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1.
EBioMedicine ; 106: 105243, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39004066

RESUMEN

BACKGROUND: Surgery is crucial for glioma treatment, but achieving complete tumour removal remains challenging. We evaluated the effectiveness of a probe targeting monocarboxylate transporter 4 (MCT4) in recognising gliomas, and of near-infrared window II (NIR-II) fluorescent molecular imaging and photothermal therapy as treatment strategies. METHODS: We combined an MCT4-specific monoclonal antibody with indocyanine green to create the probe. An orthotopic mouse model and a transwell model were used to evaluate its ability to guide tumour resection using NIR-II fluorescence and to penetrate the blood-brain barrier (BBB), respectively. A subcutaneous tumour model was established to confirm photothermal therapy efficacy. Probe specificity was assessed in brain tissue from mice and humans. Finally, probe effectiveness in photothermal therapy was investigated. FINDINGS: MCT4 was differentially expressed in tumour and normal brain tissue. The designed probe exhibited precise tumour targeting. Tumour imaging was precise, with a signal-to-background (SBR) ratio of 2.8. Residual tumour cells were absent from brain tissue postoperatively (SBR: 6.3). The probe exhibited robust penetration of the BBB. Moreover, the probe increased the tumour temperature to 50 °C within 5 min of laser excitation. Photothermal therapy significantly reduced tumour volume and extended survival time in mice without damage to vital organs. INTERPRETATION: These findings highlight the potential efficacy of our probe for fluorescence-guided surgery and therapeutic interventions. FUNDING: Jilin Province Department of Science and Technology (20200403079SF), Department of Finance (2021SCZ06) and Development and Reform Commission (20200601002JC); National Natural Science Foundation of China (92059207, 92359301, 62027901, 81930053, 81227901, U21A20386); and CAS Youth Interdisciplinary Team (JCTD-2021-08).

2.
Adv Mater ; : e2405877, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38889909

RESUMEN

Targeted imaging of cancer lymphatic metastasis remains challenging due to its highly heterogeneous molecular and phenotypic diversity. Herein, triple-targeted protein nanoprobes capable of specifically binding to three targets for imaging cancer lymphatic metastasis, through a data-driven design approach combined with a synthetic biology-based assembly strategy, are introduced. Specifically, to address the diversity of metastatic lymph nodes (LNs), a combination of three targets, including C-X-C motif chemokine receptor 4 (CXCR4), transferrin receptor protein 1 (TfR1), and vascular endothelial growth factor receptor 3 (VEGFR3) is identified, leveraging machine leaning-based bioinformatics analysis and examination of LN tissues from patients with gastric cancer. Using this identified target combination, ferritin nanocage-based nanoprobes capable of specifically binding to all three targets are designed through the self-assembly of genetically engineered ferritin subunits using a synthetic biology approach. Using these nanoprobes, multiplexed imaging of heterogeneous metastatic LNs is successfully achieved in a polyclonal lymphatic metastasis animal model. In 19 freshly resected human gastric specimens, the signal from the triple-targeted nanoprobes significantly differentiates metastatic LNs from benign LNs. This study not only provides an effective nanoprobe for imaging highly heterogeneous lymphatic metastasis but also proposes a potential strategy for guiding the design of targeted nanomedicines for cancer lymphatic metastasis.

3.
Langmuir ; 40(22): 11745-11756, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38768262

RESUMEN

Interfacial solar desalination is a method for desalinating seawater using solar energy, and the long-term use of this technology requires a stable evaporation rate and some ability to prevent salt crystallization. To address these issues, carbonized polydopamine-coated bentonite (C@PBT), poly(vinyl alcohol), and cellulose nanofibers were used to construct a three-dimensional oriented hydrogel evaporator with a multilayered honeycomb porous structure for long-term desalination. Carbon nanoparticles transferred between the layers of the bentonite, which increases the spacing of the layers and confers a more effective solar light trapping ability. The evaporation rate was 2.26 kg m-2 h-1 in 20 wt % NaCl solution, and no salt crystals were precipitated from the surface of the evaporator in 12 h of continuous operation. This phenomenon occurs due to the wide distribution of pore sizes and the large size of the pores within the evaporator, which create ample space for salt ions to move freely. Furthermore, after undergoing 300 cycles of compression, its internal pore structure remains intact, and the rate of evaporation remains stable. It ensures the evaporator stability during outdoor cycles. The research work provides an effective method to solve the salt accumulation problem and shows its great potential for application.

4.
Eur J Nucl Med Mol Imaging ; 51(9): 2569-2582, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38647671

RESUMEN

PURPOSE: One of the main reasons for prostate cancer (PCa) recurrence is the difficulty in identifying and removing cancerous lesions during surgery. Accurately localizing and excising cancerous tissue remains a significant challenge. The second near-infrared window (NIR-II, 1000-1700 nm) fluorescence offers enhanced resolution, a high signal-to-noise ratio, and the potential for deeper tissue penetration. However, this technology is not currently employed for intraoperative imaging of PCa. This study aims to construct a new NIR-II probe targeting B7-H3 (AbB7-H3-800CW) for accurate intraoperative identification and resection of PCa. METHODS: Based on the differential expression of B7-H3 in PCa, we designed a novel imaging probe to accurately identify and guide the resection of preclinical PCa models and ex vivo human PCa tissues using NIR-II fluorescence imaging technology. RESULTS: Analyzing tissue samples from 60 clinical cases of PCa, along with benign prostatic hyperplasia and normal prostate tissue from 22 cases, we observed a significant difference in B7-H3 protein expression levels (P < 0.001). Subcutaneous and orthotopic mouse models of PCa were imaged using NIR-II fluorescence after AbB7-H3-800CW injection, showing promising results with successful tumor targeting and high-contrast images achieved within 24-48 h post-injection. The imaging also enabled the detection of occult PCa lesions approximately 1 mm in diameter. In addition, imaging analysis of human PCa and adjacent tissues using AbB7-H3-800CW incubation revealed that cancer tissues exhibited a significantly higher fluorescence intensity than adjacent tissues (P < 0.05), which was conducive to the evaluation of tumor resection margin in vitro. CONCLUSION: The findings revealed that B7-H3 was a compelling imaging target for PCa. The AbB7-H3-800CW molecular imaging probe is capable of accurately identifying PCa lesions and guiding their removal. This approach can potentially reduce the rate of surgical margins under NIR-II fluorescence guidance.


Asunto(s)
Antígenos B7 , Neoplasias de la Próstata , Masculino , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/metabolismo , Antígenos B7/metabolismo , Humanos , Ratones , Animales , Imagen Molecular/métodos , Línea Celular Tumoral , Rayos Infrarrojos , Imagen Óptica/métodos , Cirugía Asistida por Computador/métodos , Resultado del Tratamiento
5.
Carbohydr Polym ; 333: 121951, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38494216

RESUMEN

Passive daytime radiative cooling (PDRC) as a zero-energy-consumption cooling technique offers rich opportunities in reducing global energy consumption and mitigating CO2 emissions. Developing high-performance PDRC coolers with practical applicability based on sustainable materials is of great significance, but remains a big challenge. Herein, polyvinyl alcohol (PVA) and esterified cellulose (EC) extracted from sawdust were used as raw materials to construct foams by using a dual-crosslinking assisted-unidirectional freeze-drying strategy followed by hydrophobic surface modification. The resultant PVA/EC (PEC) foams with ideal hierarchical macropore structure displayed various excellent features, such as low thermal conductivity (26.2 mW·m-1·K-1), high solar reflectance (95 %) and infrared emissivity (0.97), superhydrophobicity as well as high mechanical properties. The features allowed the PEC foams to be used as radiative coolers with excellent PDRC performance and thermal insulating materials. A maximum sub-ambient temperature drops of 10.2 °C could be achieved for optimal PEC foams. Building simulations indicated that PEC foams could save 55.8 % of the energy consumption for Xi'an. Our work would give inspiration for designing various types of PDRC coolers, including but certainly not limited to foams-based radiative coolers.

6.
ACS Appl Mater Interfaces ; 16(8): 11134-11144, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38354312

RESUMEN

Recently, materials with superlubricity captured widespread attention on account of their great potential in energy savings and environmental protection. However, certain issues still remain to be solved for the traditional materials, such as the dependence on strict conditions and an unstable superlubricity state. Herein, a long-term stable superlubricity coating was prepared using a low-cost and simple method via an epoxy-based coating with polydimethylsiloxane (PDMS) brushes under silicone oil (SO) lubrication conditions. Compared with the pure epoxy resin matrix, the friction coefficient and wear track width of the superlubricity coating with the optimal amount of 6 wt % PDMS are reduced to 0.006 and 50.9 µm (reduced by 10-fold and 5.6-fold decrease, respectively). In addition, the coating can maintain a stable superlubricity state during a 5 h tribological test. The superlubricity of the coating results from the synergistic lubrication effect of the PDMS brush and SO. First, PDMS brushes with high-stretched conformation due to the swelling effect of the SO can significantly reduce friction. Second, a stable oil film is generated between the contact surfaces, which significantly improves the frictional performance. Moreover, the PDMS incorporated into the coating matrix, along with oil-swelling PDMS brushes on the surface, is highly beneficial for enhancing corrosion resistance of the epoxy resin matrix. Such an epoxy-based coating with long-term stable superlubricity is considered as a potential lubricating and protective surface for tribological components for long-term service.

7.
ACS Nano ; 18(3): 2395-2408, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38194614

RESUMEN

The development of high-energy-density Li-S batteries (LSBs) is still hindered by the disturbing polysulfide shuttle effect. Herein, with clever combination between "high entropy" and MXene, an HE-MXene doped graphene composite containing multiple element quasi-atoms as bifunctional mediator for separator modification (HE-MXene/G@PP) in LSBs is proposed. The HE-MXene/G@PP offers high electrical conductivity for fast lithium polysulfide (LiPS) redox conversion kinetics, abundant metal active sites for efficient chemisorption with LiPSs, and strong lipophilic characteristics for uniform Li+ deposition on lithium metal surface. As demonstrated by DFT theoretical calculations, in situ Raman, and DRT results successively, HE-MXene/G@PP efficiently captures LiPSs through synergistic modulation of the cocktail effect and accelerates the LiPSs redox reaction, and the lattice distortion effect effectively induces the homogeneous deposition of dendritic-free lithium. Therefore, this work achieves excellent long-term cycling performance with a decay rate of 0.026%/0.031% per cycle after 1200 cycles at 1 C/2 C. The Li||Li symmetric cell still maintains a stable overpotential after 6000 h under 40 mA cm-2/40 mAh cm-2. Furthermore, it delivers favorable cycling stability under 7.8 mg cm-2 and a low E/S ratio of 5.6 µL mg-1. This strategy provides a rational approach to resolve the sulfur cathode and lithium anode problems simultaneously.

8.
Eur J Nucl Med Mol Imaging ; 51(5): 1233-1245, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38095676

RESUMEN

PURPOSE: Uncontrolled intra-alveolar inflammation is a central pathogenic feature, and its severity translates into a valid prognostic indicator of acute lung injury (ALI). Unfortunately, current clinical imaging approaches are unsuitable for visualizing and quantifying intra-alveolar inflammation. This study aimed to construct a small-sized vascular cell adhesion molecule-1 (VCAM-1)-targeted magnetic particle imaging (MPI) nanoprobe (ESPVPN) to visualize and accurately quantify intra-alveolar inflammation at the molecular level. METHODS: ESPVPN was engineered by conjugating a peptide (VHPKQHRGGSK(Cy7)GC) onto a polydopamine-functionalized superparamagnetic iron oxide core. The MPI performance, targeting, and biosafety of the ESPVPN were characterized. VCAM-1 expression in HUVECs and mouse models was evaluated by western blot. The degree of inflammation and distribution of VCAM-1 in the lungs were assessed using histopathology. The expression of pro-inflammatory markers and VCAM-1 in lung tissue lysates was measured using ELISA. After intravenous administration of ESPVPN, MPI and CT imaging were used to analyze the distribution of ESPVPN in the lungs of the LPS-induced ALI models. RESULTS: The small-sized (~10 nm) ESPVPN exhibited superior MPI performance compared to commercial MagImaging® and Vivotrax, and ESPVPN had effective targeting and biosafety. VCAM-1 was highly expressed in LPS-induced ALI mice. VCAM-1 expression was positively correlated with the LPS-induced dose (R = 0.9381). The in vivo MPI signal showed positive correlations with both VCAM-1 expression (R = 0.9186) and representative pro-inflammatory markers (MPO, TNF-α, IL-6, IL-8, and IL-1ß, R > 0.7). CONCLUSION: ESPVPN effectively targeted inflammatory lungs and combined the advantages of MPI quantitative imaging to visualize and evaluate the degree of ALI inflammation.


Asunto(s)
Lesión Pulmonar Aguda , Neumonía , Ratones , Animales , Molécula 1 de Adhesión Celular Vascular/efectos adversos , Molécula 1 de Adhesión Celular Vascular/metabolismo , Lipopolisacáridos/farmacología , Lesión Pulmonar Aguda/diagnóstico por imagen , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/metabolismo , Pulmón/diagnóstico por imagen , Pulmón/patología , Inflamación/inducido químicamente , Neumonía/diagnóstico por imagen , Neumonía/metabolismo , Fenómenos Magnéticos
9.
Adv Mater ; 36(9): e2307967, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37910074

RESUMEN

The rapid charge recombination, low selectivity for two-electron oxygen reduction reaction (ORR), and limited O2 diffusion rate hinder the practical applications of photocatalytic H2 O2 generation. Herein, a triphase photocatalytic system in which the H2 O2 generation occurs at the air-liquid-solid joint interfaces is developed, using polymeric carbon nitride (PCN). The introduction of pyrrole units and cyano group into PCN can promote the activation of oxygen molecules and facilitate the spatial separation of HOMO and LUMO orbits, hence improving the charge carrier separation efficiency and enhancing the formation of H2 O2 . Importantly, the gas-liquid-solid triphase interface system allows for the rapid transport of oxygen from the air to the reaction interface, overcoming the low solubility and slow diffusion of oxygen in the water in conventional liquid reaction systems. The triphase system shows a benchmark H2 O2 generation rate over PCN-based materials in pure water (2063.21 µmol g-1 h-1 ), which is an approximate tenfold enhancement as compared to powder photocatalyst (215.44 µmol g-1 h-1 ). Simulation and electrochemical tests reveal that the rapid oxygen diffusion rate of triphase interface can promote charge separation and provide more O2 to generate H2 O2 . This work provides a promising strategy for constructing an efficient and sustainable H2 O2 production system.

10.
ACS Appl Mater Interfaces ; 16(1): 1451-1460, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38112199

RESUMEN

Hydrogels with excellent mechanical flexibility are widely used in flexible electronic devices. However, it is difficult to meet further applications of high-power integrated flexible electronics as a result of their low thermal conductivity. Herein, highly thermally conductive composite hydrogels with a solid-liquid interpenetrating thermal conductivity network are constructed by aromatic polyamide nanofibers (ANF) and fluorinated graphene (FG) reinforced poly(vinyl alcohol) (PVA) and cross-linked by tannic acid (TA) solution immersion to obtain a hydrogel with a double cross-linked network. The PVA-ANF-FG3T-11.1% composite hydrogel exhibits good mechanical properties compared to PVA-ANFT, with a tensile modulus of up to 0.89 MPa, a tensile strength of up to 1.23 MPa, and an energy of rupture of up to 3.45 MJ cm-3, which is mainly attributed to the multihydrogen bonding interactions in the composite hydrogel. In addition, the friction coefficient of the PVA-ANF-FG3T-11.1% composite hydrogel is 0.178, making it suitable for use in high-friction coefficient applications. The thermal conductivity of the PVA-ANF-FG3T-11.1% composite hydrogel is 1.42 W m-1 K-1, which is attributed to the synergistic effect of the solid thermal conductivity network and the liquid convection network, resulting in a high thermal conductivity of the composite hydrogel. The high thermal conductivity of the PVA-ANF-FG3T-11.1% composite hydrogel shows great potential for flexible wearable electronics and cooling paste applications.

11.
ACS Appl Mater Interfaces ; 16(1): 1794-1804, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38117240

RESUMEN

Salt deposition and pollutant enrichment greatly hamper efficient and sustainable water production for a solar evaporator. Inspired by the desert beetle, a dual-region hydrophobic graphene/hydrophilic titanium dioxide (TiO2) aerogel (GTA) with internal hydrophilic-hydrophobic hybrid wettability structure is prepared via a facile freeze-drying and thermal reduction method. The evaporator shows adjustable wettability, optimized water content, and a low energy loss in the evaporation process. Simultaneously, the hybrid wetting structure in aerogel subjects salt to a dynamic crystallization-dissolution process to prevent salt deposition. The GTA solar evaporator achieves an evaporation rate of 1.52 kg·m-2·h-1 with a 91.02% efficiency under 1 sun irradiation. Furthermore, GTAs achieve a stable evaporation rate in high salinity brine (25 wt % NaCl) under 1 sun irradiation for 100 h, which could compete well with other most advanced photothermal evaporation materials. Moreover, the synergistic effect of graphene and TiO2 endows GTAs with excellent photocatalytic degradation and self-cleaning properties, which can effectively reduce the enrichment of contaminants on the evaporator. Therefore, GTA evaporators can efficiently and stably obtain clean water from seawater and wastewater, which provides a feasible strategy for the purification of complex wastewater.

12.
EBioMedicine ; 98: 104880, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38035463

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is the sixth most common malignancy globally and ranks third in terms of both mortality and incidence rates. Surgical resection holds potential as a curative approach for HCC. However, the residual disease contributes to a high 5-year recurrence rate of 70%. Due to their excellent specificity and optical properties, fluorescence-targeted probes are deemed effective auxiliary tools for addressing residual lesions, enabling precise surgical diagnosis and treatment. Research indicates histone deacetylase 6 (HDAC6) overexpression in HCC cells, making it a potential imaging biomarker. This study designed a targeted small-molecule fluorescent probe, SeCF3-IRDye800cw (SeCF3-IRD800), operating within the Second near-infrared window (NIR-II, 1000-1700 nm). The study confirms the biocompatibility of SeCF3-IRD800 and proceeds to demonstrate its applications in imaging in vivo, fluorescence-guided surgery (FGS) for liver cancer, liver fibrosis imaging, and clinical samples incubation, thereby preliminarily validating its utility in liver cancer. METHODS: SeCF3-IRD800 was synthesized by combining the near-infrared fluorescent dye IRDye800cw-NHS with an improved HDAC6 inhibitor. Initially, a HepG2-Luc subcutaneous tumor model (n = 12) was constructed to investigate the metabolic differences between SeCF3-IRD800 and ICG in vivo. Subsequently, HepG2-Luc (n = 12) and HCCLM3-Luc (n = 6) subcutaneous xenograft mouse models were used to assess in vivo targeting by SeCF3-IRD800. The HepG2-Luc orthotopic liver cancer model (n = 6) was employed to showcase the application of SeCF3-IRD800 in FGS. Liver fibrosis (n = 6) and HepG2-Luc orthotopic (n = 6) model imaging results were used to evaluate the impact of different pathological backgrounds on SeCF3-IRD800 imaging. Three groups of fresh HCC and normal liver samples from patients with liver cancer were utilized for SeCF3-IRD800 incubation ex vivo, while preclinical experiments illustrated its potential for clinical application. FINDINGS: The HDAC6 inhibitor 6 (SeCF3) modified with trifluoromethyl was labeled with IRDy800CW-NHS to synthesize the small-molecule targeted probe SeCF3-IRD800, with NIR-II fluorescence signals. SeCF3-IRD800 was rapidly metabolized by the kidneys and exhibited excellent biocompatibility. In vivo validation demonstrated that SeCF3-IRD800 achieved optimal imaging within 8 h, displaying high tumor fluorescence intensity (7658.41 ± 933.34) and high tumor-to-background ratio (5.20 ± 1.04). Imaging experiments with various expression levels revealed its capacity for HDAC6-specific targeting across multiple HCC tumor models, suitable for NIR-II intraoperative imaging. Fluorescence-guided surgery experiments were found feasible and capable of detecting sub-visible 2 mm tumor lesions under white light, aiding surgical decision-making. Further imaging of liver fibrosis mice showed that SeCF3-IRD800's imaging efficacy remained unaffected by liver pathological conditions. Correlations were observed between HDAC6 expression levels and corresponding fluorescence intensity (R2 = 0.8124) among normal liver, liver fibrosis, and HCC tissues. SeCF3-IRD800 identified HDAC6-positive samples from patients with HCC, holding advantages for perspective intraoperative identification in liver cancer. Thus, the rapidly metabolized HDAC6-targeted small-molecule NIR-II fluorescence probe SeCF3-IRD800 holds significant clinical translational value. INTERPRETATION: The successful application of NIR-II fluorescence-guided surgery in liver cancer indicates that SeCF3-IRD800 has great potential to improve the clinical diagnosis and treatment of liver cancer, and could be used as an auxiliary tool for surgical treatment of liver cancer without being affected by liver pathology. FUNDING: This paper is supported by the National Natural Science Foundation of China (NSFC) (92,059,207, 62,027,901, 81,930,053, 81,227,901, 82,272,105, U21A20386 and 81,971,773), CAS Youth Interdisciplinary Team (JCTD-2021-08), the Zhuhai High-level Health Personnel Team Project (Zhuhai HLHPTP201703), and Guangdong Basic and Applied Basic Research Foundation under Grant No. 2022A1515011244.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Humanos , Ratones , Línea Celular Tumoral , Colorantes Fluorescentes , Histona Desacetilasa 6 , Cirrosis Hepática , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Sondas Moleculares
13.
ACS Appl Mater Interfaces ; 15(22): 27223-27233, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37218624

RESUMEN

With the rapid development of miniaturization and high-power portable electronics, the accumulation of undesired heat can degrade the performance of electronic devices and even cause fires. Therefore, multifunctional thermal interface materials that combine high thermal conductivity and flame retardancy remain a challenge. Herein, an ILC (ionic liquids crystal)-armored boron nitride nanosheet (BNNS) with flame retardant functional groups was first developed. The high in-plane orientation structure aerogel film made of such an ILC-armored BNNS and aramid nanofiber and polyvinyl alcohol matrix through directional freeze-drying and mechanical pressing exhibits strong anisotropy thermal conductivity (λ// of 17.7 W m-1 K-1 and λ⊥ of 0.98 W m-1 K-1). In addition, the highly oriented IBAP aerogel films have excellent flame retardancy (peak heat release rate = 44.5 kW/m2 and heat release rate = 0.8 MJ/m2) due to the physical barrier effect and catalytic carbonization effect of ILC-armored BNNS. Meanwhile, IBAP aerogel films exhibit good flexibility and mechanical properties, even in harsh environments such as acids and bases. Further, IBAP aerogel films can also be used as a substrate for paraffin phase change composites. The ILC-armored BNNS provides a practical way to produce flame-resistant polymer composites with high thermal conductivity for TIMs in modern electronic devices.

14.
Langmuir ; 39(10): 3589-3600, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36848873

RESUMEN

Nitrogen-doped lubricating additives have been proved to be an effective strategy to improve the tribological properties of lubricating oil. However, the traditional preparation methods of nitrogen-doped lubricating additives have the defects including harsh preparation conditions and a time-consuming preparation process. Herein, we report a preparation method of nitrogen-doped carbon dot (NCD) lubricating additives in a short time by one-step aldehyde condensation reaction at room temperature. The small size effect and nitrogen-containing functional groups of NCD lubricating additives provide favorable conditions for their dispersion and low friction in base oil. The tribological properties of NCD lubricating additives in sunflower oil (SFO) and PAO10 were systematically evaluated. The results show that NCD lubricating additives could reduce the average friction coefficient of SFO from 0.15 to 0.06 and PAO10 oil from 0.12 to 0.06, and the wear width is also decreased by 50-60%. In particular, the friction curve is very stable, and the friction coefficient was maintained at about 0.06 even under the working time of 5 h. By analyzing the morphology and chemical properties of the worn surface, the lubrication effect of NCDs is attributed to its small size effect and adsorption, which was easy to enter the friction gap to fill and repair. Furthermore, the doping of nitrogen induces the occurrence of friction chemical reactions, forming a friction film of nitrides and metal oxides at the friction interface, which effectively reduces the friction and wear of the surface. These findings provide a possibility for the convenient and effective preparation of NCD lubricating additives.

15.
ACS Appl Mater Interfaces ; 15(8): 11053-11061, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36791287

RESUMEN

Recently, smart windows have attracted widespread attention on account of their unique features, yet traditional smart windows still rely on external energy support to accomplish dynamic reversible switching, which not only confines usage but also causes waste of energy. For this purpose, we have prepared hemiaminal dynamic covalent network (HDCN) film with outstanding flexibility and strength by a simple and low-cost method, in which the modulus is 206.28 MPa and the elongation at break is 39.02%. Additionally, the transition from a transparent to an opaque state is achieved when the film is stimulated by humidity, and the dynamic transformation of the film to different phases of transparency is obtained when the film is exposed to different relative humidities (60-99%). Most importantly, HDCN film fulfills the modern green requirements and enables complete dissolution in a certain mildly acidic solution, avoiding environmental pollution when the material is discarded due to loss of function. The dynamic tunability of HDCN film demonstrates great advantages and potential in smart windows and anticounterfeiting.

16.
EBioMedicine ; 89: 104476, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36801616

RESUMEN

BACKGROUND: Surgery is the cornerstone of colorectal cancer (CRC) treatment, yet complete removal of the tumour remains a challenge. The second near-infrared window (NIR-II, 1000-1700 nm) fluorescent molecular imaging is a novel technique, which has broad application prospects in tumour surgical navigation. We aimed to evaluate the ability of CEACAM5-targeted probe for CRC recognition and the value of NIR-II imaging-guided CRC resection. METHODS: We constructed the probe 2D5-IRDye800CW by conjugated anti-CEACAM5 nanobody (2D5) with near-infrared fluorescent dye IRDye800CW. The performance and benefits of 2D5-IRDye800CW at NIR-II were confirmed by imaging experiments in mouse vascular and capillary phantom. Then mouse colorectal cancer subcutaneous tumour model (n = 15), orthotopic model (n = 15), and peritoneal metastasis model (n = 10) were constructed to investigate biodistribution of probe and imaging differences between NIR-I and NIR-II in vivo, and then tumour resection was guided by NIR-II fluorescence. Fresh human colorectal cancer specimens were incubated with 2D5-IRDye800CW to verify its specific targeting ability. FINDINGS: 2D5-IRDye800CW had an NIR-II fluorescence signal extending to 1600 nm and bound specifically to CEACAM5 with an affinity of 2.29 nM. In vivo imaging, 2D5-IRDye800CW accumulated rapidly in tumour (15 min) and could specifically identify orthotopic colorectal cancer and peritoneal metastases. All tumours were resected under NIR-II fluorescence guidance, even smaller than 2 mm tumours were detected, and NIR-II had a higher tumour-to-background ratio than NIR-I (2.55 ± 0.38, 1.94 ± 0.20, respectively). 2D5-IRDye800CW could precisely identify CEACAM5-positive human colorectal cancer tissue. INTERPRETATION: 2D5-IRDye800CW combined with NIR-II fluorescence has translational potential as an aid to improve R0 surgery of colorectal cancer. FUNDINGS: This study was supported by Beijing Natural Science Foundation (JQ19027), the National Key Research and Development Program of China (2017YFA0205200), National Natural Science Foundation of China (NSFC) (61971442, 62027901, 81930053, 92059207, 81227901, 82102236), Beijing Natural Science Foundation (L222054), CAS Youth Interdisciplinary Team (JCTD-2021-08), the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA16021200), the Zhuhai High-level Health Personnel Team Project (Zhuhai HLHPTP201703), the Fundamental Research Funds for the Central Universities (JKF-YG-22-B005) and Capital Clinical Characteristic Application Research (Z181100001718178). The authors would like to acknowledge the instrumental and technical support of the multi-modal biomedical imaging experimental platform, Institute of Automation, Chinese Academy of Sciences.


Asunto(s)
Neoplasias Colorrectales , Imagen Óptica , Humanos , Animales , Ratones , Adolescente , Distribución Tisular , Imagen Óptica/métodos , Antígeno Carcinoembrionario , Proteínas Ligadas a GPI , Neoplasias Colorrectales/patología
17.
Arch Gerontol Geriatr ; 103: 104797, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36058044

RESUMEN

Objective Most previous studies focusing on the association between depressive symptoms and lung function were conducted in patients with chronic lung diseases. This study aims to investigate the association of depressive symptoms with lung function among general Chinese middle-aged and older adults. Participants This study used data from the China Health and Retirement Longitudinal Study (CHARLS). Analyses were conducted with data from three waves (2011, 2013, and 2015) and restricted to those respondents aged 45 and older. Finally, 9487 individuals [mean age (SD) = 58.47 (9.19); female, 53.1%] were included in analysis. Methods Depressive symptoms were measured by the Chinese version of 10-item Center for Epidemiological Studies Depression Scale (CESD-10). Lung function was assessed by peak expiratory flow (PEF). Two-level linear mixed growth models were used to evaluate the longitudinal association between depressive symptoms and PEF. Results Depressive symptoms were significantly associated with PEF among general middle-aged and older adults (b = -1.85, p < 0.001) after adjusting for multiple confounding factors. A significant interaction between depressive symptoms and gender was found (b = 1.29, p < 0.001). The association between depressive symptoms and PEF was greater for men (b = -2.36, p < 0.001) than for women (b = -1.46, p < 0.001). Conclusions This longitudinal study found that increased depressive symptoms were associated with reduced PEF in middle-aged and older adults in China. Compared with women, men with a higher level of depressive symptoms experienced a greater decrement in PEF. Our findings suggest that it is possible to reduce the effects of PEF by improving psychological health among general middle-aged and older populations.

18.
ACS Nano ; 16(10): 17049-17061, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36173441

RESUMEN

Three-dimensional (3D) elastic aerogels enable diverse applications but are usually restricted by their low thermal and electrical transfer efficiency. Here, we demonstrate a strategy for fabricating the highly thermally and electrically conductive aerogels using hybrid carbon/ceramic structural units made of hexagonal boron nitride nanoribbons (BNNRs) with in situ-grown orthogonally structured graphene (OSG). High-aspect-ratio BNNRs are first interconnected into a 3D elastic and thermally conductive skeleton, in which the horizontal graphene layers of OSG provide additional hyperchannels for electron and phonon conduction, and the vertical graphene sheets of OSG greatly improve surface roughness and charge polarization ability of the entire skeleton. The resulting OSG/BNNR hybrid aerogel exhibits very high thermal and electrical conductivity (up to 7.84 W m-1 K-1 and 340 S m-1, respectively) at a low density of 45.8 mg cm-3, which should prove to be vastly advantageous as compared to the reported carbonic and/or ceramic aerogels. Moreover, the hybrid aerogel possesses integrated properties of wide temperature-invariant superelasticity (from -196 to 600 °C), low-voltage-driven Joule heating (up to 42-134 °C at 1-4 V), strong hydrophobicity (contact angel of up to 156.1°), and powerful broadband electromagnetic interference (EMI) shielding effectiveness (reaching 70.9 dB at 2 mm thickness), all of which can maintain very well under repeated mechanical deformations and long-term immersion in strong acid or alkali solution. Using these extraordinary comprehensive properties, we prove the great potential of OSG/BNNR hybrid aerogel in wearable electronics for regulating body temperature, proofing water and pollution, removing ice, and protecting human health against EMI.

19.
Biosensors (Basel) ; 12(9)2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36140088

RESUMEN

The cancer stem cells (CSC) are the roots of cancer. The CSC hypothesis may provide a model to explain the tumor cell heterogeneity. Understand the biological mechanism of CSC will help the early detection and cure of cancer. The discovery of the dynamic changes in CSC will be possible by the using of bio-engineering techniques-lineage tracing. However, it is difficult to obtain real-time, continuous, and dynamic live-imaging information using the traditional approaches that take snapshots of time points from different animals. The goal of molecular imaging is to monitor the in situ, continuous molecular changes of cells in vivo. Therefore, the most advanced bioengineering lineage tracing approach, while using a variety of molecular detection methods, will maximize the presentation of CSC. In this review, we first introduce the method of lineage tracing, and then introduce the various components of molecular images to dynamic detect the CSC. Finally, we analyze the current situation and look forward the future of CSC detection.


Asunto(s)
Neoplasias , Células Madre Neoplásicas , Animales , Neoplasias/diagnóstico por imagen , Neoplasias/patología , Células Madre Neoplásicas/patología
20.
Langmuir ; 38(25): 7791-7801, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35687508

RESUMEN

Because of the high synthesis cost, strong chemical inertness, complex process, and easy to endanger environment of traditional carbon-based nanolubricant additives, the development of its application in lubrication is limited. Therefore, a new type of lubricant additive with low cost, high yield, high performance, and environmental protection is urgently needed. Herein, a kilogram-scale carbon dots (CDs) lubricant additive was prepared by a simple and green one-step reaction of aldol condensation, which showed excellent lubricating properties in water and sunflower oil. The tribological properties of the CDs lubricant additive at different concentrations, loads, and speeds were systematically studied. The results show that the average friction coefficient of water is significantly reduced by 75% by a CDs lubricant additive. In particular, CDs not only exhibited excellent service life and lubrication stability during friction but also kept the friction coefficient change rate of sunflower seed oil close to 0 within 500 min. According to the tribological evaluation and wear surface analysis, the lubrication mechanism of CDs was attributed to their own morphological characteristics and abundant oxygen-containing functional groups on the surface. In the friction process, the charge adsorption effect, the adsorption protective film, and the hydrogen bonding layer are generated, which play an essential role in obvious antiwear and friction reduction. Therefore, this work provides a reference for the preparation of high-performance and high-yield lubricant additives.

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