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1.
J Extracell Vesicles ; 13(9): e12505, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39235072

ABSTRACT

Reactive oxygen species (ROS)-induced oxidative DNA damages have been considered the main cause of mutations in genes, which are highly related to carcinogenesis and tumour progression. Extracellular vesicles play an important role in cancer metastasis. However, the precise role of DNA oxidative damage in extracellular vesicles (EVs)-mediated cancer cell migration and invasion remains unclear. Here, we reveal that ROS-mediated DNA oxidative damage signalling promotes tumour metastasis through increasing EVs release. Mechanistically, 8-oxoguanine DNA glycosylase (OGG1) recognises and binds to its substrate 8-oxo-7,8-dihydroguanine (8-oxoG), recruiting NF-κB to the synaptotagmin 7 (SYT7) promoter and thereby triggering SYT7 transcription. The upregulation of SYT7 expression leads to increased release of E-cadherin-loaded EVs, which depletes intracellular E-cadherin, thereby inducing epithelial-mesenchymal transition (EMT). Notably, Th5487, the inhibitor of DNA binding activity of OGG1, blocks the recognition and transmission of oxidative signals, alleviates SYT7 expression and suppresses EVs release, thereby preventing tumour progression in vitro and in vivo. Collectively, our study illuminates the significance of 8-oxoG/OGG1/SYT7 axis-driven EVs release in oxidative stress-induced tumour metastasis. These findings provide a deeper understanding of the molecular basis of cancer progression and offer potential avenues for therapeutic intervention.


Subject(s)
DNA Glycosylases , Extracellular Vesicles , Neoplasm Metastasis , Animals , Female , Humans , Mice , Cell Line, Tumor , Cell Movement , DNA Damage , DNA Glycosylases/metabolism , Epithelial-Mesenchymal Transition , Extracellular Vesicles/metabolism , Guanine/analogs & derivatives , Guanine/metabolism , NF-kappa B/metabolism , Oxidative Stress , Reactive Oxygen Species/metabolism , Signal Transduction
2.
J Hazard Mater ; 480: 135862, 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39293169

ABSTRACT

The development of multifunctional nanofibrous membranes (NFMs) that enable anti-viral protection during air purification and respiratory disease diagnosis for health management is of increasing importance. Herein, we unraveled a heterostructure-enhanced electro-induced stereocomplexation (HEIS) strategy to fabrication of poly(lactic acid) (PLA) NFMs enabling a combination of efficient PM removal, respiratory monitoring and self-sterilization. The strategy involved an electro-induced stereocomplexation (EIS) approach to trigger the generation of hydrogen bonds between enantiomeric poly(L-lactic acid) (PLLA) and poly(D-lactic acid) (PDLA) chains, promoting CO dipole alignment and molecular polarization during electrospinning. This was further enhanced by incorporation of Ag-doped TiO2 (Ag-TIO) nanodielectrics to promote the electroactivity and surface activity, conferring profound refinement of PLA nanofibers (from 460 nm to an ultralow level of 168 nm) and high porosities of over 91 %. Arising from the sustainable generation of plentiful charges based on triboelectric nanogenerator (TENG) mechanisms, the electroactive PLA NFMs exhibited remarkable triboelectric properties even in high-humidity environments (80 %RH), excellent PM0.3 filtration efficiency with an ultralow pressure drop (93.1 %, 31.8 Pa, 32 L/min), and 100 % antimicrobial efficiency against both E. coli and S. aureus. Moreover, a deep-learning algorithm based on convolutional neural network (CNN) was proposed to recognize various respiratory patterns. The proposed strategy confers the biodegradable NFMs an unusual combination of ultralow-resistance air purification and machine learning-assisted health management, signifying promising prospects in environmental protection and personal healthcare.

3.
Biochemistry ; 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39320967

ABSTRACT

Synaptotagmin 7 (SYT7), a member of the synaptotagmin family, exhibits high expression in various tumors and is closely associated with patient prognosis. The tight regulation of SYT7 expression assumes paramount significance in the progression of tumorigenesis. In this study, we detected a high GC content in the first 1000 bp of the promoter region of SYT7, suggesting a potential role of the G-quadruplex in its transcriptional regulation. Circular dichroism spectroscopy results showed that -187 to -172 bp sequence can form a typical parallel G-quadruplex structure, and site mutation revealed the critical role of the ninth guanine in its formation. Then, treatment of two ligands of G-quadruplex (TMPyP4 and Pyridostatin) reduced both the expression of SYT7 and subsequent tumor proliferation, demonstrating the potential of the G-quadruplex as a targeted therapy for tumors. By shedding light on the pivotal role of the G-quadruplex in regulating SYT7 transcription, our study not only advances our comprehension of this intricate regulatory mechanism but also emphasizes the significance of SYT7 in tumor proliferation. These findings collectively contribute to a more comprehensive understanding of the interplay between G-quadruplex regulation and SYT7 function in tumor development.

4.
Nat Commun ; 15(1): 6909, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39134527

ABSTRACT

Late-stage specific and selective diversifications of peptides and proteins performed at target residues under ambient conditions are recognized to be the most facile route to various and abundant conjugates. Herein, we report an orthogonal modification of cysteine residues using alkyl thianthreium salts, which proceeds with excellent chemoselectivity and compatibility under mild conditions, introducing a diverse array of functional structures. Crucially, multifaceted bioconjugation is achieved through clickable handles to incorporate structurally diverse functional molecules. This "two steps, one pot" bioconjugation method is successfully applied to label bovine serum albumin. Therefore, our technique is a versatile and powerful tool for late-stage orthogonal bioconjugation.


Subject(s)
Cysteine , Peptides , Serum Albumin, Bovine , Cysteine/chemistry , Peptides/chemistry , Serum Albumin, Bovine/chemistry , Salts/chemistry , Click Chemistry/methods , Animals , Proteins/chemistry , Cattle
5.
Infect Genet Evol ; 123: 105654, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39111344

ABSTRACT

Melioidosis is a zoonotic disease, with its outbreaks being rare and indicative of an unusual concurrence of extreme climate and natural environmental factors. An outbreak of melioidosis cases emerged in Hainan following Typhoon "Dianmu" from October to December 2021, presenting an opportunity to identify the environmental sources of infection for these cases due to its nature as a well-defined point-source cluster. To investigate the relationship between the occurrence of these melioidosis cases and the environment, we extracted the entire genome of 25 clinical strains and conducted MLST typing, followed by whole genome sequencing and analysis of molecular genetic information for four ST46 genotypes from these strains. Phylogenetic and evolutionary relationships between Hainan sequence types (STs) and those found in other endemic regions were analyzed using IslandPath-DIMO, PHASTER, e-BURST, PHYLOViZ, and the maximum likelihood method. Notably, a total of 25 clinical strains were identified, encompassing 12 STs (ST46, ST1105, ST1991, ST30, ST1992, ST50, ST164, ST55, ST70, ST1993, ST1545, and ST58), with ST1991, ST1992, and ST1993 being newly discovered subtypes. PHYLOViZ clustering analysis divided the strains into two groups (A and B), both closely related to the Asian region. Phylogenetic tree analysis further revealed that most of the strains in this study were closely related to those found in Australia and Thailand. Analysis of patient information and visits to their residences suggested that contaminated water sources might be the primary source of infection during this outbreak. Our findings underscore that extreme weather events, such as typhoons, significantly increase the infection rate of B. pseudomallei, along with its genetic diversity, necessitating additional prevention strategies to control these B. pseudomallei infections.


Subject(s)
Burkholderia pseudomallei , Disease Outbreaks , Genetic Variation , Melioidosis , Multilocus Sequence Typing , Phylogeny , Melioidosis/epidemiology , Melioidosis/microbiology , Humans , Burkholderia pseudomallei/genetics , Burkholderia pseudomallei/classification , Evolution, Molecular , China/epidemiology , Whole Genome Sequencing , Genotype
6.
ACS Appl Mater Interfaces ; 16(34): 45078-45090, 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39155485

ABSTRACT

The advancement of intelligent and biodegradable respiratory protection equipment is pivotal in the realm of human health engineering. Despite significant progress, achieving a balance between efficient filtration and intelligent monitoring remains a great challenge, especially under conditions of high relative humidity (RH) and high airflow rate (AR). Herein, we proposed an interfacial stereocomplexation (ISC) strategy to facilitate intensive interfacial polarization for poly(lactic acid) (PLA) nanofibrous membranes, which were customized for machine learning-assisted respiratory diagnosis. Theoretical principles underlying the facilitated formation of the electroactive phase and aligned PLA chains were quantitatively depicted in the ISC-PLA nanofibers, contributing to the increased dielectric constant and surface potential (as high as 2.2 and 5.1 kV, respectively). Benefiting from the respiration-driven triboelectric mechanisms, the ISC-PLA demonstrated a high PM0.3 filtration efficiency of over 99% with an ultralow pressure drop (75 Pa), even in challenging circumstances (95 ± 5% RH, AR of 85 L/min). Furthermore, we implemented the ISC-PLA with multifunction respiratory monitoring (response time of 0.56 s and recovery time of 0.25 s) and wireless transmission technology, yielding a high recognition rate of 83% for personal breath states. This innovation has practical implications for health management and theoretical advancements in respiratory protection equipment.


Subject(s)
Humidity , Machine Learning , Nanofibers , Polyesters , Polyesters/chemistry , Nanofibers/chemistry , Humans , Monitoring, Physiologic/instrumentation , Monitoring, Physiologic/methods
7.
Hum Vaccin Immunother ; 20(1): 2385654, 2024 Dec 31.
Article in English | MEDLINE | ID: mdl-39193797

ABSTRACT

Cancer remains a major global health challenge. Immunotherapy has revolutionized the management of cancer, yet only a limited number of patients respond to such treatments. This is largely attributed to the immunosuppressive tumor microenvironment, which diminishes the effectiveness of immunotherapy. Recent studies have underscored the potential of naturally derived caerin 1 peptides, particularly caerin 1.1 and caerin 1.9, which exhibit strong antitumor effects and enhance the efficacy of immunotherapies in animal models. This review encapsulates the current research aimed at augmenting the effectiveness of immunotherapy, focusing on the role of caerin 1.1 and caerin 1.9 in boosting immunotherapeutic outcomes, elucidating possible mechanisms, and discussing their limitations and challenges.


Subject(s)
Immunotherapy , Neoplasms , Tumor Microenvironment , Humans , Neoplasms/therapy , Neoplasms/immunology , Immunotherapy/methods , Animals , Tumor Microenvironment/immunology , Antimicrobial Cationic Peptides/immunology , Antimicrobial Cationic Peptides/therapeutic use , Peptides/immunology , Peptides/therapeutic use
8.
J Cell Mol Med ; 28(14): e18375, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39039796

ABSTRACT

Celastrol, a bioactive molecule extracted from the plant Tripterygium wilfordii Hook F., possesses anti-inflammatory, anti-obesity and anti-tumour properties. Despite its efficacy in improving erythema and scaling in psoriatic mice, the specific therapeutic mechanism of celastrol in atopic dermatitis (AD) remains unknown. This study aims to examine the role and mechanism of celastrol in AD using TNF-α-stimulated HaCaT cells and DNCB-induced Balb/c mice as in vitro and in vivo AD models, respectively. Celastrol was found to inhibit the increased epidermal thickness, reduce spleen and lymph node weights, attenuate inflammatory cell infiltration and mast cell degranulation and decrease thymic stromal lymphopoietin (TSLP) as well as various inflammatory factors (IL-4, IL-13, TNF-α, IL-5, IL-31, IL-33, IgE, TSLP, IL-17, IL-23, IL-1ß, CCL11 and CCL17) in AD mice. Additionally, celastrol inhibited Ezrin phosphorylation at Thr567, restored mitochondrial network structure, promoted translocation of Drp1 to the cytoplasm and reduced TNF-α-induced cellular reactive oxygen species (ROS), mitochondrial ROS (mtROS) and mitochondrial membrane potential (MMP) production. Interestingly, Mdivi-1 (a mitochondrial fission inhibitor) and Ezrin-specific siRNAs lowered inflammatory factor levels and restored mitochondrial reticular formation, as well as ROS, mtROS and MMP production. Co-immunoprecipitation revealed that Ezrin interacted with Drp1. Knocking down Ezrin reduced mitochondrial fission protein Drp1 phosphorylation and Fis1 expression while increasing the expression of fusion proteins Mfn1 and Mfn2. The regulation of mitochondrial fission and fusion by Ezrin was confirmed. Overall, celastrol may alleviate AD by regulating Ezrin-mediated mitochondrial fission and fusion, which may become a novel therapeutic reagent for alleviating AD.


Subject(s)
Cytokines , Cytoskeletal Proteins , Dermatitis, Atopic , Mice, Inbred BALB C , Mitochondrial Dynamics , Pentacyclic Triterpenes , Triterpenes , Animals , Mitochondrial Dynamics/drug effects , Pentacyclic Triterpenes/pharmacology , Dermatitis, Atopic/drug therapy , Dermatitis, Atopic/pathology , Dermatitis, Atopic/metabolism , Humans , Triterpenes/pharmacology , Mice , Cytokines/metabolism , Cytoskeletal Proteins/metabolism , Cytoskeletal Proteins/genetics , Thymic Stromal Lymphopoietin , Disease Models, Animal , Mitochondria/metabolism , Mitochondria/drug effects , Reactive Oxygen Species/metabolism , Tumor Necrosis Factor-alpha/metabolism , HaCaT Cells , Phosphorylation/drug effects
9.
Int J Biol Macromol ; 275(Pt 2): 133088, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38880446

ABSTRACT

Flexible composite film has gained increasing attention in the fields of wearable devices and portable electronic products. In this work, a novel core-shell structure of cellulose nanofibers/BaTiO3@TiO2 (CNF/BTO@TiO2) was synthesized with the assistant of the biological macromolecule material of cellulose nanofiber (CNF), in which the CNF can improve the stability and dispersibility of BaTiO3 (BTO) in the aqueous phase and elevate the integrity of the core-shell structure. The core-shell structure can reduce the agglomeration of fillers in polyvinylidene fluoride (PVDF) and improve the structural defects of the composite film. Meanwhile, the core-shell structure can promote the polarization of the electric dipole and the formation of ß phase in PVDF due to the generated interface spatial polarization between the shell of TiO2 and the core of BTO. When the content of the core-shell structure was 5 wt%, the ß phase content reaches 61.89 %, and the piezoelectric coefficient of composite film reaches 84.29 pm/V. Thus the maximum output open-circuit voltage (VOC) and short-circuit current (ISC) of the piezoelectric composite film is as high as 13.10 V and 464.3 nA. In addition, its excellent pressure sensing capability allows for its application in various flexible electronic devices.


Subject(s)
Barium Compounds , Cellulose , Nanofibers , Polyvinyls , Titanium , Titanium/chemistry , Nanofibers/chemistry , Polyvinyls/chemistry , Barium Compounds/chemistry , Cellulose/chemistry , Electricity , Fluorocarbon Polymers
10.
Int Dent J ; 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38866671

ABSTRACT

OBJECTIVES: With rising rates of maxillofacial fracture, postoperative infection following rigid internal fixation is an important issue that requires immediate resolution. It is important to explore an alternative antibacterial method apart from conventional antibiotics. A controlled experiment was conducted to evaluate the effectiveness of a caerin 1.9 peptide-coated titanium plate in reducing mandibular infection in New Zealand (NZ) rabbits, aiming to minimise the risk of post-metallic implantation infection. METHODS: Twenty-two NZ rabbits were randomly divided into 3 groups. The experiment group received caerin 1.9 peptide-coated titanium plates and mixed oral bacteria exposure. The control group received normal titanium plates with mixed oral bacteria exposure. The untreated group served as a control to prove that bacteria in the mouth can cause infection. Weight, temperature, hepatic function, and C-reactive protein levels were measured. Wound and bone conditions were evaluated. Further analysis included local infection, anatomic conditions, histology, and bacterial load. RESULTS: No significant differences were found in temperature, weight, blood alanine aminotransferase, and C-reactive protein levels amongst the 3 groups. The experiment group showed the lowest amount of bacterial RNA in wounds. Additionally, the experiment group had higher peripheral lymphocyte counts compared to the control group and lower neutrophil counts on the third and seventh day postoperatively. Histologic analysis revealed lower levels of inflammatory cell infiltration, bleeding, and areas of necrosis in the experimental group compared with the controls. CONCLUSIONS: A caerin 1.9-coated titanium plate is able to inhibit bacterial growth in a NZ rabbit mandibular mixed bacteria infection model and is worth further investigation.

11.
Int Dent J ; 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38692963

ABSTRACT

INTRODUCTION AND AIMS: Altering the position and orientation of the root canal access cavity passway, or modifying the reduction of dentin volume, can influence the strength of dentition. This study aimed to compare the effects of different access cavities on the biomechanical performances of maxillary central incisors with a finite element analysis. METHODS: Based on the micro-computed tomography (CT) scan of a maxillary central incisor, the finite element models of the intact tooth and teeth with 4 access cavity designs: conservative incisal access cavity, incisal access cavity, conservative access cavity, and traditional access cavity were generated. Simulated occlusal forces were applied at the incisal edge of the incisor in the finite element analysis procedure. RESULTS: The maximum von Mises stress and maximum principal stress in the cervical area are highest in the traditional access cavity group, followed by the conservative access cavity group, incisal access cavity group, and conservative incisal access cavity group. CONCLUSION: The conservative access cavities minimise the extent of dentin removal from the cervical region, protecting the mechanical behaviour of the incisor. Moving the access cavity entry point to the incisal edge also improves the fracture resistance of the incisor. CLINICAL RELEVANCE: This study's findings would help clinicians select the most appropriate endodontics access cavity method when performing the root canal on maxillary central incisors.

12.
Article in English | MEDLINE | ID: mdl-38598095

ABSTRACT

Ochratoxin A (OTA) is a toxic fungal metabolite that is commonly found in cereals and animal feed. It is economically damaging and potentially hazardous to human health. Herein, we propose an electrochemical immunosensor for the rapid detection of OTA using anti-OTA antibodies and diazonium-functionalized, screen-printed electrodes. We attached 4-aminobenzoic acid to an electrode surface, activated the carboxyl groups on the surface with carbodiimide, and attached an antibody to the diazo layer. Subsequently, we used bovine serum protein as a blocker to prevent non-specific antigens from binding to the antibody. We evaluated the performance of the sensor by cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. The sensor is highly specific and sensitive, has good linear responses in the range 20-200 ng/mL, a limit of detection of 0.5 ng/mL, and good recoveries of 90.5%-100.9% in spiked samples. It can be stored at 4 °C for approximately 2 weeks, and is highly stable, with a current response variation of no more than 4.6%.


Subject(s)
Electrochemical Techniques , Food Contamination , Ochratoxins , Ochratoxins/analysis , Food Contamination/analysis , Electrodes , Immunoassay/methods , Food Analysis , Diazonium Compounds/chemistry , Biosensing Techniques , Animals
13.
Adv Sci (Weinh) ; 11(21): e2308491, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38466927

ABSTRACT

Peptide and protein postmodification have gained significant attention due to their extensive impact on biomolecule engineering and drug discovery, of which cysteine-specific modification strategies are prominent due to their inherent nucleophilicity and low abundance. Herein, the study introduces a novel approach utilizing multifunctional 5-substituted 1,2,3-triazine derivatives to achieve multifaceted bioconjugation targeting cysteine-containing peptides and proteins. On the one hand, this represents an inaugural instance of employing 1,2,3-triazine in biomolecular-specific modification within a physiological solution. On the other hand, as a powerful combination of precision modification and biorthogonality, this strategy allows for the one-pot dual-orthogonal functionalization of biomolecules utilizing the aldehyde group generated simultaneously. 1,2,3-Triazine derivatives with diverse functional groups allow conjugation to peptides or proteins, while bi-triazines enable peptide cyclization and dimerization. The examination of the stability of bi-triazines revealed their potential for reversible peptide modification. This work establishes a comprehensive platform for identifying cysteine-selective modifications, providing new avenues for peptide-based drug development, protein bioconjugation, and chemical biology research.


Subject(s)
Cysteine , Peptides , Proteins , Triazines , Cysteine/chemistry , Triazines/chemistry , Peptides/chemistry , Proteins/chemistry
14.
Nat Commun ; 15(1): 2797, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38555355

ABSTRACT

Silent information regulator 2 (Sir2) proteins typically catalyze NAD+-dependent protein deacetylation. The recently identified bacterial Sir2 domain-containing protein, defense-associated sirtuin 2 (DSR2), recognizes the phage tail tube and depletes NAD+ to abort phage propagation, which is counteracted by the phage-encoded DSR anti-defense 1 (DSAD1), but their molecular mechanisms remain unclear. Here, we determine cryo-EM structures of inactive DSR2 in its apo form, DSR2-DSAD1 and DSR2-DSAD1-NAD+, as well as active DSR2-tube and DSR2-tube-NAD+ complexes. DSR2 forms a tetramer with its C-terminal sensor domains (CTDs) in two distinct conformations: CTDclosed or CTDopen. Monomeric, rather than oligomeric, tail tube proteins preferentially bind to CTDclosed and activate Sir2 for NAD+ hydrolysis. DSAD1 binding to CTDopen allosterically inhibits tube binding and tube-mediated DSR2 activation. Our findings provide mechanistic insight into DSR2 assembly, tube-mediated DSR2 activation, and DSAD1-mediated inhibition and NAD+ substrate catalysis in bacterial DSR2 anti-phage defense systems.


Subject(s)
Sirtuins , Sirtuins/metabolism , NAD/metabolism , Silent Information Regulator Proteins, Saccharomyces cerevisiae/metabolism , Sirtuin 2 , Hydrolysis
15.
Front Public Health ; 12: 1320146, 2024.
Article in English | MEDLINE | ID: mdl-38420033

ABSTRACT

Objective: During the COVID-19 pandemic, people posted help-seeking messages on Weibo, a mainstream social media in China, to solve practical problems. As viruses, policies, and perceptions have all changed, help-seeking behavior on Weibo has been shown to evolve in this paper. Methods: We compare and analyze the help-seeking messages from three dimensions: content categories, time distribution, and retweeting influencing factors. First, we crawled the help-seeking messages from Weibo, and successively used CNN and xlm-roberta-large models for text classification to analyze the changes of help-seeking messages in different stages from the content categories dimension. Subsequently, we studied the time distribution of help-seeking messages and calculated the time lag using TLCC algorithm. Finally, we analyze the changes of the retweeting influencing factors of help-seeking messages in different stages by negative binomial regression. Results: (1) Help-seekers in different periods have different emphasis on content. (2) There is a significant correlation between new daily help-seeking messages and new confirmed cases in the middle stage (1/1/2022-5/20/2022), with a 16-day time lag, but there is no correlation in the latter stage (12/10/2022-2/25/2023). (3) In all the periods, pictures or videos, and the length of the text have a significant positive effect on the number of retweets of help-seeking messages, but other factors do not have exactly the same effect on the retweeting volume. Conclusion: This paper demonstrates the evolution of help-seeking messages during different stages of the COVID-19 pandemic in three dimensions: content categories, time distribution, and retweeting influencing factors, which are worthy of reference for decision-makers and help-seekers, as well as provide thinking for subsequent studies.


Subject(s)
COVID-19 , Social Media , Humans , COVID-19/epidemiology , Pandemics , SARS-CoV-2 , China/epidemiology
16.
J Org Chem ; 89(3): 1681-1691, 2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38207100

ABSTRACT

Pyrene-based derivatives have been widely deployed in organic luminescent materials because of their bright fluorescence, high charge carrier mobility, and facile modification. Nevertheless, the fluorescence output of conventional pyrenes is prone to quenching upon aggregation due to extensive intermolecular π-π stacking interactions. To address this issue, a set of new Y-shaped pyrene-containing luminogens are synthesized from a new bromopyrene chemical precursor, 2-hydroxyl-7-tert-butyl-1,3-bromopyrene, where the bromo and hydroxyl groups at the pyrene core can be readily modified to obtain the target products and provide great flexibility in tuning the photophysical performances. When the hydroxy group at the 2-position of pyrene was replaced by a benzyl group, the steric hindrance of the benzyl group not only efficiently inhibits the detrimental intermolecular π-π stacking interactions but also rigidifies the molecular conformation, resulting in a narrow-band blue emission. Moreover, the TPE-containing compounds 2c and 3c possessed characteristic aggregation-induced emission (AIE) properties with fluorescence quantum yields of up to 66% and 38% in the solid state, respectively. Thus, this article has methodically investigated the factors influencing the optical behavior, such as intermolecular interactions, and the steric effects of the substituent group, thereby opening up the potential to develop narrow-band pyrene-based blue emitters for OLED device applications.

17.
Glob Health Res Policy ; 8(1): 53, 2023 12 18.
Article in English | MEDLINE | ID: mdl-38105284

ABSTRACT

Primary health care (PHC) is the most effective way to improve people's health and well-being, and primary care services should act as the cornerstone of a resilient health system and the foundation of universal health coverage. To promote high quality development of PHC, an International Symposium on Quality Primary Health Care Development was held on December 4-5, 2023 in Beijing, China, and the participants have proposed and advocated the Beijing Initiative on Quality Primary Health Care Development. The Beijing Initiative calls on all countries to carry out and strengthen 11 actions: fulfill political commitment and accountability; achieve "health in all policies" through multisectoral coordination; establish sustainable financing; empower communities and individuals; provide community-based integrated care; promote the connection and integration of health services and social services through good governance; enhance training, allocation and motivation of health workforce, and medical education; expand application of traditional and alternative medicine for disease prevention and illness healing; empower PHC with digital technology; ensure access to medicinal products and appropriate technologies; and last, strengthen global partnership and international health cooperation. The Initiative will enrich the content of quality development of PHC, build consensus, and put forward policies for quality development of PHC in China in the new era, which are expected to make contributions in accelerating global actions.


Subject(s)
Primary Health Care , Universal Health Insurance , Humans , Beijing , Delivery of Health Care , Quality of Health Care
18.
Org Lett ; 25(46): 8338-8343, 2023 11 24.
Article in English | MEDLINE | ID: mdl-37966281

ABSTRACT

A visible-light mediated deoxygenative radical addition of carboxylic acids to dehydroalanines has been disclosed. The method can be used in ß-acyl alanine derivative synthesis, including those chiral and deuterated variants, and late-stage peptide modification with various functional groups, both in the homogeneous phase and on the resin in SPPS. It provides a new tool kit for rapid construction of bioactive peptide analogues, which has been demonstrated by modification of the antimicrobial peptide Feleucin-K3.


Subject(s)
Carboxylic Acids , Peptides , Alanine , Photochemistry/methods
19.
J Mater Chem B ; 11(36): 8649-8656, 2023 09 20.
Article in English | MEDLINE | ID: mdl-37623744

ABSTRACT

Charge-transfer (CT) cocrystals consisting of an electron donor and acceptor have gained attention for designing photothermal (PT) conversion materials with potential for biomedical and therapeutic use. However, the applicability of CT cocrystals is limited by their low stability and aqueous dispersity in biological settings. In this study, we present the self-assembly of CT cocrystals within hydrogen-bonded organic frameworks (HOFs), which not only allows for the dispersion and stabilization of cocrystals in aqueous solution but also promotes the CT interaction within the confined space of HOFs for photothermal conversion. We demonstrate that the CT interaction-driven self-assembly of tetrathiafulvalene (TTF) and tetracyanoquinodimethane (TCNQ) with PFC-1 HOFs results in the formation of cocrystal-encapsulated TQC@PFC-1 while retaining the crystalline structure of the cocrystal and PFC-1. TQC@PFC-1, in particular, exhibits significant absorption in the second near-infrared region (NIR-II) and excellent photothermal conversion efficiency, as high as 32%. Cellular delivery studies show that TQC@PFC-1 can be internalized in different types of cancer cells, leading to an effective NIR-II photothermal therapy effect both in cultured cells and in vivo. We anticipate that the strategy of self-assembly and stabilization of CT cocrystals in nanoscale HOFs opens the path for tuning their photophysical properties and interfacing cocrystals with biological settings for photothermal therapeutic applications.


Subject(s)
Neoplasms , Photothermal Therapy , Humans , Neoplasms/drug therapy , Hydrogen
20.
ACS Appl Mater Interfaces ; 15(31): 37580-37592, 2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37490285

ABSTRACT

The concept of triboelectric nanogenerator (TENG)-based fibrous air filters, in which the electroactive fibers are ready to enhance the electrostatic adsorption by sustainable energy harvesting, is appealing for long-term respiratory protection and in vivo real-time monitoring. This effort discloses a self-reinforcing electroactivity strategy to confer extreme alignment and refinement of the electrospun poly(lactic acid) (PLA) nanofibers, significantly facilitating formation of electroactive phases (i.e., ß-phase and highly aligned chains and dipoles) and promotion of polarization and electret properties. It endowed the PLA nanofibrous membranes (NFMs) with largely increased surface potential and filtration performance, as exemplified by efficient removal of PM0.3 and PM2.5 (90.68 and 99.82%, respectively) even at the highest airflow capacity of 85 L/min. With high electroactivity and a well-controlled morphology, the PLA NFMs exhibited superior TENG properties triggered by regular respiratory vibrations, enabling 9.21-fold increase of surface potential (-1.43 kV) and nearly 68% increase of PM0.3 capturing (94.3%) compared to those of conventional PLA membranes. The remarkable TENG mechanisms were examined to elaborately monitor the personal respiration characteristics, particularly those triggered large and rapid variations of output voltages like coughing and tachypnea. Featuring desirable biocompatibility and degradability, the self-powered PLA NFMs permit promising applications in the fabrication of ecofriendly air filters toward high-performance purification and intelligent monitoring.


Subject(s)
Air Filters , Nanofibers , Respiratory Rate , Filtration , Polyesters
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