Switchable Chemo-, Regio- and Pseudo-Stereodivergence in Palladium-Catalyzed Cycloaddition of Allenes.

Here, we report a strategy enabling triple switchable chemo-, regio-, and stereodivergence in newly developed palladium-catalyzed cycloadditions of allenes. An asymmetric pseudo-stereodivergent cycloaddition of allenes bearing a primary leaving group at the α-position, where a dynamic kinetic asymmetric hydroalkoxylation of racemic unactivated allenes was the enantio-determining step, is realized, providing four stereoisomers [(Z,R), (Z,S), (E,S), and (E,R)] containing a di-substituted alkene scaffold and a stereogenic center. By tuning reaction conditions, a mechanistically distinctive cycloaddition is uncovered selectively with the same set of substrates.

A high heterozygosity genome assembly of Aedes albopictus enables the discovery of the association of PGANT3 with blood-feeding behavior.

The Asian tiger mosquito, Aedes albopictus, is a global invasive species, notorious for its role in transmitting dangerous human arboviruses such as dengue and Chikungunya. Although hematophagous behavior is repulsive, it is an effective strategy for mosquitoes like Aedes albopictus to transmit viruses, posing a significant risk to human health. However, the fragmented nature of the Ae.

Tumor-infiltrating macrophage associated lncRNA signature in cutaneous melanoma: implications for diagnosis, prognosis, and immunotherapy.

Along with the increasing knowledge of long noncoding RNA, the interaction between the long noncoding RNA (lncRNA) and tumor immune infiltration is increasingly valued. However, there is a lack of understanding of correlation between regulation of specific lncRNAs and tumor-infiltrating macrophages within melanoma. In this research, a macrophage associated lncRNA signature was identified by multiple machine learning algorithms and the robust and effectiveness of signature also validated in other independent datasets.

Phenolic acid-induced phase separation and translation inhibition mediate plant interspecific competition.

Phenolic acids (PAs) secreted by donor plants suppress the growth of their susceptible plant neighbours. However, how structurally diverse ensembles of PAs are perceived by plants to mediate interspecific competition remains a mystery. Here we show that a plant stress granule (SG) marker, RNA-BINDING PROTEIN 47B (RBP47B), is a sensor of PAs in Arabidopsis.

Analysis of risk factors associated with healthcare-associated carbapenem-resistant Klebsiella pneumoniae infection in a large general hospital: a case-case-control study.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection is a major public health threat in the world. To inform the prevention and control of CRKP infection in hospitals, this study analyzed the factors associated with CRKP infection and resistance to carbapenems in K. pneumoniae.

Analysis of healthcare-associated infection in patients with pulmonary arterial hypertension associated with congenital heart disease in PICU: Evidence from a tertiary hospital in western China.

Objective: The present study intends to analyze the targeted surveillance and risk factors for healthcare-associated infection (HAI) in patients with pulmonary arterial hypertension associated with congenital heart disease (CHD-PAH) in a Pediatric intensive care unit (PICU), and provide basis for formulating relevant prevention and control measures of HAI.

Methods: Children (≤14 years old) who were admitted to the PICU for ≥2 calendar days from January 2018 to December 2021 were included. Targeted surveillance of HAI was described.

Catalytic Enantioselective Desymmetrization of Prochiral Triacylamines via Pseudopeptidic Guanidine-Guanidinium Catalysis.

Triacylamines with symmetry have been explored in asymmetric organocatalysis, leading to the development of a novel catalytic enantioselective desymmetrization of prochiral triacylamines by methanolysis under the catalysis of chiral pseudopeptidic guanidine-guanidinium salt having a weakly coordinating anion. This organocatalytic methodology provides an effective approach to the synthetically useful chiral imide-esters with a 1,5-dicarbonyl moiety, and its synthetic potential has been manifested in the asymmetric synthesis of two GABA analogue drugs, ()-Baclofen·HCl and ()-Pregabalin.

Analysis on vaccine hesitation and its associated factors among parents of preschool children in Songgang Street, Shenzhen.

China has the largest number of vaccinated population around the world. However, there has been few research on the prevalence and associated factors of vaccine hesitation among parents of preschool children. Therefore, we conducted this study to evaluate the status of vaccine hesitation and its associated factors among children's parents.

Direct access to spirocycles by Pd/WingPhos-catalyzed enantioselective cycloaddition of 1,3-enynes.

Spirocycles play an important role in drug discovery and development. The direct, catalytic, and enantioselective synthesis of spirocycles from readily available starting materials and in an atom economic manner remains a highly sought-after task in organic synthesis. Herein, an enantioselective Pd-hydride-catalyzed cycloaddition method for the synthesis of spirocyclic compounds directly from two classes of commonly available starting materials, 1,3-enynes and cyclic carbon-hydrogen (C-H) bonds, is reported.

Tandem (2 + 2) Annulation/Retro-4π Electrocyclization/Imino-Nazarov Cyclization Reaction of -Quinone Methides with Ynamides: Expeditious Construction of Functionalized Aminoindenes.

A new tandem annulation of -quinone methides (-QMs) with ynamides is described. This cascade reaction features a unique combination of (2 + 2) annulation, retro-4π electrocyclization, and imino-Nazarov cyclization, wherein vinyl -quinone methides (-VQMs) as one of the key intermediates have been identified chemically. Significantly, an unusual structural reconstruction of -QMs involving the cleavage of the C5-C6 bond and the late-stage formation of the C4-C6 bond is involved, leading to a methodology development for the construction of functionalized aminoindenes.

Comparative analysis of mite genomes reveals positive selection for diet adaptation.

Diet is a powerful evolutionary force for species adaptation and diversification. Acari is one of the most abundant clades of Arachnida, exhibiting diverse dietary types, while the underlying genetic adaptive mechanisms are not fully understood. Based on comparative analyses of 15 Acari genomes, we found genetic bases for three specialized diets.

Study Protocol: Design and Implementation of the Pediatric Liver Transplantation Biobank.

Early treatment of neonatal biliary atresia (BA) and other end-stage liver diseases can delay or prevent the necessity of liver transplantation (LT). The establishment of a standardized clinical pediatric liver transplantation (PLT) biobank is the prerequisite for scientific research, which helps to provide a qualified sample resource platform for research. Following standardized procedures to establish biobanks, the operational processes and quality control system were formulated.

Identification of an intraocular microbiota.

The current dogma in ophthalmology and vision research presumes the intraocular environment to be sterile. However, recent evidence of intestinal bacterial translocation into the bloodstream and many other internal organs including the eyes, found in healthy and diseased animal models, suggests that the intraocular cavity may also be inhabited by a microbial community. Here, we tested intraocular samples from over 1000 human eyes.

Clinical outcomes and risk factors for mortality from ventilator-associated events: A registry-based cohort study among 30,830 intensive care unit patients.

Objective: To investigate the clinical impact of ventilator-associated events (VAEs) on adverse prognoses and risk factors for mortality among intensive care unit (ICU) patients receiving invasive mechanical ventilation (IMV) based on an ICU healthcare-associated infection (ICU-HAI) registry.

Design: A cohort study was conducted based on an ICU-HAI registry including 30,830 patients between 2015 and 2018.

Setting: The study was conducted using data from 5 adult ICUs of a referral hospital.

Palladium-Catalyzed Asymmetric Direct Intermolecular Allylation of α-Aryl Cyclic Vinylogous Esters: Divergent Synthesis of (+)-Oxomaritidine and (-)-Mesembrine.

We demonstrate that α-aryl cyclic vinylogous esters are competent substrates in the direct intermolecular Pd-catalyzed asymmetric allylic alkylation, enabling a straightforward enantioselective synthesis of 6-allyl-6-aryl-3-ethoxycyclohex-2-en-1-ones, common motifs embedded in numerous structurally diverse natural products. As an initial demonstration of the utility of this protocol, the first catalytic enantioselective total synthesis of (+)-oxomaritidine and an improved five-step catalytic enantioselective synthesis of (-)-mesembrine have been completed divergently.

Palladium-Catalyzed Asymmetric (4 + 2) Annulation of γ-Methylidene-δ-valerolactones with Alkenes: Enantioselective Synthesis of Functionalized Chiral Cyclohexyl Spirooxindoles.

An unprecedented asymmetric catalytic (4 + 2) annulation reaction of aryl-substituted γ-methylidene-δ-valerolactones (GMDVs) with isatin-derived -quinone methides (-QMs) has been developed under the catalysis of palladium(0) and (,,)-(-)-Xyl-SKP, offering a new approach for the diastereo- and enantioselective synthesis of chiral cyclohexadienone-fused cyclohexyl spirooxindoles. Significantly, three highly congested contiguous tetrasubstituted carbon atoms embedded in bispirocyclic skeleton, of which two are vicinal quaternary stereogenic centers, are forged in an effective and selective manner (up to 99% yield, up to 95% ee, >20/1 dr). The current reaction represents the first exploration of enantioselective catalytic (4 + 2) annulation forming the six-membered carbocycles in the chemistry of both GMDVs and -QMs.

P(NMe)-Mediated Umpolung Spirocyclopropanation Reaction of -Quinone Methides: Diastereoselective Synthesis of Spirocyclopropane-Cyclohexadienones.

An unprecedented umpolung spirocyclopropanation reaction of -quinone methides and α-keto carbonyls is described. Our umpolung strategy based on 1,6-conjugate addition and intramolecular nucleophilic substitution offers a new method for effective access to a series of highly functionalized spirocyclohexadienonyl cyclopropanes having two vicinal quaternary carbons in ≤98% yield and >20:1 dr. Significantly, cyclic and acyclic topological structures of α-keto carbonyls as 1,1-dipole one-carbon synthons have a distinct influence on the stereochemistry of products, showing a reversal of diastereoselectivity in this P(NMe)-mediated umpolung spirocyclopropanation.

Palladium-Catalyzed Asymmetric (2+3) Annulation of -Quinone Methides with Trimethylenemethanes: Enantioselective Synthesis of Functionalized Chiral Spirocyclopentyl -Dienones.

A novel asymmetric catalytic (2+3) annulation of -quinone methides with CN-substituted trimethylenemethane is described under palladium catalysis, providing an alternative approach for the enantioselective construction of highly functionalized chiral spirocyclopentyl -dienones. Driven by the significant improvement in the reactivity and enantioselectivity, a novel type of non--symmetric phosphoramidite ligand from the chirality-matched combination of ()-BINOL and sterically demanding amine derived from l-hydroxyproline is evolved and explored for the protocol presented here.

Unplanned surgical reoperations as a quality indicator in pediatric tertiary general surgical specialties: Associated risk factors and hospitalization, a retrospective case-control analysis.

Unplanned reoperations have not been studied extensively in pediatric patients, especially concerning risk factors. We aim to estimate the rate of unplanned reoperations and to determine the associated factors in pediatric general surgical specialties.This analysis included a retrospective case-control study of unplanned reoperations from July 1, 2010 to June 30, 2017 in the general surgical specialties.

Enantioselective synthesis of chiral α-alkynylated thiazolidones by tandem S-addition/acetalization of alkynyl imines.

A SPINOL-derived chiral phosphoric acid catalyzed asymmetric formal [2 + 3]-annulation of in situ generated alkynyl imines and 1,4-dithiane-2,5-diol has been developed to afford enantiopure α-alkynylated thiazolidones with up to 72% yield and 98.5 : 1.5 er.

Catalytic Asymmetric [4 + 2] Cycloaddition of -Alkenyl Naphthols/Phenols with -Quinone Methides: Highly Stereoselective Synthesis of Chiral 2,3,4-Trisubstituted Chromans.

Chiral phosphoric acid-catalyzed biomimetic asymmetric [4 + 2] cycloaddition of -alkenyl naphthols/phenols and -quinone methides (-QMs) has been demonstrated to afford various important 2,3,4-trisubstituted chromans in high yields with excellent enantio- and diastereoselectivities (up to 99% yield, 99% ee, >20:1 dr). Notably, this methodology not only enabled access to the chiral trisubstituted chromans from 1-alkenyl 2-naphthols but also is compatible with 2-alkenyl 1-naphthols and phenols to deliver chiral trisubstituted chromans.

Geographic Difference Shaped Human Ocular Surface Metagenome of Young Han Chinese From Beijing, Wenzhou, and Guangzhou Cities.

Purpose: Microbial ecosystems interact with the human body and affect human health. The microbial community on the ocular surface remains an underexplored territory despite its importance as the first line of defense barrier that protects the eye and ultimately sight. We investigated how age and sex affected human ocular surface microbiome, and in the present study wanted to understand how geographic difference shaped the microbiome in the ocular surface.

Metagenomic analysis reveals gestational diabetes mellitus-related microbial regulators of glucose tolerance.

Aims: Recent studies have suggested a possible association between microbiota and gestational diabetes (GDM). However, the results are inconsistent. Our objective was to investigate further the relationship between GDM and microbiota and verify the potential microbial marker.