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1.
Small ; : e2404205, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39161199

RESUMEN

Highly-efficient and cost-effective electrocatalysts toward the oxygen evolution reaction (OER) are crucial for advancing sustainable energy technologies. Herein, a novel approach leveraging corrosion engineering is presented to facilitate the in situ growth of amorphous cobalt-iron hydroxides on nickel-iron foam (CoFe(OH)x-m/NFF) within a NaCl-CoCl2 aqueous solution. By adjusting the concentration of the solution, the compositions can tailored and morphologies of these hydroxides to optimize the OER electrocatalytic performance. Specifically, the CoFe(OH)x-500/NFF electrode manifests as distinctive 3D flower-like clusters composed of remarkably thin nanosheets, measuring a mere 1 nm in thickness. By virtue of the amorphous and ultrathin nanosheet structure, the CoFe(OH)x-500/NFF electrode exhibits superior OER activity, characterized by notably low overpotentials (η100, 274 mV) and an exceptionally small Tafel slope of 40.54 mV dec-1. Moreover, the electrode's performance remains robust, maintaining low overpotentials for 168 h at 100 mA cm-2. In situ Raman spectroscopy indicates that the hydroxides experience surface structural reconstruction and transform into high-valent CoFeO2 with active Co(IV)-O sites during the OER. Theoretical calculations underscore the critical role of the NiFe substrate in enhancing the electrode's OER activity by improving electrical conductivity and modifying the adsorption energy of reaction intermediates, thereby reducing the energy barrier for the reaction.

2.
Small ; 20(33): e2309651, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38530065

RESUMEN

The scientific community is pursuing significant efforts worldwide to develop environmentally viable film materials from biomass, particularly transparent, high-performance regenerated cellulose (RC) films, to replace traditional plastics. However, the inferior mechanical performance and hydrophilic nature of RC films are generally not suitable for use as a substitute for plastics in practical applications. Herein, lignin homogenization is used to synthesize high-performance composite films. The esterified lignin nanoparticles (ELNPs) with dispersible and binding advantages are prepared through esterification and nanometrization. In the presence of ELNPs, RC films exhibit a higher tensile strength (110.4 MPa), hydrophobic nature (103.6° water contact angle, 36.6% water absorption at 120 min, and 1.127 × 10-12 g cm cm-2 s-1 Pa-1 water vapor permeability), and exciting optical properties (high visible and low ultraviolet transmittance). The films further display antioxidant activity, oxygen barrier ability, and thermostability. The films completely biodegrade at 12 and 30% soil moisture. Overall, this study offers new insights into lignin valorization and regenerated cellulose composite films as novel bioplastic materials.

3.
Small ; : e2403221, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39012064

RESUMEN

Solar interfacial evaporation strategy (SIES) has shown great potential to deal with water scarcity and energy crisis. Biobased hydrogel derived interfacial evaporator can realize efficient evaporation due to the unique structure- properties relationship. As such, increasing studies have focused on water treatment or even potential accompanying advanced energy storage applications with respect of efficiency and mechanism of bio-based hydrogel derived interfacial evaporation from microscale to molecular scale. In this review, the interrelationship between efficient interfacial evaporator and bio-based hydrogel is first presented. Then, special attention is paid on the inherent molecular characteristics of the biopolymer related to the up-to-date studies of promising biopolymers derived interfacial evaporator with the objective to showcase the unique superiority of biopolymer. In addition, the applications of the bio-based hydrogels are highlighted concerning the aspects including water desalination, water decontamination atmospheric water harvesting, energy storage and conversion. Finally, the challenges and future perspectives are given to unveil the bottleneck of the biobased hydrogel derived SIES in sustainable water and other energy storage applications.

4.
Chem Rev ; 122(13): 11604-11674, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35653785

RESUMEN

Chitin, a fascinating biopolymer found in living organisms, fulfills current demands of availability, sustainability, biocompatibility, biodegradability, functionality, and renewability. A feature of chitin is its ability to structure into hierarchical assemblies, spanning the nano- and macroscales, imparting toughness and resistance (chemical, biological, among others) to multicomponent materials as well as adding adaptability, tunability, and versatility. Retaining the inherent structural characteristics of chitin and its colloidal features in dispersed media has been central to its use, considering it as a building block for the construction of emerging materials. Top-down chitin designs have been reported and differentiate from the traditional molecular-level, bottom-up synthesis and assembly for material development. Such topics are the focus of this Review, which also covers the origins and biological characteristics of chitin and their influence on the morphological and physical-chemical properties. We discuss recent achievements in the isolation, deconstruction, and fractionation of chitin nanostructures of varying axial aspects (nanofibrils and nanorods) along with methods for their modification and assembly into functional materials. We highlight the role of nanochitin in its native architecture and as a component of materials subjected to multiscale interactions, leading to highly dynamic and functional structures. We introduce the most recent advances in the applications of nanochitin-derived materials and industrialization efforts, following green manufacturing principles. Finally, we offer a critical perspective about the adoption of nanochitin in the context of advanced, sustainable materials.


Asunto(s)
Quitina , Nanoestructuras , Biopolímeros , Quitina/química , Nanoestructuras/química
5.
Analyst ; 148(17): 4219-4226, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37540136

RESUMEN

Nitric oxide (NO), as a critical transcellular messenger, participates in a variety of physiological and pathological processes. However, its real-time detection still faces challenges due to its short half-life and trace amounts. Here, MWCNTs@COF-366-Co was prepared by in situ growth of a cobalt porphyrin-based covalent organic framework (COF-366-Co) on multi-walled carbon nanotubes (MWCNTs), and a unique biosensing platform for ultrasensitive real-time NO determination was established. Remarkably, MWCNTs@COF-366-Co contains plenty of atomically arranged M-N4 active sites for electrocatalysis, which provides more efficient electron transfer pathways and resolves the random arrangement issue of active sites. COF-366-Co with a high surface area contains a large number of exposed active M-N4 sites, providing faster NO transport/diffusion and more efficient electron transfer pathways. Due to the synergy of atomic-level periodic structural features of COF-366-Co and high conductivity of MWCNTs, the MWCNTs@COF-366-Co electrochemical biosensor exhibited excellent NO determination performance in a wide range from 0.09 to 400 µM, with high sensitivity (8.9 µA µM-1 cm-2) and a low limit of detection (16 nM). Moreover, the biosensor has been successfully used to sensitively monitor NO molecules released from human umbilical vein endothelial cells (HUVECs). This research not only designed a multifunctional intelligent biosensor platform, but also provided a broad prospect for continuous dynamic monitoring of the activity of living cells and their released metabolites.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Nanotubos de Carbono , Porfirinas , Humanos , Nanotubos de Carbono/química , Estructuras Metalorgánicas/química , Óxido Nítrico , Porfirinas/química , Células Endoteliales de la Vena Umbilical Humana , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Límite de Detección
6.
Int J Mol Sci ; 24(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36675284

RESUMEN

The preparation of adsorbents with eco-friendly and high-efficiency characteristics is an important approach for pollutant removal, and can relieve the pressure of water shortage and environmental pollution. In recent studies, much attention has been paid to the potential of hydrothermal carbonization (HTC) from biomass, such as cellulose, hemicellulose, lignin, and agricultural waste for the preparation of adsorbents. Hereby, this paper summarizes the state of research on carbon adsorbents developed from various sources with HTC. The reaction mechanism of HTC, the different products, the modification of hydrochar to obtain activated carbon, and the treatment of heavy metal pollution and organic dyes from wastewater are reviewed. The maximum adsorption capacity of carbon from different biomass sources was also evaluated.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Biomasa , Colorantes , Celulosa , Adsorción , Temperatura
7.
J Nanobiotechnology ; 20(1): 312, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35794620

RESUMEN

BACKGROUND: Bacterial infection in wounds has become a major threat to human life and health. With the growth use of synthetic antibiotics and the elevated evolution of drug resistant bacteria in human body cells requires the development of novel wound curing strategies. Herein, a novel pH-responsive hydrogel (RPC/PB) was fabricated using poly(vinyl alcohol)-borax (PB) and natural antibiotic resveratrol grafted cellulose nanofibrils (RPC) for bacterial-infected wound management. RESULTS: In this hydrogel matrix, RPC conjugate was interpenetrated in the PB network to form a semi-interpenetrating network that exhibited robust mechanical properties (fracture strength of 149.6 kPa), high self-healing efficiency (> 90%), and excellent adhesion performance (tissue shear stress of 54.2 kPa). Interestingly, the induced RPC/PB hydrogel showed pH-responsive drug release behavior, the cumulative release amount of resveratrol in pH 5.4 was 2.33 times than that of pH 7.4, which was adapted well to the acidic wound microenvironment. Additionally, this RPC/PB hydrogel exhibited excellent biocompatibility and antioxidant effect. Moreover, in vitro and in vivo results revealed that such RPC/PB hydrogel had excellent antibacterial, skin tissue regeneration and wound closure capabilities. CONCLUSION: Therefore, the generated RPC/PB hydrogel could be an excellent wound dressing for bacteria-infected wound healing.


Asunto(s)
Celulosa , Hidrogeles , Antibacterianos/química , Antibacterianos/farmacología , Bacterias , Vendajes , Celulosa/farmacología , Humanos , Hidrogeles/química , Concentración de Iones de Hidrógeno , Resveratrol/farmacología
8.
Int J Mol Sci ; 23(23)2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36499668

RESUMEN

The application of silver nanoparticles (AgNPs) in antibacterial materials, glucose detection, etc., is of broad interest for researchers around the world. Nanocellulose with many excellent properties can be used as a carrier and stabilizer to assist in the synthesis of AgNPs. In this study, cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs) were used to assist in the synthesis of AgNPs under the reduction of glucose and detection of glucose concentration under different conditions. Transmission electron microscopy (TEM) analysis showed that the AgNPs in the nanocellulose-AgNPs (NC-AgNPs) system were roughly spherical and randomly distributed on the nanocellulose. In the whole reaction system, when the concentration of nanocellulose is 0.11 mg/mL, the concentration of silver ammonia solution is 0.6 mM, and the mixing time is 2.5 h, according to the UV-Vis analysis, the absorbance of CNF-AgNPs at 425 nm exhibited a good linear relationship (R2 = 0.9945) with the glucose concentration range (5-50 µM), while the absorbance of CNC-AgNPs at 420 nm showed a good linear relationship (R2 = 0.9956) with the glucose concentration range (5-35 µM). The synthesis of NC-AgNPs can be further developed into a sensor with higher sensitivity and higher stability for detecting glucose concentration and a material with antibacterial effects.


Asunto(s)
Glucosa , Nanopartículas del Metal , Plata , Antibacterianos/farmacología , Antibacterianos/química , Celulosa/química , Glucosa/análisis , Nanopartículas del Metal/química , Plata/química
9.
Int J Mol Sci ; 23(13)2022 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-35806106

RESUMEN

With the increasing demand for dissolving pulp, large quantities of hemicelluloses were generated and abandoned. These hemicelluloses are very promising biomass resources for preparing carbon spheres. However, the pore structures of the carbon spheres obtained from biomass are usually poor, which extensively limits their utilization. Herein, the carbon microspheres derived from hemicelluloses were prepared using hydrothermal carbonization and further activated with different activators (KOH, K2CO3, Na2CO3, and ZnCl2) to improve their electrochemical performance as supercapacitors. After activation, the specific surface areas of these carbon spheres were improved significantly, which were in the order of ZnCl2 > K2CO3 > KOH > Na2CO3. The carbon spheres with high surface area of 2025 m2/g and remarkable pore volume of 1.07 cm3/g were achieved, as the carbon spheres were activated by ZnCl2. The supercapacitor electrode fabricated from the ZnCl2-activated carbon spheres demonstrated high specific capacitance of 218 F/g at 0.2 A/g in 6 M KOH in a three-electrode system. A symmetric supercapacitor was assembled in 2 M Li2SO4 electrolyte, and the carbon spheres activated by ZnCl2 showed excellent electrochemical performance with high specific capacitance (137 F/g at 0.5 A/g), energy densities (15.4 Wh/kg), and good cyclic stability (95% capacitance retention over 2000 cycles).


Asunto(s)
Polisacáridos , Capacidad Eléctrica , Electrodos , Porosidad
10.
Int J Mol Sci ; 23(13)2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35806259

RESUMEN

Lignin nanoparticles, the innovative achievements in the development and utilization of lignin, combine the structural characteristics of nanomaterials and lignin molecules and have a wide range of applications. In this review, we summarize the methods for preparing lignin nanoparticles by solvent exchange method, mechanical method, biological enzymatic method, interface polymerization/crosslinking method, and spray freezing method, and emphatically introduce the application prospects of lignin nanoparticles in ultraviolet protection, antibacterial, nano-filler, drug delivery, and adsorption, aiming to provide a certain reference direction for additional high-value applications of lignin nanoparticles.


Asunto(s)
Nanopartículas , Nanoestructuras , Fenómenos Químicos , Lignina/química , Nanopartículas/química , Polimerizacion
11.
Anal Chem ; 93(26): 9064-9073, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34164977

RESUMEN

Peroxynitrite (ONOO-), a kind of reactive oxygen species, plays an indispensable role in many physiological processes. The stability and reactivity of ONOO- are significantly affected by the pH of the environment. A novel fluorescent probe RN-NA that can simultaneously respond to ONOO- and pH was proposed and constructed based on a rational-designed multifunctional fluorescence resonance energy transfer (FRET) platform. The RN-NA probe exhibited a remarkably different fluorescence change in response to ONOO- and pH. The fluorescence signals at 525 and 710 nm increased about 4-fold with a pH change from 8.0 to 3.0. The changes in fluorescence at 525 nm are mainly attributed to photo-induced electron transfer, and the fluorescence enhancement at 710 nm was mainly due to acid-induced open-closed circulation. In the presence of ONOO-, the fluorescence at 525 nm increased 5-fold, while the fluorescence at 710 nm was almost completely diminished. Up to 70-fold fluorescence enhancement was observed in the ratiometric channel F525/F710. In the cell imaging experiment, the intracellular pH was adjusted using H+/K+ ionophore and nigericin, and the endogenous ONOO- was generated by lipopolysaccharide (LPS) and γ-interferon (IFN-γ). The RN-NA probe can respond to cellular pH and endogenous ONOO- with remarkable fluorescence changes in both red/green and ratiometric channels.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Ácido Peroxinitroso , Colorantes Fluorescentes , Concentración de Iones de Hidrógeno
12.
BMC Womens Health ; 21(1): 39, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33509177

RESUMEN

BACKGROUND: There is a noticeable lack of systematic researches on evaluating the correlation between serum estrogen levels and changes in brain functional areas of perimenopausal women.The aim of this study is to investigate the regional spontaneous brain activity changes in perimenopausal women. METHODS: Based on the resting-state functional magnetic resonance imaging datasets acquired from 25 perimenopausal women and 20 healthy women of reproductive age, a two-sample t-test was performed on individual normalized regional homogeneity (ReHo) maps. Relationships between abnormal ReHo values and the self-rating anxiety scale (SAS), the self-rating depression scale (SDS) were investigated with Pearson correlation analysis. We also investigated the correlation between abnormal ReHo values and serum estrogen level. RESULTS: In the perimenopausal group, we found increased ReHo in the right posterior cerebellum (region 2), left middle frontal gyrus and left middle cingulate gyrus ([Formula: see text]). Additionally, the ReHo values in left middle frontal gyrus and leftt middle cingulate gyrus showed positively significant correlation with the SAS, SDS scores. On the contrary, there was no significant correlation between the ReHo value in right posterior cerebellum and SDS, SAS scores. In the perimenopausal group, the ReHo values in the left middle frontal gyrus and left middle cingulate gyrus were negatively correlated with the serum estrogen level ([Formula: see text]). CONCLUSION: The results of this preliminary study have suggested that abnormal spontaneous activities of multiple brain regions during resting state was already altered in perimenopausal women. Alterative activities might be related to emotional regulation deficits and cognitive impairment, and might potentially represent the neural mechanism underlying perimenopausal period.


Asunto(s)
Imagen por Resonancia Magnética , Perimenopausia , Encéfalo/diagnóstico por imagen , Femenino , Humanos
13.
Molecules ; 26(1)2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33406704

RESUMEN

Lignin nanomaterials have wide application prospects in the fields of cosmetics delivery, energy storage, and environmental governance. In this study, we developed a simple and sustainable synthesis approach to produce uniform lignin nanoparticles (LNPs) by dissolving industrial lignin in deep eutectic solvents (DESs) followed by a self-assembling process. LNPs with high yield could be obtained through nanoprecipitation. The LNPs were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and gel permeation chromatography (GPC). Distinct LNPs could be produced by changing the type of DES, lignin sources, pre-dropping lignin concentration, and the pH of the system. Their diameter is in the range of 20-200 nm and they show excellent dispersibility and superior long-term stability. The method of preparing LNPs from lignin-DES with water as an anti-solvent is simple, rapid, and environmentally friendly. The outcome aids to further the advancement of lignin-based nanotechnology.


Asunto(s)
Conservación de los Recursos Naturales , Lignina/química , Nanopartículas/química , Nanotecnología/métodos , Solventes/química , Hidrólisis
14.
J Cardiovasc Pharmacol ; 75(2): 168-173, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31663874

RESUMEN

BACKGROUND: Identifying patients with high risk of low response to statin therapy is important for optimization of lipid-lowering therapy. Cholesterol 7α-hydroxylase, a rate-limiting enzyme encoded by cytochrome P450 7A1 (CYP7A1) gene, is considered to be associated with statin efficacy. This study aimed to investigate the association between a novel CYP7A1 single nucleotide polymorphism rs3824260 and statin treatment response for hypercholesteremic patients in Chinese Han population. METHODS: A total of 336 subjects were prescribed with simvastatin for 12 weeks after enrollment. Plasma lipid parameters were measured at enrollment and after 12-week simvastatin treatment separately. Subjects were classified into high- and low-response groups depending on their total cholesterol, low-density lipoprotein cholesterol (LDL-C) and TG changes and increase or reduction groups according to their high-density lipoprotein cholesterol (HDL-C) levels changing after simvastatin treatment. The CYP7A1 rs3824260 was genotyped from blood samples with a SNaPshot assay. RESULTS: At baseline, the LDL-C level and TG level were significantly higher in the AA genotype, while the HDL-C level was significantly higher in the GG genotype of CYP7A1 rs3824260. Patients carrying AA genotype are at an increased risk of low response for LDL-C reduction (odds ratio = 2.295, 95% confidence interval = 1.164-4.524, P = 0.016). Furthermore, the GG genotype of rs3824260 was significantly associated with a high risk of HDL-C reduction response after simvastatin therapy (odds ratio = 2.240, 95% confidence interval = 1.137-4.413, P = 0.025). CONCLUSIONS: The CYP7A1 gene polymorphism rs3824260 is related to inappropriate response of simvastatin treatment for hypercholesterolemia patients in Chinese Han population.


Asunto(s)
Colesterol 7-alfa-Hidroxilasa/genética , LDL-Colesterol/sangre , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico , Variantes Farmacogenómicas , Polimorfismo de Nucleótido Simple , Simvastatina/uso terapéutico , Triglicéridos/sangre , Pueblo Asiatico , Biomarcadores/sangre , China , Colesterol 7-alfa-Hidroxilasa/metabolismo , Femenino , Humanos , Hipercolesterolemia/sangre , Hipercolesterolemia/diagnóstico , Hipercolesterolemia/genética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento
15.
Angew Chem Int Ed Engl ; 58(42): 14850-14854, 2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31410950

RESUMEN

Black liquor, an industrial waste product of papermaking, is primarily used as a low-grade combustible energy source. Despite its high lignin content, the potential utility of black liquor as a feedstock in products manufacturing, remains to be exploited. Demonstrated here in is the use of black liquor as a primary feed-stock for synthesizing graphene quantum dots that exhibit both up-conversion and photoluminescence when excited using visible/near-infrared radiation, thereby enabling the photosensitization of ultraviolet-absorbing TiO2 nanosheets. In addition, these graphene quantum dots can trap photo-generated electrons to realize the effective separation of electron-hole pairs. Together, these two processes facilitate the solar-powered generation of H2 from H2 O, and CO from H2 O-CO2 , using broadband solar radiation.

16.
Int J Mol Sci ; 18(12)2017 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-29168768

RESUMEN

A new functional biopolymer was synthesized through an ionic liquid-mediated homogeneous grafting of cinnamic anhydride to xylans. The ionic liquid used was 1-allyl-3-methylimidazolium chloride (AMIMCl) ionic liquid. Xylans with degrees of substitution (DS) between 0.11 and 0.57 were accessible in a completely homogeneous system by changing catalysts (NaOH, KOH and LiOH), time, reaction temperature, and cinnamic anhydride/xylan molar ratio. The chemical structure and the thermal stability of the derivatives were characterized by Fourier transform infrared spectroscopy (FT-IR), 13C-NMR spectroscopy, and thermogravimetry. The thermal stability of the derivatives was reduced compared with the original xylan. Possible applications of the cinnamic anhydride-acylated xylan derivatives include wet-end papermaking, organic-inorganic composite films, and hydrogels.


Asunto(s)
Cinamatos/química , Líquidos Iónicos/química , Xilanos/química , Adsorción , Catálisis , Esterificación , Hidrogeles/química , Iones/química , Espectroscopía de Resonancia Magnética , Metales Pesados/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termodinámica
17.
Int J Mol Sci ; 18(11)2017 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-29143790

RESUMEN

Deep eutectic solvents (DESs) are a potentially high-value lignin extraction methodology. DESs prepared from choline chloride (ChCl) and three hydrogen-bond donors (HBD)-lactic acid (Lac), glycerol, and urea-were evaluated for isolation of willow (Salix matsudana cv. Zhuliu) lignin. DESs types, mole ratio of ChCl to HBD, extraction temperature, and time on the fractionated DES-lignin yield demonstrated that the optimal DES-lignin yield (91.8 wt % based on the initial lignin in willow) with high purity of 94.5% can be reached at a ChCl-to-Lac molar ratio of 1:10, extraction temperature of 120 °C, and time of 12 h. Fourier transform infrared spectroscopy (FT-IR) , 13C-NMR, and 31P-NMR showed that willow lignin extracted by ChCl-Lac was mainly composed of syringyl and guaiacyl units. Serendipitously, a majority of the glucan in willow was preserved after ChCl-Lac treatment.


Asunto(s)
Lignina/química , Lignina/aislamiento & purificación , Salix/química , Solventes/química , Espectroscopía de Resonancia Magnética , Espectroscopía Infrarroja por Transformada de Fourier
18.
J Biol Chem ; 289(33): 22600-22613, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24982425

RESUMEN

Emerging evidence has shown that microRNAs have key roles in regulating various normal physiological processes, whereas their deregulated expression is correlated with various diseases. The miR-146 family includes miR-146a and miR-146b, with a distinct expression spectrum in different hematopoietic cells. Recent work indicated that miR-146a has a close relationship with inflammation and autoimmune diseases. miR-146-deficient mice have developed some abnormal hematopoietic phenotypes, suggesting the potential functions of miR-146 in hematopoietic development. In this study, we found that miR-146b was consistently up-regulated in both K562 and CD34(+) hematopoietic stem/progenitor cells (HSPCs) undergoing either erythroid or megakaryocytic differentiation. Remarkably, erythroid and megakaryocytic maturation of K562 cells was induced by excess miR-146b but inhibited by decreased miR-146b levels. More importantly, an mRNA encoding receptor tyrosine kinase, namely platelet-derived growth factor receptor α (PDGFRA), was identified and validated as a direct target of miR-146b in hematopoietic cells. Gain-of-function and loss-of-function assays showed that PDGFRA functioned as a negative regulator in erythroid and megakaryocytic differentiation. miR-146b could ultimately affect the expression of the GATA-1 gene, which is regulated by HEY1 (Hairy/enhancer-of-split related with YRPW motif protein 1), a transcriptional repressor, via inhibition of the PDGFRA/JNK/JUN/HEY1 pathway. Lentivirus-mediated gene transfer also demonstrated that the overexpression of miR-146b promoted erythropoiesis and megakaryocytopoiesis of HSPCs via its regulation on the PDGFRA gene and effects on GATA-1 expression. Moreover, we confirmed that the binding of GATA-1 to the miR-146b promoter and induction of miR-146b during hematopoietic maturation were dependent on GATA-1. Therefore, miR-146b, PDGFRA, and GATA-1 formed a regulatory circuit to promote erythroid and megakaryocytic differentiation.


Asunto(s)
Células Eritroides/metabolismo , Eritropoyesis/fisiología , Células Madre Hematopoyéticas/metabolismo , Megacariocitos/metabolismo , MicroARNs/metabolismo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Trombopoyesis/fisiología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular/fisiología , Células Eritroides/citología , Factor de Transcripción GATA1/genética , Factor de Transcripción GATA1/metabolismo , Células Madre Hematopoyéticas/citología , Humanos , Células K562 , Megacariocitos/citología , Ratones , MicroARNs/genética , Regiones Promotoras Genéticas/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Transducción de Señal/fisiología , Regulación hacia Arriba/fisiología
19.
Blood ; 119(21): 4992-5004, 2012 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-22493297

RESUMEN

Although microRNAs (miRNAs) are increasingly linked to various physiologic processes, including hematopoiesis, their function in the myeloid development is poorly understood. We detected up-regulation of miR-29a and miR-142-3p during myeloid differentiation in leukemia cell lines and CD34(+) hematopoietic stem/progenitor cells. By gain-of-function and loss-of-function experiments, we demonstrated that both miRNAs promote the phorbol 12-myristate 13-acetate-induced monocytic and all-trans-retinoic acid-induced granulocytic differentiation of HL-60, THP-1, or NB4 cells. Both the miRNAs directly inhibited cyclin T2 gene, preventing the release of hypophosphorylated retinoblastoma and resulting in induction of monocytic differentiation. In addition, a target of miR-29a, cyclin-dependent kinase 6 gene, and a target of miR-142-3p, TGF-ß-activated kinase 1/MAP3K7 binding protein 2 gene, are involved in the regulation of both monocytic and granulocytic differentiation. A significant decrease of miR-29a and 142-3p levels and an obvious increase in their target protein levels were also observed in blasts from acute myeloid leukemia. By lentivirus-mediated gene transfer, we demonstrated that enforced expression of either miR-29a or miR-142-3p in hematopoietic stem/progenitor cells from healthy controls and acute myeloid leukemia patients down-regulated expression of their targets and promoted myeloid differentiation. These findings confirm that miR-29a and miR-142-3p are key regulators of normal myeloid differentiation and their reduced expression is involved in acute myeloid leukemia development.


Asunto(s)
Diferenciación Celular/genética , Leucemia Mieloide Aguda/genética , MicroARNs/fisiología , Células Mieloides/fisiología , Antineoplásicos/farmacología , Carcinógenos/farmacología , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Regulación Leucémica de la Expresión Génica/fisiología , Células HEK293 , Células HL-60 , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , MicroARNs/genética , MicroARNs/metabolismo , Células Mieloides/efectos de los fármacos , Células Mieloides/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Transfección , Tretinoina/farmacología
20.
Int J Biol Macromol ; 276(Pt 2): 133910, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39029837

RESUMEN

Traditional packaging materials feed the growing global food protection. However, these packaging materials are not conducive to environment and have not the ability to kill bacteria. Herein, a green and simple strategy is reported for food packaging protection and long-term antibacterial using carboxymethylcellulose-based photothermal film (CMC@CuS NPs/PVA) that consists of carboxymethyl cellulose (CMC) immobilized copper sulfide nanoparticles (CuS NPs) and polyvinyl alcohol (PVA). With satisfied oxygen transmittance (0.03 cc/m2/day) and water vapor transmittance (163.3 g/m2/day), the tensile strength, tear strength and burst strength reached to 3401.2 N/m, 845.7 mN and 363.6 kPa, respectively, which could lift 4.5 L of water. The composite film had excellent photothermal conversion efficiency and photothermal stability. Under the irradiation of near infrared (NIR), it can rapidly heated up to 197 °C within 25 s. The antibacterial analysis showed that the inhibition rate of composite film against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) could all reach >99 %. Furthermore, the synthesized CuS NPs was well immobilized and the residual rate of copper kept 98.7 % after 10 days. Noticeably, the composite film can preserve freshness of strawberries for up to 6 days. Therefore, the composite film has potential application for food antibacterial protection.

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