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1.
Acta Pharm Sin B ; 14(2): 765-780, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38322349

ABSTRACT

A major challenge facing photodynamic therapy (PDT) is that the activity of the immune-induced infiltrating CD8+ T cells is subject to the regulatory T lymphocytes (Tregs), leaving the tumor at risk of recurrence and metastasis after the initial ablation. To augment the antitumor response and reprogram the immunosuppressive tumor microenvironment (TME), a supramolecular photodynamic nanoparticle (DACss) is constructed by the host-guest interaction between demethylcantharidin-conjugated ß-cyclodextrin (DMC-CD) and amantadine-terminated disulfide-conjugated FFVLGGGC peptide with chlorin e6 decoration (Ad-ss-pep-Ce6) to achieve intelligent delivery of photosensitizer and immunomodulator for breast cancer treatment. The acid-labile ß-carboxamide bond of DMC-CD is hydrolyzed in response to the acidic TME, resulting in the localized release of DMC and subsequent inhibition of Tregs. The guest molecule Ad-ss-pep-Ce6 can be cleaved by a high level of intracellular GSH, reducing photosensitizer toxicity and increasing photosensitizer retention in the tumor. With a significant increase in the CTL/Treg ratio, the combination of Ce6-based PDT and DMC-mediated immunomodulation adequately achieved spatiotemporal regulation and remodeling of the TME, as well as improved primary tumor and in situ lung metastasis suppression with the aid of PD-1 antibody.

2.
Biomater Adv ; 154: 213607, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37651963

ABSTRACT

Polyetheretherketone (PEEK) has emerged as a highly promising orthopedic implantation material due to its elastic modulus which is comparable to that of natural bone. This polymer exhibits impressive properties for bone implantation such as corrosion resistance, fatigue resistance, self-lubrication and chemical stability. Significantly, compared to metal-based implants, PEEK implants have mechanical properties that are closer to natural bone, which can mitigate the "stress shielding" effect in bone implantation. Nevertheless, PEEK is incapable of inducing osteogenesis due to its bio-inert molecular structure, thereby hindering the osseointegration process. To optimize the clinical application of PEEK, researchers have been working on promoting its bioactivity and endowing this polymer with beneficial properties, such as antibacterial, anti-inflammatory, anti-tumor, and angiogenesis-promoting capabilities. Considering the significant growth of research on PEEK implants over the past 5 years, this review aims to present a timely update on PEEK's modification methods. By highlighting the latest advancements in PEEK modification, we hope to provide guidance and inspiration for researchers in developing the next generation bone implants and optimizing their clinical applications.


Subject(s)
Polyethylene Glycols , Polymers , Polyethylene Glycols/chemistry , Polyethylene Glycols/pharmacology , Benzophenones , Ketones/therapeutic use , Ketones/chemistry , Ketones/pharmacology
3.
ACS Appl Mater Interfaces ; 15(22): 26863-26871, 2023 Jun 07.
Article in English | MEDLINE | ID: mdl-37230959

ABSTRACT

As the global energy crisis intensifies, the development of solar energy has become a vital area of focus for many nations. The utilization of phase change materials (PCMs) for photothermal energy storage in the medium temperature range holds great potential for various applications, but their conventional forms face several challenges. For instance, the longitudinal thermal conductivity of photothermal PCMs is inadequate for effective heat storage on the photothermal conversion surface, and there is a risk of leakage due to repeated solid-liquid phase transitions. Here, we report a solid-solid phase change material, tris(hydroxymethyl)aminomethane (TRIS), which has a phase change temperature of 132 °C in the medium temperature range, enabling high-grade and stable solar energy storage. To overcome the low thermal conductivity problem, we propose a large-scale production of oriented high thermal conductivity composites by compressing a mixture of TRIS and expanded graphite (EG) using the pressure induction method to create in-plane highly thermally conductive channels. Remarkably, the resulting phase change composites (PCCs) exhibit a directional thermal conductivity of 21.3 W/(m·K). Furthermore, the high phase change temperature (132 °C) and large phase change entropy (213.47 J/g) enable a large-capacity high-grade thermal energy to be used. The developed PCCs, when combined with selected photo-absorbers, exhibit efficient integration of solar-thermal conversion and storage. Additionally, we also demonstrated a solar-thermoelectric generator device with an energy output of 93.1 W/m2, which is close to the power of photovoltaic systems. Overall, this work provides a technological route to the large-scale fabrication of mid-temperature solar energy storage materials with high thermal conductivity, high phase change enthalpy, and no risk of leakage, and also offers a potential alternative to photovoltaic technology.

4.
Small ; 18(13): e2107987, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35122469

ABSTRACT

Recently, Li-ion capacitors (LICs) have drawn tremendous attention due to their high energy/power density along with long cycle life. Nevertheless, the slow kinetics and stability of the involved anodes as bottleneck barriers always result in the modest properties of devices. The exploration of advanced anodes with both high ionic and electronic conductivities as well as structural stability thus becomes more significant for practical applications of LICs. Herein, a single-crystal nano-subunits assembled hierarchical accordion-shape WNb2 O8 micro-/nano framework is first designed via a one-step scalable strategy with the multi-layered Nb2 CTx as a precursor. The underlying solid solution Li-storage mechanism of the WNb2 O8 just with a volumetric expansion of ≈1.5% is proposed with in situ analysis. Benefiting from congenitally crystallographic merits, single-crystalline characteristic, and open accordion-like architecture, the resultant WNb2 O8 as a robust anode platform is endowed with fast electron/ion transport capability and multi-electron redox contributions from W/Nb, and accordingly, delivers a reversible capacity of ≈135.5 mAh g-1 at a high rate of 2.0 A g-1 . The WNb2 O8 assembled LICs exhibit an energy density of ≈33.0 Wh kg-1 at 9 kW kg-1 , coupled with remarkable electrochemical stability. The work provides meaningful insights into the rational design and construction of advanced bimetallic niobium oxides for next-generation LICs.

5.
Micromachines (Basel) ; 12(2)2021 Feb 08.
Article in English | MEDLINE | ID: mdl-33567494

ABSTRACT

Optical interferometry plays an important role in the topographical surface measurement and characterization in precision/ultra-precision manufacturing. An appropriate surface reconstruction algorithm is essential in obtaining accurate topography information from the digitized interferograms. However, the performance of a surface reconstruction algorithm in interferometric measurements is influenced by environmental disturbances and system noise. This paper presents a comparative analysis of three algorithms commonly used for coherence envelope detection in vertical scanning interferometry, including the centroid method, fast Fourier transform (FFT), and Hilbert transform (HT). Numerical analysis and experimental studies were carried out to evaluate the performance of different envelope detection algorithms in terms of measurement accuracy, speed, and noise resistance. Step height standards were measured using a developed interferometer and the step profiles were reconstructed by different algorithms. The results show that the centroid method has a higher measurement speed than the FFT and HT methods, but it can only provide acceptable measurement accuracy at a low noise level. The FFT and HT methods outperform the centroid method in terms of noise immunity and measurement accuracy. Even if the FFT and HT methods provide similar measurement accuracy, the HT method has a superior measurement speed compared to the FFT method.

6.
Nanoscale ; 12(6): 4119-4127, 2020 Feb 14.
Article in English | MEDLINE | ID: mdl-32022075

ABSTRACT

Recently, there has been an urgent need for flexible and low cost rechargeable batteries for the emerging flexible and wearable electronic devices. Herein, MnS nanoparticles embedded in carbon nanowires/reduced graphene oxide (MnS@CNWs/rGO) composite paper were synthesized via a simple yet scalable strategy with Mn based coordination nanowires and graphene oxide as precursors. The combination of multi-dimensional subunits offers not only a robust structure but also abundant pathways for fast electron/ion diffusion. When directly used as a free-standing electrode for sodium ion batteries (SIBs), the ultra-flexible paper anode exhibits excellent mechanical and electrochemical performance, benefitting from the synergistic effects between nano-dimensional MnS encapsulated in CNWs and conductive rGO nanosheets. Remarkably, a high reversible gravimetric/volumetric capacity of ∼560 mA h g-1/∼362.3 mA h cm-3 is obtained using the self-supported flexible electrode at a current density of 0.1 A g-1, which is almost 92.4% of the theoretical capacity of MnS. More competitively, the flexible MnS@CNWs/rGO anode exhibits an unprecedented long cycle life with a high reversible capacity of ∼150 mA h g-1 at 1 A g-1 after 10, 000 cycles. This highly favours the promising application of MnS@CNWs/rGO paper in advanced flexible SIBs as an appealing anode.

7.
Mar Pollut Bull ; 145: 153-160, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31590772

ABSTRACT

As a global pollutant, microplastics have attracted attention from the public and researchers. However, the lack of standard and time-saving methods for analysis has become one of the bottlenecks in microplastics research. Here, we demonstrate TGA coupled to FTIR to identify and quantify certain microplastics in environment. Samples were pyrolyzed in TGA and the pyrolysis gases were analyzed by FTIR. Combining TGA and FTIR data adds discriminatory power as temperature profiles and absorption spectra differ among several common plastics. To quantify on a mass basis, we calibrated on characteristic IR peaks at temperatures of maximum weight loss for individual polymers. The method can distinguish PVC, PS and was validated by spiking samples with known quantities of microplastics. The result of field sample experiments showed that TGA-FTIR can be used to identify and quantify PVC and PS in bivalves, seawater and soil. And the method may be applicable to environmental samples.


Subject(s)
Plastics/analysis , Spectroscopy, Fourier Transform Infrared/methods , Thermogravimetry/methods , Water Pollutants, Chemical/analysis , Animals , Bivalvia/chemistry , China , Environmental Monitoring/methods , Plastics/chemistry , Polymers/analysis , Polymers/chemistry , Reproducibility of Results , Seawater/chemistry , Soil Pollutants/analysis , Soil Pollutants/chemistry , Water Pollutants, Chemical/chemistry
8.
Materials (Basel) ; 12(17)2019 Aug 28.
Article in English | MEDLINE | ID: mdl-31466365

ABSTRACT

In this work, SiC and Cu particles were utilized to enhance the thermal and mechanical properties of Al matrix composites. The ball-milling and cold-compact methods were applied to prepare Al matrix composites, and the uniform distribution of SiC and Cu particles in the composite confirms the validity of our preparation method. After characterizing the thermal conductivity and the compressibility of the prepared composites, results show that small particles have a higher potential to improve compressibility than large particles, which is attributed to the size effect of elastic modulus. The addition of SiC to the Al matrix will improve the compressibility behavior of Al matrix composites, and the compressibility can be enhanced by 100% when SiC content is increased from 0 to 30%. However, the addition of SiC particles has a negative effect on thermal conductivity because of the low thermal conductivity of SiC particles. The addition of Cu particles to Al-SiC MMCs could further slightly improve the compressibility behavior of Al-SiC/Cu MMCs, while the thermal conductivity could be enhanced by about 100% when the Cu content was increased from 0 to 30%. To meet the need for low density and high thermal conductivity in applications, it is more desirable to enhance the specific thermal conductivity by enlarging the preparation pressure and/or sintering temperature. This work is expected to supply some information for preparing Al matrix composites with low density but high thermal conductivity and high compressibility.

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