Single crystal X-ray crystallography was used to determine the solid state structures. Ultraviolet-visible (UV-vis) absorption spectroscopy and quantum chemical calculations further confirm the identity of the species.

To address shortages of mental health specialists in low- and middle-income countries, task-shifting approaches have been employed to train nonspecialists to deliver evidence-based scalable psychosocial interventions. Problem Management Plus (PM+) is a brief transdiagnostic nontrauma focused intervention for people affected by adversity. This study reports on the capacity of PM+ to address specific symptoms of posttraumatic stress disorder (PTSD).

Individual patient data from three randomised controlled trials were combined and analysed to observe the impacts of PM+ (n = 738) or enhanced treatment as usual (ETAU) (n = 742) interventions on specific PTSD symptoms at posttreatment and 3-month follow-up. The PTSD-Checklist for DSM-5 (PCL-5) was used to index PTSD symptoms, and presence of each symptom was defined as moderate severity (score ≥ 2 on individual items).

The average PCL-5 score at baseline was 26.1 (SD 16.8) with 463 (31.3%) scoring above 33, indicative of a diagnosis of PTSD. Following intervention, 12.5% and 5.8% of participants retained a score greater than 33 at postassessment and follow-up, respectively. There was greater symptom reduction for PM+ than for ETAU for most symptoms. Hyperarousal symptoms were the most common residual symptoms after PM+, with more than 30% of participants reporting persistent sleep disturbance, concentration difficulties, and anger.

PM+ led to greater reduction in symptoms relating to re-experiencing and avoidance. The evidence indicates that strategies focusing on hyperarousal symptoms including sleep, concentration, and anger difficulties, could be strengthened in this brief intervention.

PM+ led to greater reduction in symptoms relating to re-experiencing and avoidance. The evidence indicates that strategies focusing on hyperarousal symptoms including sleep, concentration, and anger difficulties, could be strengthened in this brief intervention.