RESUMO
Immunotherapy has emerged as a highly effective treatment for various tumors. However, the variable response rates associated with current immunotherapies often restrict their beneficial impact on a subset of patients. Therefore, more effective treatment approaches that can broaden the scope of therapeutic benefits to a larger patient population are urgently needed. Studies have shown that some parasites and their products, for example, Plasmodium, Toxoplasma, Trypanosoma, and Echinococcus, can effectively transform "cold" tumors into "hot" battlefields and reshape the tumor microenvironment, thereby stimulating innate and adaptive antitumor immune responses. These parasitic infections not only achieve the functional reversal of innate immune cells, such as neutrophils, macrophages, myeloid-derived suppressor cells, regulatory T cells, and dendritic cells, in tumors but also successfully activate CD4+/CD8+ T cells and even B cells to produce antibodies, ultimately resulting in an antitumor-specific immune response and antibody-dependent cellular cytotoxicity. Animal studies have confirmed these findings. This review discusses the abovementioned content and the challenges faced in the future clinical application of antitumor treatment strategies based on parasitic infections. With the potential of these parasites and their byproducts to function as anticancer agents, we anticipate that further investigations in this field could yield significant advancements in cancer treatment.
Assuntos
Imunoterapia , Neoplasias , Humanos , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/terapia , Animais , Parasitos/imunologia , Microambiente Tumoral/imunologiaRESUMO
Ephedra herb (EH), an important medicine prescribed in herbal formulas by Traditional Chinese Medicine practitioners, has been widely used in the treatment of viral pneumonia in China. However, the molecular basis of EH in viral pneumonia remains unclear. In this study, a ternary correlation multi-symptom network strategy was established based on in vivo chemical profile identification and metabolomics to explore the molecular basis of EH against viral pneumonia. Results showed that 143 compounds of EH and 70 prototype components were identified in vivo. EH could reduce alveolar-capillary barrier disruption in rats with viral pneumonia and significantly downregulate the expression of inflammatory factors and bronchoalveolar lavage fluid. Plasma metabolomics revealed that EH may be involved in the regulation of arachidonic acid, tryptophan, tyrosine, nicotinate, and nicotinamide metabolism. The multi-symptom network showed that 12 compounds have an integral function in the treatment of viral pneumonia by intervening in many pathways related to viruses, immunity and inflammation, and lung injury. Further verification demonstrated that sinapic acid and frambinone can regulate the expression of related genes. It has been shown to be a promising representative of the pharmacological constituents of ephedra.
Assuntos
Medicamentos de Ervas Chinesas , Ephedra , Metabolômica , Ratos Sprague-Dawley , Animais , Ratos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Ephedra/química , Masculino , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/metabolismo , Pneumonia Viral/virologiaRESUMO
Recently, stimulus-responsive organic materials with room-temperature phosphorescence (RTP) properties have attracted significant attention owing to their potential applications in chemical sensing, anticounterfeiting, and displays. However, molecular design currently lacks systematicity and effectiveness. Herein, we report a capture-release strategy for the construction of reversible RTP via B/N Lewis pairs. Specifically, the RTP of the Lewis acid of 7-bromo-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene (BrBA) can be deactivated through capturing by the Lewis base, N,N-diphenyl-4-(pyridin-4-yl)aniline (TPAPy), and reactivated by dissociation of B-N bonds to release BrBA. Reversible RTP is attributed to the exceptional self-assembly capability of BrBA, whereas the tunable RTP colors are derived from distinct Förster resonance energy transfer (FRET) processes. The potential applications of RTP materials in information storage and anti-counterfeiting were also experimentally validated. The capture-release approach proposed in this study offers an effective strategy for designing stimulus-responsive materials.
RESUMO
Organic luminescent radicals, unlike traditional closed-shell fluorescent emitters, exhibit distinct luminescence mechanisms, offering promising potential for optoelectronic devices. To date, stable luminescent radicals have predominantly been confined to polychlorinated triphenylmethyl radicals, underscoring the need for new platforms to expand their emission spectra. In this study, we report the synthesis of stable 9-aryl-substituted xanthene radicals and their heavy chalcogen analogues (1a-c and 2a-c), which exhibited excellent chemical stability and emission ranging from green to near-infrared (527~714 nm). Notably, the selenium-substituted radical (1c) demonstrates a significantly enhanced photoluminescence quantum yield of 41% when doped into its precursor solid. Additionally, the introduction of methoxyphenyl groups has largely enhanced the stability of the radical, showcasing an excellent photostability with the longest half-life of around 1792 h. The high internal quantum efficiency of up to 81% was further validated in organic light-emitting diode. This study introduces a novel class of stable carbon-centered radicals with high tunability and functionality for photoelectric applications.
RESUMO
Recently, the remarkable advances in thermally activated delayed fluorescence (TADF) materials have attracted much attention due to their 100% exciton utilization efficiency in organic light-emitting diodes (OLEDs). Although the commercialization of TADF materials is at an early stage, they exhibit enormous potential for next-generation OLEDs due to the comparable electroluminescence performance to metal of their phosphorescent complex counterparts, but without the presence of precious metal elements. This review summarizes the different types of TADF small molecules with various photophysical properties and the state-of-the-art molecular design strategies. Furthermore, the device engineering is discussed, and emerging optoelectronic applications, such as organic light-emitting electrochemical cells, organic lasing, and organic scintillators, are introduced. It is anticipated that this review can clarify the design of efficient TADF emitters and point out the direction of future development.
RESUMO
Moiré superlattices are twisted bilayer materials in which the tunable interlayer quantum confinement offers access to new physics and novel device functionalities. Previously, moiré superlattices were built exclusively using materials with weak van der Waals interactions, and synthesizing moiré superlattices with strong interlayer chemical bonding was considered to be impractical. Here, using lead sulfide (PbS) as an example, we report a strategy for synthesizing moiré superlattices coupled by strong chemical bonding. We use water-soluble ligands as a removable template to obtain free-standing ultrathin PbS nanosheets and assemble them into direct-contact bilayers with various twist angles. Atomic-resolution imaging shows the moiré periodic structural reconstruction at the superlattice interface due to the strong metavalent coupling. Electron energy loss spectroscopy and theoretical calculations collectively reveal the twist-angle-dependent electronic structure, especially the emergent separation of flat bands at small twist angles. The localized states of flat bands are similar to well-arranged quantum dots, promising an application in devices. This study opens a new door to the exploration of deep energy modulations within moiré superlattices alternative to van der Waals twistronics.
RESUMO
BACKGROUND: This study aimed to investigate the work status of clinicians in China and their management strategy alteration for patients with hepatocellular carcinoma (HCC) during the COVID-19 pandemic. METHODS: A nationwide online questionnaire survey was conducted in 42 class-A tertiary hospitals across China. Experienced clinicians of HCC-related specialties responded with their work status and management suggestions for HCC patients during the pandemic. RESULTS: 716 doctors responded effectively with a response rate of 60.1%, and 664 were included in the final analysis. Overall, 51.4% (341/664) of clinicians reported more than a 60% reduction of the regular workload and surgeons declared the highest proportion of workload reduction. 92.5% (614/664) of the respondents have been using online medical consultation to substitute for the "face-to-face" visits. Adaptive adjustment for the treatment strategy for HCC was made, including the recommendations of noninvasive and minimally invasive treatments such as transcatheter arterial chemoembolization for early and intermediate stage. Targeted therapy has been the mainstay for advanced stage and also as a bridge therapy for resectable HCC. DISCUSSION: During the COVID-19 pandemic, online medical consultation is recommended to avoid social contact. Targeted therapy as a bridge therapy is recommended for resectable HCC considering the possibility of delayed surgery.
Assuntos
COVID-19 , Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/terapia , Pandemias , SARS-CoV-2 , Inquéritos e QuestionáriosRESUMO
Scanning transmission electron microscopy (STEM) allows for imaging, diffraction, and spectroscopy of materials on length scales ranging from microns to atoms. By using a high-speed, direct electron detector, it is now possible to record a full two-dimensional (2D) image of the diffracted electron beam at each probe position, typically a 2D grid of probe positions. These 4D-STEM datasets are rich in information, including signatures of the local structure, orientation, deformation, electromagnetic fields, and other sample-dependent properties. However, extracting this information requires complex analysis pipelines that include data wrangling, calibration, analysis, and visualization, all while maintaining robustness against imaging distortions and artifacts. In this paper, we present py4DSTEM, an analysis toolkit for measuring material properties from 4D-STEM datasets, written in the Python language and released with an open-source license. We describe the algorithmic steps for dataset calibration and various 4D-STEM property measurements in detail and present results from several experimental datasets. We also implement a simple and universal file format appropriate for electron microscopy data in py4DSTEM, which uses the open-source HDF5 standard. We hope this tool will benefit the research community and help improve the standards for data and computational methods in electron microscopy, and we invite the community to contribute to this ongoing project.
RESUMO
In this study, the antioxidant property changes in fermented Ziziphi Spinosae Semen(FZSS) with Poria cocos were analyzed by DPPH, ABTS and FRAP methods. Then the content determination of active ingredients and ~1H nuclear magnetic resonance(~1H-NMR) spectroscopy were also used to investigate the mechanism of FZSS with P. cocos in enhancing the antioxidant activity. The results showed that the content of active ingredients such as total phenols, total saponins and total polysaccharides were significantly increased during the fermentation time. The results of ~1H-NMR metabonomics showed that the contents of amino acids such as leucine, lysine, valine and alanine, nitrogen compounds such as creatine, creatinine, and betaine, and secondary metabolites, for instance, jujuboside A and spinosin were higher after fermentation, and above components showed positive correlation with antioxidant capacity in Pearson correlation analysis. Therefore, it was inferred that the enhancement of antioxidant activity of FZSS may be the result of the joint action of various chemical components. This study preliminarily clarified the mechanism of FZSS in enhancing the antioxidant activity, and provided new research ideas for the product development and utilization of FZSS.
Assuntos
Medicamentos de Ervas Chinesas , Poria , Wolfiporia , Ziziphus , Antioxidantes , Cromatografia Líquida de Alta Pressão , SêmenRESUMO
Large-scale, controlled fabrication of ordered phases is challenging at the nanoscale, yet highly demanded as their well-ordered structure and chemistry is the key for advanced functionality. Here, we demonstrate a general nanomolding process of ordered phases based on atomic diffusion. Resulting nanowires are single crystals and maintain their composition and structure throughout their length, which we explain by a self-ordering process originating from their narrow Gibbs free energy. The versatility, control, and precision of this thermomechanical nanomolding method of ordered phases provides new insights into single crystal growth and suggest itself as a technology to enable wide spread usage for nanoscale and quantum devices.
RESUMO
The development of organic room-temperature phosphorescence (RTP) is accompanied by opportunities and challenges. RTP from crystal polymorphism has aroused much attention, due to the significant different photophysical characteristics and intermolecular packings found in the same molecule with different crystal phases. Herein, we report three organic molecules BP-o-BO, BP-m-BO, and BP-p-BO, in which two crystal polymorphisms of BP-p-BO are successfully cultivated with different emission properties. BP-p-BO-A exhibits bright cyan photoluminescence (PL) with a quantum yield of 11.3% and a distinct RTP with a lifetime of 17.1 ms, which is much higher than the deep blue PL of BP-p-BO-B (6.9%) and the corresponding RTP lifetime of 3.3 ms. Crystal structure analyses indicate that the different emission properties can be ascribed to the different intermolecular packing, further demonstrating the essential role of molecular packing in the designing of RTP materials.
RESUMO
The energetic chemical reaction between Zn(NO3 )2 and Li is used to create a solid-state interface between Li metal and Li6.4 La3 Zr1.4 Ta0.6 O12 (LLZTO) electrolyte. This interlayer, composed of Zn, ZnLix alloy, Li3 N, Li2 O, and other species, possesses strong affinities with both Li metal and LLZTO and affords highly efficient conductive pathways for Li+ transport through the interface. The unique structure and properties of the interlayer lead to Li metal anodes with longer cycle life, higher efficiency, and better safety compared to the current best Li metal electrodes operating in liquid electrolytes while retaining comparable capacity, rate, and overpotential. All-solid-state Li||Li cells can operate at very demanding current-capacity conditions of 4â mA cm-2 -8â mAh cm-2 . Thousands of hours of continuous cycling are achieved at Coulombic efficiency >99.5 % without dendrite formation or side reactions with the electrolyte.
RESUMO
Seeking earth-abundant electrocatalysts with high efficiency and durability has become the frontier of energy conversion research. Mixed-transition-metal (MTM)-based electrocatalysts, owing to the desirable electrical conductivity, synergistic effect of bimetal atoms, and structural stability, have recently emerged as new-generation hydrogen evolution reaction (HER) electrocatalysts. However, the correlation between anion species and their intrinsic electrocatalytic properties in MTM-based electrocatalysts is still not well understood. Here we present a novel approach to tuning the anion-dependent electrocatalytic characteristics in MTM-based catalyst for HER, using holey Ni/Co-based phosphides/selenides/oxides (Ni-Co-A, A = P, Se, O) as the model materials. The electrochemical results, combined with the electrical conductivity measurement and DFT calculation, reveal that P substitution could modulate the electron configuration, lower the hydrogen adsorption energy, and facilitate the desorption of hydrogen on the active sites in Ni-Co-A holey nanostructures, resulting in superior HER catalytic activity. Accordingly we fabricate the NCP holey nanosheet electrocatalyst for HER with an ultralow onset overpotential of nearly zero, an overpotential of 58 mV, and long-term durability, along with an applied potential of 1.56 V to boost overall water splitting at 10 mA cm-2, among the best electrocatalysts reported for non-noble-metal catalysts to date. This work not only presents a deeper understanding of the intrinsic HER electrocatalytic properties for MTM-based electrocatalyst with various anion species but also offers new insights to better design efficient and durable water-splitting electrocatalysts.
RESUMO
Two-dimensional (2D) energy materials have shown the promising electrochemical characteristics for lithium ion storage. However, the decreased active surfaces and the sluggish charge/mass transport for beyond-lithium ion storage that has potential for large-scale energy storage systems, such as sodium or potassium ion storage, caused by the irreversible restacking of 2D materials during electrode processing remain a major challenge. Here we develop a general interlayer engineering strategy to address the above-mentioned challenges by using 2D ultrathin vanadyl phosphate (VOPO4) nanosheets as a model material for challenging sodium ion storage. Via controlled intercalation of organic molecules, such as triethylene glycol and tetrahydrofuran, the sodium ion transport in VOPO4 nanosheets has been significantly improved. In addition to advanced characterization including X-ray diffraction, high-resolution transmission electron microscopy, and X-ray absorption fine structure to characterize the interlayer and the chemical bonding/configuration between the organic intercalants and the VOPO4 host layers, density functional theory calculations are also performed to understand the diffusion behavior of sodium ions in the pure and TEG intercalated VOPO4 nanosheets. Because of the expanded interlayer spacing in combination with the decreased energy barriers for sodium ion diffusion, intercalated VOPO4 nanosheets show much improved sodium ion transport kinetics and greatly enhanced rate capability and cycling stability for sodium ion storage. Our results afford deeper understanding of the interlayer-engineering strategy to improve the sodium ion storage performance of the VOPO4 nanosheets. Our results may also shed light on possible multivalent-ion based energy storage such as Mg2+ and Al3+.
RESUMO
We report the first example of an AIEgen (DPP-BO) with fluorescence-phosphorescence dual emission under mechanical stimulation. By carefully analyzing the crystal structure of DPP-BO, the efficient intermolecular and intramolecular interactions should account for its unique mechanoluminescence (ML) properties, especially the abnormal phosphorescence, as further confirmed by controlled experiments and theoretical calculations for the presence of ISC transitions. These results provide important information for understanding the complex ML process, possibly opening up a new way to study the inherent mechanism of ML by broadening the application of AIEgens.
RESUMO
Silole derivatives, the first reported and famous AIEgens, are a series of Si-containing conjugated rings with the σ*-π* conjugation, and this unique electronic structure imparts them high electron affinity and fast electron mobility, but not ideal blue luminogens due to their relatively long conjugation length. By replacing the Si atom with the C one, six new AIEgens without the σ*-π* conjugation effect are successfully synthesized based on a tetraphenylcyclopentadiene core. In addition to the sky-blue emission (λEL = 492 nm) with Lmax , ηC,max , and ηP,max up to 24 096 cd m-2 , 6.80 cd A-1 , and 4.07 lm W-1 , respectively, the careful control of the conjugation degree by changing the linkage mode, results in the blue one (λEL = 440 nm) with relatively good performance (Lmax : 8721 cd m-2 and ηC,max : 3.40 cd A-1 ), indicating that the replacement of the Si atom by C one is an alternative design strategy to yield blue even deep-blue AIEgens with good device performance. Meanwhile, their reversible mechanochromic properties are realized with apparent fluorescence changes between deep-blue and green emissive colors, offering them additional promising applications in optoelectronic devices.
RESUMO
Indium (In) doping in topological crystalline insulator SnTe induces superconductivity, making In-doped SnTe a candidate for a topological superconductor. SnTe nanostructures offer well-defined nanoscale morphology and high surface-to-volume ratios to enhance surface effects. Here, we study In-doped SnTe nanoplates, In(x)Sn(1-x)Te, with x ranging from 0 to 0.1 and show they superconduct. More importantly, we show that In doping reduces the bulk mobility of In(x)Sn(1-x)Te such that the surface states are revealed in magnetotransport despite the high bulk carrier density. This is manifested by two-dimensional linear magnetoresistance in high magnetic fields, which is independent of temperature up to 10 K. Aging experiments show that the linear magnetoresistance is sensitive to ambient conditions, further confirming its surface origin. We also show that the weak antilocalization observed in In(x)Sn(1-x)Te nanoplates is a bulk effect. Thus, we show that nanostructures and reducing the bulk mobility are effective strategies to reveal the surface states and test for topological superconductors.
Assuntos
Nanoestruturas/química , Telúrio/química , Estanho/química , Propriedades de SuperfícieRESUMO
Over recent decades, aggregation-induced emission (AIE) molecules have attracted increasing attention. Restriction of intramolecular rotation (RIR) has been widely accepted as the cause of the emission when AIE molecules aggregate into clusters. The intramolecular rotation of AIE molecules can be monitored by molecular vibration spectra such as nuclear magnetic resonance (NMR), infrared, and Raman, especially surface-enhanced Raman scattering (SERS) which has high sensitivity down to a single molecule. We employed SERS and NMR to study the AIE emission mechanism and compared experimental results with simulation data to monitor the RIR. Interestingly, we found that intramolecular rotation was also restricted for individual AIE molecules loaded onto SERS substrate surfaces due to the laid-down configuration.
RESUMO
Aggregation-induced emission (AIE) is commonly observed for propeller-like luminogens with aromatic rotors and stators. Herein, we report that a coumarin derivative containing a seven-membered aliphatic ring (CD-7) but no rotors showed typical AIE characteristics, whereas its analogue with a five-membered aliphatic ring (CD-5) exhibited an opposite aggregation-caused quenching (ACQ) effect. Experimental and theoretical results revealed that a large aliphatic ring in CD-7 weakens structural rigidity and promotes out-of-plane twisting of the molecular backbone to drastically accelerate nonradiative excited-state decay, thus resulting in poor emission in solution. The restriction of twisting motion in aggregates blocks the nonradiative decay channels and enables CD-7 to fluoresce strongly. The results also show that AIE is a general phenomenon and not peculiar to propeller-like molecules. The AIE and ACQ effects can be switched readily by the modulation of molecular rigidity.