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1.
Talanta ; 274: 126037, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38604046

RESUMEN

Antimony (Sb) is a toxic and potentially carcinogenic element in the environment. The toxicity of Sb(III) is ten times that of Sb(V). Therefore, on-site monitoring technique for dissolved Sb species is crucial for the study of Sb environmental processes. In this study, an automated, portable, and cost-effective system was developed for field simultaneous analysis of Sb(III) and Sb(III + V) in natural waters. The system comprised a portable atomic fluorescence spectrometer equipped with a built-in electrochemical H2 generator to reduce the consumption of acid/borohydride solution and make the atomizer more stable for on-site analysis. Flow injection technique was also used to achieve on-line pretreatment of water samples, including filtration, acidification, pre-reduction, and hydride generation procedures. Under the optimal conditions, the limits of detection (3σ, n = 11) of the developed method were 0.015 µg/L and the linear ranges were 0.05-5.0 µg/L for both Sb(III) and Sb(III + V). The relative standard deviations (n = 11) of the spiked samples of Sb(V) were 3.2% (0.05 µg/L), 3.3% (0.2 µg/L), and 1.7% (0.5 µg/L), respectively. The spiked recoveries of lake water, treated wastewater, and seawater ranged from 97.0% to 108.5%. The novel system of flow injection coupled with hydride generation atomic fluorescence spectrometer (FI-HG-AFS) was applied to carry out an 18-h fixed-point monitoring at a secondary settling tank of a wastewater treatment facility in Xiamen University, and a 6-h real-time underway analysis in the surface seawater of Dongshan Bay, China, proving that the system was capable of long-term monitoring in the field.

2.
Chem Soc Rev ; 53(4): 2211-2247, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38240305

RESUMEN

Recently, high-entropy (HE) materials have attracted increasing interest in various fields due to their unique characteristics. Rare earth (RE) elements have a similar atomic radius and gradually occupied 4f orbitals, endowing them with abundant optical, electric, and magnetic properties. Furthermore, HE-RE materials exhibit good structural and thermal stability and various functional properties, emerging as an important class of HE materials, which are on the verge of rapid development. However, a comprehensive review focusing on the introduction and in-depth understanding of HE-RE materials has not been reported to date. Thus, this review endeavors to provide a comprehensive summary of the development and research status of HE-RE materials, including alloys and ceramics, ranging from their structure, synthesis, and properties to applications. In addition, some distinctive issues of HR-RE materials related to the special electronic structure of RE are also discussed. Finally, we put forward the current challenges and future development directions of HE-RE materials. We hope that this review will provide inspiration for new design ideas and valuable references in this emerging field in the future.

3.
Small ; 19(33): e2301392, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37086136

RESUMEN

As an important lanthanide (Ln)-based functional materials, the Ln chalcogenides possess unique properties and various applications. However, the controllable synthesis of Ln chalcogenide nanocrystals still faces great challenges because of the rather poor affinity between Ln and chalcogenide ions (S, Se, Te) as well as strong preference of combination with existed oxygen. Herein, a facile but general heterogeneous nucleation synthetic strategy is established toward a series of colloidal ternary Cu Ln sulfides nanocrystals using the Ln dithiocarbamates and CuI as precursors. To extend this synthetic protocol, similar strategy is used to prepare six kinds of high quality CuLnS2 nanocrystals, while the bulk ones are only obtained by the traditional solid-state reaction at rigorous condition. Importantly, high-entropy nanocrystals CuLnS2 and CuEux Ln2-x S3 which contain six Ln elements (Nd, Sm, Gd, Tb, Dy) are readily obtained by the co-decomposed process attributed to their similar diffusion speed. As a proof-of-concept application, CuEu2 S3 nanocrystals showed efficient photocatalytic hydrogen production properties.

4.
Pharmaceuticals (Basel) ; 16(1)2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36678568

RESUMEN

Gold nanoparticles (AuNPs) are cutting-edge platforms for combined diagnostic and therapeutic approaches due to their exquisite physicochemical and optical properties. Using the AuNPs physically produced by femtosecond pulsed laser ablation of bulk Au in deionized water, with a capping agent-free surface, the conjugation of functional ligands onto the AuNPs can be tunable between 0% and 100% coverage. By taking advantage of this property, AuNPs functionalized by two different types of active targeting ligands with predetermined ratios were fabricated. The quantitatively controllable conjugation to construct a mixed monolayer of multiple biological molecules at a certain ratio onto the surface of AuNPs was achieved and a chelator-free 64Cu-labeling method was developed. We report here the manufacture, radiosynthesis and bioevaluation of three different types of dual-ligand AuNPs functionalized with two distinct ligands selected from glucose, arginine-glycine-aspartate (RGD) peptide, and methotrexate (MTX) for tumor theragnosis. The preclinical evaluation demonstrated that tumor uptakes and retention of two components AuNP conjugates were higher than that of single-component AuNP conjugates. Notably, the glucose/MT- modified dual-ligand AuNP conjugates showed significant improvement in tumor uptake and retention. The novel nanoconjugates prepared in this study make it possible to integrate several modalities with a single AuNP for multimodality imaging and therapy, combining the power of chemo-, thermal- and radiation therapies together.

5.
Chem Sci ; 13(42): 12367-12373, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36382279

RESUMEN

CoF2, with a relatively high theoretical capacity (553 mA h g-1), has been attracting increasing attention in the energy storage field. However, a facile and controllable synthesis of monodispersed CoF2 and CoF2-based nano-heterostructures have been rarely reported. In this direction, an eco-friendly and precisely controlled colloidal synthesis strategy to grow uniformly sized CoF2 nanorods and LiF-tipped CoF2-nanorod heterostructures based on a seeded-growth method is established. The unveiled selective growth of LiF nanoparticles onto the two end tips of the CoF2 nanorods is associated with the higher energy of tips, which favors the nucleation of LiF nanocrystals. Notably, it was found that LiF could protect CoF2 from corrosion even after 9 months of aging. In addition, the as-obtained heterostructures were employed in supercapacitors and lithium sulfur batteries as cathode materials. The heterostructures consistently exhibited higher specific capacities than the corresponding two single components in both types of energy storage devices, making it a potential electrode material for energy storage applications.

6.
Cytokine ; 99: 287-296, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28826648

RESUMEN

Toll like receptor (TLR) ligands are important adjuvant candidates, causing antigen presenting cells to release inflammatory mediators, leading to the recruitment and activation of other leukocytes. The aim of this study was to define the response of human blood derived dendritic cells and macrophages to three TLR ligands acting singly or in combination, Poly I:C (TLR3), GLA (TLR4) and R848 (TLR7/8). Combinations of TLR agonists have been shown to have a synergistic effect on individual cytokines, here we look at the global inflammatory response measuring both cytokines and chemokines. Using a custom Luminex assay we saw dose responses in several mediators including CCL3 (MIP1α), IL-1α, IL-1ß, IL-12, CXCL10 (IP-10) and IL-6, all of which were significantly increased by the combination of R848 and GLA, even when low dose GLA was added. The synergistic effect was inhibited by specific MAP kinase inhibitors blocking the kinases p38 and JNK but not MEK1. Combining TLR adjuvants also had a synergistic effect on cytokine responses in human mucosal tissue explants. From this we conclude that the combination of R848 and GLA potentiates the inflammatory profile of antigen presenting cells. Since the pattern of inflammatory mediators released can alter the quality and quantity of the adaptive immune response to vaccination, this study informs vaccine adjuvant design.


Asunto(s)
Adyuvantes Farmacéuticos/farmacología , Citocinas/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas , Receptores Toll-Like/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Biomarcadores/metabolismo , Quimiocinas/metabolismo , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Humanos , Imidazoles/farmacología , Mediadores de Inflamación/metabolismo , Ligandos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , Receptores Toll-Like/agonistas
7.
Immunology ; 151(4): 451-463, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28375554

RESUMEN

Age affects the immune response to vaccination, with individuals at the extremes of age responding poorly. The initial inflammatory response to antigenic materials shapes the subsequent adaptive response and so understanding is required about the effect of age on the profile of acute inflammatory mediators. In this study we measured the local and systemic inflammatory response after influenza vaccination or infection in neonatal, young adult and aged mice. Mice were immunized intramuscularly with inactivated influenza vaccine with and without the adjuvant MF59 and then challenged with H1N1 influenza. Age was the major factor affecting the inflammatory profile after vaccination: neonatal mice had more interleukin-1α (IL-1α), C-reactive protein (CRP) and granulocyte-macrophage colony-stimulating factor (GMCSF), young adults more tumour necrosis factor-α (TNF), and elderly mice more interleukin-1 receptor antagonist (IL-1RA), IL-2RA and interferon-γ-induced protein 10 (IP10). Notably the addition of MF59 induced IL-5, granulocyte colony-stimulating factor (G-CSF), Keratinocyte Chemotractant (KC) and monocyte chemoattractant protein 1 (MCP1) in all ages of animals and levels of these cytokines correlated with antibody responses. Age also had an impact on the efficacy of vaccination: neonatal and young adult mice were protected against challenge, but aged mice were not. There were striking differences in the localization of the cytokine response depending on the route of exposure: vaccination led to a high serum response whereas intranasal infection led to a low serum response but a high lung response. In conclusion, we demonstrate that age affects the inflammatory response to both influenza vaccination and infection. These age-induced differences need to be considered when developing vaccination strategies for different age groups.


Asunto(s)
Envejecimiento/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Pulmón/inmunología , Infecciones por Orthomyxoviridae/inmunología , Animales , Animales Recién Nacidos , Anticuerpos Antivirales/sangre , Citocinas/metabolismo , Humanos , Mediadores de Inflamación/metabolismo , Pulmón/virología , Ratones , Polisorbatos/administración & dosificación , Escualeno/administración & dosificación , Vacunación
8.
J Virol ; 89(17): 8974-81, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26085154

RESUMEN

UNLABELLED: The small hydrophobic (SH) gene of respiratory syncytial virus (RSV), a major cause of infant hospitalization, encodes a viroporin of unknown function. SH gene knockout virus (RSV ΔSH) is partially attenuated in vivo, but not in vitro, suggesting that the SH protein may have an immunomodulatory role. RSV ΔSH has been tested as a live attenuated vaccine in humans and cattle, and here we demonstrate that it protected against viral rechallenge in mice. We compared the immune response to infection with RSV wild type and RSV ΔSH in vivo using BALB/c mice and in vitro using epithelial cells, neutrophils, and macrophages. Strikingly, the interleukin-1ß (IL-1ß) response to RSV ΔSH infection was greater than to wild-type RSV, in spite of a decreased viral load, and when IL-1ß was blocked in vivo, the viral load returned to wild-type levels. A significantly greater IL-1ß response to RSV ΔSH was also detected in vitro, with higher-magnitude responses in neutrophils and macrophages than in epithelial cells. Depleting macrophages (with clodronate liposome) and neutrophils (with anti-Ly6G/1A8) demonstrated the contribution of these cells to the IL-1ß response in vivo, the first demonstration of neutrophilic IL-1ß production in response to viral lung infection. In this study, we describe an increased IL-1ß response to RSV ΔSH, which may explain the attenuation in vivo and supports targeting the SH gene in live attenuated vaccines. IMPORTANCE: There is a pressing need for a vaccine for respiratory syncytial virus (RSV). A number of live attenuated RSV vaccine strains have been developed in which the small hydrophobic (SH) gene has been deleted, even though the function of the SH protein is unknown. The structure of the SH protein has recently been solved, showing it is a pore-forming protein (viroporin). Here, we demonstrate that the IL-1ß response to RSV ΔSH is greater in spite of a lower viral load, which contributes to the attenuation in vivo. This potentially suggests a novel method by which viruses can evade the host response. As all Pneumovirinae and some Paramyxovirinae carry similar SH genes, this new understanding may also enable the development of live attenuated vaccines for both RSV and other members of the Paramyxoviridae.


Asunto(s)
Interleucina-1beta/inmunología , Infecciones por Virus Sincitial Respiratorio/inmunología , Virus Sincitiales Respiratorios/genética , Virus Sincitiales Respiratorios/inmunología , Proteínas Oncogénicas de Retroviridae/genética , Animales , Línea Celular , Células Epiteliales/inmunología , Células Epiteliales/virología , Femenino , Eliminación de Gen , Técnicas de Inactivación de Genes , Humanos , Interleucina-1beta/biosíntesis , Macrófagos/inmunología , Macrófagos/virología , Ratones , Ratones Endogámicos BALB C , Neutrófilos/inmunología , Neutrófilos/virología , Infecciones por Virus Sincitial Respiratorio/virología , Vacunas contra Virus Sincitial Respiratorio/inmunología , Virus Sincitiales Respiratorios/crecimiento & desarrollo , Vacunación , Vacunas Atenuadas/inmunología , Carga Viral/inmunología
9.
Eur J Med Res ; 19: 62, 2014 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-25384343

RESUMEN

BACKGROUND: Knowledge of the oncogenic signaling pathways of T-cell acute lymphoblastic leukemia (T-ALL) remains limited. Constitutive aberrant activation of the nuclear factor kappa B (NF-κB) signaling pathway has been detected in various lymphoid malignancies and plays a key role in the development of these carcinomas. The zinc finger-containing protein, A20, is a central regulator of multiple NF-κB-activating signaling cascades. A20 is frequently inactivated by deletions and/or mutations in several B-and T-cell lymphoma subtypes. However, few A20 mutations and polymorphisms have been reported in T-ALL. Thus, it is of interest to analyze the expression characteristics of A20 and its regulating factors, including upstream regulators and the CBM complex, which includes CARMA1, BCL10, and MALT1. METHODS: The expression levels of CARMA1, BCL10, MALT1, A20, and NF-κB were detected in peripheral blood mononuclear cells (PBMCs) from 21 patients with newly diagnosed T-ALL using real-time PCR, and correlations between the aberrant expression of these genes in T-ALL was analyzed. Sixteen healthy individuals, including 10 males and 6 females, served as controls. RESULTS: Significantly lower A20 expression was found in T-ALL patients (median: 4.853) compared with healthy individuals (median: 8.748; P = 0.017), and significantly increased expression levels of CARMA1 (median: 2.916; P = 0.034), BCL10 (median: 0.285; P = 0.033), and MALT1 (median: 1.201; P = 0.010) were found in T-ALL compared with the healthy individuals (median: 1.379, 0.169, and 0.677, respectively). In contrast, overexpression of NF-κB (median: 0.714) was found in T-ALL compared with healthy individuals (median: 0.335; P = 0.001). A negative correlation between the MALT1 and A20 expression levels and a positive correlation between CARMA1 and BCL10 were found in T-ALL and healthy individuals. However, no negative correlation was found between A20 and NF-κB and the MALT1 and NF-κB expression level in the T-ALL group. CONCLUSIONS: We characterized the expression of the CARMA-BCL10-MALT1-A20-NF-κB pathway genes in T-ALL. Overexpression of CARMA-BCL10-MALT in T-ALL may contribute to the constitutive cleavage and inactivation of A20, which enhances NF-κB signaling and may be related to T-ALL pathogenesis.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Proteínas Adaptadoras de Señalización CARD/biosíntesis , Caspasas/biosíntesis , Proteínas de Unión al ADN/biosíntesis , Guanilato Ciclasa/biosíntesis , Péptidos y Proteínas de Señalización Intracelular/biosíntesis , FN-kappa B/biosíntesis , Proteínas de Neoplasias/biosíntesis , Proteínas Nucleares/biosíntesis , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Adolescente , Adulto , Anciano , Proteína 10 de la LLC-Linfoma de Células B , Proteínas Adaptadoras de Señalización CARD/genética , Caspasas/genética , Niño , Preescolar , Proteínas de Unión al ADN/genética , Femenino , Regulación Leucémica de la Expresión Génica , Guanilato Ciclasa/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Masculino , Persona de Mediana Edad , Proteína 1 de la Translocación del Linfoma del Tejido Linfático Asociado a Mucosas , Mutación , FN-kappa B/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Transducción de Señal , Linfocitos T/patología , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa
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