Bioaccumulation mechanisms of perfluoroalkyl substances (PFASs) in aquatic environments: Theoretical and experimental insights.

Per- and polyfluoroalkyl substances (PFASs) are persistent, bioaccumulative contaminants found in water resources at levels hazardous to human health. However, the PFAS bioaccumulation mechanism remains poorly understood. In this study, we incorporated density functional theory (DFT), molecular dynamics (MD), and experiments to analyze the partitioning pathways and to establish the structure-bioaccumulation relationship.

Iodide Ion-Promoted Highly Regioselective Triazolization of Aldehydes via Desulfonation-Associated Direct Radical Coupling.

A highly efficient iodide ion (I)-promoted method for direct α-C(sp)-H triazolization of aldehydes has been developed for the regioselective synthesis of -substituted triazole derivatives. The developed method features the corresponding products in good yields (up to 99%) with an excellent functional group tolerance via an intermolecular oxidative radical coupling. Experimental mechanistic investigations indicate that the reaction proceeds via an I-promoted synergistic desulfonylation process, which provides a high regioselectivity.

Multifunctional chiral metal hydrogen-bonded organic frameworks constructed from lanthanide ions with a trigonal prismatic coordination environment.

Two pairs of chiral enantiomers D/L-Dy(PMP)·2HO (D-1/L-1) and D/L-Yb(PMP)·2HO (D-2/L-2) were synthesized by the introduction of enantiomerically pure D/L-PMP (PMP = (phosphonomethyl)proline) ligands into lanthanide coordination chemistry. The chiral characteristics of these products were confirmed by single crystal X-ray diffraction, second harmonic generation (SHG) measurements and circular dichroism (CD) spectroscopy. These complexes are composed of 1D chains constructed from lanthanide ions with a trigonal prismatic coordination geometry and PMP ligands.

Albumin-Chaperoned Deep-NIR Triarylmethane Dyes for High-Contrast In Vivo Imaging and Photothermal Therapy.

Fluorophores absorbing/emitting in the deep near-infrared (deep NIR) spectral region, that is, 800 nm and beyond, hold great promise for in vivo bioimaging, diagnosis, and phototherapy due to deeper tissue penetration. The bottleneck is the lack of bright, stable, and readily synthesized deep NIR fluorophores. Here, it is reported that the albumin-chaperon strategy is a viable one-for-all strategy to address these difficulties.

The involvement and possible targeting of cardiolipins degradation and disturbed linoleic acid metabolism in cardiac atrophy under cancer cachexia.

Cardiac atrophy is one of the critical characteristics of cancer cachexia though its mechanisms had not been fully clarified. In the present study, to study the mechanisms of cardiac atrophy in cancer cachexia and search for possible drug targets, cancer cachexia mice bearing C26 colon tumor cells and cultured H9c2 cardiomyocytes induced with simulated cancer cachexia injuries were used as in vivo and in vitro model, respectively. Results of both spatial metabolomics and LC-MS non-targeted metabolomics analysis of heart tissues suggested the disturbance of glycerophospholipid and fatty acid metabolism in the cancer cachexia hearts.

Catalyst-free and wavelength-tuned glycosylation based on excited-state intramolecular proton transfer.

The chemoselectivity of organic reactions is a fundamental topic in organic chemistry. In the long history of chemical synthesis, achieving chemoselectivity is mainly limited to thermodynamic conditions by an exogenous activation strategy. Here, we design an endogenous activation method, which can be used to control the chemoselectivity of phenol and naphthol through the photo-induced excited-state intramolecular proton transfer (ESIPT).

A temperature-ultrasound sensitive nanoparticle delivery system for exploring central neuroinflammation mechanism in stroke-heart syndrome.

Background: Cardiovascular events secondary to stroke-collectively classified as stroke-heart syndrome-greatly impair the patient's prognosis, however its underlying mechanism has yet to be determined. To investigate the mechanism of central neuroinflammation and its effects on stroke-heart syndrome, a temperature-ultrasound responsive brain-targeted drug delivery system, DATS/MION-LPE, was synthesized to specifically study neuroinflammation in the mouse middle cerebral artery occlusion (MCAO) model.

Results: The specific polymer of DATS/MION-LPE can close the nanoparticle pores at 37 °C, restricting drug release in the circulation.

Selective hydrogenolysis of the Csp-O bond in the furan ring using hydride-proton pairs derived from hydrogen spillover.

Selective hydrogenolysis of biomass-derived furanic compounds is a promising approach for synthesizing aliphatic polyols by opening the furan ring. However, there remains a significant need for highly efficient catalysts that selectively target the Csp-O bond in the furan ring, as well as for a deeper understanding of the fundamental atomistic mechanisms behind these reactions. In this study, we present the use of Pt-Fe bimetallic catalysts supported on layered double hydroxides [PtFe /LDH] for the hydrogenolysis of furanic compounds into aliphatic alcohols, achieving over 90% selectivity toward diols and triols.

Membrane-free Electrolysis Production of Hydrogen Peroxide on Low-cost Metal-free Electrocatalysts for Dye Degradation.

The efficient production of hydrogen peroxide (HO) solution was achieved by combining cathodic two-electron oxygen reduction (2e ORR) and anodic two-electron water oxidation (2e WOR) in two half-reaction cells. h-BN loaded on carbon fibers (h-BN@C) is prepared and employed as an anode material to catalyze 2e WOR, while sulfonated commercial BP-2000 carbons (BP-2000-SOH) were prepared as the cathode materials for 2e ORR. In a 2 M KHCO solution, an overall Faradaic efficiency of 97 % and a total HO production rate of 1872 mmol g h over metal-free electrodes were accomplished in a membrane-free flow cell.

Room-temperature selective cyclodehydrogenation on Au(111) via radical addition of open-shell resonance structures.

Cyclodehydrogenation is an important ring-formation reaction that can directly produce planar-conjugated carbon-based nanomaterials from nonplanar molecules. However, inherently high C-H bond energy necessitates a high temperature during dehydrogenation, and the ubiquity of C - H bonds in molecules and small differences in their bond energies hinder the selectivity of dehydrogenation. Here, we report a room-temperature cyclodehydrogenation reaction on Au(111) via radical addition of open-shell resonance structures and demonstrate that radical addition significantly decreases cyclodehydrogenation temperature and further improves the chemoselectivity of dehydrogenation.

Smiles-Rearrangement-Based One-Pot Synthesis of Diarylacetylenes from Benzylic Sulfones and Methyl Benzoates Mediated by LiN(SiMe)/KN(SiMe).

The one-pot synthesis of diphenylacetylene by the reaction of methyl benzoate with 1-(benzylsulfonyl)-3,5-di(trifluoromethyl)benzene was developed. The combination of LiN(SiMe) and KN(SiMe) is key to promoting the reaction. Simply combining methyl benzoate, 1-(benzylsulfonyl)-3,5-di(trifluoromethyl)benzene, LiN(SiMe), and KN(SiMe) can produce a variety of diaryl acetylenes (28 examples, 18-70% yields).

ChemXTree: A Feature-Enhanced Graph Neural Network-Neural Decision Tree Framework for ADMET Prediction.

The rapid progression of machine learning, especially deep learning (DL), has catalyzed a new era in drug discovery, introducing innovative approaches for predicting molecular properties. Despite the many methods available for feature representation, efficiently utilizing rich, high-dimensional information remains a significant challenge. Our work introduces ChemXTree, a novel graph-based model that integrates a Gate Modulation Feature Unit (GMFU) and neural decision tree (NDT) in the output layer to address this challenge.

Tetrahedral DNA Framework-Based Spherical Nucleic Acids for Efficient siRNA Delivery.

Spherical nucleic acids (SNAs) hold substantial therapeutic potential for the delivery of small interfering RNAs (siRNAs). Nevertheless, their potential remains largely untapped due to the challenges of cytosolic delivery. Inspired by the dynamic, spiky architecture of coronavirus, an interface engineering approach based on a tetrahedral DNA framework (tDF) is demonstrated for the development of coronavirus-mimicking SNAs.

Synthesis of Functionalized Cycloheptadienones Starting from Phenols and Using a Rhodium/Boron Asymmetric Catalytic System.

Skeletal editing offers a unique route to assemble complex architectures from simple feedstocks that are otherwise difficult to obtain. However, the asymmetric version of skeletal editing has not been widely studied. Herein, we present a modular rhodium/boron asymmetric catalytic system that enables ring-expansion of phenols with cyclopropenes to synthesize highly functionalized cycloheptadienones in excellent chemo- and regioselectivities.

α-Nucleophilic Addition to α,β-Unsaturated Carbonyl Compounds via Photocatalytically Generated α-Carbonyl Carbocations.

We report the photocatalytic oxidation of α-carbonyl radicals of amides or esters to the corresponding α-carbonyl carbocations through super photoreductant CBZ6 induced redox-neutral photocatalysis. The α-carbonyl radicals are formed by the β-addition of alkyl radicals generated in situ by the photocatalytic fragmentation of N-hydroxyphthalimide esters to the α,β-unsaturated amides and esters. This method enables the α-nucleophilic addition of hydroxyl or alkoxyl radicals to amides and esters without any prefunctionalization.

Non-natural sialic acid derivatives with -nitrobenzyl alcohol substituents for light-mediated protein conjugation and cell imaging.

We have synthesized two sialic acid derivatives substituted with an -nitrobenzyl alcohol (o-NBA) group that can undergo light-mediated conjugation with primary amines at their 5- or 9-carbon position. The o-NBA derivatives were shown to react with multiple lysine residues of human serum albumin (HSA) when exposed to 365 nm light irradiation within 10 min. The resulting sugar conjugates were characterized by mass spectroscopy and used for fluorescence-based cell imaging.

Self-validating photoelectrochemical/photoelectrochromic visual sensing platform for ciprofloxacin precise detection in milk.

Background: In the process of food production, ciprofloxacin (CIP), a highly prescribed fluoroquinolone antibiotic, is often excessively used to reduce the risk of bacterial infection. However, this overuse can cause severe harm to human health, including allergic responses, gastrointestinal complications, and potential renal dysfunction. The development of a robust and precise detection method for CIP is crucial, given the interconnection between food security and human health.

A Self-Immobilizing Photosensitizer with Long-Term Retention for Hypoxia Imaging and Enhanced Photodynamic Therapy.

The precise theranostic strategy of fluorescence imaging-guided photodynamic therapy (PDT) can effectively mitigate the adverse effect of photosensitizers in normal cells and tissues. However, low tumor enrichment and high diffusivity of photosensitizers significantly compromise the imaging accuracy and PDT effect. In this study, we have developed a nitroreductase (NTR)-activated and self-immobilizing photosensitizer CyNT-F, which showed enhanced enrichment in tumor tissues and facilitated precise and sustained imaging as well as PDT for hypoxia tumors.

Flavin-containing monooxygenase 2 confers cardioprotection in ischemia models through its disulfide bond catalytic activity.

Myocardial infarction (MI) is characterized by massive cardiomyocyte (CM) death and cardiac dysfunction, and effective therapies to achieve cardioprotection are greatly needed. Here, we report that flavin-containing monooxygenase 2 (FMO2) levels were markedly increased in CMs in both ex vivo and in vivo models of ischemic injury. Genetic deletion of FMO2 resulted in reduced CM survival and enhanced cardiac dysfunction, whereas CM-specific FMO2 overexpression conferred a protective effect in infarcted rat hearts.

Nanozyme-chitosan-aerogel immobilized enzyme-driven biocatalytic cascade for therapeutic engineering of diabetic wounds.

A novel strategy that has emerged in recent years involves the use of aerogels for anti-inflammatory treatment, which has been extensively studied for its powerful application prospects in wound healing, diabetic complications, and tissue regeneration. However, the therapeutic efficacy of aerogels alone is compromised due to bacterial infections at the wound site. Therefore, it is necessary to incorporate effective antibacterial systems onto the aerogels to enhance their efficacy against bacterial infections.

Base-promoted tandem ring-opening/ring-closing of -alkynyl-2-oxazolidinones enables facile synthesis of 2-oxazolines.

A KCO-promoted tandem ring-opening/ring-closing of -alkynyl-2-oxazolidinones has been described, affording 2-oxazolines in 42-99% yields without column chromatography isolation. This operationally simple reaction proceeds under ambient conditions without a transition-metal catalyst and an external oxidant and can be applied for the late-stage functionalization of biologically active compounds.

Triphyrin(2.1.1) with Tunable Skeletons and Properties Based on the Confusion Approach.

The N-confused [14]triphyrin(2.1.1) was facilely synthesized and readily converted into N-confused triphyrinone(2.