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1.
Chemistry ; : e202402078, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976314

RESUMEN

The functionalization of aromatic N-heterocycles through silylium activation demonstrates exceptional selectivity and efficiency. Density functional theory (DFT) calculations unveil the detailed silylium catalysis mechanism and elucidate the origins of selectivity in this reaction. The phosphoramidimidate sulfonamide (PADI) precatalyst orchestrates of the catalytic cycle via three elementary steps. The Brønsted acidity of precatalyst significantly influences both the formation of silylium-based Lewis acid active species and the silylium activation of pyridine. Unlike disulfonimide (DSI)-type precatalysts, both Tf2NH and PADI precatalysts with strong acidities can easily promote the generation of activated silylium pyridine species. A semi-enclosed 'rigid' electronegative cavity in PADI-type anions constructs a well-defined recognition site, facilitating engagement with the positively charged silylium pyridine species. Due to the high electrophilicity and less steric demand at the C4-position of the pyridine substrate, the product with C4-regioselectivity was predominantly generated.

2.
Mater Horiz ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842068

RESUMEN

Intramolecular exciplex systems featuring thermally activated delayed fluorescence (TADF) have garnered significant attention in the realm of organic light-emitting diodes (OLEDs). Nonetheless, the occurrence of organic sandwich intramolecular exciplexes remains rare due to structural limitations and synthetic challenges. Herein, we present a novel rigid acceptor-donor-acceptor (A-D-A) sandwich complex, dSFQP, characterized by two sp3 C-locking moieties. This compound exhibits TADF characteristics facilitated by a multiple through-space charge-transfer process. X-ray crystallographic analysis confirms the distinctive sandwich configuration. The parallel spatial arrangement and minimized A-D-A configuration enhance electronic interactions, resulting in a high photoluminescence quantum yield, rapid reverse intersystem crossing rate, and sluggish nonradiative decay rate. OLEDs employing dSFQP as the dopant achieve a maximum external quantum efficiency (EQE) of 28.5% with a low efficiency roll-off of merely 2.8% at 1000 cd m-2. Even at a high brightness of 10 000 cd m-2, the EQE remains notably high at 17.5%. Our current results provide an effective way to further innovate the design of new organic charge-transfer complexes.

3.
Heliyon ; 10(10): e31450, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38831823

RESUMEN

Ethnopharmacological relevance: Tumour-derived extracellular vesicles (TEVs) have been confirmed to facilitate colorectal cancer (CRC) metastasis by remodelling the tumour microenvironment (TME). Drugs targeted TEVs is considered as a promising therapeutic strategy for cancer treatment. Traditional Chinese medicine (TCM) plays a vital role in improving the prognosis of CRC patients and eventually CRC patients with distant metastasis. Although the anti-tumour effects of active compounds from TCM prescriptions are observed widely, the molecular mechanisms remain unknown. Aim of the study: This study aims to investigate the effects of active compounds in our library of TCM on preventing CRC metastasis, and also explore the potential mechanisms from the perspective of TEVs. Materials and methods: The effects of active compounds on the proliferation of CRC cells were determined by CCK-8 assay. TEVs were extracted from MC38 cells by ultracentrifugation and characterized by electron microscopy, Nanosight NS300 and western blotting. The TEV particles were quantified by Nanosight NS300. The potential mechanism by which astragaloside IV (ASIV) reduced TEV secretion was determined by western blotting. RAW264.7 cells were cocultured with the conditioned medium (CM) of MC38 cells treated with or without ASIV, and the activation of tumour-associated macrophages (TAMs) was assessed by immunofluorescence and quantitative polymerase chain reaction (qPCR). The migration of CRC cells was measured by wound healing and Transwell assay. A spleen-to-liver metastasis model of colorectal cancer was used to confirm the efficiency of ASIV in vivo. Liver metastatic tumours of the mice were used for liver weight measures and H&E staining. Immunofluorescence was applied to observe the infiltration of TAMs, the expression of neutral sphingomyelinase 2 (nSMase2) and Rab27a. Results: By screening our TCM monomer library, we found that ASIV, which is mainly extracted from Radix Astragali, reduced the release of TEVs from CRC cells in a time- and concentration-dependent manner. Mechanistically, ASIV inhibited the production and secretion of TEVs by downregulating nSMase2 and Rab27a expression in CRC cells. CM from ASIV-treated CRC cells reshaped the polarization of TAMs by decreasing M2-type polarization, increasing M1-type polarization. Consequently, the repolarization of M2-type to M1-type macrophages led to reduced invasion and migration of CRC cells. Moreover, we confirmed that ASIV inhibited the liver metastasis of CRC, reduced M2-type macrophage infiltration and decreased the expression of nSMase2 and Rab27a in liver metastases. Conclusions: ASIV inhibited CRC metastasis by reducing EVs release and suppressing M2-type TAMs activation. All these findings reveal a new insight into the mechanisms of ASIV in preventing CRC progression and provide a promising approach for anti-tumour therapy.

4.
J Cell Biochem ; : e30614, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884354

RESUMEN

Currently, the clinical outcomes of peripheral nerve injuries are suboptimal, highlighting the urgent need to understand the mechanisms of nerve injury to enhance treatment strategies. Muscle-derived stem cells (MDSCs) are a diverse group of multipotent cells that hold promise for peripheral nerve regeneration due to their strong antioxidant and regenerative properties. Our research has revealed that severe ferroptosis occurs in the sciatic nerve and ipsilateral dorsal root ganglion following sciatic nerve injury. Interestingly, we have observed that MDSC-derived exosomes effectively suppress cell ferroptosis and enhance cell viability in Schwann cells and dorsal root ganglion cells. Treatment with exosomes led to increased expression of BDNF and P62 in Schwann cells, decreased expression of Keap1, Nrf2, and HO-1 in Schwann cells, and upregulated dorsal root ganglion cells. Rats treated with exosomes exhibited improvements in sciatic nerve function, sensitivity to stimuli, and reduced muscle atrophy, indicating a positive impact on post-injury recovery. In conclusion, our findings demonstrate the occurrence of ferroptosis in the sciatic nerve and dorsal root ganglion post-injury, with MDSC exosomes offering a potential therapeutic strategy by inhibiting ferroptosis, activating the Keap1-Nrf2-HO-1 pathway, and optimizing the post-injury repair environment.

5.
Nat Commun ; 15(1): 4348, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38777853

RESUMEN

The enantioselective synthesis of S-stereogenic sulfinamides has garnered considerable attention due to their structural and physicochemical properties. However, catalytic asymmetric synthesis of sulfinamides still remains daunting challenges, impeding their broad application in drug discovery and development. Here, we present an approach for the synthesis of S-stereogenic sulfinamides through peptide-mimic phosphonium salt-catalyzed asymmetric skeletal reorganization of simple prochiral and/or racemic sulfoximines. This methodology allows for the facile access to a diverse array of substituted sulfinamides with excellent enantioselectivities, accommodating various substituent patterns through desymmetrization or parallel kinetic resolution process. Mechanistic experiments, coupled with density functional theory calculations, clarify a stepwise pathway involving ring-opening and ring-closing processes, with the ring-opening step identified as crucial for achieving stereoselective control. Given the prevalence of S-stereogenic centers in pharmaceuticals, we anticipate that this protocol will enhance the efficient and precise synthesis of relevant chiral molecules and their analogs, thereby contributing to advancements in drug discovery.

6.
Angew Chem Int Ed Engl ; : e202407510, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38774971

RESUMEN

Plastic pollution is an emerging global threat due to lack of effective methods for transforming waste plastics into useful resources. Here, we demonstrate a direct oxidative upcycling of polyethylene into high-value and high-volume saturated dicarboxylic acids in high carbon yield of 85.9 % in which the carbon yield of long chain dicarboxylic (C10-C20) acids can reach 58.9% over cobalt-doped MCM-41 molecular sieves, in the absence of any solvent or precious metal catalyst. The distribution of the dicarboxylic acids can be controllably adjusted from short-chain (C4-C10) to long-chain ones (C10-C20) through changing cobalt loading of MCM-41 under nanoconfinement. Highly and sparsely dispersed cobalt along with confined space of mesoporous structure enables complete degradation of polyethylene and high selectivity of dicarboxylic acid in mild condition. So far, this is the first report on highly selective one-step preparation of long chain dicarboxylic acids. The approach provides an attractive solution to tackle plastic pollution and a promising alternative route to long chain diacids.

7.
J Am Chem Soc ; 146(21): 14864-14874, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38754389

RESUMEN

The exploitation of carbon dioxide (CO2) as a sustainable, plentiful, and harmless C1 source for the catalytic synthesis of enantioenriched carboxylic acids has long been acknowledged as a pivotal task in synthetic chemistry. Herein, we present a current-driven nickel-catalyzed reductive carboxylation reaction with CO2 fixation, facilitating the formation of C(sp3)-C(sp2) bonds by circumventing the handling of moisture-sensitive organometallic reagents. This electroreductive protocol serves as a practical platform, paving the way for the synthesis of enantioenriched propargylic carboxylic acids (up to 98% enantiomeric excess) from racemic propargylic carbonates and CO2. The efficacy of this transformation is exemplified by its successful utilization in the asymmetric total synthesis of (S)-arundic acid, (R)-PIA, (S)-chizhine D, (S)-cochlearin G, and (S,S)-alexidine, thereby underscoring the potential of asymmetric electrosynthesis to achieve complex molecular architectures sustainably.

8.
Food Chem ; 451: 139427, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38692237

RESUMEN

Here, we report a monomer planarity modulation strategy for room-temperature constructing molecularly imprinted-covalent organic frameworks (MI-COFs) for selective extraction of ochratoxin A (OTA). 2,4,6-triformylphloroglucinol (Tp) was used as basic building block, while three amino monomers with different planarity were employed as modulators to explore the effect of planarity on the selectivity of MI-COFs. The MI-TpTapa constructed from Tp and the lowest planarity of monomer Tapa gave the highest selectivity for OTA, and was further used as the adsorbent for dispersed-solid phase extraction (DSPE) of OTA in alcohol samples. Coupling MI-TpTapa based DSPE with high-performance liquid chromatography allowed the matrix-effect free determination of OTA in alcohol samples with the limit of detection of 0.023 µg kg-1 and the recoveries of 91.4-97.6%. The relative standard deviation (RSD, n = 6) of intra and inter day was <3.2%. This work provides a new way to construct MI-COFs for selective extraction of hazardous targets.


Asunto(s)
Contaminación de Alimentos , Impresión Molecular , Ocratoxinas , Extracción en Fase Sólida , Ocratoxinas/análisis , Ocratoxinas/aislamiento & purificación , Ocratoxinas/química , Extracción en Fase Sólida/métodos , Extracción en Fase Sólida/instrumentación , Cromatografía Líquida de Alta Presión , Contaminación de Alimentos/análisis , Adsorción , Alcoholes/química , Alcoholes/aislamiento & purificación , Estructuras Metalorgánicas/química
9.
Artículo en Inglés | MEDLINE | ID: mdl-38591772

RESUMEN

Two yeast strains, designated as 19-39-3 and 19-40-2, obtained from the fruiting bodies of Trametes versicolor and Marasmius siccus collected in Yunwu Mountain Forest Park, PR China, have been identified as representing a novel asexual ascomycetous yeast species. From the results of phylogenetic analyses of the sequences of the D1/D2 domains of the large subunit (LSU) rRNA, small subunit (SSU) rRNA and translation elongation factor 1-α (TEF1) genes, it was determined that these strains represent a member of the genus Wickerhamomyces, with Wickerhamomyces alni and Candida ulmi as the closest relatives. The novel species exhibited 6.6 and 6.7% differences in the D1/D2 domains compared with W. alni and C. ulmi, respectively. Additionally, distinct biochemical and physiological differences were observed between the novel species and its related counterparts. No sexual reproduction was observed in these strains, leading to the proposal of the name Wickerhamomyces corioli f.a., sp. nov. for this newly discovered species.


Asunto(s)
Agaricales , Saccharomycetales , Filogenia , ADN Espaciador Ribosómico/genética , Agaricales/genética , Trametes/genética , Análisis de Secuencia de ADN , Composición de Base , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Ácidos Grasos/química , Saccharomycetales/genética , ADN de Hongos/genética , Técnicas de Tipificación Micológica
10.
Phytomedicine ; 128: 155261, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38493716

RESUMEN

BACKGROUND: Recurrence and metastasis are the main causes of disease deterioration in colorectal cancer (CRC) patients, yet efficient therapeutic strategies are lacking. Natural compounds for efficient antitumour therapeutics are becoming increasingly prominent. Kaempferol, one of the main components of flavonoids in plants, displays a variety of pharmacological activities. Our preliminary experiments suggested that kaempferol could inhibit CRC metastasis and is significantly associated with the ß-catenin signalling pathway. Moreover, we also defined the regulatory roles of JMJD2C in ß-catenin signalling in our previous work. PURPOSE: This study aims to reveal the mechanism by which kaempferol inhibits CRC progression and regulates the JMJD2C/ß-catenin signalling pathway. METHODS: The migratory capabilities of CRC cells after kaempferol intervention were measured by scratch wound healing and transwell assays. Circ_0000345 knockdown CRC stable cell lines were generated by lentivirus infection. The possible mechanism of kaempferol on circ_0000345 was verified by molecular-protein docking and verification program cellular thermal shift assay (CETSA). A dual luciferase reporter gene assay was carried out for the targeting relationship among circ_0000345, miR-205-5p and JMJD2C. Fluorescence in situ hybridization (FISH) was performed to determine the expression of circ_0000345 in tumour tissues. A pulmonary metastatic model of CRC in vitro was built to assess the antimetastatic effect and mechanism of kaempferol in vivo. RESULTS: In vitro, kaempferol inhibits the ability to migrate of CRC cells by reducing the activation of the JMJD2C/ß-catenin signalling pathway. MiR-205-5p is a key bridge for kaempferol to inhibit the expression of JMJD2C. The function of miR-205-5p is impeded by circ_0000345, which shows higher expression levels in human metastatic CRC tissues than nonmetastatic CRC tissues, and its formation is regulated by the RNA-binding proteins HNRNPK and HNRNPL. Mechanistically, kaempferol physically interacts with HNRNPK and HNRNPL to suppress JMJD2C by downregulating the expression of circ_0000345. In vivo, kaempferol suppresses CRC lung metastasis. Kaempferol inhibits the activation of JMJD2C/ß-catenin signalling through reducing the expression of circ_0000345 in the CRC lung metastasis model. CONCLUSION: Circ_0000345 enhances activation of the JMJD2C/ß-catenin signalling pathway through miR-205-5p to promote CRC metastasis. Kaempferol inhibits CRC metastasis through the circ_0000345-mediated JMJD2C/ß-catenin signalling pathway, and this effect is influenced as a direct consequence of the binding of kaempferol with HNRNPK and HNRNPL. This provides promising therapeutic and/or adjuvant agents for advanced CRC and sheds light on the multifaceted role of phytomedicine in cancer.


Asunto(s)
Neoplasias Colorrectales , Histona Demetilasas con Dominio de Jumonji , Quempferoles , beta Catenina , Quempferoles/farmacología , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Histona Demetilasas con Dominio de Jumonji/metabolismo , beta Catenina/metabolismo , Animales , Movimiento Celular/efectos de los fármacos , Línea Celular Tumoral , ARN Circular/metabolismo , ARN Circular/genética , Transducción de Señal/efectos de los fármacos , Ratones Desnudos , Ratones Endogámicos BALB C , Masculino , MicroARNs/metabolismo , MicroARNs/genética , Ratones , Simulación del Acoplamiento Molecular
11.
Anal Chem ; 96(8): 3561-3568, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38372135

RESUMEN

Covalent organic frameworks (COFs) are attractive adsorbents for sample pretreatment due to their unique structure and properties. However, the selectivity of COFs for the extraction of hazardous compounds is still limited due to the lack of specific interactions between COFs and targets. Herein, we report a pore size adjustment strategy for room-temperature synthesis of molecularly imprinted COF (MICOF) for selective extraction of zearalenone (ZEN) in complex food samples. The three-dimensional building block tetra(4-aminophenyl) methane was used as a functional monomer, while dialdehyde monomers with different numbers of benzene ring were used to adjust the pore size of MICOF to match with the size of ZEN molecules. The prepared MICOF gave the largest adsorption capacity of 177.2 mg g-1 and the highest imprinting factor of 10.1 for ZEN so far. MICOF was used as the adsorbent for dispersed solid-phase extraction in combination with high-performance liquid chromatography for the determination of trace ZEN in cereals. The high selectivity of the developed method allows simple aqueous standard calibration for the matrix effect-free determination of ZEN in food samples. The limit of detection and the recoveries of the developed method were 0.21 µg kg-1 and 93.7-101.4%, respectively. The precision for the determination of ZEN was less than 3.8% (RSD, n = 6). The developed method is promising for the selective determination of ZEN in complex matrices.


Asunto(s)
Estructuras Metalorgánicas , Nanosferas , Zearalenona , Estructuras Metalorgánicas/química , Zearalenona/análisis , Grano Comestible/química , Temperatura , Cromatografía Líquida de Alta Presión/métodos , Extracción en Fase Sólida/métodos , Adsorción
12.
J Mater Chem B ; 11(46): 11094-11102, 2023 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-37987617

RESUMEN

Covalent organic frameworks (COFs) have promising applications in enhanced phototherapy. However, COFs that can sustainably play a role in phototherapy without continuous irradiation are extremely scarce. Herein, we report the fabrication of porphyrin-anthracene multifunctional COFs (Por-DPA) for sustainable photosterilization and bacterial-infected wound healing. A porphyrin photosensitizer, as one of the monomers, was used to provide photothermal and photodynamic activities under irradiation. An anthracene derivative, a good chemical source of singlet oxygen (1O2), was selected as another monomer to capture 1O2 and release it continuously via cycloreversion in the dark. The prepared Por-DPA COF prevents the self-aggregation quenching of the photosensitizer and thermal damage caused by continuous exposure to external light sources. Besides, Por-DPA exhibits good photothermal conversion performance and efficient 1O2 production capacity through dual pathways of photosensitization and cycloreversion. The developed sustainable photosterilization platform not only has good bactericidal effects on Escherichia coli and Staphylococcus aureus, but also promotes wound healing without obvious side effects, and is expected to be a novel efficient bactericide.


Asunto(s)
Estructuras Metalorgánicas , Porfirinas , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Estructuras Metalorgánicas/farmacología , Estructuras Metalorgánicas/química , Porfirinas/farmacología , Porfirinas/química , Fototerapia , Oxígeno Singlete/metabolismo
13.
ACS Appl Mater Interfaces ; 15(39): 46449-46459, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37738541

RESUMEN

Oxide-based memristors composed of Ag/porous SiOx/Si stacks are fabricated using different etching time durations between 0 and 90 s, and the memristive properties are analyzed in the relative humidity (RH) range of 30-60%. The combination of humidity and porous structure provides binding sites to control silver filament formation with a confined nanoscale channel. The memristive properties of devices show high on/off ratios up to 108 and a dispersion coefficient of 0.1% of the high resistance state (CHRS) when the RH increases to 60%. Humidity-mediated silver ion migration in the porous SiOx memristors is investigated, and the mechanism leading to the synergistic effects between the porous structure and environmental humidity is elucidated. The artificial neural network constructed theoretically shows that the recognition rate increases from 60.9 to 85.29% in the RH range of 30-60%. The results and theoretical understanding provide insights into the design and optimization of oxide-based memristors in neuromorphic computing applications.

14.
ACS Appl Mater Interfaces ; 15(33): 39669-39676, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37579002

RESUMEN

Thermally activated delayed fluorescence (TADF) emitters based on multiple resonance (MR) effects are promising for high-definition organic light-emitting diodes (OLEDs) with narrowband emission and high efficiency. However, they still face the challenges of aggregation-caused quenching (ACQ) and spectral broadening. Solution-processable MR-TADF emitters with an external quantum efficiency (EQE) of >20% and a full width at half-maximum (fwhm) of <30 nm have rarely been reported. To construct ACQ-resistant emitters without sacrificing color purity, the aggregation-induced MR-TADF material 6TBN with a rigid B,N-containing polycyclic aromatic hydrocarbon core and four carbazole substituents as well as 12 tert-butyl groups on the periphery is designed. The multidimensional shielded effect largely limits the ACQ, intermolecular interactions, and spectral broadening. Consequently, solution-processed OLEDs based on 6TBN exhibit a maximum EQE of 23.0% and high color purity with a fwhm of 25 nm. Furthermore, the nondoped device achieves a high efficiency (12.3%) and merely a slight widening of the fwhm to 27 nm. This work provides a feasible strategy to achieve MR-TADF materials with resistance to concentration quenching and high color purity.

15.
Research (Wash D C) ; 6: 0144, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37228637

RESUMEN

Insects that can perform flapping-wing flight, climb on a wall, and switch smoothly between the 2 locomotion regimes provide us with excellent biomimetic models. However, very few biomimetic robots can perform complex locomotion tasks that combine the 2 abilities of climbing and flying. Here, we describe an aerial-wall amphibious robot that is self-contained for flying and climbing, and that can seamlessly move between the air and wall. It adopts a flapping/rotor hybrid power layout, which realizes not only efficient and controllable flight in the air but also attachment to, and climbing on, the vertical wall through a synergistic combination of the aerodynamic negative pressure adsorption of the rotor power and a climbing mechanism with bionic adhesion performance. On the basis of the attachment mechanism of insect foot pads, the prepared biomimetic adhesive materials of the robot can be applied to various types of wall surfaces to achieve stable climbing. The longitudinal axis layout design of the rotor dynamics and control strategy realize a unique cross-domain movement during the flying-climbing transition, which has important implications in understanding the takeoff and landing of insects. Moreover, it enables the robot to cross the air-wall boundary in 0.4 s (landing), and cross the wall-air boundary in 0.7 s (taking off). The aerial-wall amphibious robot expands the working space of traditional flying and climbing robots, which can pave the way for future robots that can perform autonomous visual monitoring, human search and rescue, and tracking tasks in complex air-wall environments.

16.
Nano Lett ; 23(10): 4216-4225, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-37155369

RESUMEN

Adjuvant whole-breast radiotherapy is essential for breast cancer patients who adopted breast-conserving surgery (BCS) to reduce the risk of local recurrences, which however suffer from large-area and highly destructive ionizing radiation-induced adverse events. To tackle this issue, an afterglow/photothermal bifunctional polymeric nanoparticle (APPN) is developed that utilizes nonionizing light for precise afterglow imaging-guided post-BCS adjuvant second near-infrared (NIR-II) photothermal therapy. APPN consists of a tumor cell targeting afterglow agent, which is doped with a NIR dye as an afterglow initiator and a NIR-II light-absorbing semiconducting polymer as a photothermal transducer. Such a design realizes precise afterglow imaging-guided NIR-II photothermal ablation of minimal residual breast tumor foci after BCS, thus achieving complete inhibition of local recurrences. Moreover, APPN enables early diagnosis and treatment of local recurrence after BCS. This study thus provides a nonionizing modality for precision post-BCS adjuvant therapy and early recurrence theranostic.


Asunto(s)
Nanopartículas , Medicina de Precisión , Humanos , Fototerapia , Polímeros , Recurrencia , Línea Celular Tumoral
17.
Adv Mater ; 35(30): e2300854, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37119091

RESUMEN

Immunotherapy has offered new opportunities to treat head and neck squamous cell carcinoma (HNSCC); however, its clinical applications are hindered by modest therapeutic outcomes and the "always-on" pharmacological activity of immunomodulatory agents. Strategies for precise spatiotemporal activation of antitumor immunity can tackle these issues but remain challenging. Herein, a semiconducting polymeric nanoagonist (SPNM) with in situ sono-activatable immunotherapeutic effects for precision sono-immunotherapy of HNSCC is reported. SPNM is self-assembled from a sonodynamic semiconducting polymer core conjugated with a stimulator of interferon genes (STING) agonist (MSA-2) via a singlet oxygen cleavable linker. Under sono-irradiation, SPNM produces singlet oxygen not only to eradicate tumor cells to trigger immunogenic cell death but also to unleash caged STING agonists via the cleavage of diphenoxyethene bonds for in situ activation of the STING pathway in the tumor region. Such sono-driven STING activation mediated by SPNM promotes effector T cell infiltration and potentiates systemic antitumor immunity, eventually leading to tumor growth inhibition and long-term immunological memory. This study thus presents a promising strategy for the precise spatiotemporal activation of cancer immunotherapy.


Asunto(s)
Neoplasias de Cabeza y Cuello , Neoplasias , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Oxígeno Singlete , Linfocitos T , Inmunoterapia , Neoplasias de Cabeza y Cuello/tratamiento farmacológico
18.
Adv Mater ; 35(24): e2210920, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36938865

RESUMEN

Tumor vascular disrupting therapy has offered promising opportunities to treat cancer in clinical practice, whereas the overall therapeutic efficacy is notably limited due to the off-target effects and repeated dose toxicity of vascular disrupting agents (VDAs). To tackle this problem, a VDA-free biomimetic semiconducting polymer nanoparticle (SPNP ) is herein reported for precise tumor vascular disruption through two-stage light manipulation. SPNP consists of a semiconducting polymer nanoparticle as the photothermal agent camouflaged with platelet membranes that specifically target disrupted vasculature. Upon the first photoirradiation, SPNP administered in vivo generates mild hyperthermia to trigger tumor vascular hemorrhage, which activates the coagulation cascade and recruits more SPNP to injured blood vessels. Such enhanced tumor vascular targeting of photothermal agents enables intense hyperthermia to destroy the tumor vasculature during the second photoirradiation, leading to complete tumor eradication and efficient metastasis inhibition. Intriguingly, the mechanism study reveals that this vascular disruption strategy alleviates splenomegaly and reverses the immunosuppressive tumor microenvironment by reducing myeloid-derived suppressor cells. Therefore, this study not only illustrates a light-driven self-recruitment strategy to enhance tumor vascular disruption via a single dose of biomimetic therapeutics but also deciphers the immunotherapeutic role of vascular disruption therapy that is conducive to clinical studies.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Polímeros/uso terapéutico , Biomimética , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Nanopartículas/uso terapéutico , Plaquetas , Línea Celular Tumoral , Microambiente Tumoral
19.
Angew Chem Int Ed Engl ; 62(23): e202303563, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36994849

RESUMEN

Electrocatalytic water splitting powered by renewable energy is a sustainable approach for hydrogen production. However, conventional water electrolysis may suffer from gas mixing, and the different kinetics between hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) will limit the direct use of unstable renewable energies, leading to increased cost of H2 production. Herein, a novel phenazine-based compound is synthesized to develop the solid-state redox mediator associated water splititng process, and thus decoupling the H2 and O2 production in acid solution without the use of membrane. Excitingly, this organic redox mediator exhibits high specific capacity (290 mAh g-1 at 0.5 A g-1 ), excellent rate performance (186 mAh g-1 at 30 A g-1 ) and long cycle life (3000 cycles) due to its π-conjugated aromatic structure and the fast kinetics of H+ storage/release process. Furthermore, a membrane-free decoupled water electrolysis architecture driven by solar energy is achieved, demonstrating high-purity H2 production at different times.

20.
World J Surg Oncol ; 21(1): 114, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36978172

RESUMEN

BACKGROUND: In recent years, researchers have proposed a number of adjuvant methods for extended curettage of giant cell tumors of the bone. However, various schemes have significant differences in efficacy and safety. Therefore, this article will describe an empirical expanded curettage protocol, 'triple clear', in detail to show the effect of the efficient surgical protocol. METHOD: Patients with Campanacci grades II and III primary GCTB who were treated with either SR (n = 39) or TC (n = 41) were included. Various perioperative clinical indicators, including the therapy modality, operation time, Campanacci grade, and filling material were recorded and compared. The pain level was determined by the visual analog scale. Limb function was determined by the Musculoskeletal Tumour Society (MSTS) score. Follow-up time, recurrence rates, reoperation rates, and complication rates were also recorded and compared. RESULT: The operation time was 135.7 ± 38.4 min in the TC group and 174.2 ± 43.0 min in the SR group (P < 0.05). The recurrence rates were 7.3% in the TC group and 8.3% in the SR group (P = 0.37). The MSTS scores at three months after surgery were 19.8 ± 1.5 in the TC group and 18.8 ± 1.3 in the SR group. The MSTS scores at two years were 26.2 ± 1.2 in the TC group and 24.3 ± 1.4 in the SR group (P < 0.05). CONCLUSION: TC is recommended for patients with Campanacci grade II-III GCTB and for those with a pathological fracture or slight joint invasion. Bone grafts may be more suitable than bone cement in the long term.


Asunto(s)
Neoplasias Óseas , Fracturas Espontáneas , Tumor Óseo de Células Gigantes , Humanos , Neoplasias Óseas/patología , Fracturas Espontáneas/etiología , Fracturas Espontáneas/cirugía , Tumor Óseo de Células Gigantes/patología , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/complicaciones , Células Gigantes/patología , Estudios Retrospectivos , Legrado , Resultado del Tratamiento
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