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Performing data augmentation in medical named entity recognition (NER) is crucial due to the unique challenges posed by this field. Medical data is characterized by high acquisition costs, specialized terminology, imbalanced distributions, and limited training resources. These factors make achieving high performance in medical NER particularly difficult. Data augmentation methods help to mitigate these issues by generating additional training samples, thus balancing data distribution, enriching the training dataset, and improving model generalization. This paper proposes two data augmentation methods-Contextual Random Replacement based on Word2Vec Augmentation (CRR) and Targeted Entity Random Replacement Augmentation (TER)-aimed at addressing the scarcity and imbalance of data in the medical domain. When combined with a deep learning-based Chinese NER model, these methods can significantly enhance performance and recognition accuracy under limited resources. Experimental results demonstrate that both augmentation methods effectively improve the recognition capability of medical named entities. Specifically, the BERT-BiLSTM-CRF model achieved the highest F1 score of 83.587%, representing a 1.49% increase over the baseline model. This validates the importance and effectiveness of data augmentation in medical NER.
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Aprendizaje Profundo , Humanos , Procesamiento de Lenguaje NaturalRESUMEN
BACKGROUND AND AIMS: Vascular smooth muscle cell (VSMC) senescence is crucial for the development of atherosclerosis, characterized by metabolic abnormalities. Tumour necrosis factor receptor-associated protein 1 (TRAP1), a metabolic regulator associated with ageing, might be implicated in atherosclerosis. As the role of TRAP1 in atherosclerosis remains elusive, this study aimed to examine the function of TRAP1 in VSMC senescence and atherosclerosis. METHODS: TRAP1 expression was measured in the aortic tissues of patients and mice with atherosclerosis using western blot and RT-qPCR. Senescent VSMC models were established by oncogenic Ras, and cellular senescence was evaluated by measuring senescence-associated ß-galactosidase expression and other senescence markers. Chromatin immunoprecipitation (ChIP) analysis was performed to explore the potential role of TRAP1 in atherosclerosis. RESULTS: VSMC-specific TRAP1 deficiency mitigated VSMC senescence and atherosclerosis via metabolic reprogramming. Mechanistically, TRAP1 significantly increased aerobic glycolysis, leading to elevated lactate production. Accumulated lactate promoted histone H4 lysine 12 lactylation (H4K12la) by down-regulating the unique histone lysine delactylase HDAC3. H4K12la was enriched in the senescence-associated secretory phenotype (SASP) promoter, activating SASP transcription and exacerbating VSMC senescence. In VSMC-specific Trap1 knockout ApoeKO mice (ApoeKOTrap1SMCKO), the plaque area, senescence markers, H4K12la, and SASP were reduced. Additionally, pharmacological inhibition and proteolysis-targeting chimera (PROTAC)-mediated TRAP1 degradation effectively attenuated atherosclerosis in vivo. CONCLUSIONS: This study reveals a novel mechanism by which mitonuclear communication orchestrates gene expression in VSMC senescence and atherosclerosis. TRAP1-mediated metabolic reprogramming increases lactate-dependent H4K12la via HDAC3, promoting SASP expression and offering a new therapeutic direction for VSMC senescence and atherosclerosis.
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Endothelial-to-mesenchymal transition (EndMT) is a key driver of atherosclerosis. Aerobic glycolysis is increased in the endothelium of atheroprone areas, accompanied by elevated lactate levels. Histone lactylation, mediated by lactate, can regulate gene expression and participate in disease regulation. However, whether histone lactylation is involved in atherosclerosis remains unknown. Here, we report that lipid peroxidation could lead to EndMT-induced atherosclerosis by increasing lactate-dependent histone H3 lysine 18 lactylation (H3K18la) in vitro and in vivo, as well as in atherosclerotic patients' arteries. Mechanistically, the histone chaperone ASF1A was first identified as a cofactor of P300, which precisely regulated the enrichment of H3K18la at the promoter of SNAI1, thereby activating SNAI1 transcription and promoting EndMT. We found that deletion of ASF1A inhibited EndMT and improved endothelial dysfunction. Functional analysis based on Apoe KO Asf1a ECKO mice in the atherosclerosis model confirmed the involvement of H3K18la in atherosclerosis and found that endothelium-specific ASF1A deficiency inhibited EndMT and alleviated atherosclerosis development. Inhibition of glycolysis by pharmacologic inhibition and advanced PROTAC attenuated H3K18la, SNAI1 transcription, and EndMT-induced atherosclerosis. This study illustrates precise crosstalk between metabolism and epigenetics via H3K18la by the P300/ASF1A molecular complex during EndMT-induced atherogenesis, which provides emerging therapies for atherosclerosis.
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Industrial wastewater containing heavy metal Cr(VI) seriously affects the health of organisms and may even lead to cancer. Developing efficient adsorbents that can quickly separate heavy metals is crucial for treating wastewater. In this study, magnetic multiwalled carbon nanotubes (MMWCNTs) with moderate particle size and abundant surface active sites were prepared by coating multiwalled carbon nanotubes with magnetic nanoparticles. The results of FTIR, XRD, TG, VSM, BET, and EDS showed MWCNTs completely encapsulated on the surface of the magnetic nanoparticles, with a particle size of approximately 30 nm. Oxygenated groups provided abundant surface active sites and formed numerous mesopores. The response surface methodology was used to optimize the adsorbent dose, adsorption contact time and adsorption temperature, and the removal rate of Cr(VI) was more than 95%. The quasi-second order kinetics and Freundlich adsorption isotherm model explained the adsorption process to Cr(VI). MMWCNTs interacted with Cr(VI) through electrostatic attraction, reduction reactions, complexation, and other means. The extensive hydrogen bonding of the green solvent deep eutectic solvent (DES) was employed to desorb the MMWCNTs and desorption rate exceed 90%. Even after five adsorption-regeneration cycles, the adsorbent maintained a high capacity. In conclusion, these novel MMWCNTs, as efficient adsorbents paired with DES desorption, hold broad potential for application in the treatment of Cr(VI)-contaminated wastewater.
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Cromo , Disolventes Eutécticos Profundos , Nanotubos de Carbono , Aguas Residuales , Contaminantes Químicos del Agua , Nanotubos de Carbono/química , Cromo/química , Cromo/aislamiento & purificación , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Adsorción , Cinética , Disolventes Eutécticos Profundos/química , Purificación del Agua/métodos , Eliminación de Residuos Líquidos/métodosRESUMEN
Macrophage activation is a hallmark of atherosclerosis, accompanied by a switch in core metabolism from oxidative phosphorylation to glycolysis. The crosstalk between metabolic rewiring and histone modifications in macrophages is worthy of further investigation. Here, we find that lactate efflux-associated monocarboxylate transporter 4 (MCT4)-mediated histone lactylation is closely related to atherosclerosis. Histone H3 lysine 18 lactylation dependent on MCT4 deficiency activated the transcription of anti-inflammatory genes and tricarboxylic acid cycle genes, resulting in the initiation of local repair and homeostasis. Strikingly, histone lactylation is characteristically involved in the stage-specific local repair process during M1 to M2 transformation, whereas histone methylation and acetylation are not. Gene manipulation and protein hydrolysis-targeted chimerism technology are used to confirm that MCT4 deficiency favors ameliorating atherosclerosis. Therefore, our study shows that macrophage MCT4 deficiency, which links metabolic rewiring and histone modifications, plays a key role in training macrophages to become repair and homeostasis phenotypes.
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Aterosclerosis , Histonas , Lisina , Macrófagos , Transportadores de Ácidos Monocarboxílicos , Histonas/metabolismo , Macrófagos/metabolismo , Aterosclerosis/metabolismo , Aterosclerosis/genética , Aterosclerosis/patología , Animales , Ratones , Transportadores de Ácidos Monocarboxílicos/metabolismo , Transportadores de Ácidos Monocarboxílicos/genética , Lisina/metabolismo , Humanos , Proteínas Musculares/metabolismo , Proteínas Musculares/genética , Activación de Macrófagos , Ratones Endogámicos C57BLRESUMEN
Glycolysis-dominant metabolic pathway in cancer cells can promote their therapeutic resistance against radiotherapy (RT). Carbon monoxide (CO) as a glycolysis inhibitor can enhance the efficiency of RT. Herein, an X-ray responsive CO-releasing nanocomposite (HA@AuNC@CO) based on strong host-guest interactions between the radiosensitizer and CO donor for enhanced RT is developed. The encapsulated gold nanoclusters (CD-AuNCs) can effectively generate cytotoxic reactive oxygen species (ROS) under X-ray radiation, which not only directly inactivate cancer cells but also induce in situ CO gas generation from adamantane modified metal carbonyl (Ada-CO) for glycolysis inhibition. Both in vitro and in vivo results demonstrate that HA@AuNC@CO exhibits active targeting toward CD44 overexpressed cancer cells, along with excellent inhibition of glycolysis and efficient RT against cancer. This study offers a new strategy for the combination of gas therapy and RT in tumor treatment.
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Monóxido de Carbono , Glucólisis , Oro , Nanopartículas del Metal , Especies Reactivas de Oxígeno , Oro/química , Monóxido de Carbono/química , Humanos , Animales , Nanopartículas del Metal/química , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Rayos X , Glucólisis/efectos de los fármacos , Ratones , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Neoplasias/metabolismo , Fármacos Sensibilizantes a Radiaciones/química , Fármacos Sensibilizantes a Radiaciones/farmacologíaRESUMEN
Endothelial dysfunction is an initiating factor in atherosclerosis. Endothelial cells (ECs) are constantly subject to blood flow shear stress, and atherosclerotic plaques tend to occur in aortic bends or bifurcations impaired by low oscillatory shear stress (OSS). However, the mechanism that how OSS affects the initiation and progression of atherosclerosis remains to be explored. Here, we first reported that OSS can promote endothelial dysfunction and atherogenesis in vivo and in vitro by activating STING pathway. Mechanistically, at atherosclerosis-prone areas, OSS caused mitochondria damage in ECs, leading to the leakage of mitochondrial DNA (mtDNA) into the cytoplasm. The cytoplasmic mtDNA was recognized by cGAS to produce cGAMP, activating the STING pathway and leading to endothelial senescence, which resulted in endothelial dysfunction and atherosclerosis. We found that STING was activated in plaques of atherosclerotic patients and in aortic arch ECs of high-fat diet (HFD)-fed ApoeKO mice, as well as in ECs exposed to OSS. STING-specific deficiency in ECs attenuates endothelial senescence and resulted in a significant reduction in aortic arch plaque area in HFD-fed ApoeKO mice. Consistently, specific deficiency or pharmacological inhibition of STING attenuated OSS-induced senescence and endothelial dysfunction. Pharmacological depletion of mtDNA ameliorated OSS-induced senescence and endothelial dysfunction. Taken together, our study linked hemodynamics and endothelial senescence, and revealed a novel mechanism by which OSS leads to endothelial dysfunction. Our study provided new insights into the development of therapeutic strategies for endothelial senescence and atherosclerosis.
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Aterosclerosis , Senescencia Celular , Células Endoteliales , Proteínas de la Membrana , Estrés Mecánico , Animales , Humanos , Ratones , Aterosclerosis/metabolismo , Aterosclerosis/patología , Aterosclerosis/genética , Células Cultivadas , Senescencia Celular/genética , Dieta Alta en Grasa , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Células Endoteliales/metabolismo , Células Endoteliales/patología , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Ratones Endogámicos C57BL , Mitocondrias/metabolismo , Mitocondrias/patologíaRESUMEN
The standard treatment for early-stage breast cancer involves breast-conserving surgery followed by adjuvant radiotherapy. However, approximately 20 % of patients experience distant metastasis, and adjuvant radiotherapy often leads to radiation-induced skin fibrosis (RISF). In this study, we develop an on-site injectable formulation composed of selenocystamine (SeCA) and hyaluronic acid (HyA), referred to as SeCA cross-linked HyA (SCH) agent, and investigate its potential to mitigate metastasis and prevent RISF associated with breast cancer therapy. SCH agents are synthesized using the nanoprecipitation method to modulate cell-cell tight junctions and tissue inflammation. The toxicity assessments reveal that SCH agents with a higher Se content (Se payload 17.4 µg/mL) are well tolerated by L929 cells compared to SeCA (Se payload 3.2 µg/mL). In vitro, SCH agents significantly enhance cell-cell tight junctions and effectively mitigate migration and invasion of breast cancer cells (4T1). In vivo, SCH agents mitigate distant lung metastasis. Furthermore, in animal models, SCH agents reduce RISF and promote wound repair. These findings highlight the potential of SCH agents as a novel therapeutic formulation for effectively mitigating metastasis and reducing RISF. This holds great promise for improving clinical outcomes in breast cancer patients undergoing adjuvant radiotherapy.
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Neoplasias de la Mama , Fibrosis , Ácido Hialurónico , Ácido Hialurónico/química , Animales , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Ratones , Fibrosis/tratamiento farmacológico , Línea Celular Tumoral , Humanos , Ratones Endogámicos BALB C , Cistamina/química , Cistamina/farmacología , Piel/efectos de los fármacos , Piel/patología , Piel/efectos de la radiación , Movimiento Celular/efectos de los fármacos , InyeccionesRESUMEN
PURPOSE: Persistent descending mesocolon (PDM) increases the difficulty and colonic ischemia in the surgery of colorectal cancer, but the preoperative diagnostic criteria have not yet been clearly demonstrated. This study explored the MR imaging features and diagnostic criteria of PDM to improve the preoperative diagnostic rate. METHODS: The clinical data of 54 patients with PDM and 270 patients without PDM who underwent rectal surgery at the Department of Colorectal Surgery, Fujian Medical University Union Hospital, from March 2018 to December 2022 were analyzed, retrospectively. The radiological parameters of PDM from MRI were analyzed. RESULTS: On MRI T2WI axial image, the left edge of the abdominal aorta was defined as the reference line. The shortest vertical distance between the right edge of the descending colon and this line (dN) and the maximum transverse diameter of the peritoneal cavity (dA) at the same level and the maximum vertical distance between the right edge of the descending colon and this line (dW) were measured. There were significant statistical differences in dN, dW, dN/dW, and dN/dA between the PDM group and the non-PDM group. dN, dN/dW, and dN/dA have high diagnostic performance for the PDM. dN < 4.16 cm, dN/dW < 0.52, and dN/dA < 0.15 can all be used as clues to diagnose PDM. CONCLUSIONS: We propose a feasible set of diagnostic criteria for PDM based on abdominal MRI, which can quickly and accurately diagnose PDM, and provide some reference for preoperative planning and surgical decision-making.
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Laparoscopía , Mesocolon , Neoplasias del Recto , Humanos , Mesocolon/diagnóstico por imagen , Mesocolon/cirugía , Estudios Retrospectivos , Laparoscopía/métodos , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/cirugía , Cavidad PeritonealRESUMEN
BACKGROUND: Senescence is a series of degenerative changes in the structure and physiological function of an organism. Whether JPX (just proximal to XIST)-a newly identified age-related noncoding RNA by us-is associated with atherosclerosis is still unknown. Our study was to investigate the role of JPX and provide insights into potential therapies targeting atherosclerosis. METHODS: We analyzed clinical data from multiple tissues including meniscus tissue, leukemia cells, and peripheral blood monocytes to identify age-related noncoding RNAs in senescent vascular smooth muscle cells (VSMCs). The molecular mechanism of JPX was investigated by capture hybridization analysis of RNA targets and chromatin immunoprecipitation. IGVTools and real-time quantitative polymerase chain reaction were used to evaluate the JPX expression during phenotype regulation in age-related disease models. The therapeutic potential of JPX was evaluated after establishing an atherosclerosis model in smooth muscle-specific Jpx knockout mice. RESULTS: JPX expression was upregulated in activated ras allele (H-rasV12)-induced senescent VSMCs and atherosclerotic arteries. JPX knockdown substantially reduced the elevation of senescence-associated secretory phenotype (SASP) genes in senescent VSMCs. Cytoplasmic DNA leaked from mitochondria via mitochondrial permeability transition pore formed by VDAC1 (voltage-dependent anion channel 1) oligomer activates the STING (stimulator of interferon gene) pathway. JPX could act as an enhancer for the SASP genes and functions as a scaffold molecule through interacting with phosphorylated p65/RelA and BRD4 (bromodomain-containing protein 4) in chromatin remodeling complex, promoting the transcription of SASP genes via epigenetic regulation. Smooth muscle knockout of Jpx in ApoeKO mice resulted in a decrease in plaque area, a reduction in SASP gene expression, and a decrease in senescence compared with controls. CONCLUSIONS: As an enhancer RNA, JPX can integrate p65 and BRD4 to form a chromatin remodeling complex, activating SASP gene transcription and promoting cellular senescence. These findings suggest that JPX is a potential therapeutic target for the treatment of age-related atherosclerosis.
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Aterosclerosis , ARN Largo no Codificante , Ratones , Animales , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Músculo Liso Vascular/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Cromatina , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Epigénesis Genética , Aterosclerosis/genética , Aterosclerosis/metabolismo , Senescencia Celular/genética , Ratones Noqueados , Miocitos del Músculo Liso/metabolismoRESUMEN
OBJECTIVES: Although observational studies have reported the association between frailty and mental disorders, the causality remains unclear. We aimed to evaluate the bidirectional causal association between frailty levels and mental disorders using a 2-sample Mendelian randomization (MR) analysis. DESIGN: A bidirectional, 2-sample Mendelian randomization (MR) analysis. SETTING AND PARTICIPANTS: Instrumental variables were obtained from large-scale genome-wide association study (GWAS) of a European-descent population for frailty index (FI, n = 175,226), Fried Frailty Score (FFS, n = 386,565), major depressive disorder (MDD, n = 674,452), bipolar disorder (n = 353,899), anxiety and stress-related disorder (ASRD, n = 31,880), and schizophrenia (n = 127,906). METHODS: Two-sample MR analyses were conducted using inverse variance-weighted method, with sensitivity analyses using MR-Egger, weighted median, and simple median methods. RESULTS: Per SD increase in genetically predicted FI and FFS increased the risk of MDD [odds ratio (OR) 1.56, 95% CI 1.27-1.94, P = 3.65 × 10-5, and OR 1.67, 95% CI 1.26-2.20, P = 3.02 × 10-4, respectively]. Per-SD increase in genetically predicted FI also increased the risk of ASRD (OR 2.76, 95% CI 1.36-5.60, P = .005). No significant effect was observed for frailty levels on the risk of bipolar disorder and schizophrenia. In the reverse direction, genetically predicted MDD was associated with higher FI (ß 0.182, 95% CI 0.087-0.277, P = 1.79 × 10-4) and FFS (ß 0.121, 95% CI 0.087-0.155, P = 4.43 × 10-12). No reliable evidence supported the effects of genetically predicted bipolar disorder, ASRD, or schizophrenia on frailty levels. CONCLUSIONS AND IMPLICATIONS: A bidirectionally causal association exists between frailty levels and MDD, and higher FI is associated with a higher risk of ASRD. No reliable evidence suggested the causal associations of other mental disorders with frailty. Our findings provided evidence for introduction of psychological-related strategies in management of frailty.
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Trastorno Depresivo Mayor , Fragilidad , Trastornos Mentales , Humanos , Trastorno Depresivo Mayor/epidemiología , Trastorno Depresivo Mayor/genética , Fragilidad/genética , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Trastornos Mentales/epidemiología , Trastornos Mentales/genéticaRESUMEN
With the increasing demands of X-ray detection and medical diagnosis, organic scintillators with intense and tunable X-ray excited emission have been becoming important. To guarantee the X-ray absorption, heavy atoms were widely added in reported organic scintillators, which led to emission quenching. In this work, we propose a new strategy to realize organic scintillators through the host-guest doping strategy. Then the X-ray absorption centers (host) and emission centers (guest) are separated. Under X-ray excitation, these materials displayed intense and readily tunable emissions ranging from green (520â nm) to near infrared (NIR) regions (682â nm). Besides, the relationship between the X-ray absorption and spatial arrangement of the heavy atoms in the host matrix was also revealed. The potential application of these wide-range color tunable organic host-guest scintillators in X-ray imaging were demonstrated. This work provides a new feasible strategy for constructing high-performance organic scintillators with tunable luminescence properties.
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Inflammation-driven endothelial dysfunction is the major initiating factor in atherosclerosis, while the underlying mechanism remains elusive. Here, we report that the non-canonical stimulator of interferon genes (STING)-PKR-like ER kinase (PERK) pathway was significantly activated in both human and mice atherosclerotic arteries. Typically, STING activation leads to the activation of interferon regulatory factor 3 (IRF3) and nuclear factor-kappa B (NF-κB)/p65, thereby facilitating IFN signals and inflammation. In contrast, our study reveals the activated non-canonical STING-PERK pathway increases scaffold protein bromodomain protein 4 (BRD4) expression, which encourages the formation of super-enhancers on the proximal promoter regions of the proinflammatory cytokines, thereby enabling the transactivation of these cytokines by integrating activated IRF3 and NF-κB via a condensation process. Endothelium-specific STING and BRD4 deficiency significantly decreased the plaque area and inflammation. Mechanistically, this pathway is triggered by leaked mitochondrial DNA (mtDNA) via mitochondrial permeability transition pore (mPTP), formed by voltage-dependent anion channel 1 (VDAC1) oligomer interaction with oxidized mtDNA upon cholesterol oxidation stimulation. Especially, compared to macrophages, endothelial STING activation plays a more pronounced role in atherosclerosis. We propose a non-canonical STING-PERK pathway-dependent epigenetic paradigm in atherosclerosis that integrates IRF3, NF-κB and BRD4 in inflammatory responses, which provides emerging therapeutic modalities for vascular endothelial dysfunction.
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Both sulfonyl and phosphorothioate are important privileged structural motifs which are widely presented in pharmaceuticals and agrochemicals. Herein, we describe an efficient approach to synthesizing sulfonyl-containing phosphorothioates by merging photoredox and copper catalysis at room temperature. This protocol is compatible with a wide range of substrates and can be applied to the late-stage modification of complex molecules. Control experiments are conducted to demonstrate the generation of the sulfonyl radical in the transformation.
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Purpose: Glioblastoma is a highly aggressive brain tumor with universally poor outcomes. Recent progress in immune checkpoint inhibitors has led to increased interest in their application in glioblastoma. Nonetheless, the unique immune milieu in the brain has posed remarkable challenges to the efficacy of immunotherapy. We aimed to leverage the radiation-induced immunogenic cell death to overcome the immunosuppressive network in glioblastoma. Methods: We developed a novel approach using the gold-core silica-shell nanoparticles (Au@SiO2 NPs) in combination with low-dose radiation to enhance the therapeutic efficacy of the immune checkpoint inhibitor (atezolizumab) in brain tumors. The biocompatibility, immune cell recruitment, and antitumor ability of the combinatorial strategy were determined using in vitro assays and in vivo models. Results: Our approach successfully induced the migration of macrophages towards brain tumors and promoted cancer cell apoptosis. Subcutaneous tumor models demonstrated favorable safety profiles and significantly enhanced anticancer effects. In orthotopic brain tumor models, the multimodal therapy yielded substantial prognostic benefits over any individual modalities, achieving an impressive 40% survival rate. Conclusion: In summary, the combination of Au@SiO2 NPs and low-dose radiation holds the potential to improve the clinical efficacy of immune checkpoint inhibitors. The synergetic strategy modulates tumor microenvironments and enhances systemic antitumor immunity, paving a novel way for glioblastoma treatment.
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Neoplasias Encefálicas , Glioblastoma , Nanopartículas , Humanos , Dióxido de Silicio/uso terapéutico , Glioblastoma/tratamiento farmacológico , Oro/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/tratamiento farmacológico , Línea Celular Tumoral , Microambiente TumoralRESUMEN
To accurately determine flavonoids (rutin, quercetin or kaempferol), it is necessary to extract them from complex matrices. The ultrasound-assisted magnetic dispersion microsolid phase extraction technique has been predominantly used for separation and enrichment of the target analytes. The combination of magnetic chitosan nanoparticles and a deep eutectic supramolecular solvent (DESP) is likely to enhance the efficiency of flavonoid extraction from food. In this study, adsorbents were prepared by modifying chitosan with magnetic nanoparticles, and the eluent was a DESP derived from ß-cyclodextrin and an organic acid. The successful preparation of these materials was confirmed by FTIR, XRD, FE-SEM and 1H NMR. The extraction recovery rates exceeded 93 %, with limits of detection and quantitation ranging from 0.9 to 2.4 µg/L and 2.7 to 7.2 µg/L, respectively, and the flavonoid clearance rates for ABTS and DPPH radicals reached 100 %. Therefore, the integration of magnetic chitosan nanoparticles with the DESP provides a new and efficient method for the extraction of flavonoids while also presenting a potential application of the DESP in separations.
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Quitosano , Nanopartículas de Magnetita , beta-Ciclodextrinas , Flavonoides , QuercetinaRESUMEN
A combination of magnetic κ-carrageenan nanoparticles and deep eutectic supramolecular solvents used for extraction of catechol from water was evaluated by the magnetic dispersion solid phase extraction method. The magnetic κ-carrageenan nanoparticles (KC@Fe3O4MNPs) and the deep eutectic supramolecular solvent (DESP) were characterised by 1H NMR, FT-IR, XRD, SEM, VSM, TG, and BET. The adsorption kinetics, adsorption isothermal model, adsorption thermodynamics and effects of pH and salt concentration were investigated. Additionally, the factors used in the desorption process, such as the type, dosage, concentration and time, were analysed. Under the optimised conditions, the analytes were linear over the range 5-5000 ng mL-1, with a correlation coefficient greater than 0.999 and detection and quantitation limits of 1.6 and 4.7 ng mL-1, respectively. The procedure was successfully applied to determinations of the analytes of interest in spiked water samples with relative average recoveries ranging from 94.3% to 101.5%. These results indicated that the combination of functionalized magnetic nanoparticles and DESP had high specificity and extraction efficiency for catechol and will be a feasible alternative to conventional analyses of organic phenolic pollutants in water.
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Fenómenos Magnéticos , Agua , Agua/química , Carragenina , Espectroscopía Infrarroja por Transformada de Fourier , Solventes/química , Catecoles , Extracción en Fase Sólida/métodos , Límite de DetecciónRESUMEN
The fabrication of an adsorbent with excellent performance has been a focus of attention because of the toxicity, mutagenicity and carcinogenicity of methyl orange (MO)-containing wastewater discharged from the textile, tannery and pharmaceutical industries. In this study, chitosan (CS) membranes were modified with a deep eutectic supramolecular polymer (DESP), and adsorbent membranes with porous structures were prepared with polyethylene glycol (PEG). Microstructural characterization of the CS-DESP-PEG composite membranes with FT-IR, XRD and SEM showed that the membranes had amorphous crystalline structures and that hydrogen bonding interactions weakened the crystallinity and formed loose porous structures. Optimization of the chitosan to ß-cyclodextrin ratio, pH, PEG proportion, MO concentration and adsorbent dose significantly improved the adsorption efficiencies of the membranes. The adsorption behaviours of the membranes were fit with pseudo-second-order adsorption kinetics and the Freundlich adsorption isotherm model. Regeneration experiments showed that the membranes were reusable multiple times and maintained good adsorption capacities.
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Quitosano , Contaminantes Químicos del Agua , Quitosano/química , Adsorción , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier , Cinética , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/químicaRESUMEN
An efficient and metal-free approach for the synthesis of sulfilimines from sulfenamides with aryne and cyclohexyne precursors has been developed. The reaction proceeds through unusual S-C bond formation, which offers a novel and practical entry to access a wide range of sulfilimines in moderate to good yields with excellent chemoselectivity. Moreover, this protocol is amenable to gram-scale synthesis and is applicable to the transformation of the products into useful sulfoximines.
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Iminas , Sulfonamidas/síntesis química , Sulfonamidas/químicaRESUMEN
A novel and efficient S-arylation of sulfenamides with diaryliodonium salts for the synthesis of sulfilimines is developed. The reaction proceeds smoothly under transition-metal-free and air conditions, giving rapid access to sulfilimines in good to excellent yields via selective S-C bond formation. This protocol is scalable and exhibits a broad substrate scope, good functional group tolerance, and excellent chemoselectivity.