Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
1.
Small ; 20(17): e2307615, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38111975

RESUMO

Transition metal phosphides (TMPs) have been regarded as the prospective anodes for lithium-ion batteries (LIBs). However, their poor intrinsic conductivity and inevitable large volume variation result in sluggish redox kinetics and the collapse of electrode structure during cycling, which substantially hinders their practical use. Herein, an effective composite electrodes design strategy of "assembly and phosphorization" is proposed to construct synergistic N-doped carbon-encapsulated NiCoP@N-C-based composites, employing a metal-organic frameworks (MOFs) as sacrificial hosts. Serving as the anodes for LIBs, one representative P-NCP-NC-600 electrode exhibits high reversible capacity (858.5 mAh g-1, 120 cycles at 0.1 A g-1) and superior long-cycle stability (608.7 mAh g-1, 500 cycles at 1 A g-1). The impressive performances are credited to the synergistic effect between its unique composite structure, electronic properties and ideal composition, which achieve plentiful lithium storage sites and reinforce the structural architecture. By accompanying experimental investigations with theoretical calculations, a deep understanding in the lithium storage mechanism is achieved. Furthermore, it is revealed that a more ideal synergistic effect between NiCoP components and N-doped carbon frameworks is fundamentally responsible for the realization of superb lithium storage properties. This strategy proposes certain instructive significance toward designable high-performance TMP-based anodes for high-energy density LIBs.

2.
Support Care Cancer ; 32(6): 394, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814489

RESUMO

OBJECTIVES: Radiation dermatitis is the most common reaction to radiotherapy, almost all breast cancer patients receive radiotherapy on an outpatient basis. Currently, there are no studies on the experience of radiation dermatitis and the ability to self-manage it. Therefore, we aimed to use qualitative approaches to gain a deeper understanding of the actual experiences and self-management ability in order to provide a reference for further improving the effectiveness of self-management and to optimize symptom management strategies. METHODS: A descriptive qualitative study was conducted using purposive sampling to select 17 breast cancer patients undergoing radiotherapy. Semi-structured interviews were conducted from September to November 2023. The Colaizzi seven-step analysis method was used to classify the data into summarized themes. RESULTS: Four themes were identified from the interview responses: (1) multiple self-reported skin symptoms in breast cancer patients with radiation dermatitis; (2) the multidimensional impact on patient's quality of life, especially pruritus, ulceration; (3) the ability to self-manage radiation dermatitis: strong mental toughness, positive response, and self-doubt; (4) challenges faced: concerns about radiotherapy side effects and recurrence, targeted symptom management and continuity of care after the radiotherapy. CONCLUSIONS: Healthcare professionals should consider patients' self-reported symptoms when assessing radiation dermatitis. For pruritus and pain, we can enhance precision symptom management to improve patients' quality of life. By utilizing information technology tools, we can increase breast cancer patients' ability and confidence in managing radiation dermatitis effectively while enhancing accurate symptom management during radiotherapy.


Assuntos
Neoplasias da Mama , Pesquisa Qualitativa , Qualidade de Vida , Radiodermite , Autogestão , Humanos , Feminino , Neoplasias da Mama/radioterapia , Pessoa de Meia-Idade , Autogestão/métodos , Radiodermite/etiologia , Adulto , Idoso , China , Entrevistas como Assunto , Radioterapia/efeitos adversos , População do Leste Asiático
3.
J Clin Nurs ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075789

RESUMO

AIM: To investigate symptom clusters and sentinel symptoms in breast cancer survivors based on self-reported outcomes, explore the impact of sentinel symptoms on patients' quality of life and psychological distress, provide a basis for implementing accurate symptom management. DESIGN: A cross-sectional survey. METHODS: The study was conducted from September 2021 to December 2022. We recruited 281 patients who were re-examined in an outpatient department of a tertiary hospital in Hebei Province. The European Organization for the Research and Treatment of Cancer (EORTC) Quality-of-Life Questionnaire - Core30 (QLQ-C30), the EORTC Quality-of-Life Questionnaire Breast Cancer - 23 (QLQ-BR23), the Hospital Anxiety and Depression Scale (HADS) were used to conduct the survey. Symptom clusters were explored using principal component analysis, sentinel symptoms were explored using the Apriori algorithm. Correlation analysis was used to explore the relationship between sentinel symptoms and quality of life, correlation with psychological distress. This paper adhered to the STROBE guidelines. RESULTS: Breast cancer survivors have a wide range of self-reported symptoms in the form of four symptom clusters: a fatigue symptom cluster, a gastrointestinal symptom cluster, a sickness symptom cluster and a surgical trauma-related symptom cluster. Three sentinel symptoms were explored: pain, alopecia and limited function of the upper limbs. Except for sexual function, all of the sentinel symptoms were negatively correlated with patients' quality of life and positively correlated with psychological distress (p < .05). CONCLUSIONS: Breast cancer survivors have a variety of symptoms in the form of four symptom clusters. Pain, alopecia and limited function of the upper limbs are the sentinel symptoms, which affect patients' quality of life and psychological distress.

4.
Angew Chem Int Ed Engl ; : e202409436, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016543

RESUMO

The appearance of disordered lithium dendrites and fragile solid electrolyte interfaces (SEI) significantly hinder the serviceability of lithium metal batteries. Herein, guided by theoretical predictions, a multi-component covalent triazine framework with partially electronegative channels (4C-TA0.5TF0.5-CTF) is incorporated as a protective layer to modulate the interface stability of the lithium metal batteries. Notably, the 4C-TA0.5TF0.5-CTF with optimized electronic structure at the molecular level by fine-tuning the local acceptor-donor functionalities not only enhances the intermolecular interaction thereby providing larger dipole moment and improved crystallinity and mechanical stress, but also facilitates the beneficial effect of lithiophilic sites (C-F bonds, triazine cores, C=N linkages and aromatic rings) to further regulate the migration of Li+ and achieve a uniform lithium deposition behavior as determined by various in-depth in/ex situ characterizations. Due to the synergistic effect of multi-component organic functionalities, the 4C-TA0.5TF0.5-CTF modified full cells perform significantly better than the common two/three-component 2C-TA-CTF and 3C-TF-CTF electrodes, delivering an excellent capacity of 116.3 mAh g-1 (capacity retention ratio: 86.8%) after 1000 cycles at 5 C and improved rate capability. This work lays a platform for the prospective molecular design of improved organic framework relative artificial SEI for highly stable lithium metal batteries.

5.
Angew Chem Int Ed Engl ; 63(15): e202320259, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332561

RESUMO

Fatal issues in lithium metal anodes (LMA), such as detrimental lithium dendrites growth and fragile solid-electrolyte interphase (SEI) during the Li plating/stripping process, often hinder the practical application of Li metal batteries (LMBs). Herein, cobalt-coordinated sp-carbon-conjugated organic polymer (Co-spc-COP) is constructed as the protective layer for regulating the interface stability of LMA. The unique synergistic beneficial effect of organic functional groups (C≡C linkage, C=N units and aromatic rings) and Co sites not only regulate the Li+ coordination environment and rearrange Li+ concentration to facilitate its transport by optimizing the electronic density, enhancing the compatibility with electrolyte interface and supplying "external magnetic driving strategy", but also strengthens the interfacial stiffness with high Young's modulus to better withstand the mechanical stress. These beneficial effects and relative underlying working mode and mechanism of uniform Li plating and rapid Li+ migration on the Co-spc-COP are also revealed by various in situ/ex situ experimental technologies and theory calculation. The Co-spc-COP-based cell delivers an extraordinary lifespan of 6600 h and ultrahigh capacity retention of 78.3 % (111.9 mAh g-1) after 1000 cycles at 1 C. This demonstrated synergistic strategy in Co-coordinated organic polymer may gain new insights to regulate the uniform and non-dendritic deposition/dissolution behaviors for highly stable LMBs.

6.
Financ Res Lett ; 47: 102820, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35370484

RESUMO

This paper finds the degree of investor's investment diversification is found to be positively correlated with confirmed cases in the city where they live. This relationship is a result of stricter quarantine policy adopted by cities hit with more severe Covid-19 outbreak, which has led to increased time for investors to trade stocks and seek advisory. In addition, the employment of investors in these cities is often negatively affected. Therefore, they tend to hold a relatively pessimistic view on expectations of future income, and thus be more cautious and risk-averse in terms of investment decisions.

7.
Macromol Rapid Commun ; 41(24): e2000098, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32430924

RESUMO

It is highly desirable to develop reversible and easy-release adhesives with high bonding strength for a broad range of substrates, while the adhesion of low-surface-energy materials (e.g., polytetrafluoretyhylene, PTFE) is challenging. Herein, a substrate-independent ionogel adhesive is developed by blending an ionic liquid with the copolymer bearing charged segments. By regulating the viscoelastic properties of the ionogel, the adhesive and cohesive strength of the ionogel can be well balanced to maximize the bonding strength for different substrates. The as-developed ionogel exhibits high bonding strength (>0.3 MPa) for PTFE, plastics, metal, wood, and glass, because the variety of functional groups in the ionogel can form various supramolecular interactions with different substrates. The ionogel also exhibits reversible, easy-release, and reusable properties for multiple times of bonding and on-demand debonding without leaving obvious residues on the substrates. The ionogel has high potential for practical applications as temporal adhesives with high bonding strength.


Assuntos
Adesivos , Polímeros , Teste de Materiais
8.
Water Sci Technol ; 76(5-6): 1565-1573, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28953482

RESUMO

Phosphorus flame retardant tricresyl phosphate (TCP) adsorption on graphene nanomaterials from aqueous solutions was explored using batch and column modes. Comparative studies were performed regarding the kinetics and equilibrium of TCP adsorption on graphene oxide (GO) and graphene (G) in batch mode. The adsorption kinetics exhibited a rapid TCP uptake, and experimental data were well described by the pseudo-second-order kinetic model. Adsorption isotherm data of TCP on the two adsorbents displayed an improved TCP removal performance with increasing temperature at pH 5, while experimental data were well described by the Langmuir isotherm model with a maximum adsorption capacity of 87.7 mg·g-1 for G, and 30.7 mg·g-1 for GO) at 303 K. The thermodynamic parameters show that the adsorption reaction is a spontaneous and endothermic process. In addition, dynamic adsorption of TCP in a fixed G column confirmed a faster approach to breakthrough at high flow rate, high influent TCP concentration, and low filling height of adsorbent. Breakthrough data were successfully described by the Thomas and Yoon-Nelson models.


Assuntos
Grafite/química , Nanoestruturas , Tritolil Fosfatos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Óxidos , Temperatura , Termodinâmica , Água/química
9.
Water Sci Technol ; 73(5): 1098-103, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26942532

RESUMO

Oil-water separation has recently become a worldwide challenge due to the frequent occurrence of oil spill accidents and increasing industrial oily wastewater. In this work, the multifunctional mesh films with underwater oleophobicity and certain bacteriostatic effects are prepared by layer-by-layer assembly of graphene oxide-silica coatings on stainless steel mesh. The mesh film exhibits excellent environmental stability under a series of harsh conditions. The new, facile and reusable separation system is proposed to achieve deep treatment of oily wastewater, and the oil collection rate can reach over 99%.


Assuntos
Grafite/química , Membranas Artificiais , Petróleo/análise , Dióxido de Silício/química , Águas Residuárias/química , Antibacterianos , Resíduos Industriais , Aço Inoxidável , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química
10.
Biochemistry ; 54(31): 4784-94, 2015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26204228

RESUMO

Amino acid repeat runs are common occurrences in eukaryotic proteins, with glutamine (Q) and asparagine (N) as particularly frequent repeats. Abnormal expansion of Q-repeat domains causes at least nine neurodegenerative disorders, most likely because expansion leads to protein misfolding, aggregation, and toxicity. The linkage between Q-repeats and disease has motivated several investigations into the mechanism of aggregation and the role of Q-repeat length in aggregation. Curiously, glutamine repeats are common in vertebrates, whereas N-repeats are virtually absent in vertebrates, but common in invertebrates. One hypothesis for the lack of N-repeats in vertebrates is biophysical; that is, there is strong selective pressure in higher organisms against aggregation-prone proteins. If true, then asparagine and glutamine repeats must differ substantially in their aggregation properties despite their chemical similarities. In this work, aggregation of peptides with asparagine repeats of variable length (12-24) were characterized and compared to that of similar peptides with glutamine repeats. As with glutamine, aggregation of N-repeat peptides was strongly length-dependent. Replacement of glutamine with asparagine caused a subtle shift in the conformation of the monomer, which strongly affected the rate of aggregation. Specifically, N-repeat peptides adopted ß-turn structural elements, leading to faster self-assembly into globular oligomers and much more rapid conversion into fibrillar aggregates, compared to Q-repeat peptides. These biophysical differences may account for the differing biological roles of N- versus Q-repeat domains.


Assuntos
Asparagina/química , Glutamina/química , Peptídeos/química , Sequências Repetitivas de Aminoácidos , Estrutura Secundária de Proteína
11.
J Pept Sci ; 20(11): 860-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25044797

RESUMO

Of all amino acid repeats in eukaryotes, polyglutamine (polyQ) is the most frequent, followed by polyasparagine (polyN). Glutamine repeats are expanded in proteins associated with several neurodegenerative disorders. The expanded polyQ domain is known to induce aggregation, and it is hypothesized that aggregation is directly causative of pathology. Despite the widespread presence of asparagine repeats in invertebrate eukaryotes, polyN is curiously quite rare in vertebrates. Several investigators have characterized the conformational and aggregation properties of polyQ-containing peptides and proteins, and to a lesser extent, peptides containing mixed glutamine and asparagine, but to our knowledge, there is no detailed characterization of polyN-containing peptides. Such a comparison could elucidate reasons for the paucity of asparagine repeats in humans. In this study, we synthesized a peptide containing a 24-asparagine repeat (N24). For aggregation studies, it is critical to start with monomeric unaggregated peptide. A protocol involving dissolution in mixed trifluoroacetic acid and hexafluoroisopropanol (TFA + HFIP) solvents is widely used for disaggregation of polyQ peptides. We used the same protocol for N24 but discovered that there was both oxidative damage and insufficient disaggregation. Oxidation of tryptophan, used as a flanking residue, was common. Moreover, we found evidence of Förster resonance energy transfer between Trp and its oxidation product N-formylkynurenine, even in chemical denaturants. This suggested that N24 was insufficiently disaggregated, a conclusion that was further supported by gel electrophoresis analysis. Oxidation was reduced, but not eliminated, by addition of methionine to the buffer. Formic acid proved to be a better disaggregator and caused no oxidative damage. The glutamine repeat peptide Q24 also underwent some oxidation after extended incubation in TFA + HFIP, but there was no evidence of Förster resonance energy transfer, and samples appeared monomeric by gel electrophoresis. This result indicates that polyN-containing peptides self-associate more strongly than polyQ-containing peptides. Circular dichroism spectra reveal a greater propensity for ß-turn formation in polyN than polyQ, providing an explanation for the increased stability of polyN aggregates relative to polyQ.


Assuntos
Peptídeos/química , Peptídeos/síntese química , Transferência Ressonante de Energia de Fluorescência , Humanos , Oxirredução , Propanóis , Conformação Proteica , Multimerização Proteica , Estabilidade Proteica , Estrutura Secundária de Proteína , Sequências Repetitivas de Aminoácidos , Ácido Trifluoracético
12.
ACS Nano ; 18(3): 2395-2408, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38194614

RESUMO

The development of high-energy-density Li-S batteries (LSBs) is still hindered by the disturbing polysulfide shuttle effect. Herein, with clever combination between "high entropy" and MXene, an HE-MXene doped graphene composite containing multiple element quasi-atoms as bifunctional mediator for separator modification (HE-MXene/G@PP) in LSBs is proposed. The HE-MXene/G@PP offers high electrical conductivity for fast lithium polysulfide (LiPS) redox conversion kinetics, abundant metal active sites for efficient chemisorption with LiPSs, and strong lipophilic characteristics for uniform Li+ deposition on lithium metal surface. As demonstrated by DFT theoretical calculations, in situ Raman, and DRT results successively, HE-MXene/G@PP efficiently captures LiPSs through synergistic modulation of the cocktail effect and accelerates the LiPSs redox reaction, and the lattice distortion effect effectively induces the homogeneous deposition of dendritic-free lithium. Therefore, this work achieves excellent long-term cycling performance with a decay rate of 0.026%/0.031% per cycle after 1200 cycles at 1 C/2 C. The Li||Li symmetric cell still maintains a stable overpotential after 6000 h under 40 mA cm-2/40 mAh cm-2. Furthermore, it delivers favorable cycling stability under 7.8 mg cm-2 and a low E/S ratio of 5.6 µL mg-1. This strategy provides a rational approach to resolve the sulfur cathode and lithium anode problems simultaneously.

13.
Adv Mater ; 36(11): e2308257, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38102857

RESUMO

The development of Li-free anodes to inhibit Li dendrite formation and provide high energy density Li batteries is highly applauded. However, the lithiophobic interphase and heterogeneous Li deposition hindered the practical application. In this work, a 20 nm ultra-sleek high entropy alloy (HEA, NiCdCuInZn) tights loaded with HEA nanoparticles are developed by a thermodynamically driven phase transition method on the carbon fiber (HEA/C). Multiple Li+ transport paths and abundant active sites are enabled by the cocktail effect of different constituent elements in HEA. These active sites with gradient absorption energies (-3.18 to -2.03 eV) facilitate selective binding, providing a low barrier for homogeneous Li nucleation. Simultaneously, multiple transport paths promote Li diffusion behavior with uniform Li deposition. Thus, the HEA/C achieves high reversibility of Li plating/stripping processes over 2000 cycles with a coulombic efficiency of 99.6% at 5 mA cm-2 /1 mAh cm-2 in asymmetric cells, as well as over 7200 h at 60 mA cm-2 /60 mAh cm-2 in symmetric cells. Moreover, the anode-free full cell with the HEA/C host has an average coulombic efficiency of 99.5% at 1 C after 160 cycles. This advanced HEA structure design shows a favorable potential application for anode-free Li metal batteries.

14.
Polymers (Basel) ; 15(7)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37050378

RESUMO

This work was investigated to prepare a reinforcing composite packaging film composited of soy protein/polyvinyl alcohol (PVA) and nano-TiO2. First, different film compositions were designed by the particle size of nano-TiO2, concentration of nano-TiO2, concentration of polyvinylpyrrolidone (PVP, a dispersing agent for nano-TiO2), and pH of film casting solution. Then, the film composition that yielded the optimal physical properties was identified using orthogonal array design single-factor experiments, considering its physical properties, including tensile strength, elongation, water absorption, water vapor transmission, oxygen permeation, thermal property, and film morphology. The results displayed that the optimal film composition was (1) soy protein/PVA film with 2.5 wt% nano-TiO2, (2) 30 nm nano-TiO2 particle size, (3) 1.5 wt% PVP, and (4) pH 6.0 of film-forming solution. It yielded tensile strength of 6.77 MPa, elongation at break rate of 58.91%, and water absorption of 44.89%. Last, the films were characterized by scanning electron microscope (SEM) and differential scanning calorimetry (DSC). SEM analysis showed that compared with the film without TiO2, the film containing TiO2 has a smoother surface, and DSC determined that adding nano-TiO2 can improve the thermostability of soy protein/PVA film. Therefore, the film prepared in this paper is expected to provide a new theoretical basis for use in the packaging industry.

15.
Head Neck ; 45(8): 1875-1884, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37309715

RESUMO

OBJECTIVE: To retrospectively analyze the comprehensive treatment strategy for internal carotid artery blowout syndrome (CBS) by nasopharyngeal carcinoma (NPC). METHODS: Of the 311 patients of NPC with carotid artery blowout syndrome admitted at our center from April 2018 to August 2022, 288 were enrolled. RESULTS: The patients were divided into two groups: treatment group (266 cases) and control group (22 cases). After comprehensive treatment, the survival rate of the treatment group was significantly higher than that of the control group, especially within 6 months to the 1 year. Preventive intervention for CBS I type may have considerable benefits. And in the long run, this treatment strategy did not significantly increase the incidence of stroke in the treatment group. CONCLUSION: The comprehensive treatment strategy for ICA-CBS of patients with NPC significantly reduced the mortality of asphyxia due to epistaxis, reduced the incidence of CBS during nasal endoscopy, and finally improved survival rate.


Assuntos
Doenças das Artérias Carótidas , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/complicações , Artéria Carótida Interna , Neoplasias Nasofaríngeas/terapia , Neoplasias Nasofaríngeas/complicações , Estudos Retrospectivos , Doenças das Artérias Carótidas/etiologia , Análise de Sobrevida
16.
Adv Mater ; 35(32): e2212116, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36961362

RESUMO

Lithium-sulfur (Li-S) batteries have become one of the most promising new-generation energy storage systems owing to their ultrahigh energy density (2600 Wh kg-1 ), cost-effectiveness, and environmental friendliness. Nevertheless, their practical applications are seriously impeded by the shuttle effect of soluble lithium polysulfides (LiPSs), and the uncontrolled dendrite growth of metallic Li, which result in rapid capacity fading and battery safety problems. A systematic and comprehensive review of the cooperative combination effect and tackling the fundamental problems in terms of cathode and anode synchronously is still lacking. Herein, for the first time, the strategies for inhibiting shuttle behavior and dendrite-free Li-S batteries simultaneously are summarized and classified into three parts, including "two-in-one" S-cathode and Li-anode host materials toward Li-S full cell, "two birds with one stone" modified functional separators, and tailoring electrolyte for stabilizing sulfur and lithium electrodes. This review also emphasizes the fundamental Li-S chemistry mechanism and catalyst principles for improving electrochemical performance; advanced characterization technologies to monitor real-time LiPS evolution are also discussed in detail. The problems, perspectives, and challenges with respect to inhibiting the shuttle effect and dendrite growth issues as well as the practical application of Li-S batteries are also proposed.

17.
Chem Biol Drug Des ; 102(6): 1534-1552, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37806949

RESUMO

Pouzolzia zeylanica (L.) Benn. is a Chinese herbal medicine widely used for its anti-inflammatory and pus-removal properties. To explore its potential anti-inflammatory mechanism, quercetin 3,7-dirhamnoside (QDR), the main flavonoid component of P. zeylanica (L.) Benn., was extracted and purified. The potential anti-inflammatory targets of QDR were predicted using network analysis. These potential targets were verified using molecular docking, molecular dynamics simulations, and in vitro experiments. Consequently, 342 potential anti-inflammatory QDR targets were identified. By analyzing the intersection between the protein-protein interaction and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, we identified several potential protein targets of QDR, including RAC-alpha serine/threonine-protein kinase (AKT1), Ras-related C3 botulinum toxin substrate 1 (RAC1), nitric oxide synthase 3 (NOS3), serine/threonine-protein kinase mTOR (mTOR), epidermal growth factor receptor (EGFR), growth factor receptor-bound protein 2 (GRB2), and endothelin-1 receptor (EDNRA). QDR has anti-inflammatory activity and regulates immune responses and apoptosis through chemokines, Phosphatidylinositol 3-kinase 3(PI3K)/AKT, cAMP, T-cell receptor, and Ras signaling pathways. Molecular docking analysis showed that QDR has good binding abilities with AKT1, mTOR, and NOS3. In addition, molecular dynamics simulations demonstrated that the protein-ligand complex systems formed between QDR and AKT1, mTOR, and NOS3 have high dynamic stability, and their protein-ligand complex systems possess strong binding ability. In RAW264.7 macrophages, QDR significantly inhibited lipopolysaccharides (LPS)-induced inducible nitric oxide synthase expression, nitric oxide (NO) release and the generation of proinflammatory cytokines IL-6, IL-1ß, and TNF-α. QDR downregulated the expression of p-AKT1(Ser473)/AKT1 and p-mTOR (Ser2448)/mTOR, and upregulated the expression of NOS3, Rictor, and Raptor. This indicates that the anti-inflammatory mechanisms of QDR involve regulation of AKT1 and mTOR to prevent apoptosis and of NOS3 which leads to the release of endothelial NO. Thus, our study elucidated the potential anti-inflammatory mechanism of QDR, the main flavonoid found in P. zeylanica (L.) Benn.


Assuntos
Medicamentos de Ervas Chinesas , Quercetina , Quercetina/farmacologia , Ligantes , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases , Flavonoides , Anti-Inflamatórios/farmacologia , Serina-Treonina Quinases TOR , Treonina , Serina , Medicamentos de Ervas Chinesas/farmacologia
18.
J Control Release ; 360: 858-871, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37473808

RESUMO

Tumor-associated macrophages (TAMs) are the major immune cells infiltrating the tumor microenvironment (TME) and typically exhibit an immunosuppressive M2-like phenotype, which facilitates tumor growth and promotes resistance to immunotherapy. Additionally, tumor cells tend to express high levels of CD47, a "don't eat me" signal, that obstructs macrophage phagocytosis. Consequently, re-educating TAMs in combination with CD47 blockage is promising to trigger intense macrophage immune responses against tumors. As a toll-like receptor 7/8 agonist, resiquimod (R848) possesses the capacity to re-educate TAMs from M2 type to M1 type. We found that intratumoral administration of R848 synergistically improved the antitumor immunotherapeutic effect of CV1 protein (a SIRPα variant with high antagonism to CD47). However, the poor bioavailability and potential toxicity of this combo strategy remain a challenge. Here, a TAMs-targeted liposome (named: R-LS/M/CV1) co-delivering R848 and CV1 protein was constructed via decorating mannose on the liposomal surface. R-LS/M/CV1 exhibited high abilities of targeting, re-education and pro-phagocytosis of tumor cells to M2 macrophages in vitro. Intratumoral administration of R-LS/M/CV1 remarkedly eliminated tumor burden in the MC38 tumor model via repolarization of TAMs to M1 type, pro-phagocytosis of TAMs against tumors, and recruitment of tumor-infiltrating T cells. More encouragingly, due to the double targeting to TAMs and tumor cells of mannose and CV1 protein, R-LS/M/CV1 effectively accumulated at the tumor site, thereby not only remarkedly inhibiting tumors, but also exerting no hematological and histopathological toxicity when administered systemically. Our integrated strategy based on re-educating TAMs and CD47 blockade provides a promising approach to trigger macrophage immune responses against tumors for immunotherapy.


Assuntos
Lipossomos , Neoplasias , Humanos , Lipossomos/metabolismo , Antígeno CD47 , Manose , Macrófagos/metabolismo , Fagocitose , Neoplasias/metabolismo , Imunoterapia , Microambiente Tumoral
19.
J Nanosci Nanotechnol ; 12(10): 8017-22, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23421172

RESUMO

Ag-loaded brookite titania (Ag/TiO2(B)) nanocomposites were prepared via photochemical reduction using silver acetate and pure TiO2(B) as precursor. The samples were characterized by X-ray diffraction spectrometry (XRD), ultraviolet-visible diffuse reflectance spectrometry (UV-vis DRS), transmission electron microscopy (TEM) and photoluminescence spectra (PL). Photocatalytic degradation of Rhodamine B (Rh B) and photocatalytic oxidation of benzyl alcohol served as a probe reaction to evaluate the photocatalytic activity of the as-prepared nanocomposites under visible light irradiation(lambda > 400 nm). The results indicate different Ag loading amount influence the activity of the samples, among which Ag/TiO2(B) with 2.5 wt% Ag content exhibited the best photodegradation activity of Rh B as well as the highest selectivity for photocatalytic oxidation of benzyl alcohol. The effect of Ag loading and reaction substrates on the performance of Ag/TiO2(B) is investigated in detail. Based on the characterization results and frontier electron density theory (FED) calculation, possible mechanism of the photocatalytic oxidation of benzyl alcohol by photo-generated holes is discussed.

20.
Polymers (Basel) ; 14(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35566863

RESUMO

This work was dedicated to improving the utilization rate of yellow peach peel (YPP), with the addition of sodium alginate (SA) and glycerol (G) to prepare a biodegradable antioxidant film. First, the formulation of the film was optimized via response surface methodology (RSM) combined with the multi-index comprehensive evaluation method, considering physical properties including tensile strength (TS), elongation at break (E%), water solution (WS) and light transmittance (T). The RSM results displayed the best process condition was 2.50% of YPP, 0.60% SA and 0.80% of G (based on water) and compared with pure YPP film and YPP-SA film, the optimized (YPP-SA-G) film presented excellent properties with TS of 21.52 MPa, E of 24.8%, T of 21.56% on 600 nm, and WS of 41.61%, the comprehensive evaluation score of the film was 0.700. Furthermore, the films were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). FTIR analysis showed the main interaction of hydrogen between YPP, SA and G make the film has excellent compatibility, and the SEM images displayed that the film was dense and compacted with a little roughness. In addition, the optimized film had excellent thermal stability, suggested by TGA and XRD showed that the film's crystal structure has been changed significantly when the SA and G were mixed in. The TPC and the ability of DPPH radical scavenging of the YPP-SA-G film was 17.68 mg·g-1 of GAE and 18.65%, then potential packaging applications were evaluated using soybean oil and the YPP-SA-G antioxidant film significantly decreased peroxide value (POV) to delay oil oxidation during storage. Therefore, the YPP-SA-G film is expected to provide a new theoretical basis for the use of food processing by-products and the packaging industry.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA