Nonheme iron enzymes utilize = 2 iron(IV)-oxo intermediates as oxidants in biological oxygenations. In contrast, corresponding synthetic nonheme Fe═O complexes characterized to date favor the = 1 ground state that generally shows much poorer oxidative reactivity than their = 2 counterparts. However, one intriguing exception found by Nam a decade ago is the = 1 [Fe(O)(MeNTB)] complex (MeNTB = [tris((-methyl-benzimidazol-2-yl)methyl)amine], ) with a hydrogen atom transfer (HAT) reactivity that is 70% that of the = 2 [Fe(O)(TQA)] complex (TQA = tris(2-quinolylmethyl)amine, ).
View Article and Find Full Text PDFThe synthesis, characterization, and reactivity of a NiOH core bearing a tridentate redox-active ligand capable of reaching three molecular oxidation states is presented in this paper. The reduced complex [LNiOH] was characterized by single-crystal X-ray diffraction analysis, depicting a square-planar NiOH core stabilized by intramolecular H-bonding interactions. Cyclic voltammetry measurements indicated that [LNiOH] can be reversibly oxidized to [LNiOH] and [LNiOH] at very negative reduction potentials (-1.
View Article and Find Full Text PDFIntroduction: Postponement of surgery at preoperative assessment in the days or weeks before the patient is admitted for surgery, as distinct from cancellation on the planned day of surgery, can be devastating for patients and an inefficient use of finite resources. However, postponements are often poorly recorded. The primary aim of this pilot study was to investigate elective surgical postponement rates during or after preoperative assessment across England, and the reasons for postponement for patients on an elective surgical pathway.
View Article and Find Full Text PDFBiodegradable electronic devices play a crucial role in addressing the escalating issue of electronic waste accumulation, which poses significant environmental threats. In this study, we explore the utilization of a methanol-based extract of the plant blended with a carboxymethyl cellulose biopolymer to produce a biodegradable and environmentally friendly functional material for a resistive switching memory system using silver and tungsten electrodes. Our analyses revealed that these two materials chemically interact to generate a perfect composite with near semiconducting optical bandgap (4.
View Article and Find Full Text PDFHerein, we report the first example of Cu-promoted β -hydroxylation of substituted benzophenones using a bidentate directing group (DG) and HO as an oxidant. In addition to the new C-O bond formed, the -oxidation induces a very unusual 1,2-rearrangement of the iminyl group to the vicinal γ position. This transformation is highly dependent on the substrate utilized (favored for 4-methoxy-substituted benzophenones) and on the DG used (2-picolylamine leads to selective γ-C-H functionalization, while β -oxidation requires 2-(2-aminoethyl)pyridine).
View Article and Find Full Text PDFSudden unexpected death in the young (SUDY) is defined as the rapid, unsuspected demise of an apparently healthy individual between the ages of one and 40 years. There is a gap in research pertaining to this population in a South African context. This retrospective study aimed to explore the burden, scope of post-mortem investigation, and risk factors of SUDY admissions to Salt River Mortuary (SRM) in Cape Town between 1 January 2010 and 31 December 2019.
View Article and Find Full Text PDFOrganophosphorus compounds are fundamental for the chemical industry due to their broad applications across multiple sectors, including pharmaceuticals, agrochemicals, and materials science. Despite their high importance, the sustainable and cost-effective synthesis of organophoshoryl derivatives remains very challenging. Here, we report the first successful regio- and stereoselective hydrophosphorylation of terminal allenamides using an affordable copper catalyst system.
View Article and Find Full Text PDFBackground: Monitoring the recovery trajectory during and after hospitalization can be a valuable method to observe whether additional care is needed to optimize recovery. Hand grip strength tests are commonly used to measure an individual's physical condition. Eforto® is a system to monitor hand grip strength and grip work as measures of recovery.
View Article and Find Full Text PDFRedox non-innocent ligands hold the potential to expand the redox chemistry and activity of transition metal catalysts. The impact of the additional redox chemistry of phenol ligands in oxidation catalysis is explored here in the complex μ-oxido-diiron(III) polypyridyl (1) [(L)Fe(III)(μ-O)Fe(III)(L)](ClO) (where HL is 2-(((di(pyridin-2-yl)methyl) (pyridin-2-ylmethyl) amino)methyl)phenol) and its tert-butyl substituted analog 2, in which each of the Fe(III) centers is coordinated to a phenolato moiety of the ligand. Complex 1 was shown earlier to catalyse the oxidation of benzyl alcohols to aldehydes with HO.
View Article and Find Full Text PDFHeparan sulfate (HS) proteoglycans are important regulators of cellular responses to soluble mediators such as chemokines, cytokines and growth factors. We profiled changes in expression of genes encoding HS core proteins, biosynthesis enzymes and modifiers during macrophage polarisation, and found that the most highly regulated gene was Sulf2, an extracellular HS 6-O-sulfatase that was markedly downregulated in response to pro-inflammatory stimuli. We then generated Sulf2 bone marrow chimeric mice and examined inflammatory responses in antigen-induced arthritis, as a model of rheumatoid arthritis.
View Article and Find Full Text PDFUnderstanding the exohedral reactivity of metallofullerenes is crucial for its application in various fields. By systematically controlling the trapped species inside the fullerene its reactivity can be tamed. In this work we report the preferential position of 3d metal atoms inside the C cage and their effect on exohedral reactivity in comparison with the neutral and the dianionic cage.
View Article and Find Full Text PDFCurrent approaches to evaluate molecular complexity use algorithmic complexity, rooted in computer science, and thus are not experimentally measurable. Directly evaluating molecular complexity could be used to study directed vs undirected processes in the creation of molecules, with potential applications in drug discovery, the origin of life, and artificial life. Assembly theory has been developed to quantify the complexity of a molecule by finding the shortest path to construct the molecule from building blocks, revealing its molecular assembly index (MA).
View Article and Find Full Text PDFElectron-coupled-proton buffers (ECPBs) store and deliver protons and electrons in a reversible fashion. We have recently reported an ECPB based on Cu and a redox-active ligand that promoted 4H/4e reversible transformations ( , 144, 16905). Herein, we report a series of Cu-based ECPBs in which the ability of these to accept and/or donate H equivalents can be tuned via ligand modification.
View Article and Find Full Text PDFPrevious studies on bimetallic paddlewheel compounds have established a direct correlation between metal-metal distance and ligand torsion angles, leading to the rule that higher torsion results in longer metal-metal bond distances. Here, the new discovery based on diarylformamidinate Ru₂⁵⁺ paddlewheel compounds [RuCl(DArF)] that show an opposite behavior is reported: higher torsions lead to shorter metal-metal distances. This discovery challenges the assumption that internal rotation solely impacts the δ bond.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
March 2024
TMC- and TMC- the two topological isomers of [Fe(O)(TMC)(CHCN)] (TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane, or Mecyclam), differ in the orientations of their Fe=O units relative to the four methyl groups of the TMC ligand framework. The Fe=O unit of TMC- points away from the four methyl groups, while that of TMC- is surrounded by the methyl groups, resulting in differences in their oxidative reactivities. TMC- reacts with HAT (hydrogen atom transfer) substrates at 1.
View Article and Find Full Text PDFA common neurosurgical condition, chronic subdural haematoma (cSDH) typically affects older people with other underlying health conditions. The care of this potentially vulnerable cohort is often, however, fragmented and suboptimal. In other complex conditions, multidisciplinary guidelines have transformed patient experience and outcomes, but no such framework exists for cSDH.
View Article and Find Full Text PDFThe sharing of health data is an essential component in the provision of healthcare, in medical research, and disease surveillance. Health data sharing is subject to regulatory frameworks that vary across jurisdictions. In Africa, numerous factors complicate the regulation of health data sharing, including technological, motivational, economic, and political barriers, as well as ethical and legal challenges.
View Article and Find Full Text PDFIn 2020 the NHS in England set a target of reaching net zero carbon emissions by 2040. Progress has already been made towards this goal, with substantial reductions in the use of environmentally harmful anaesthetic gases, such as desflurane, in recent years. Where an effective replacement already exists, changing practice to use low carbon alternatives is relatively easy to achieve, but much greater challenges lie ahead.
View Article and Find Full Text PDFSeasonal influenza vaccines must be updated annually and suboptimally protect against strains mismatched to the selected vaccine strains. We previously developed a subunit vaccine antigen consisting of a stabilized trimeric influenza A group 1 hemagglutinin (H1) stem protein that elicits broadly neutralizing antibodies. Here, we further optimized the stability and manufacturability of the H1 stem antigen (H1 stem v2, also known as INFLUENZA G1 mHA) and characterized its formulation and potency with different adjuvants in vitro and in animal models.
View Article and Find Full Text PDFThe capacity to perceived vitality (CPV) ratio is a novel measure for intrinsic capacity or resilience based on grip work and self-perceived fatigue. CPV has been associated with pre-frailty in older adults and post-surgery inflammation in adults. To better understand the utility of this measure in a frail population, we examined the association between CPV and inflammation in geriatric inpatients.
View Article and Find Full Text PDFThe reaction of [(Me/BnTPEN)Ru(NCCH)] (BnTPEN = -benzyl-,,-tris(pyridine-2-ylmethyl)ethane-1,2-diamine and MeTPEN = -methyl-,,-tris(pyridine-2-ylmethyl)ethane-1,2-diamine) with CPBA in the presence of chloride ions in CHCN : HO generated a novel (Me/BnTPEN)Ru-OCl species at room temperature. This hypochlorite adduct could also be obtained by the direct reaction of NaOCl and HClO with (L)Ru complexes. The current study mimics the synthesis of a metal hypochlorite adduct in a similar fashion as in the heme-dependent haloperoxidase enzyme.
View Article and Find Full Text PDFBackground And Objectives: Many people with a psychotic disorder are coping with severe psychosocial limitations related to their illness. The current randomized controlled trial (RCT) investigates the effects of an eating club intervention (HospitalitY (HY)) aimed to improve personal and societal recovery.
Methods: In 15 biweekly sessions participants received individual home-based skill training and guided peer support sessions in groups of three participants from a trained nurse.
Female mosquitoes require blood from their host for egg development. However, the relationship between the composition of host blood and mosquito reproduction, and whether and how this is linked to host selection, remain unclear. A better understanding of these issues is beneficial for mass-rearing of mosquitoes for vector control.
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