Patient-derived organoid biobank identifies epigenetic dysregulation of intestinal epithelial MHC-I as a novel mechanism in severe Crohn's Disease.

OBJECTIVE: Epigenetic mechanisms, including DNA methylation (DNAm), have been proposed to play a key role in Crohn's disease (CD) pathogenesis. However, the specific cell types and pathways affected as well as their potential impact on disease phenotype and outcome remain unknown. We set out to investigate the role of intestinal epithelial DNAm in CD pathogenesis. DESIGN: We generated 312 intestinal epithelial organoids (IEOs) from mucosal biopsies of 168 patients with CD (n=72), UC (n=23) and healthy controls (n=73). We performed genome-wide molecular profiling including DNAm, bulk as well as single-cell RNA sequencing. Organoids were subjected to gene editing and the functional consequences of DNAm changes evaluated using an organoid-lymphocyte coculture and a nucleotide-binding oligomerisation domain, leucine-rich repeat and CARD domain containing 5 (NLRC5) dextran sulphate sodium (DSS) colitis knock-out mouse model. RESULTS: We identified highly stable, CD-associated loss of DNAm at major histocompatibility complex (MHC) class 1 loci including NLRC5 and cognate gene upregulation. Single-cell RNA sequencing of primary mucosal tissue and IEOs confirmed the role of NLRC5 as transcriptional transactivator in the intestinal epithelium. Increased mucosal MHC-I and NLRC5 expression in adult and paediatric patients with CD was validated in additional cohorts and the functional role of MHC-I highlighted by demonstrating a relative protection from DSS-mediated mucosal inflammation in NLRC5-deficient mice. MHC-I DNAm in IEOs showed a significant correlation with CD disease phenotype and outcomes. Application of machine learning approaches enabled the development of a disease prognostic epigenetic molecular signature. CONCLUSIONS: Our study has identified epigenetically regulated intestinal epithelial MHC-I as a novel mechanism in CD pathogenesis.

Synthesis and Suzuki-Miyaura Cross-Coupling of Alkyl Amine-Boranes. A Boryl Radical-Enabled Strategy.

Alkyl organoborons are powerful materials for the construction of C(sp3)-C(sp2) bonds, predominantly via Suzuki-Miyaura cross-coupling. These species are generally assembled using 2-electron processes that harness the ability of boron reagents to act as both electrophiles and nucleophiles. Herein, we demonstrate an alternative borylation strategy based on the reactivity of amine-ligated boryl radicals. This process features the use of a carboxylic acid containing amine-ligated borane that acts as boryl radical precursor for photoredox oxidation and decarboxylation. The resulting amine-ligated boryl radical undergoes facile addition to styrenes and imines through radical-polar crossover manifolds. This delivers a new class of sp3-organoborons that are stable solids and do not undergo protodeboronation. These novel materials include unprotected α-amino derivatives that are generally unstable. Crucially, these aliphatic organoboron species can be directly engaged in Suzuki-Miyaura cross-couplings with structurally complex aryl halides. Preliminary studies suggest that they enable slow-release of the corresponding and often difficult to handle alkyl boronic acids.

Characterization of Coinfections in Patients with COVID-19.

Background: Little is known about coinfections in patients with COVID-19, with antibiotics often initiated empirically. Objectives: To determine the rates and characteristics of early and late coinfections in COVID-19 patients and to characterize the use of anti-infective agents, especially antibiotics. Methods: This retrospective chart review involved patients with COVID-19 who were admitted to Lions Gate Hospital (Vancouver, British Columbia) between January 1 and June 30, 2020. Data were extracted from electronic medical records, and descriptive statistics were used to analyze the data. Results: Of the 48 patients admitted during the study period, 10 (21%) were determined to have coinfections: 3 (6%) had early coinfections and 7 (15%) had late coinfections. Early empiric use of antibiotics was observed in 32 (67%) patients; for 29 (91%) of these 32 patients, the therapy was deemed inappropriate. Patients with coinfections had longer hospital stays and more complications. Conclusions: Despite low rates of early coinfection, empiric antibiotics were started for a majority of the patients. Most late coinfections occurred in patients in the intensive care unit who required mechanical ventilation. Patients with coinfections had poorer outcomes than those without coinfections.

Contexte: On sait peu de choses sur les co-infections chez les patients atteints de COVID-19, les médicaments antibiotiques étant souvent initiés de manière empirique. Objectifs: Déterminer les taux et les caractéristiques des co-infections précoces et tardives chez les patients atteints de COVID-19 et caractériser l'utilisation d'anti-infectieux, en particulier les antibiotiques. Méthodes: Cet examen rétrospectif des dossiers portait sur des patients atteints de COVID-19 qui ont été admis à l'hôpital Lions Gate, à Vancouver (Colombie-Britannique), entre le 1er janvier et le 30 juin 2020. Les données ont été extraites des dossiers médicaux électroniques et des statistiques descriptives ont été utilisées pour analyser les données. Résultats: Sur les 48 patients admis au cours de la période d'étude, 10 patients (21 %) présentaient des co-infections: 3 patients (6 %) avaient des co-infections précoces et 7 (15 %), des co-infections tardives. Une utilisation empirique précoce d'antibiotiques a été observée chez 32 patients (67 %); pour 29 de ces 32 patients (91 %), le traitement a été jugé inapproprié. Les séjours à l'hôpital des patients co-infectés étaient plus longs et ils présentaient davantage de complications. Conclusions: Malgré de faibles taux de co-infection précoce, des antibiotiques empiriques ont été instaurés pour la majorité des patients. La plupart des co-infections tardives sont survenues chez des patients de l'unité de soins intensifs nécessitant une ventilation mécanique. Les résultats des patients avec co-infections étaient moins bons que ceux sans co-infections.

UK OMFS consultants and trainees strongly support the recommendations of the 2008 Postgraduate Medical Education and Training Board (PMETB) Review of Training in OMFS. The time for delivering them is now.

When the Postgraduate Medical Education and Training Board's (PMETB) Review of Oral and Maxillofacial Surgery (OMFS) Training was published in 2008 it contained five recommendations about OMFS training. As yet, none of these recommendations has been delivered. An online survey was designed to assess awareness of the PMETB review and the current views of OMFS trainees and consultants about its recommendations. Replies were invited using email and social media (WhatsApp, Twitter, and Facebook). As a result of using social media no denominator for the response rate was possible. A total of 304 responses were received, eight of which were anonymous. There was strong support for all the OMFS-specific recommendations: 1: the OMFS specialty should remain a dual medical and dental degree specialty (255, 84%); 2: OMFS training should be shortened (283, 93%); 3: OMFS training should start at the beginning of the second degree (203, 67%); 4: there should be a single medical regulator (General Medical Council) for OMFS (258, 85%); and 6: the need for a second Foundation Year should be removed (260, 86%). Other suggestions about improving OMFS training were also made by participants in the survey. There remains strong support within the specialty for the recommendations of the review. This support is present across consultants, specialty trainees, and those aiming for OMFS specialty training. Some of the original legislative obstructions to delivery of the recommendations have been removed by Brexit creating a unique opportunity for them to be delivered.

United Kingdom oral and maxillofacial surgeons support changes to current specialty recruitment process, which could include 'Walport' style local selection and national benchmarking.

Recruitment to oral and maxillofacial Surgical (OMFS) specialty training was centralised in 2010. The 'flexibility' for OMFS to respond to specialty specific recruitment issues is reducing and many Specialty Trainees' (ST) posts are left unfilled. The National Institute for Health and Care Research (NIHR) appointment process designed to address the problem of recruiting and appointing academic surgeons with local selection with national benchmarking has worked. Using a database of all UK OMFS consultants/trainees, an electronic questionnaire was shared by e-mail, WhatsApp, and other social media. Of 306 replies, 125 (41%) were Consultants/post-certificate of completion training (CCT) individuals, 66 (22%) ST, 61 (20%) second degree students, 27 (9%) pre-second degree, 26 (9%) dual degree pre-ST trainees, and one did not indicate their status. A total of 249 (76%) studied dentistry first and 230 (75%) were male. Of those replying, 147 (48%) had no direct experience of national selection. 120 (39%) had experience as a candidate, 20 (7%) as a selector only, 17 (6%) as a candidate and selector, and two did not record their experience. Of 250 expressing an opinion, 156 (62%) supported local selection with 140 (56%) supporting local selection and national benchmarking, which is a process used for research training posts by the NIHR. Geographical continuity was most important for 78% of pre-second-degree trainees, 45% of STs, and 54% of second-degree students. A total of 57 respondents completed free text comments. There is support for changes in OMFS ST selection including creating OMFS posts which include Foundation and second-degree training in NIHR style locally recruited nationally benchmarked posts.

Developmental Ethanol Exposure Impacts Purkinje Cells but Not Microglia in the Young Adult Cerebellum.

Fetal alcohol spectrum disorders (FASD) caused by developmental ethanol exposure lead to cerebellar impairments, including motor problems, decreased cerebellar weight, and cell death. Alterations in the sole output of the cerebellar cortex, Purkinje cells, and central nervous system immune cells, microglia, have been reported in animal models of FASD. To determine how developmental ethanol exposure affects adult cerebellar microglia and Purkinje cells, we used a human third-trimester binge exposure model in which mice received ethanol or saline from postnatal (P) days 4-9. In adolescence, cerebellar cranial windows were implanted and mice were aged to young adulthood for examination of microglia and Purkinje cells in vivo with two-photon imaging or in fixed tissue. Ethanol had no effect on microglia density, morphology, dynamics, or injury response. However, Purkinje cell linear frequency was reduced by ethanol. Microglia-Purkinje cell interactions in the Purkinje Cell Layer were altered in females compared to males. Overall, developmental ethanol exposure had few effects on cerebellar microglia in young adulthood and Purkinje cells appeared to be more susceptible to its effects.

An air- and moisture-stable ruthenium precatalyst for diverse reactivity.

Versatile, efficient and robust (pre)catalysts are pivotal in accelerating the discovery and optimization of chemical reactions, shaping diverse synthetic fields such as cross-coupling, C-H functionalization and polymer chemistry. Yet, their scarcity in certain domains has hindered the advancement and adoption of new applications. Here we present a highly reactive air- and moisture-stable ruthenium precatalyst [(tBuCN)5Ru(H2O)](BF4)2, featuring a key exchangeable water ligand. This versatile precatalyst drives an array of transformations, including late-stage C(sp2)-H arylation, primary/secondary alkylation, methylation, hydrogen/deuterium exchange, C(sp3)-H oxidation, alkene isomerization and oxidative cleavage, consistently outperforming conventionally used ruthenium (pre)catalysts. The generality and applicability of this precatalyst is exemplified through the potential for rapid screening and optimization of photocatalytic reactions with a suite of in situ generated ruthenium photocatalysts containing hitherto unknown complexes, and through the rapid discovery of reactivities previously unreported for ruthenium. The diverse applicability observed is suggestive of a generic platform for reaction simplification and accelerated synthetic discovery that will enable broader applicability and accessibility to state-of-the-art ruthenium catalysis.

A Self-Assembled Multiphasic Thin Film as an Oxygen Electrode for Enhanced Durability in Reversible Solid Oxide Cells.

The implementation of nanocomposite materials as electrode layers represents a potential turning point for next-generation of solid oxide cells in order to reduce the use of critical raw materials. However, the substitution of bulk electrode materials by thin films is still under debate especially due to the uncertainty about their performance and stability under operando conditions, which restricts their use in real applications. In this work, we propose a multiphase nanocomposite characterized by a highly disordered microstructure and high cationic intermixing as a result from thin-film self-assembly of a perovskite-based mixed ionic-electronic conductor (lanthanum strontium cobaltite) and a fluorite-based pure ionic conductor (samarium-doped ceria) as an oxygen electrode for reversible solid oxide cells. Electrochemical characterization shows remarkable oxygen reduction reaction (fuel cell mode) and oxygen evolution activity (electrolysis mode) in comparison with state-of-the-art bulk electrodes, combined with outstanding long-term stability at operational temperatures of 700 °C. The disordered nanostructure was implemented as a standalone oxygen electrode on commercial anode-supported cells, resulting in high electrical output in fuel cell and electrolysis mode for active layer thicknesses of only 200 nm (>95% decrease in critical raw materials with respect to conventional cathodes). The cell was operated for over 300 h in fuel cell mode displaying excellent stability. Our findings unlock the hidden potential of advanced thin-film technologies for obtaining high-performance disordered electrodes based on nanocomposite self-assembly combining long durability and minimized use of critical raw materials.