Cu-Promoted Divergent Phosphination of Alkynylsulfonium Salts with Diarylphosphines.

An efficient copper-promoted divergent phosphination of alkynylsulfonium salts with secondary diarylphosphines that tolerates a wide range of functional groups under mild conditions is reported. The use of excess alkynyl dibenzothiophenium salts (/ > 1, mole ratio) enables the phosphination to deliver alkynyl monophosphine products via a C(sp)-P cross-coupling in good to high yields, while the use of excess secondary diarylphosphines (/ < 0.5, mole ratio) leads to a type of -ethenyl bisphosphine products via sequential stereoselective double phosphination.

A comparative analysis reveals the genomic diversity among 8 Muscovy duck populations.

The Muscovy duck (Cairina moschata) is a waterfowl indigenous to the neotropical regions of Central and South America. It has low demand for concentrated feed and strong adaptability to different rearing conditions. After introduced to China through Eurasian commercial trade, Muscovy ducks have a domestication history of around 300 years in the Fujian Province of China.

Multiscale 3D genome organization underlies duck fatty liver with no adipose inflammation or serious injury.

Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease. Little is known about how gene expression and chromatin structure are regulated in NAFLD due to lack of suitable model. Ducks naturally develop fatty liver similar to serious human non-alcoholic fatty liver (NAFL) without adipose inflammation and liver fibrosis, thus serves as a good model for investigating molecular mechanisms of adipose metabolism and anti-inflammation.

Gut microbiota induced abnormal amino acids and their correlation with diabetic retinopathy.

Aim: To explore the correlation of gut microbiota and the metabolites with the progression of diabetic retinopathy (DR) and provide a novel strategy to elucidate the pathological mechanism of DR.

Methods: The fecal samples from 32 type 2 diabetes patients with proliferative retinopathy (PDR), 23 with non-proliferative retinopathy (NPDR), 27 without retinopathy (DM), and 29 from the sex-, age- and BMI- matched healthy controls (29 HC) were analyzed by 16S rDNA gene sequencing. Sixty fecal samples from PDR, DM, and HC groups were assayed by untargeted metabolomics.

Palladium-catalyzed regio- and stereo-selective phosphination of cyclic biarylsulfonium salts to access atropoisomeric phosphines.

A palladium-catalyzed regio- and stereo-selective phosphination of cyclic biarylsulfonium salts (racemic) with HPArAr for straightforward synthesis of atropoisomeric phosphines (P,S-ligands) bearing a stereogenic axis or both a stereogenic axis and a P-stereogenic center is reported. The high reactivity and regio- and stereo-selectivity originate from the torsional strain release and palladium catalysis, and the construction of a P-stereogenic center is enabled by an efficient dynamic kinetic resolution. The high performance of the nascent P,S-ligands has been demonstrated in palladium-catalyzed asymmetric allylic substitutions, indicating the great potential of the present methodology.

Polylactic Glycolic Acid-Mediated Delivery of Plectasin Derivative NZ2114 in Biofilms.

Antimicrobial peptides (AMPs) are antibiotic candidates; however, their instability and protease susceptibility limit clinical applications. In this study, the polylactic acid-glycolic acid (PLGA)-polyvinyl alcohol (PVA) drug delivery system was screened by orthogonal design using the double emulsion-solvent evaporation method. NZ2114 nanoparticles (NZ2114-NPs) displayed favorable physicochemical properties with a particle size of 178.

Genetic and Biological Characteristics of Duck-Origin H4N6 Avian Influenza Virus Isolated in China in 2022.

The interaction between migratory birds and domestic waterfowl facilitates viral co-infections, leading to viral reassortment and the emergence of novel viruses. In 2022, samples were collected from duck farms around Poyang Lake in Jiangxi Province, China, which is located within the East Asia-Australasia flyway. Three strains of H4N6 avian influenza virus (AIV) were isolated.

A new chromosome-scale duck genome shows a major histocompatibility complex with several expanded multigene families.

Background: The duck (Anas platyrhynchos) is one of the principal natural hosts of influenza A virus (IAV), harbors almost all subtypes of IAVs and resists to many IAVs which cause extreme virulence in chicken and human. However, the response of duck's adaptive immune system to IAV infection is poorly characterized due to lack of a detailed gene map of the major histocompatibility complex (MHC).

Results: We herein reported a chromosome-scale Beijing duck assembly by integrating Nanopore, Bionano, and Hi-C data.

Highly Diastereo- and Enantioselective Synthesis of Chiral Cyclohexylphosphines by Cu-Catalyzed Phosphination-Aldol Cyclization of Ketone-Enamides.

A highly diastereo- and enantioselective phosphinative cyclization of ketone-enamides with secondary diarylphosphines enabled by copper catalysis is reported, providing a range of chiral tertiary cyclohexylphosphines bearing three contiguous stereogenic centers in high yields. This asymmetric phosphination-aldol cyclization protocol can also be extended to desymmetrization of dione-enamides to create four contiguous stereogenic centers in a highly selective manner.

Stereoselective Synthesis of Tri- and Tetrasubstituted Allylsilanes via Copper-Catalyzed Decarboxylative Silylation of Vinylethylene Carbonates.

Herein, a stereoselective copper-catalyzed decarboxylative silylation of readily available vinylethylene carbonates (VECs) with PhMeSi-Bpin is reported, affording a wide range of tri- and tetrasubstituted allylsilanes in moderate to high yields with -selectivity. This protocol was characterized by high stereoselectivity, broad substrate scope, operational simplicity, and mild reaction conditions, which were amenable to diverse derivatizations and gram-scale synthesis.

Dithiolation of Alkenyl Sulfonium Salts with Arylthiols to Access 1,2-Dithioalkanes.

A dithiolation of alkenyl sulfonium salts with arylthiols is described, affording a series of 1,2-dithioalkanes in high yields. This protocol features mild and catalyst-free conditions and involves the formation of two C-S bonds sequentially via the regioselective addition of an arylthiol to the unsaturated C═C bonds, followed by the attack of another arylthiol to form 1,2-dithioalkanes exclusively.

Sodium butyrate ameliorates diabetic retinopathy in mice via the regulation of gut microbiota and related short-chain fatty acids.

Background: Diabetic retinopathy (DR) development is associated with disturbances in the gut microbiota and related metabolites. Butyric acid is one of the short-chain fatty acids (SCFAs), which has been found to possess a potential antidiabetic effect. However, whether butyrate has a role in DR remains elusive.

Highly Regioselective Dichalcogenation of Alkenyl Sulfonium Salts to Access 1,1-Dichalcogenalkenes.

An unprecedented geminal olefinic dichalcogenation of alkenyl sulfonium salts with dichalcogenides ArYYAr (Y = S, Se, Te) is reported, providing various trisubstituted 1,1-dichalcogenalkenes [ArCH = C(YAr)] in a highly selective manner under mild and catalyst-free conditions. The key process involves the formation of two geminal olefinic C-Y bonds via sequential C-Y cross-coupling and C-H chalcogenation. A mechanistic rationale is further supported by control experiments and density functional theory calculations.

Methods for Analyzing the Gut Microbiota in Diabetic Retinopathy.

The gut microbiome that inhabits human hosts plays an important role in the development of a healthy host immune system. Many studies have shown that gut microbiota is involved in the occurrence and development of diabetic retinopathy (DR). With the advent of sequencing technology of the bacterial 16S ribosomal RNA (rRNA) gene, microbiota studies are becoming more feasible.

Identification of alternative splicing events related to fatty liver formation in duck using full-length transcripts.

Background: Non-alcoholic fatty liver disease (NAFLD) is one of most common diseases in the world. Recently, alternative splicing (AS) has been reported to play a key role in NAFLD processes in mammals. Ducks can quickly form fatty liver similar to human NAFLD after overfeeding and restore to normal liver in a short time, suggesting that ducks are an excellent model to unravel molecular mechanisms of lipid metabolism for NAFLD.

Rhodium-Catalyzed Highly Enantio- and Diastereoselective Alkenylation of β,γ-Unsaturated Butenolides via Dynamic Kinetic Resolution.

A rhodium-catalyzed highly enantio- and diastereoselective alkenylation of β,γ-unsaturated butenolides is reported. The use of a chiral diene ligand, (,)-Ph-bod, enables the facile synthesis of chiral butyrolactones in high yields with extremely high enantioselectivities (>99% ee in all cases) and high diastereoselectivities (up to >20:1 dr). The key process of the reaction involves the isomerization of β,γ-unsaturated butenolides to racemic α,β-unsaturated butenolides and the subsequent dynamic kinetic resolution through ligand-controlled, enantioselective alkenylation with an alkenylrhodium species that is generated in situ via 1,4-rhodium migration.

Rhodium-Catalyzed Divergent Arylation of Alkenylsulfonium Salts with Arylboroxines.

A ligand-controlled rhodium-catalyzed regiodivergent arylation of alkenylthianthrenium salts with arylboroxines which allows the synthesis of terminal and internal alkene products in a switchable manner is reported. The use of a diene ligand guides the reaction toward cine-arylation affording terminal alkenes, while the use of a phosphine ligand switches the reaction to ipso-arylation exclusively giving internal alkenes. Deuterium labelling studies and DFT computations were carried out to investigate the mechanism.

Efficacy of machine learning assisted dental age assessment in local population.

Introduction: Although the dental age assessment is commonly applied in forensic and maturity evaluation, the long-standing dilemma from population differences has limited its application.

Objectives: This study aimed to verify the efficacy of the machine learning (ML) to build up the dental age standard of a local population.

Methods: We retrospectively studied 2052 panoramic films retrieved from healthy Taiwanese children aged 2.

Chiral Diene Ligands in Asymmetric Catalysis.

Asymmetric catalysis has emerged as a general and powerful approach for constructing chiral compounds in an enantioselective manner. Hence, developing novel chiral ligands and catalysts that can effectively induce asymmetry in reactions is crucial in modern chemical synthesis. Among such chiral ligands and catalysts, chiral dienes and their metal complexes have received increased attention, and a great progress has been made over the past two decades.

Rhodium/Chiral-Diene-Catalyzed Switchable Asymmetric Divergent Arylation of Enone-Diones.

A rhodium/chiral diene catalytic system is reported for the reaction of enone-diones and arylboronic acids that allows the switchable synthesis of chiral bicyclic products and acyclic products in a controlled manner. The production of bicyclic products containing four contiguous stereocenters is assumed to proceed through the enantioselective arylrhodation of enone-diones with CsCO, forming a rhodium-enolate intermediate, followed by desymmetrization of the diastereotopic diones via aldol cyclization with quantitative diastereoselection and excellent enantiomeric excess. The production of acyclic products is assumed to proceed through the enantioselective hydroarylation of enone-diones with excellent enantiomeric excess in which the aldol cyclization is significantly inhibited by the choice of EtN as a base.

Functional divergence of oligoadenylate synthetase 1 (OAS1) proteins in Tetrapods.

OASs play critical roles in immune response against virus infection by polymerizing ATP into 2-5As, which initiate the classical OAS/RNase L pathway and induce degradation of viral RNA. OAS members are functionally diverged in four known innate immune pathways (OAS/RNase L, OASL/IRF7, OASL/RIG-I, and OASL/cGAS), but how they functionally diverged is unclear. Here, we focus on evolutionary patterns and explore the link between evolutionary processes and functional divergence of Tetrapod OAS1.