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1.
Nano Lett ; 24(21): 6353-6361, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38757814

RESUMEN

Polydopamine (PDA)-derived melanin-like materials exhibit significant photothermal conversion owing to their broad-spectrum light absorption. However, their low near-infrared (NIR) absorption and inadequate hydrophilicity compromise their utilization of solar energy. Herein, we developed metal-loaded poly(norepinephrine) nanoparticles (PNE NPs) by predoping metal ions (Fe3+, Mn3+, Co2+, Ca2+, Ga3+, and Mg2+) with norepinephrine, a neuron-derived biomimetic molecule, to address the limitations of PDA. The chelation between catechol and metal ions induces a ligand-to-metal charge transfer (LMCT) through the formation of donor-acceptor pairs, modulating the light absorption behavior and reducing the band gap. Under 1 sun illumination, the Fe-loaded PNE coated wood evaporator achieved a high seawater evaporation rate and efficiency of 1.75 kg m-2 h-1 and 92.4%, respectively, owing to the superior hydrophilicity and photothermal performance of PNE. Therefore, this study offers a comprehensive exploration of the role of metal ions in enhancing the photothermal properties of synthetic melanins.


Asunto(s)
Melaninas , Norepinefrina , Melaninas/química , Norepinefrina/química , Polimerizacion/efectos de la radiación , Polímeros/química , Neurotransmisores/química , Indoles/química , Oxidación-Reducción , Metales/química , Nanopartículas/química
2.
Opt Lett ; 49(9): 2449-2452, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691741

RESUMEN

Broadband frequency comb generation through cascaded quadratic nonlinearity remains experimentally untapped in free-space cavities with bulk χ(2) materials mainly due to the high threshold power and restricted ability of dispersion engineering. Thin-film lithium niobate (LN) is a good platform for nonlinear optics due to the tight mode confinement in a nano-dimensional waveguide, the ease of dispersion engineering, large quadratic nonlinearities, and flexible phase matching via periodic poling. Here we demonstrate broadband frequency comb generation through dispersion engineering in a thin-film LN microresonator. Bandwidths of 150 nm (80 nm) and 25 nm (12 nm) for center wavelengths at 1560 and 780 nm are achieved, respectively, in a cavity-enhanced second-harmonic generation (doubly resonant optical parametric oscillator). Our demonstration paves the way for pure quadratic soliton generation, which is a great complement to dissipative Kerr soliton frequency combs for extended interesting nonlinear applications.

3.
Langmuir ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38941474

RESUMEN

Metal oxides can activate peroxymonosulfate (PMS) for the catalytic degradation of organic dyes. However, achieving high catalytic efficiency, structural stability, ease of recovery, and recyclability remains challenging for both research and practical applications. To address these requirements, a bimetallic oxide, CuMnO2, was synthesized using a simple hydrothermal approach and was encapsulated to create hydrogel beads, CS-Ca@PEI/CuMnO2. Subsequently, CS-Ca@PEI/CuMnO2 was used to activate PMS and establish a solid-liquid heterogeneous oxidation system (CS-Ca@PEI/CuMnO2/PMS) for the degradation of Congo red (CR). The effects of various parameters such as different systems, catalyst dosages, initial pH values, PMS concentrations, temperatures, and anion types on the catalytic degradation properties of CS-Ca@PEI/CuMnO2 for CR were systematically evaluated. The results indicated that CS-Ca@PEI/CuMnO2 has exceptional degradation capacity, achieving 91.0% degradation of CR at pH 7. After three degradation cycles, the catalyst maintained an 86.9% degradation efficiency compared to its original performance, highlighting its robust structural stability. The presence of reactive radicals, specifically 1O2 and •O2-, were confirmed through quenching experiments, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance spectroscopy (EPR). Liquid chromatography-tandem mass spectrometry (LC-MS) revealed ten proposed intermediates in the catalytic degradation process. Due to its exceptional catalytic performance, structural durability, recyclability, and ease of retrieval, the catalyst shows great potential for effectively removing organic pollutants from industrial wastewater.

4.
Biomacromolecules ; 25(1): 522-531, 2024 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-38087829

RESUMEN

Ferroptosis has attracted significant attention as a new mechanism of cell death. Sorafenib (SRF) is widely considered a prototypical ferroptosis-inducing drug, particularly for liver cancer treatment. However, the low solubility and hydrophobic nature of SRF, along with the absence of synergistic therapeutic strategies, still limit its application in cancer treatment. Herein, we report a dual therapeutic method incorporating photothermal therapy and ferroptosis by using Fe-doped mesoporous polydopamine nanoparticles (Fe-mPDA@SRF-TPP) as a carrier for loading SRF and targeting triphenylphosphine (TPP). SRF molecules are efficiently encapsulated within the polydopamine nanospheres with a high loading ratio (80%) attributed to the porosity of Fe-mPDA, and the inherent biocompatibility and hydrophilicity of Fe-mPDA@SRF-TPP facilitate the transport of SRF to the target cancer cells. Under the external stimuli of acidic environment (pH 5.0), glutathione (GSH), and laser irradiation, Fe-mPDA@SRF-TPP shows sustained release of SRF and Fe ions with the ratio of 72 and 50% within 48 h. Fe-mPDA@SRF-TPP nanoparticles induce intracellular GSH depletion, inhibit glutathione peroxidase 4 (GPX4) activity, and generate hydroxyl radicals, all of which are essential components of the therapeutic ferroptosis process for killing MDA-MB-231 cancer cells. Additionally, the excellent near-infrared (NIR) light absorption of Fe-mPDA@SRF-TPP nanoparticles demonstrates their capability for photothermal therapy and further enhances the therapeutic efficiency. Therefore, this nanosystem provides a multifunctional therapeutic platform that overcomes the therapeutic limitations associated with standalone ferroptosis and enhances the therapeutic efficacy of SRF for breast cancer.


Asunto(s)
Ferroptosis , Neoplasias Hepáticas , Nanopartículas , Neoplasias , Humanos , Sorafenib/farmacología , Terapia Fototérmica , Hierro , Nanopartículas/química , Neoplasias/terapia , Concentración de Iones de Hidrógeno , Línea Celular Tumoral
5.
J Am Chem Soc ; 145(31): 17253-17264, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37498730

RESUMEN

The electrochemical CO2 reduction reaction (CO2RR) using renewable electricity is one of the most promising strategies for reaching the goal of carbon neutrality. Multicarbonous (C2+) products have broad applications, and ethanol is a valuable chemical and fuel. Many Cu-based catalysts have been reported to be efficient for the electrocatalytic CO2RR to C2+ products, but they generally offer limited selectivity and current density toward ethanol. Herein, we proposed a silica-mediated hydrogen-bonded organic framework (HOF)-templated approach to preparing ultrahigh-density Cu single-atom catalysts (SACs) on thin-walled N-doped carbon nanotubes (TWN). The content of Cu in the catalysts prepared by this method could be up to 13.35 wt %. It was found that the catalysts showed outstanding performance for the electrochemical CO2RR to ethanol, and the Faradaic efficiency (FE) of ethanol increased with the increase in Cu-N3 site density. The FE of ethanol over the catalysts with 13.35 wt % Cu could reach ∼81.9% with a partial current density of 35.6 mA cm-2 using an H-type cell, which is the best result for electrochemical CO2RR to ethanol to date. In addition, the catalyst could be stably used for more than 25 h. Experimental and density functional theory (DFT) studies revealed that the adjacent Cu-N3 active sites (one Cu atom coordinates with three N) were the active sites for the reaction, and their high density was crucial for the high FE of ethanol because the adjacent Cu-N3 sites with a short distance could promote the C-C coupling synergistically.

6.
Langmuir ; 39(29): 10145-10153, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37436959

RESUMEN

Molybdenum-based nanomaterials have shown promise for anticancer treatment due to their strong photothermal and redox-activated capabilities. Herein, we have fabricated cerium-doped MoOx (Ce-MoOv) with tunable Mo/Ce molar ratios by a one-pot method and investigated their effect on chemodynamic therapy (CDT) and photothermal therapy (PTT). It is found that Ce-MoOv can self-assemble into nanoclusters in acidic conditions and the increasing Ce amount will generate oxygen vacancy defects and induce the valence change of Mo6+/Mo5+ and Ce4+/Ce3+, which leads to strong near-infrared absorption with high photothermal conversion efficiency of 71.31 and 49.86% for 808 and 1064 nm. Other than photothermal conversion, the materials demonstrate pH-/glutathione (GSH)-activated photoacoustic (PA) imaging capability in vitro. In addition, Ce-MoOv acts as a CDT reagent capable of converting endogenous H2O2 to two types of reactive oxygen species (•OH, 1O2) while depleting GSH. Ce-MoOv demonstrates an excellent therapeutic effect against HCT116 cells and effectively reduces the intracellular GSH level and significantly increases the number of reactive radicals under 1064 nm laser irradiation as compared with the no-laser group in vitro. This work provides a new paradigm using lanthanide-doped polymetallic oxides for pH-/GSH-responsive photothermal/chemodynamic therapy with PA imaging ability.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Óxidos , Peróxido de Hidrógeno , Molibdeno , Microambiente Tumoral , Glutatión , Oxígeno , Concentración de Iones de Hidrógeno , Línea Celular Tumoral
7.
Molecules ; 28(18)2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37764495

RESUMEN

Our previous study found that the intravesical perfusion of metformin has excellent inhibitory effects against bladder cancer (BC). However, this administration route allows the drug to be diluted and excreted in urine. Therefore, increasing the adhesion of metformin to the bladder mucosal layer may prolong the retention time and increase the pharmacological activity. It is well known that chitosan (Cs) has a strong adhesion to the bladder mucosal layer. Thus, this study established a novel formulation of metformin to enhance its antitumor activity by extending its retention time. In this research, we prepared Cs freeze-dried powder and investigated the effect of metformin-loaded chitosan hydrogels (MLCH) in vitro and in vivo. The results showed that MLCH had a strong inhibitory effect against proliferation and colony formation in vitro. The reduction in BC weight and the expression of tumor biomarkers in orthotopic mice showed the robust antitumor activity of MLCH via intravesical administration in vivo. The non-toxic profile of MLCH was observed as well, using histological examinations. Mechanistically, MLCH showed stronger functional activation of the AMPKα/mTOR signaling pathway compared with metformin alone. These findings aim to make this novel formulation an efficient candidate for managing BC via intravesical administration.


Asunto(s)
Quitosano , Metformina , Neoplasias de la Vejiga Urinaria , Animales , Ratones , Vejiga Urinaria , Administración Intravesical , Metformina/farmacología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Modelos Animales de Enfermedad , Hidrogeles
8.
Zhongguo Zhong Yao Za Zhi ; 48(24): 6600-6612, 2023 Dec.
Artículo en Zh | MEDLINE | ID: mdl-38212020

RESUMEN

This study aimed to provide data support for resource utilization of the stems and leaves of Astragalus membranaceus var. mongholicus(SLAM) by analyzing and evaluating the chemical constituents. The crude protein, crude fiber, and soluble saccharide of SLAM were analyzed by Kjeldahl method, filtration method, and UV-Vis spectrophotometry, respectively. The nucleosides, amino acids, flavonoids, and saponins of SLAM were analyzed by ultraperformance liquid chromatography-triple quadrupole mass spectrometry(UPLC-TQ-MS). Combined with principal component analysis(PCA), the quality difference of resource components of SLAM was comprehensively evaluated. The results showed that the average content of crude protein, crude fiber, total polysaccharide, and redu-cing sugar in SLAM was 5.11%, 30.33%, 11.03 mg·g~(-1), and 31.90 mg·g~(-1), respectively. Six nucleosides, 15 amino acids, 22 flavonoids, and one saponin were detected, with an average content of 1.49 mg·g~(-1), 6.00 mg·g~(-1), 1.86 mg·g~(-1), and 35.67 µg·g~(-1), respectively. The content of various types of chemical components in SLAM differed greatly in different harvesting periods and growing years. The results of PCA showed that the quality of SLAM produced in Ningxia was superior. The results can provide references for the utilization of SLAM.


Asunto(s)
Astragalus propinquus , Saponinas , Astragalus propinquus/química , Cromatografía de Gases y Espectrometría de Masas , Flavonoides/análisis , Hojas de la Planta/química , Aminoácidos , Saponinas/análisis
9.
Opt Lett ; 47(1): 122-125, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34951897

RESUMEN

Kerr microcombs hold the promise of bringing frequency combs onto the chip and into a variety of applications requiring low size, weight, power, and cost. However, reliable Kerr microcomb generation is hindered by the thermal effect and multistability of dissipative Kerr solitons (DKSs). Past approaches toward Kerr microcomb reliability include either deterministic single-soliton generation or self-starting soliton behavior but not both. Here we describe a regime of DKSs that is both deterministic and self-starting, in which only a single soliton can stably exist. We term this new DKS regime "monostable DKSs" (MS-DKSs) as all other optical behaviors, such as continuous-wave-only and multiple solitons, are fundamentally forbidden by the design. We establish a graphical model to describe MS-DKSs and discuss the design principles of MS-DKSs. We numerically demonstrate the MS-DKS behavior in an example periodically poled lithium niobate microring resonator.

10.
Langmuir ; 38(20): 6472-6480, 2022 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35544954

RESUMEN

A hydrophobic surface or coating is required for surface protection, anti-fouling, adhesion, and other applications. For the achievements of hydrophobic properties, fluorine-based coatings, such as the introduction of trifluoromethyl or difluoromethylene groups, are conventionally employed. Recent developments in synthetic chemistry have indicated other organic fluoroalkyl groups that are suitable for achieving a more hydrophobic surface. In this study, we focused on the hydrophobic properties of the pentafluorosulfanyl (-SF5) group. We synthesized polymethacrylates with -SF5 groups or other functional groups (-CF3, -CH3, and -H) in their side chains and evaluated their hydrophobicity based on contact angles of water and ethylene glycol and the affinities of their films to water through neutron reflectivity measurements to demonstrate the superior hydrophobic properties of the -SF5 group. The water contact angle on the polymethacrylate film with -SF5 groups was larger, which suggested that the surface free energy was lower than that of the other polymethacrylate thin films with pendant side chains of -CF3, -CH3, and -H. In addition, the fitting analyses of the neutron reflectivity profiles of the thin polymer films in contact with air and water revealed the lowest affinity between water and the surface of polymethacrylate films with -SF5 groups among the films of the synthesized polymers. Thus, we demonstrated the potential of pentafluorosulfanyl groups as advanced hydrophobic groups.

11.
J Am Chem Soc ; 143(16): 6025-6036, 2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33857372

RESUMEN

Stimuli-responsive multifunctional mesoporous silica nanoparticles (MSNs) have been studied intensively during the past decade. A large variety of mesopore capping systems have been designed, initially to show that it could be done and later for biomedical applications such as drug delivery and imaging. On-command release of cargo molecules such as drugs from the pores can be activated by a variety of stimuli. This paper focuses on three noninvasive, biologically usable external stimuli: magnetism, ultrasound, and light. We survey the variety of MSNs that have been and are being used and assess capping designs and the advantages and drawbacks of the nanoplatforms' responses to the various stimuli. We discuss important recent advances, their basic mechanisms, and their requirements for stimulation. On the basis of our survey, we identify fundamental challenges and suggest future directions for research that will unleash the full potential of these fascinating nanosystems for clinical applications.


Asunto(s)
Luz , Campos Magnéticos , Nanoestructuras/química , Dióxido de Silicio/química , Nanomedicina Teranóstica , Ondas Ultrasónicas , Portadores de Fármacos/química , Humanos , Nanopartículas Magnéticas de Óxido de Hierro/química , Porosidad
12.
Langmuir ; 37(48): 14096-14104, 2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34808057

RESUMEN

Ultrasmall nanoparticles (USNPs) with sizes below 10 nm have shown great potentials in medical applications owing to their outstanding physical, chemical, optical, and biological properties. However, they suffer from a rapid renal clearance and biodegradation rate in the biological environment due to the small size. Liposomes are one of the most promising delivery nanocarriers for loading USNPs because of their excellent biocompatibility and lipid bilayer structure. Encapsulation of USNPs into liposomes in an efficient and controllable manner remains a challenge. In this study, we achieved a high loading of graphene quantum dots (GQDs, ∼4 nm), a typical USNP, into the aqueous core of liposomes (45.68 ± 1.44%), which was controllable by the pressure. The GQDs-loaded liposomes (GQDs-LPs) exhibited a very good aqueous stability for over a month. Furthermore, indocyanine green (ICG), an efficient near-infrared (NIR) photothermal agent, was introduced in the GQDs-LP system that could convert NIR laser energy into thermal energy and break down the liposomes, causing the release of GQDs in 6 min. Moreover, this NIR light-controlled release system (GQDs-ICG-LPs) also exhibited a good photothermal therapeutic performance in vitro, and 75% of cancer cells were killed at a concentration of 200 µg/mL. Overall, the successful development of the NIR light-controlled release system has laid a solid foundation for the future biomedical application of USNPs-loaded liposomes.


Asunto(s)
Grafito , Nanopartículas , Puntos Cuánticos , Liposomas , Fototerapia
13.
Hereditas ; 155: 16, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29308060

RESUMEN

BACKGROUND: Recent large-scale genome-wide association studies (GWAS) have showed that the neuronal calcium signaling has pivotal roles in schizophrenia (SCZ) in populations of European of ancestry. However, it is not known if calcium signaling pathway genes are also associated with SCZ in Han Chinese population. METHODS: Here we investigated the association between genetic variants in three calcium signaling pathway genes (CACNB2, CACNA1C and CACNA1I) and SCZ in 1615 SCZ cases and 1597 controls. RESULTS: A single nucleotide polymorphism (SNP) (rs4522708) in CACNA1I is significantly associated with SCZ in our Chinese sample (ORA allele = 1.19, corrected P = 0.042), suggesting that CACNA1I may also be a risk gene for SCZ in Chinese population. Of note, the risk allele (A allele) of SNP rs4522708 is same in European and Chinese populations. Meta-analysis of Chinese and European samples further strengthened the association of rs4522708 with SCZ (ORA allele = 1.074, P = 6.26 × 10-11). Expression analysis showed that CACNA1I was significantly up-regulated in hippocampus of SCZ cases compared with controls, implying that dysregulation of CACNA1I may have a role in schizophrenia pathogenesis. CONCLUSIONS: Our study suggests that CACNA1I is a risk gene for SCZ in Chinese population and provides further evidence that supports the potential role of neuronal calcium signaling in schizophrenia.


Asunto(s)
Canales de Calcio Tipo T/genética , Predisposición Genética a la Enfermedad , Esquizofrenia/genética , Alelos , Pueblo Asiatico/genética , Señalización del Calcio , Estudios de Casos y Controles , China , Genotipo , Humanos , Polimorfismo de Nucleótido Simple
14.
Small ; 13(43)2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29024478

RESUMEN

This study reports the preparation of a series of gadolinium-polydopamine nanoparticles (GdPD-NPs) with tunable metal loadings. GdPD-NPs are analyzed by nuclear magnetic relaxation dispersion and with a 7-tesla (T) magnetic resonance imaging (MRI) scanner. A relaxivity of 75 and 10.3 mM-1 s-1 at 1.4 and 7 T is observed, respectively. Furthermore, superconducting quantum interference device magnetometry is used to study intraparticle magnetic interactions and determine the GdPD-NPs consist of isolated metal ions even at maximum metal loadings. From these data, it is concluded that the observed high relaxivities arise from a high hydration state of the Gd(III) at the particle surface, fast rate of water exchange, and negligible antiferromagnetic coupling between Gd(III) centers throughout the particles. This study highlights design parameters and a robust synthetic approach that aid in the development of this scaffold for T1 -weighted, high relaxivity MRI contrast agents.

15.
Small ; 12(5): 668-77, 2016 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-26681255

RESUMEN

Amphiphilic triblock copolymers containing Fe(III) -catecholate complexes formulated as spherical- or cylindrical-shaped micellar nanoparticles (SMN and CMN, respectively) are described as new T1-weighted agents with high relaxivity, low cytotoxicity, and long-term stability in biological fluids. Relaxivities of both SMN and CMN exceed those of established gadolinium chelates across a wide range of magnetic field strengths. Interestingly, shape-dependent behavior is observed in terms of the particles' interactions with HeLa cells, with CMN exhibiting enhanced uptake and contrast via magnetic resonance imaging (MRI) compared with SMN. These results suggest that control over soft nanoparticle shape will provide an avenue for optimization of particle-based contrast agents as biodiagnostics. The polycatechol nanoparticles are proposed as suitable for preclinical investigations into their viability as gadolinium-free, safe, and effective imaging agents for MRI contrast enhancement.


Asunto(s)
Catecoles/química , Medios de Contraste/química , Imagen por Resonancia Magnética/métodos , Nanopartículas/química , Polímeros/química , Células HeLa , Humanos , Fenómenos Magnéticos , Micelas , Nanopartículas/ultraestructura , Espectroscopía de Protones por Resonancia Magnética
16.
J Pathol ; 232(4): 415-27, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24293274

RESUMEN

Colorectal cancer (CRC) is the third most common cancer in the USA. MicroRNAs play important roles in the pathogenesis of CRC. In this study, we investigated the role of miR-30b in CRC and found that its expression was significantly lower in CRC tissues than that in normal tissues. We showed that a low expression level of miR-30b was closely related to poor differentiation, advanced TNM stage and poor prognosis of CRC. Further experiments showed that over-expression of miR-30b suppressed CRC cell proliferation in vitro and tumour growth in vivo. Specifically, miR-30b promoted G1 arrest and induced apoptosis. Moreover, KRAS, PIK3CD and BCL2 were identified as direct and functional targets of miR-30b. MiR-30b directly targeted the 3'-untranslated regions of their mRNAs and repressed their expression. This study revealed functional and mechanistic links between miRNA-30b and oncogene KRAS, PIK3CD and BCL2 in the pathogenesis of CRC. MiR-30b not only plays important roles in the regulation of cell proliferation and tumour growth in CRC, but is also a potential prognostic marker or therapeutic target for CRC. Restoration of miR-30b expression may represent a promising therapeutic approach for targeting malignant CRC.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Genes Supresores de Tumor , MicroARNs/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas ras/metabolismo , Regiones no Traducidas 3' , Animales , Apoptosis , Sitios de Unión , Diferenciación Celular , Proliferación Celular , Fosfatidilinositol 3-Quinasa Clase I , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Biología Computacional , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Humanos , Estimación de Kaplan-Meier , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/genética , Persona de Mediana Edad , Estadificación de Neoplasias , Fosfatidilinositol 3-Quinasas/genética , Pronóstico , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas p21(ras) , ARN Mensajero/metabolismo , Transducción de Señal , Factores de Tiempo , Transfección , Carga Tumoral , Proteínas ras/genética
17.
J Glob Health ; 14: 04034, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38214316

RESUMEN

Background: Whether and to what extent multiple healthy lifestyles affect the longevity of people with disabilities, including those in basic activities of daily living, mobility, vision, hearing and cognition, is crucial to policymakers. We aimed to determine the impact of combined lifestyles on life expectancy (LE) lived with and without five disabilities. Methods: We recruited participants (n = 15 121 from the China Longitudinal Healthy Longevity Survey between 2008 and 2018. Healthy lifestyle levels were estimated from six factors: smoking, drinking, physical exercise, diet, cognitive activity, and sleep, which we categorised as favourable and unfavourable using the latent class growth mixture model throughout the follow-up period. We used Multi-state Markov models to assess the different disability stages of LE. Results: Of the total LE at age 65, older adults with a favourable lifestyle spent 59.60% (disability-free LE (DFLE) = 10.24 years) without five disabilities in combination, whereas those with unfavourable lifestyle spent 56.74% (DFLE = 7.28 years). Furthermore, the percentage of DFLE was 64.98 (7.71 years) and 68.38 (9.91 years) in males with unfavourable and favourable lifestyle levels, respectively, and 47.92 (6.62 years) and 55.12 (10.30 years) for females. Compared to older adults with low socioeconomic status (SES) and unfavourable lifestyle level, those with lower SES and favourable lifestyle level had more 3.77 years of DFLE, those with higher SES and unfavourable lifestyle level had more 1.94 years, as well as those with higher SES and favourable lifestyle level had more 5.10 years at age 65. Corresponding associations were found separately for each of the five individual disabilities. Conclusions: A favourable lifestyle level was associated with longer total LE along with a higher proportion of DFLE and may contribute to narrowing socioeconomic health inequalities. Policymakers should develop lifestyle interventions and scale up rehabilitation services in primary care, thereby delaying disabilities to later ages, especially in low- and middle-income countries.


Asunto(s)
Actividades Cotidianas , Personas con Discapacidad , Masculino , Femenino , Humanos , Anciano , Esperanza de Vida , Estilo de Vida Saludable , China
18.
J Biomater Sci Polym Ed ; 35(1): 45-62, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37773055

RESUMEN

Bacterial infections pose a significant threat to human health and safety, necessitating the urgent resolution of the problem through the development and implementation of highly effective antibacterial agents. However, the emergence of multidrug-resistant bacteria has diminished the satisfactory effectiveness of antibacterial treatments. To overcome this obstacle, we developed effective antibacterial agents by chemical reduction for inhibiting bacterial proliferation and inducing membrane damage. Specifically, four different types of chitosan/Ag nanoparticle (CS-AgNPs-i) (i-1, 2, 3, 4) complexes were synthesized by varying the quantity of chitosan added during the synthesis process. We found that the amount of CS does not affect the morphology and size of CS-AgNPs-i, which remained at approximately 20 nm and all CS-AgNPs were mostly spherical. The zeta potential measurements indicated that the surface of CS-AgNPs carries a positive charge. Notably, elevating the chitosan concentration led to a more pronounced antibacterial impact, particularly evident in its interaction with the peptidoglycan layer on the bacterial surface. Our experimental results undeniably establish the potent antibacterial efficacy of CS-AgNPs against both Escherichia coli and Staphylococcus aureus. Employing live/dead bacterial staining, we reveal the marked capability of CS-AgNPs to effectively hinder bacterial proliferation. Furthermore, our experimental investigations revealed that CS-AgNPs possess broad-spectrum antimicrobial activity. The results of in vitro cytotoxicity experiments substantiated the high biocompatibility of CS-AgNPs with elevated chitosan loading. The study provides valuable insights into the development of nano-antibacterial agents that exhibit significant potential as a substitute to replace traditional antibiotics for medical applications.


Asunto(s)
Quitosano , Nanopartículas del Metal , Humanos , Plata/farmacología , Plata/química , Nanopartículas del Metal/química , Quitosano/farmacología , Quitosano/química , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus , Escherichia coli , Pruebas de Sensibilidad Microbiana
19.
ACS Appl Mater Interfaces ; 16(3): 3001-3018, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38195388

RESUMEN

Synthetic melanin is a mimic of natural melanin analogue with intriguing properties such as metal-ion chelation, redox activity, adhesion, and broadband absorption. Melanin-inspired composite materials are formulated by assembly of melanin with other types of inorganic and organic components to target, combine, and build up the functionality, far beyond their natural capabilities. Developing efficient and universal methodologies to prepare melanin-based composite materials with unique functionality is vital for their further applications. In this review, we summarize three types of synthetic approaches, predoping, surface engineering, and physical blending, to access various melanin-inspired composite materials with distinctive structure and properties. The applications of melanin-inspired composite materials in free radical scavenging, bioimaging, antifouling, and catalytic applications are also reviewed. This review also concludes current challenges that must be addressed and research opportunities in future studies.

20.
Int J Biol Macromol ; 259(Pt 2): 129200, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38218266

RESUMEN

Food packaging films play a vital role in preserving and protecting food. However, due to their non-biodegradability, conventional packaging materials have led to significant environmental pollution. To overcome this hurdle, we have developed safe, innovative, sustainable and biodegradable packaging materials that can effectively extend the shelf life of food. In this study, two types of cellulose materials cellulose nanofibers (CNF) and carboxymethyl cellulose (CMC) with complementary roles were combined to prepare nanocellulose composite films with high transparency (90.3 %) of a certain thickness (30 ± 0.019 µm) by solution casting method, and their mechanical properties were further optimized by the addition of plasticizer-glycerol (Gly) and cross-linking agent-glutaraldehyde (GA), so as to maintain the strong tensile strength (≈112.60 MPa) and better malleability (4.12 %). In addition, we loaded the natural active agent tea polyphenols (TPs) with different concentrations to study the inhibition effect on E.coli and S.aureus and to simulate food packaging. Finally, we also found that the synthesized nanocellulose composite films can also achieve rapid degradation in a short time through soil burial, water flushing and immersion. The excellent performance demonstrated in this study provides reference value for further replacing petroleum-based materials with biomass materials in the field of food packaging.


Asunto(s)
Antibacterianos , Embalaje de Alimentos , Embalaje de Alimentos/métodos , Antibacterianos/farmacología , Agua , Glutaral , Celulosa
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