Due to the easy preparation, high stability and environmental friendliness, nanozymes are frequently used as promising substitutes to natural enzymes. However, the efficacy of nanozymes in biomedicine aspects is often hampered by their potential biotoxicity and limited bioavailability, which prompted structure adaption or carrier design to maximize nanozymes performance. Despite considerable efforts on carriers to deliver nanozymes efficiently, the systematic studies on enzyme-like activities of nanozymes related to platforms of nanozyme@carrier are sparse.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
February 2025
Alkyl phosphonates are important motifs in medicinal chemistry, yet their efficient synthesis by direct C(sp)-H functionalization remains a challenge. Here, we report straightforward access to benzylic phosphonates by direct C(sp)-H functionalization in a cross-dehydrogenative-coupling reaction between non-specialized alkylarenes and unfunctionalized phosphites. Notably, the C-H substrates are used as the limiting reagents.
View Article and Find Full Text PDFDiabetes Metab Syndr Obes
August 2024
Background: Diabetic retinopathy (DR) is a prevalent ocular manifestation of diabetic microvascular complications and a primary driver of irreversible blindness. Existing studies have illuminated the presence of aberrant brain activity in individuals affected by DR. However, the alterations in the modular segregation of brain networks among DR patients remain inadequately understood.
View Article and Find Full Text PDFHerein, we disclose a simple copper-catalyzed method for enantioselective allylic C(sp)-H oxidation of unsymmetrical acyclic alkenes, specifically 1-aryl-2-alkyl alkenes. The C-H substrates are used in limiting amounts, and the products are obtained with high enantioselectivity, E/Z-selectivity, and regioselectivity. The method exhibits broad functional group tolerance, and E/Z-alkene mixtures are suitable C-H substrates.
View Article and Find Full Text PDFFoodborne illness caused by consuming foods contaminated by pathogens remains threating to the public health. Despite considerable efforts of using renewable source materials, it is highly demanding to fabricate food packaging with multiple properties including eco-friendliness, bactericidal effect and biocompatibility. Here, sodium lignosulfonate (SL) and ZnO nanoparticles (ZnO NPs) were used as functional filler and structure components, respectively, on the cellulose nanofibers (CNFs)-based films, which endows the produced membrane (CNF/SL-ZnO) the UV-light blocking, antioxidant, and antimicrobial characteristics.
View Article and Find Full Text PDFEnantioenriched chiral amines are of exceptional importance in the pharmaceutical industry. Recently, several new methods for the installation of these functional groups directly from non-acidic C(sp)-H bonds by catalytic intermolecular enantioselective amination have been reported. These methods represent significant advances of the field and most of them display high levels of enantioselectivity, utilize the C(sp)-H substrate as the limiting reagent, feature good functional group tolerance, and show compatibility with late-stage C(sp)-H amination of advanced substrates.
View Article and Find Full Text PDFAims: Although synthetic ZnO nanoparticles (Nano-ZnO) as an alternative of ZnO compounds have been extensively used such as in livestock production, the increased consuming of Nano-ZnO has raised considerable concerns in environmental pollution and public health. Because of the low digestion of Nano-ZnO, the systematic studies on their interactions with gut microbiota remain to be clarified.
Materials And Methods: Nano-ZnOs were prepared by co-precipitation (ZnO-cp) and high temperature thermal decomposition (ZnO-td) as well as the commercial type (ZnO-s).
Renal fibrosis is the pathological repair reaction of the kidney to chronic injury, which is an important process of chronic kidney disease (CKD) progressing to end-stage renal failure. Nephrolithiasis is one of the most common renal diseases, with waist and abdomen pain, hematuria, urinary tract infection, and other clinical symptoms, which can increase the risk of renal fibrosis. Oxalate crystal-induced kidney injury is an early stage of nephrolithiasis; it is of great significance to explore the mechanism for the prevention and treatment of nephrolithiasis.
View Article and Find Full Text PDF-Heterobiaryls are common skeletons found in biological molecules, pharmaceuticals and ligands. Herein, we document an efficient and redox-neutral photocatalytic system to obtain functionalized -heterobiaryls under mild conditions. Substrates bearing variegated functional groups are compatible with the developed photocatalytic conditions.
View Article and Find Full Text PDFOsteoporosis (OP) is a systemic bone disease characterized by decreased bone strength, microarchitectural changes in bone tissues, and increased risk of fracture. Its occurrence is closely related to various factors such as aging, genetic factors, living habits, and nutritional deficiencies as well as the disturbance of bone homeostasis. The dysregulation of bone metabolism is regarded as one of the key influencing factors causing OP.
View Article and Find Full Text PDFPediatric ulcerative colitis (UC) is a distinct type of inflammatory bowel disease with severe disease activity and rapid progression, which can lead to detrimental life-long consequences. The pathogenesis of pediatric UC remains unclear, although dysbiosis of the gut microbiota has been considered an important factor. In this study, we collected intestinal mucosal-luminal interface microbiota samples from a cohort of treatment-naïve pediatric UC or control patients and used two different mass spectrometry-based glycomic approaches to examine the N-glycans that were associated with the microbiota.
View Article and Find Full Text PDFEmerging evidence suggests bright prospects of some natural antioxidants in the treatment of osteoporosis. 6'-O-Galloylpaeoniflorin (GPF), an antioxidant isolated from peony roots (one of very widely used Oriental medicines, with various anti-inflammatory, antitumor, and antioxidant activities), shows a series of potential clinical applications. However, its effects on osteoporosis remain poorly investigated.
View Article and Find Full Text PDFAs an important component of the earth ecosystem, soil moisture monitoring is of great significance in the fields of crop growth monitoring, crop yield estimation, variable irrigation, and other related applications. In order to mitigate or eliminate the impacts of sparse vegetation covers in farmland areas, this study combines multi-source remote sensing data from Sentinel-1 radar and Sentinel-2 optical satellites to quantitatively retrieve soil moisture content. Firstly, a traditional Oh model was applied to estimate soil moisture content after removing vegetation influence by a water cloud model.
View Article and Find Full Text PDFA decarboxylative cross-coupling reaction of α-amino acids with nitrones via visible-light-induced photoredox catalysis has been established for easy access to β-amino hydroxylamines and vicinal diamines with structural diversity, which is featured with simple operation, mild conditions, readily available α-amino acids, and a broad scope of nitrone substrates. The application of this protocol can furnish efficient synthetic strategies for some valuable vicinal diamine-containing molecules.
View Article and Find Full Text PDFPresented here is a class of novel axially chiral aryl-p-quinones as platform molecules for the preparation of non-C symmetric biaryldiols. Two sets of aryl-p-quinone frameworks were synthesized with remarkable enantiocontrol by means of chiral phosphoric acid catalyzed enantioselective arylation of p-quinones by central-to-axial chirality conversion. These aryl-p-quinones were then used to access a wide spectrum of highly functionalized non-C symmetric biaryldiols with excellent retention of the enantiopurity.
View Article and Find Full Text PDFGlycosylation is one of the most important post-translational modifications in biological systems. Current glycoproteome methods mainly focus on qualitative identification of glycosylation sites or intact glycopeptides. However, the systematic quantitation of glycoproteins has remained largely unexplored.
View Article and Find Full Text PDFMonitoring serum glycomics is one of the most important emerging approaches for diagnosis of various cancers, and the majority of previous studies were based on MALDI-MS or HPLC analysis. Considering the difference of these analytical methods employed for serum glycomics, it is necessary to compare the effectiveness of different analytical methods for monitoring the aberrant changes in serum glycomics. In this study, a strategy based on machine learning was firstly applied for comparing the analysis results of MALDI-MS and HPLC on the same serum glycomics of hepatocellular carcinoma (HCC) samples.
View Article and Find Full Text PDFO-Acetylation of sialic acid in protein N-glycans is an important modification and can occur at either 4-, 7-, 8- or 9-position in various combinations. This modification is usually labile under alkaline reaction conditions. Consequently, a permethylation-based analytical method, which has been widely used in glycomics studies, is not suitable for profiling O-acetylation of sialic acids due to the harsh reaction conditions.
View Article and Find Full Text PDFMatrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has become an important technology for glycan analysis due to its ease of operation, short analysis time and impurity tolerance. However, the low ionization efficiency of N-glycans led to the difficulty in analyzing glycans of low abundance in complex biological samples due to the lack of basic site for protonation. Therefore, highly sensitive method for the glycans analysis is in urgent demand.
View Article and Find Full Text PDFSialic acids usually locate at the terminal of many glycan structures in either α(2,3) or α(2,6) linkage, playing different roles in various biological and pathological processes. Several linkage specific carboxyl derivatization methods have been reported to discriminate between α(2,3) and α(2,6)-linked sialic acids by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Among them, ethyl esterification was recently reported to achieve linkage specific derivatization between α(2,3) and α(2,6)-linked sialic acids with good selectivity.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
November 2015
An umpolung Mannich-type reaction of secondary amides, aliphatic aldehydes, and electrophilic alkenes has been disclosed. This reaction features the one-pot formation of C-N and C-C bonds by a titanocene-catalyzed radical coupling of the condensation products, from secondary amides and aldehydes, with electrophilic alkenes. N-substituted γ-amido-acid derivatives and γ-amido ketones can be efficiently prepared by the current method.
View Article and Find Full Text PDFMatrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been a major approach for glycan analysis. However, the preferential cleavage of the sialic acid moiety by in- and post-source decay influences the determination of sialylated glycans by MALDI-MS. Many chemical derivatization methods were introduced to stabilize the sialylated glycan during MALDI-MS.
View Article and Find Full Text PDFThe analysis of isomeric glycans is a challenging task. In this work, a new strategy was developed for isomer-specific glycan profiling using nanoLC-MS with PGC as the stationary phase. Native glycans were derivatized in the presence of methylamine and trispyrrolidinophosphonium hexafluorophosphate and reduced by the ammonia-borane complex.
View Article and Find Full Text PDFProfiling of glycans released from proteins is very complex and important. To enhance the detection sensitivity, chemical derivatization is required for the analysis of carbohydrates. Due to the interference of excess reagents, a simple and reliable purification method is usually necessary for the derivatized oligosaccharides.
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