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1.
Angew Chem Int Ed Engl ; : e202410932, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39283272

RESUMEN

Oxide derived catalyst displays outstanding catalytic activity and selectivity in electrochemical carbon dioxide reduction reaction (CO2RR), in which, it is found that residue oxygen atoms play a pivotal role in regulating the catalyst's electronic structure and thus the CO2RR process. Unfortunately, the intrinsic thermodynamic instability of oxygen atoms in oxide derived catalyst under cathodic CO2RR potentials makes it unstable during continuous electrolysis, greatly hindering its practical industrial applications. In this work, we develop a pulsed-bias technique that is able to dynamically stabilize the residue oxygen atoms in oxide derived catalyst during electrochemical CO2RR. As a result, the oxide derived catalyst under pulsed bias exhibits super catalytic stability in catalyzing electrochemical CO2RR, while keeping excellent catalytic activity and selectivity.

2.
Small ; 19(9): e2206258, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36538746

RESUMEN

In view of high-performance, multifunctional, and low-carbon development of infrastructures, there is a growing demand for smart engineering materials, making infrastructures intelligent. This paper reports a new-generation self-sensing cementitious composite (SSCC) incorporated with a hierarchically structured carbon fiber (CF)-carbon nanotube (CNT) composite filler (CF-CNT), which is in situ synthesized by directly growing CNT on CF. Various important factors including catalyst, temperature, and gas composition are considered to investigate their kinetic and thermodynamic influence on CF-CNT synthesis. The reciprocal architecture of CF-CNT not only alleviates the CNT aggregation, but also significantly improves the interfacial bonding between CF-CNT and matrix. Due to the synergic and spatially morphological effects of CF-CNT, that is, the formation of widely distributed multiscale reinforcement networks, SSCCs with CF-CNTs exhibit high mechanical properties and electrical conductivity as well as excellent self-sensing performances, particularly enhanced sensing repeatability. Moreover, the SSCCs with CF-CNTs are integrated into a full-scale maglev girder to devise a smart system for crack development monitoring. The system demonstrates high sensitivity and fidelity to capture the initiation of cracks/damage, as well as progressive and sudden damage events until the complete failure of the maglev girder, indicating its considerable potential for structural health monitoring of infrastructures.

3.
Nanotechnology ; 34(11)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36595250

RESUMEN

Fe-Co alloys exhibit an excellent saturation magnetization, which makes them become a potential candidate for the high property magnetic particles in magnetorheological fluids (MRFs). How to decrease their coercivity and residual magnetization without sacrificing the saturation magnetization is a crucial problem to be solved. In this study, Fe-Co nanoparticles were prepared by DC arc discharge and further disposed through low temperature annealing in Ar atmosphere. The successful synthesis of Fe-Co nanoparticles was proved by x-ray diffraction and EDS. The vibrating sample magnetometer results revealed that the prepared Fe-Co nanoparticles had a saturation magnetization of 208 emu g-1, while the coercivity and remanent magnetization were 58 Oe and 5.8 emu g-1, respectively. The MR properties of Fe-Co nanoparticles based MRFs (FeCoNP-MRFs) with 10% particles by volume fraction were systematically investigated. The FeCoNP-MRFs showed up to 4.61 kPa dynamic shear stress at 436 kA m-1magnetic field and an excellent reversibility. The MR properties of FeCoNP-MRFs were fitted well by Bingham and power law model, and described by Seo-Seo and Casson fluid model. Meanwhile, the sedimentation ratio of FeCoNP-MRFs was still 87.3% after 72 h, indicating an excellent sedimentation stability.

4.
BMC Womens Health ; 21(1): 134, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33789656

RESUMEN

BACKGROUND: This study aimed to investigate the clinical and pathological characteristics, and the recurrence and prognostic factors of borderline ovarian tumors (BOTs). METHODS: The data of 286 patients admitted to hospital and followed up for more than ten months were analyzed retrospectively to study the clinicopathological characteristics and related factors of recurrence. RESULTS: The median age of the patients was 42.06 ± 14.97 years, and the duration of the follow-up ranged from 10-109 months. During the follow-up period, 40 patients had a recurrence. Of these patients, 36 were ≤ 40 years, and patients with premenopausal recurrence accounted for 20.5% (36/176). In patients undergoing conservative treatment or radical operations, the recurrence rates were 21.3% and 1.8%, respectively, and they were 13.4% (36/268) in patients at Federation International of Gynecology and Obstetrics (FIGO) stage I, and 22.2% (4/18) in patients at an advanced stage. Postoperative pathology revealed that 40 patients had micropapillary tumors, among whom ten patients (25%) had a recurrence, and 19 patients had complications with interstitial infiltration. Of these 19 patients, six had a recurrence (31.5%). Another 22 patients had complications with calcified sand bodies; among these, eight patients (36.4%) had a recurrence. All the differences were statistically significant (P < 0.05). There were four cancer-related deaths during the follow-up period. Late FIGO stage, conservative operation, and a high level of carbohydrate antigen 125 (CA125) were independent risk factors for the recurrence of BOTs. CONCLUSION: BOTs usually occur in women under 40 years, have an occult onset, and half of the patients have no obvious clinical manifestations. Serum CA125 level can be used as a tumor marker to detect BOTs and the risk of its recurrence. Operation mode and FIGO stage are important independent factors for the recurrence of BOTs.


Asunto(s)
Neoplasias Ováricas , Biomarcadores de Tumor , Antígeno Ca-125 , Niño , Preescolar , Femenino , Humanos , Lactante , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/patología , Embarazo , Pronóstico , Estudios Retrospectivos
5.
Soft Matter ; 14(18): 3504-3509, 2018 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-29670977

RESUMEN

The field-induced storage modulus is an important parameter for the applications of magnetorheological (MR) elastomers. In this study, a model mechanism is established to analyze the potential benefits of using flower-like particles as the active phase compared with the benefits of using conventional spherical particles. To verify the model mechanism and to investigate the difference in dynamic viscoelasticity between MREs with spherical particles and flower-like particles, flower-like cobalt particles and spherical cobalt particles with similar particle sizes and magnetic properties are synthesized and used as the active phase to prepare MR elastomers. As the model predicts, MREs with flower-like cobalt particles present a higher crosslink density and enhanced interfacial bond strength, which leads to a higher storage modulus and higher loss modulus with respect to MREs with spherical cobalt particles. The tunable range of the field-induced storage modulus of MREs is also improved upon using the flower-like particles as the active phase.

6.
Soft Matter ; 14(10): 1917-1924, 2018 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-29468233

RESUMEN

Superparamagnetic Fe3O4 nanoparticles were successfully deposited on the surface of MoS2 nanosheets (Fe3O4/MoS2) by a sonochemical method and the obtained Fe3O4/MoS2 nanocomposites were used as a promising candidate for a magnetorheological (MR) fluid. This MR fluid was prepared from the Fe3O4/MoS2 nanocomposites and its corresponding MR performances were examined using a rotational rheometer. The MR fluid based on Fe3O4/MoS2 showed typical MR effects with increasing viscosity, shear stress, yield stress and dynamic shear modulus depending on the applied magnetic fields. Compared with commercial carbonyl iron (CI) particles, the sedimentation stability of the Fe3O4/MoS2-MR fluid was greatly improved because of its unique two-dimensional structure and the reduced fluid-particle density mismatch. Therefore, the prepared Fe3O4/MoS2-based MR fluid with typical MR effects and good sedimentation stability would have great potential in practical applications.

7.
Soft Matter ; 13(32): 5409-5420, 2017 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-28702616

RESUMEN

As a smart soft material, electrorheological elastomers (EREs) present tunable damping capacity and adjustable dynamic moduli on applying an electric field. Most of the previous studies focused on their dynamic moduli, while the damping performance has been neglected. In this study, the damping capacity of two kinds of EREs containing bare TiO2 and silane coupling agent-modified TiO2 particles were tested and compared as a function of strain amplitude. The results indicate that the modified TiO2 particle filled EREs present lower damping capacity when the strain amplitude exceeds 10%, indicating that the interfacial friction between the modified TiO2 particles and the matrix is decreased due to the stronger interface strength. A theoretical model is developed to describe the damping behaviour of the EREs, which is divided into the intrinsic damping, the interface damping and the electric field induced damping. The experimental results are well matched with the damping curves given by this model under various electric field strengths, and the difference between the damping capacity of the ERE containing bare TiO2 particles and the one containing modified TiO2 particles can be mainly ascribed to the effect of weakly and strongly bonded interface damping.

8.
Poult Sci ; 103(2): 103294, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38042040

RESUMEN

The bursa of Fabricius (BF) is pivotal for B lymphocyte ontogenesis. In the present investigation, a novel bursal peptide, designated BP7, was extracted from BF and was found to stimulate colony-forming unit pre-B (CFU pre-B) formation at various concentrations (1 µg/mL, P < 0.05; 5 µg/mL, P < 0.05; 25 µg/mL, P < 0.05). Moreover, BP7 modulated B cell differentiation pathways. The immunoregulatory potential of BP7 was further assessed in avian and murine models subjected to immunization with inactivated avian influenza virus (AIV, H9N2 subtype). BP7 significantly augmented AIV-specific antibody levels (Prime immunization: 5 mg/kg, P < 0.05; Boost immunization: 0.4, 1, and 5 mg/kg, P < 0.05) and cytokine secretion in the avian model (IL-4 and IFN-γ: 0.4, 1, and 5 mg/kg, P < 0.05). Similarly, in the murine model, AIV-specific antibody levels (Prime and Boost immunization: 0.4, 1, and 5 mg/kg, P < 0.05) and cytokine production (IL-4 and IFN-γ: 0.4, 1, and 5 mg/kg, P < 0.05) were notably enhanced. This study offers novel insights into the mechanisms underlying B cell maturation and holds implications for future immunopharmacological interventions.


Asunto(s)
Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Enfermedades de los Roedores , Animales , Ratones , Interleucina-4/metabolismo , Pollos , Péptidos/metabolismo , Bolsa de Fabricio , Enfermedades de los Roedores/metabolismo
9.
Biomolecules ; 14(9)2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39334881

RESUMEN

Porcine epidemic diarrhea virus (PEDV) has caused significant economic losses to the pig farming industry in various countries for a long time. Currently, there are no highly effective preventive or control measures available. Research into the pathogenic mechanism of PEDV has shown that it primarily causes infection by binding the S protein to the CD13 (APN) receptor on the membrane of porcine intestinal epithelial cells. The S1 region contains three neutralization epitopes and multiple receptor-binding domains, which are closely related to viral antigenicity and ad-sorption invasion. Nanobodies are a type of single-domain antibody that have been discovered in recent years. They can be expressed on a large scale through prokaryotic expression systems, which makes them cost-effective, stable, and less immunogenic. This study used a phage display library of nanobodies against the PEDV S1 protein. After three rounds of selection and enrichment, the DNA sequence of the highly specific nanobody S1Nb1 was successfully obtained. To obtain soluble nanobody S1Nb1, its DNA sequence was inserted into the vector Pcold and a solubility-enhancing SUMO tag was added. The resulting recombinant vector, Pcold-SUMO-S1Nb1, was then transformed into E. coli BL21(DE3) to determine the optimal expression conditions for the nanobody. Following purification using Ni-column affinity chromatography, Western blot analysis confirmed the successful purification of S1Nb1 carrying the solubility-enhancing tag. ELISA results demonstrated a strong affinity between the S1Nb1 nanobody and PEDV S1 protein.


Asunto(s)
Escherichia coli , Virus de la Diarrea Epidémica Porcina , Anticuerpos de Dominio Único , Virus de la Diarrea Epidémica Porcina/inmunología , Virus de la Diarrea Epidémica Porcina/genética , Anticuerpos de Dominio Único/inmunología , Anticuerpos de Dominio Único/genética , Anticuerpos de Dominio Único/aislamiento & purificación , Anticuerpos de Dominio Único/química , Escherichia coli/genética , Escherichia coli/metabolismo , Animales , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Porcinos , Biblioteca de Péptidos , Expresión Génica
10.
Adv Sci (Weinh) ; : e2407765, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377309

RESUMEN

The shear yield strength, sedimentation stability and zero-field viscosity of magnetorheological fluids (MRFs) are crucial for practical vibration damping applications, yet achieving a balanced combination of these performances remains challenging. Developing MRFs with excellent comprehensive performance is key to advancing smart vibration damping technologies further. Theoretically, incorporating a multiscale particle system and leveraging synergistic effects between their can somewhat enhance MRFs' performance. However, this approach often faces issues such as insignificant increases in shear yield strength and excessive rise in zero-field viscosity. In response, this study employs a DC arc plasma method to synthesize a high magnetic permeability, low coercivity submicron FeNi particles, and further develops a novel CIPs-FeNi bidisperse MRFs. The introduction of submicron FeNi particles not only significantly enhances the shear2019 yield strength of MRFs under low magnetic fields but also promotes improvements in sedimentation stability and redispersibility without excessively increasing viscosity. Comprehensive performance analysis is conducted to explore the optimal content ratio, and detailed mechanisms for the enhancement of performance are elucidated through analysis of parameters such as chain-like structure, magnetic flux density and friction coefficient. Most importantly, the superior comprehensive performance combined with straightforward fabrication methods significantly enhances the engineering applicability of the CIPs-FeNi bidisperse MRFs.

11.
Polymers (Basel) ; 16(18)2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39339025

RESUMEN

Currently available intraocular lenses (IOLs) on the market often differ significantly in elastic modulus compared to the natural human lens, which impairs their ability to respond effectively to the tension of the ciliary muscles for focal adjustment after implantation. In this study, we synthesized a polyacrylamide-sodium acrylate hydrogel (PAH) through the cross-linking polymerization of acrylamide and sodium acrylate. This hydrogel possesses excellent biocompatibility and exhibits several favorable properties. Notably, the hydrogel demonstrates high transparency (94%) and a refractive index (1.41 ± 0.07) that closely matches that of the human lens (1.42). Additionally, it shows strong compressive strength (14.00 kPa), good extensibility (1400%), and an appropriate swelling ratio (50 ± 2.5%). Crucially, the tensile modulus of the hydrogel is 2.07 kPa, which closely aligns with the elastic modulus of the human lens (1.70-2.10 kPa), enabling continuous focal adjustment under the tension exerted by the ciliary muscles.

12.
Viruses ; 16(2)2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38400007

RESUMEN

In the realm of clinical practice, nucleoside analogs are the prevailing antiviral drugs employed to combat feline herpesvirus-1 (FHV-1) infections. However, these drugs, initially formulated for herpes simplex virus (HSV) infections, operate through a singular mechanism and are susceptible to the emergence of drug resistance. These challenges underscore the imperative to innovate and develop alternative antiviral medications featuring unique mechanisms of action, such as viral entry inhibitors. This research endeavors to address this pressing need. Utilizing Bio-layer interferometry (BLI), we meticulously screened drugs to identify natural compounds exhibiting high binding affinity for the herpesvirus functional protein envelope glycoprotein B (gB). The selected drugs underwent a rigorous assessment to gauge their antiviral activity against feline herpesvirus-1 (FHV-1) and to elucidate their mode of action. Our findings unequivocally demonstrated that Saikosaponin B2, Punicalin, and Punicalagin displayed robust antiviral efficacy against FHV-1 at concentrations devoid of cytotoxicity. Specifically, these compounds, Saikosaponin B2, Punicalin, and Punicalagin, are effective in exerting their antiviral effects in the early stages of viral infection without compromising the integrity of the viral particle. Considering the potency and efficacy exhibited by Saikosaponin B2, Punicalin, and Punicalagin in impeding the early entry of FHV-1, it is foreseeable that their chemical structures will be further explored and developed as promising antiviral agents against FHV-1 infection.


Asunto(s)
Infecciones por Herpesviridae , Taninos Hidrolizables , Ácido Oleanólico/análogos & derivados , Saponinas , Varicellovirus , Animales , Gatos , Humanos , Antivirales/farmacología , Antivirales/uso terapéutico , Infecciones por Herpesviridae/veterinaria
13.
Biomolecules ; 14(1)2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38254686

RESUMEN

Antibiotic therapy effectively addresses Escherichia coli-induced enteric diseases, but its excessive utilization results in microbial imbalance and heightened resistance. This study evaluates the therapeutic efficacy of orally administered poly (lactic-co-glycolic acid) (PLGA)-loaded antimicrobial peptide OH-CATH30 microspheres in murine bacterial enteritis. Mice were categorized into the healthy control group (CG), untreated model group (MG), OH-CATH30 treatment group (OC), PLGA-OH-CATH30 treatment group (POC), and gentamicin sulfate treatment group (GS). Except for the control group, all other experimental groups underwent Escherichia coli-induced enteritis, followed by a 5-day treatment period. The evaluation encompassed clinical symptoms, intestinal morphology, blood parameters, inflammatory response, and gut microbiota. PLGA-OH-CATH30 microspheres significantly alleviated weight loss and intestinal damage while also reducing the infection-induced increase in spleen index. Furthermore, these microspheres normalized white blood cell count and neutrophil ratio, suppressed inflammatory factors (IL-1ß, IL-6, and TNF-α), and elevated the anti-inflammatory factor IL-10. Analysis of 16S rRNA sequencing results demonstrated that microsphere treatment increased the abundance of beneficial bacteria, including Phocaeicola vulgatus, in the intestinal tract while concurrently decreasing the abundance of pathogenic bacteria, such as Escherichia. In conclusion, PLGA-OH-CATH30 microspheres have the potential to ameliorate intestinal damage and modulate the intestinal microbiota, making them a promising alternative to antibiotics for treating enteric diseases induced by Escherichia coli.


Asunto(s)
Antibacterianos , Péptidos Antimicrobianos , Animales , Ratones , Microesferas , ARN Ribosómico 16S , Antibacterianos/farmacología , Escherichia coli
14.
J Phys Chem B ; 128(1): 393-404, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38166404

RESUMEN

Coarse-grained modeling shows potential in exploring the thermo-mechanical behaviors of polymers applied in harsh conditions such as cryogenic environment, but its accuracy in simulating fracture behaviors of highly cross-linked epoxy thermosets is largely limited due to the complex molecular structures of the cross-linked networks. We address this fundamental problem by developing a CG modeling method where the backbones and electrostatic interaction (EI) contributions in the cross-linked networks are retained, and thus the potentials of the CG model can be directly extracted, or parametrized on the basis of, existing all-atomistic (AA) force fields. A multilevel parametrization procedure was adopted, where the bond potentials were parametrized relying on the results of density functional theory (DFT) simulation, whereas the nonbond potentials were parametrized by renormalizing the cohesive interaction strength. Remarkably, the CG model can reproduce stress-strain responses highly consistent with the AA simulation results at multiple stages, including elastic deformation, yielding, plastic flow, strain hardening, etc., and the straightforward parametrization procedure can be easily transferred to different materials and thermodynamic conditions. The CG modeling method was then used to build a large-scale representative volume element (RVE) to investigate the microscopic fracture behavior of an epoxy thermoset. It has been discovered that EI contributions play a significant role in generating correct mechanical responses and fracture morphologies. The influences of temperature (i.e., from room to cryogenic temperatures) and strain rates were discussed, and the fracture morphology in the RVE was unveiled and analyzed in a quantitative manner.

15.
Biomolecules ; 13(8)2023 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-37627308

RESUMEN

Bacterial keratitis in animals presents challenges due to ocular structural barriers, hindering effective drug delivery. In this study, we used biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) to encapsulate the naturally occurring antimicrobial peptide OH-CATH30, an alternative to conventional antibiotics, for the treatment of bacterial keratitis in animals. Microspheres (MS) were prepared using a modified water-in-oil-in-water (W/O/W) double-emulsion method with optimized osmotic pressure. We conducted comprehensive evaluations, including in vitro characterization, encapsulation efficiency determination, in vitro release kinetics, and in vivo/vitro assessments of irritation and bacterial inhibition. The optimized method yielded microspheres with impressive encapsulation efficiency of 75.2 ± 3.62% and a loading capacity of 18.25 ± 5.73%, exhibiting a well-defined particle size distribution (200-1000 nm) and a ζ-potential of -17.3 ± 1.91 mV. The microspheres demonstrated initial burst release followed by sustained and controlled release in vitro. Both in vitro and in vivo tolerance tests confirmed the biocompatibility of the drug-loaded microspheres, as they did not elicit significant irritation in ocular tissues. Remarkable antibacterial effects were observed in both in vitro and in vivo experiments. Our developed PLGA microspheres show promise as an alternative therapeutic option for topical administration in managing keratitis, offering exceptional drug delivery capabilities, improved bioavailability, and potent antibacterial efficacy.


Asunto(s)
Queratitis , Animales , Microesferas , Queratitis/tratamiento farmacológico , Ojo , Antibacterianos/farmacología , Péptidos Antimicrobianos
16.
Polymers (Basel) ; 15(23)2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-38231916

RESUMEN

Intrauterine adhesions (IUA) has become one of the main causes of female infertility. How to effectively prevent postoperative re-adhesion has become a clinical challenge. In this study, a mussel-inspired dual-network hydrogel was proposed for the postoperative anti-adhesion of IUA. First, a calcium alginate/polyacrylamide (CA-PAM) hydrogel was prepared via covalent and Ca2+ cross-linking. Benefiting from abundant phenolic hydroxyl groups, polydopamine (PDA) was introduced to further enhance the adhesion ability and biocompatibility. This CA-PAM hydrogel immersed in 10 mg/mL dopamine solution possessed remarkable mechanical strength (elastic modulus > 5 kPa) and super stretchability (with a breaking elongation of 720%). At the same time, it showed excellent adhesion (more than 6 kPa). Surprisingly, the coagulation index of the hydrogel was 27.27 ± 4.91, demonstrating attractive coagulation performance in vitro and the potential for rapid hemostasis after surgery.

17.
Front Microbiol ; 14: 1153365, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37362941

RESUMEN

Antibacterial peptides are endogenous polypeptides produced by multicellular organisms to protect the host against pathogenic microbes, they show broad spectrum antimicrobial activities against various microorganisms and possess low propensity for developing resistance. The purpose of this study is to develop recombinant antibacterial peptide cathelicidin-BF by genetic engineering and protein engineering technology, and study its antibacterial activity in vitro and in vivo, so as to provide reference for the production and application of recombinant antibacterial peptide cathelicidin-BF. In this study, on account of Pichia pastoris eukaryotic expression system, we expressed and prepared antibacterial peptide cathelicidin-BF. Then, the minimum inhibitory concentration of antibacterial peptide cathelicidin-BF and the comparison with the antibacterial activity of antibiotics were determined through the antibacterial experiment in vitro. Chickens as infection model were used to verify the antibacterial peptide activity in vivo. The results show that the bacteriostatic ability of antibacterial peptide cathelicidin-BF is similar to that of antibiotics in certain concentration, and can reach the treatment level of antibiotics. Although the mode of administration of antibacterial peptide is still limited, this study can provide reference for the future research of antibacterial peptide.

18.
ACS Appl Mater Interfaces ; 15(14): 17969-17977, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36989317

RESUMEN

Self-powered implantable medical devices (IMDs) without any external power supply are desired in a growing number of situations. Glucose fuel cells (GFCs) that convert the chemical energy of intrinsic glucose and oxygen into electricity are promising technology to achieve this goal. Herein, a Pt nanoflower (Pt NF) catalyst is prepared by using a facile one-step reduction method and employed as the anode catalyst for abiotic GFCs in a neutral environment at a physiological concentration of glucose. The Pt NF catalyst exhibits high electrocatalytic activity, catalytic selectivity, and good durability in the electrochemical analysis. The Pt NF's rapid linear current response to the variation of glucose concentration within a wide range also makes it a promising material for glucose sensors. A GFC with two chambers fabricated with a Pt NF catalyst-decorated carbon paper (Pt NFs/CP) anode and a Pt sheet cathode generates a maximum power density (Pmax) of 13.8 µW cm-2, an open-circuit voltage (VOC) of 819.5 mV, and a short-circuit current density (JSC) of 0.12 mA cm-2, which makes it a viable candidate for application in self-powered devices.

19.
Chem Asian J ; 18(6): e202201198, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36782101

RESUMEN

The development of flexible lithium-ion batteries (FLIBs) is restrained by traditional rigidity anodes. Carbon nanofiber (CNF) is a promising anode material owing to its high specific surface and superior ion transportation capability. However, the low amount of active material loaded on the CNFs and the poor stability during long cycling restrain their applications. Herein, a SiO2 @carbon sphere/SiO2 -CNF self-standing anode was prepared via alternate electrospraying-electrospinning. The SiO2 content of the anode was increased through the electrospraying SiO2 @carbon spheres layers, and the electrospun SiO2 -CNFs as robust layers enhanced the stability of the anode. The self-standing anode exhibited 633 mA h g-1 in the initial cycle and maintained a 70% Coulomb efficiency for 1000 cycles at a current density of 100 mA g-1 , which could be applied in FLIB and other electrochemical storage devices.

20.
Int J Biol Macromol ; 247: 125624, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37392919

RESUMEN

Severe bone defects that extend beyond a critical size do not heal on their own, increasing the risk of complications and leading to poor outcomes for patients. Healing is a highly coordinated and complex process in which immune cells have an important function making the design and preparation of biomaterials with immunomodulatory functions an important new therapeutic strategy. 1,25-dihydroxyvitamin D3 (VD3) is crucial for bone metabolism and immune regulation. For post-defect bone regeneration, we developed a drug delivery system (DDS) based on chitosan (CS) and nanoparticles (NPs) to sustain the release effect of VD3 and desirable biological characteristics. The hydrogel system was physically characterized and confirmed to have good mechanical strength, degradation rate, and drug release rate. In vitro experiments showed that the cells had good biological activity when the hydrogel was co-cultured with MC3T3-E1 and RAW264.7. The high expression of ARG-1 and low expression of iNOS in macrophages confirmed that VD3-NPs/CS-GP hydrogel transformed lipopolysaccharide-induced M1 macrophages into M2 macrophages. Alkaline phosphatase and alizarin red staining showed that VD3-NPs/CS-GP hydrogel promoted osteogenic differentiation under inflammatory conditions. In conclusion, VD3-NPs/CS-GP hydrogel with synergistic anti-inflammatory and pro-osteogenic differentiation effects may serve as a potential immunomodulatory biomaterial for bone repair and regeneration in cases of bone defects.


Asunto(s)
Quitosano , Nanopartículas , Humanos , Hidrogeles/farmacología , Quitosano/farmacología , Osteogénesis , Regeneración Ósea , Materiales Biocompatibles/farmacología , Diferenciación Celular
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