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1.
Molecules ; 29(14)2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39064919

RESUMEN

Tungsten disulfide (WS2) is a promising material with excellent electrical, magnetic, optical, and mechanical properties. It is regarded as a key candidate for the development of optoelectronic devices due to its high carrier mobility, high absorption coefficient, large exciton binding energy, polarized light emission, high surface-to-volume ratio, and tunable band gap. These properties contribute to its excellent photoluminescence and high anisotropy. These characteristics render WS2 an advantageous material for applications in light-emitting devices, memristors, and numerous other devices. This article primarily reviews the most recent advancements in the field of optoelectronic devices based on two-dimensional (2D) nano-WS2. A variety of advanced devices have been considered, including light-emitting diodes (LEDs), sensors, field-effect transistors (FETs), photodetectors, field emission devices, and non-volatile memory. This review provides a guide for improving the application of 2D WS2 through improved methods, such as introducing defects and doping processes. Moreover, it is of great significance for the development of transition-metal oxides in optoelectronic applications.

2.
Pharmaceutics ; 16(7)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-39065539

RESUMEN

The Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) causes reproductive failure and respiratory symptoms, leading to huge economic losses for the pig farming industry. Although several vaccines against PRRSV are available in the market; they show an overall low efficacy, and several countries have the need for vaccines covering the local, circulating variants. This project aims at developing a new chimeric antigen targeting specific epitopes from PRRSV and evaluating two test adjuvants to formulate a vaccine candidate. The test antigen was called LTB-PRRSV, which was produced recombinantly in Escherichia coli and consisted of the heat labile enterotoxin B subunit from E. coli (LTB) and four epitopes from PRRSV. LTB-PRRSV was rescued as inclusion bodies and methods for its solubilization, IMAC-based purification, and refolding were standardized, leading to mean yields of 18 mg of pure protein per liter culture. Layered double hydroxides (LDH) have been used as vaccine adjuvants given their biocompatibility, low cost, and positive surface charge that allows an efficient adsorption of negatively charged biomolecules. Therefore, LDH were selected as delivery vehicles of LTB-PRRSV. Pure LTB-PRRSV was adsorbed onto LDH by incubation at different LDH:LTB-PRRSV mass ratios (1:0.25, 1:0.5, 1:1, and 1:2) and at pH 9.5. The best adsorption occurred with a 1:2 mass ratio, and in a sucrose-tween solution. The conjugates obtained had a polydispersity index of 0.26, a hydrodynamic diameter of 192 nm, and a final antigen concentration of 64.2 µg/mL. An immunogenicity assessment was performed by injecting mice with LDH:LTB-PRRSV, Alum/LTB-PRRSV, or LTB-PRRSV in a scheme comprising three immunizations at two-week intervals and two dose levels (1 and 5 µg). LTB-PRRSV was capable of inducing strong humoral responses, which lasted for a longer period when LDH was used as the delivery vehicle/adjuvant. The potential of LDH to serve as an attractive carrier for veterinary vaccines is discussed.

3.
Pharmaceutics ; 16(7)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-39065574

RESUMEN

Palmitoylethanolamide (PEA) exhibits multiple skincare functions such as anti-nociceptive and anti-inflammatory effects. However, its topical application is limited due to its difficulty in bypassing the stratum corneum barrier, relatively low bioavailability, and low stability. Herein, elastic nano-liposomes (ENLs) with excellent deformability and elasticity were utilized as a novel drug delivery system to encapsulate PEA to overcome the abovementioned issues and enhance the biological effects on the skin. ENL was prepared with phosphatidylcholine, cholesterol, and cetyl-PG hydroxyethyl palmitamide with a molar ratio mimicking skin epidermal lipids, and PEA was loaded. The PEA-loaded ENL (PEA-ENL) demonstrated efficient transdermal delivery and enhanced skin retention, with negligible cytotoxicity toward HaCaT cells and no allergic reaction in the human skin patch test. Notably, PEA-ENL treatment increased cell migration and induced significant regulation in the expression of genes associated with anti-nociceptive, anti-inflammatory, and skin barrier repair. The mechanism of the anti-nociceptive and anti-inflammatory effects of PEA was further investigated and explained by molecular docking site analysis. This novel PEA-ENL, with efficient transdermal delivery efficiency and multiple skincare functionalities, is promising for topical application.

4.
Environ Pollut ; : 124619, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39067738

RESUMEN

Biochar (BC) has been proven effective in promoting the production of safety food in cadmium (Cd)-polluted soil and the impact can be further enhanced through interaction with compost (CM). However, there existed unclear impacts of biochar with varying particle sizes in conjunction with compost on microbiome composition, rhizosphere functions, and soil health. Hence, in this study, two bulk-biochar derived from wood chips and pig manure were fabricated into nano-biochar using a ball-milling method. Subsequently, in a field experiment, the root-associated bacterial community and microbial functions of lettuce were evaluated in respond to Cd-contaminated soil remediated with nano/bulk-BCCM. The results showed that compared to bulk-BCCM, nano-BCCM significantly reduced the Cd concentration in the edible part of lettuce and the available Cd in the soil. Both nano-BCCM and bulk-BCCM strongly influenced the composition of bacterial communities in the four root-associated niches, and enhanced rhizosphere functions involved in nitrogen, phosphorus, and carbon cycling, as well as the relative abundance and biodiversity of keystone modules in rhizosphere soil. Furthermore, soil quality index analysis indicated that nano-BCCM exhibited greater potential than bulk-BCCM in maintaining soil health. The data revealed that nano-BCCM could regulate the Cd concentration in lettuce shoot by promoting microbial biodiversity of keystone modules in soil-root continuum and rhizosphere bacterial functions. These findings suggest that nano-biochar compost associations can be a superior strategy for enhancing microbial functions, maintaining soil health, and ensuring crop production safety in the Cd-contaminated soil compared to the mix of bulk-biochar and compost.

5.
Anal Chim Acta ; 1318: 342896, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39067908

RESUMEN

Identifying ultra-trace amounts of divalent lead ions (Pb2+) with high response and selectivity, continues to be a pressing issue in identifying environmental pollutants and preventing health complications. This paper details how the in-situ electrodeposited Zn/Cu-BTC-NH2 metal-organic frameworks (MOFs) boosts Pb2+ concentration for amino adsorption and facilitates ion transfer between Cu element and Pb2+. The modified coating of the glassy carbon electrode (GCE) exhibits a unique nano-reticulated structure loaded with octahedron particles, the nano-reticulated structure ensures the structural strength of the modified electrode layer, while the loaded octahedral particles enhancing electrocatalytic activity. The ultra-trace detection of Pb2+ at concentrations below µg·L-1 is accomplished by using the square wave anodic stripping voltammetry (SWASV) method, the fabricated Zn/Cu-BTC-NH2 modified electrode signifies a detection threshold of 0.021 µg L-1 and a clearly ascending linear interval prior to the rise in Pb2+ concentration to 120 µg L-1. The reported electrochemical method for the precise identification of Pb2+ in water-based solutions offers a practical approach for modifying MOFs materials and detecting heavy metal ions.

6.
Int J Biol Macromol ; 277(Pt 2): 134135, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39069033

RESUMEN

Chemotherapy remains one of the most commonly used strategies in cancer treatment but suffers from damages to healthy tissues and organs. How to precisely co-deliver two or more drugs with different mechanisms of action to the tumors for synergistic function is a challenge for chemotherapy. Herein, Oleanolic acid (OA)-conjugated Hyaluronic acid self-assembled nano-micelles loaded with Doxorubicin (DOX) (HSO NPs/DOX) were constructed for CD44 positive cancer targeted codelivery of DOX and OA. HSO NPs/DOX exhibited reduction triggered drug release under high concentration of glutathione, more efficient uptake by 4T1 breast cancer cells than free DOX leading to higher cytotoxicity, pro-apoptotic, and migration inhibitory activities against 4T1 cells. The ex vivo biodistribution experiment demonstrated more HSO NPs/DOX were accumulated in the tumor tissues than free DOX and less in the non-tumor tissues after injections in 4T1 tumor bearing mice. More importantly, synergistic anti-tumor effects of DOX and OA were obtained using HSO NPs/DOX in 4T1 breast tumor-bearing mice and toxicity of DOX to liver and heart were circumvented through regulating the Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB) and Silent Information Regulator 1 (Sirt1) expressions. Taken together, HSO NPs/DOX may become a promising codelivery system for chemotherapeutics in cancer therapy.

7.
Bioresour Technol ; 408: 131168, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39069143

RESUMEN

The partial-denitrification-anammox (PdNA) process exhibits great potential in enabling the simultaneous removal of NO3--N and NH4+-N. This study delved into the impact of exogenous nano zero-valent iron (nZVI) on the PdNA process. Adding 10 mg L-1 of nZVI increased nitrogen removal efficiency up to 83.12 % and maintained higher relative abundances of certain beneficial bacteria. The maximum relative abundance of Candidatus Brocadia (1.6 %), Candidatus Kuenenia (1.5 %), Ignavibacterium (1.3 %), and Azospira (1.2 %) was observed at 10 mg L-1 of nZVI. However, the greatest relative abundance of Thauera (1.3 %) was recorded under 50 mg L-1. Moreover, applying nZVI selectively enhanced the abundance of NO3--N reductase genes. So, keeping the nZVI concentration at 10 mg L-1 or below is advisable to ensure a stable PdNA process in mainstream conditions. Considering nitrogen removal efficiency, using nZVI in the PD-anammox process could be more cost-effective in enhancing its adoption in industrial and mainstream settings.

8.
Med Oncol ; 41(9): 210, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39060753

RESUMEN

According to the World Health Organization, cancer is the foremost cause of mortality globally. Various phytochemicals from natural sources have been extensively studied for their anticancer properties. Allicin, a powerful organosulfur compound derived from garlic, exhibits anticancer, antioxidant, anti-inflammatory, antifungal, and antibacterial properties. This review aims to update and evaluate the chemistry, composition, mechanisms of action, and pharmacokinetics Allicin. Allicin has garnered significant attention for its potential role in modulating Fas-FasL, Bcl2-Bax, PI3K-Akt-mTOR, autophagy, and miRNA pathways. At the molecular level, allicin induces the release of cytochrome c from the mitochondria and enhances the activation of caspases-3, -8, and -9. This is accompanied by the simultaneous upregulation of Bax and Fas expression in tumor cells. Allicin can inhibit excessive autophagy by activating the PI3K/Akt/mTOR and MAPK/ERK/mTOR signaling pathways. Allicin-loaded nano-formulations efficiently induce apoptosis in cancer cells while minimizing toxicity to normal cells. Safety and clinical aspects are meticulously scrutinized, providing insights into the tolerability and adverse effects associated with allicin administration, along with an overview of current clinical trials evaluating its therapeutic potential. In conclusion, this review underscores the promising prospects of allicin as a dietary-derived medicinal compound for cancer therapy. It emphasizes the need for further research to elucidate its precise mechanisms of action, optimize delivery strategies, and validate its efficacy in clinical settings.


Asunto(s)
Apoptosis , Disulfuros , Neoplasias , Transducción de Señal , Ácidos Sulfínicos , Ácidos Sulfínicos/farmacología , Ácidos Sulfínicos/uso terapéutico , Humanos , Apoptosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neoplasias/metabolismo , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico
9.
Animals (Basel) ; 14(14)2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39061509

RESUMEN

The rapid progress of the modern world has resulted in new materials and products created at an accelerating pace. As such, nanoparticles have widespread applications and often find their way into the aquatic ecosystem. In the case of freshwater ecosystems, one of the commonly used bioindicators species used for pollution assessment is Daphnid magna. The Organization for Economic Co-operation and Development (OECD), and other organizations such as the European Chemicals Agency (ECHA) and Environmental Protection Agency (EPA), have set guidelines for acute toxicity testing in daphnids that are severely lacking in terms of information on the characteristics of the exposure vessel when studying the adverse effects of nanoparticles (NPs). Understanding the toxicity mechanisms of nanomaterials is imperative given the scarcity of information on their adverse effects. Furthermore, miniaturization of nanotoxicity assays can reduce the number of daphnids used, as well as the cost and nanomaterial waste, and provide results even at the individual animal level with enhanced reproducibility of testing. In this study, the impact of the exposure vessel on the observed physiological changes of daphnids was investigated for a silver nano ink. Exposures in eleven commercially available vessels; nine made of plastic and two made of glass were compared for 24 h. The effect of surface to volume ratio of the exposure vessel and the animal number or "crowding" during exposure was investigated in the context of miniaturizing biomarker assays as alternatives to traditional experimental setups in Daphnid magna. Toxicity curves showed differences depending on the vessel used, while a novel feeding rate assay and the activity of key enzymes were assessed as physiology endpoints.

10.
Biomedicines ; 12(7)2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-39062077

RESUMEN

Atherosclerosis is a common form of cardiovascular disease, which is one of the most prevalent causes of death worldwide, particularly among older individuals. Surgery is the mainstay of treatment for severe stenotic lesions, though the rate of restenosis remains relatively high. Current medication therapy for atherosclerosis has limited efficacy in reversing the formation of atherosclerotic plaques. The search for new drug treatment options is imminent. Some potent medications have shown surprising therapeutic benefits in inhibiting inflammation and endothelial proliferation in plaques. Unfortunately, their use is restricted due to notable dose-dependent systemic side effects or degradation. Nevertheless, with advances in nanotechnology, an increasing number of nano-related medical applications are emerging, such as nano-drug delivery, nano-imaging, nanorobots, and so forth, which allow for restrictions on the use of novel atherosclerotic drugs to be lifted. This paper reviews new perspectives on the targeted delivery of nanoparticles to blood vessels for the treatment of atherosclerosis in both systemic and local drug delivery. In systemic drug delivery, nanoparticles inhibit drug degradation and reduce systemic toxicity through passive and active pathways. To further enhance the precise release of drugs, the localized delivery of nanoparticles can also be accomplished through blood vessel wall injection or using endovascular interventional devices coated with nanoparticles. Overall, nanotechnology holds boundless potential for the diagnosis and treatment of atherosclerotic diseases in the future.

11.
ACS Nano ; 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39079080

RESUMEN

The mechanical properties of nanoparticles play a crucial role in regulating nanobiointeractions, influencing processes such as blood circulation, tumor accumulation/penetration, and internalization into cancer cells. Consequently, they have a significant impact on drug delivery and therapeutic efficacy. However, it remains unclear whether and how macrophages alter their biological function in response to nanoparticle elasticity. Here, we report on the nano-mechanical biological effects resulting from the interactions between elastic silica nanoparticles (SNs) and macrophages. The SNs with variational elasticity Young's moduli ranging from 81 to 837 MPa were synthesized, and it was demonstrated that M2 [tumor-associated macrophages (TAMs)] could be repolarized to M1 by the soft SNs. Additionally, our findings revealed that cell endocytosis, membrane tension, the curvature protein Baiap2, and the cytoskeleton were all influenced by the elasticity of SNs. Moreover, the mechanically sensitive protein Piezo1 on the cell membrane was activated, leading to calcium ion influx, activation of the NF-κB pathway, and the initiation of an inflammatory response. In vivo experiments demonstrated that the softest 81 MPa SNs enhanced tumor penetration and accumulation and repolarized TAMs in intratumoral hypoxic regions, ultimately resulting in a significant inhibition of tumor growth. Taken together, this study has established a cellular feedback mechanism in response to nanoparticle elasticity, which induces plasma membrane deformation and subsequent activation of mechanosensitive signals. This provides a distinctive "nano-mechanical immunoengineering" strategy for reprogramming TAMs to enhance cancer immunotherapy.

12.
Transl Oncol ; 48: 102058, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39079408

RESUMEN

BACKGROUND: The efficacy of immunotherapy plus neoadjuvant chemotherapy and concurrent chemoradiotherapy (CCRT) for locally advanced nasopharyngeal carcinoma (LA-NPC) has not been reported. This study retrospectively compared the efficacy of tislelizumab plus neoadjuvant chemotherapy and CCRT with neoadjuvant chemotherapy followed by CCRT. METHODS: Ninety patients with stages III-IVa NPC were identified between January 2020 and March 2021 at the Affiliate Hospital of Guangdong Medical University. Forty-three patients in the observation group (OG) received tislelizumab plus nano albumin-paclitaxel and cisplatin (nab-TP) regimen, followed by CCRT, while forty-seven patients in the control group (CG) received nab-TP regimen followed by CCRT. RESULTS: The complete response rate after neoadjuvant therapy was significantly higher in the OG compared to the CG (37.2% vs. 12.8 %). The objective response rates were 88.4 % in the OG and 70.2 % in the CG. The 3-year progression-free survival (PFS) rates for OG and CG patients were 93.0 % and 78.7 %, respectively (P = 0.04, HR = 0.31). The overall survival (OS) rates for the OG and the CG were 95.3 % and 87.2 %, respectively (P = 0.15, HR = 0.36). Locoregional relapse-free survival (LRFS) rates were 90.7 % for the OG and 72.3 % for the CG (P = 0.04, HR = 0.38), and distant metastasis-free survival (DMFS) rates were 95.3 % for the OG, and 80.9 % for the CG (P = 0.04, HR = 0.30). For PD-L1 high-expression and low-expression rates, the 3-year PFS rates were 89.2 % and 85.7 % (P = 0.77, HR = 1.21), and the OS rates were 90.2 % and 89.2 % (P = 0.65, HR = 1.36), respectively. CONCLUSION: Tislelizumab combined with neoadjuvant chemotherapy and CCRT showed encouraging therapeutic effects and good tolerability in patients with LA-NPC compared to the standard treatment.

13.
J Nanobiotechnology ; 22(1): 452, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080641

RESUMEN

Drug resistance to chemotherapy in cancers remains significant clinical challenges. CD44 modulates cellular adhesion, migration and growth, which plays a pivotal role in driving cancer resistance and even recurrence. Despite ongoing efforts, accurate, safe, and real-time dynamic monitoring techniques for CD44 expression remain inadequate in guiding the management of drug-resistant cancer treatment. In this study, we developed a nano-quenching and recovery detector of CD44 (Cy3-AptCD44@BPNSs) for visualizing cancer drug resistance. The fluorescence recovery of the detector is directly related to the CD44 expression level on cancer cells, which can be used to indicate the degree of drug resistance. It's confirmed that downregulating CD44 expression on cancer cells results in a corresponding decrease in the fluorescence intensity of the detector, which enables precise and dynamic monitoring of CD44. In addition, the Cy3-AptCD44@BPNSs also exhibited specificity in detecting CD44. This visualizing strategy may open up a wide range of possibilities for rapid recognition to cancer drug resistance, which is more efficient and flexible.


Asunto(s)
Resistencia a Antineoplásicos , Receptores de Hialuranos , Receptores de Hialuranos/metabolismo , Humanos , Línea Celular Tumoral , Neoplasias/tratamiento farmacológico , Fluorescencia , Antineoplásicos/farmacología
14.
Foods ; 13(14)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39063352

RESUMEN

Chromatographic analysis of phenolic phytochemicals in foods has significantly advanced over the past decade (2014-2024), meeting increasing demands for precision and efficiency. This review covers both conventional and advanced chromatographic techniques used for detecting phenolic phytochemicals in foods. Conventional methods like High-Performance Liquid Chromatography, Ultra High-Performance Liquid Chromatography, Thin-Layer Chromatography, and Gas Chromatography are discussed, along with their benefits and limitations. Advanced techniques, including Hydrophilic Interaction Liquid Chromatography, Nano-LC, Multidimensional Liquid Chromatography, and Capillary Electrophoresis, are highlighted for their innovations and improved capabilities. The review addresses challenges in current chromatographic methods, emphasizing the need for standardized and validated procedures according to the Food and Drug Administration, European Cooperation for Accreditation of Laboratories, and The International Organization for Standardization guidelines to ensure reliable and reproducible results. It also considers novel strategies for reducing the environmental impact of chromatographic methods, advocating for sustainable practices in analytical chemistry.

15.
Foods ; 13(14)2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39063387

RESUMEN

Plant proteins have gained significant attention over animal proteins due to their low carbon footprint, balanced nutrition, and high sustainability. These attributes make plant protein nanocarriers promising for applications in drug delivery, nutraceuticals, functional foods, and other areas. Zein, a major by-product of corn starch processing, is inexpensive and widely available. Its unique self-assembly characteristics have led to its extensive use in various food and drug systems. Zein's functional tunability allows for excellent performance in loading and transporting bioactive substances. Lutein offers numerous bioactive functions, such as antioxidant and vision protection, but suffers from poor chemical stability and low bioavailability. Nano-embedding technology can construct various zein-loaded lutein nanodelivery systems to address these issues. This review provides an overview of recent advances in the construction of zein-loaded lutein nanosystems. It discusses the fundamental properties of these systems; systematically introduces preparation techniques, structural characterization, and functional properties; and analyzes and predicts the target-controlled release and bioaccessibility of zein-loaded lutein nanosystems. The interactions and synergistic effects between Zein and lutein in the nanocomplexes are examined to elucidate the formation mechanism and conformational relationship of zein-lutein nanoparticles. The physical and chemical properties of Zein are closely related to the molecular structure. Zein and its modified products can encapsulate and protect lutein through various methods, creating more stable and efficient zein-loaded lutein nanosystems. Additionally, embedding lutein in Zein and its derivatives enhances lutein's digestive stability, solubility, antioxidant properties, and overall bioavailability.

16.
Materials (Basel) ; 17(14)2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39063735

RESUMEN

Dental composites are gaining great popularity in restorative dentistry because of their aesthetic appeal and capacity to replicate the natural color of teeth. Nevertheless, their lifespan and durability rely on various factors, such as the polishing technique and the environmental conditions they are exposed to. The study aimed to assess the influence of the method of final polishing of dental composite on the surface roughness and microhardness of materials also considering the environment of different pHs. Disc-shaped samples (5 mm diameter and 2 mm thickness) have been prepared for microhardness and roughness tests from two dental composites: A2 Clearfil Majesty ES 2 Classic and A2D Clearfil Majesty Premium. One-third of samples were polished with polishing discs, OptiDisc, another one-third of samples were polished with Eve Diacomp Twist rubbers and polishing brush with diamond particles, and rest of the samples were stored without any polishing (the control group). Tested materials were incubated in distilled water or acidic buffer (pH = 2) for 3 weeks at a temperature of 37 °C. No statistically significant differences were found for roughness for the two materials tested after incubation in liquids. A decrease in Vicker microhardness was found for Clearfil Majesty ES 2 Classic after soaking in a low pH liquid, and no such relationship was found for Clearfil Majesty Premium. The improved resistance of these materials to the negative oral environment may result in the longer survival of composite restorations in patients with poor diet or diseases, causing a decrease in oral pH.

17.
Materials (Basel) ; 17(14)2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39063745

RESUMEN

As an important part of die steels, hot-work die steels are mainly used to manufacture molds made of solid metal or high-temperature liquid metal from heating to recrystallization temperature. In view of the requirements for mechanical properties and service life for hot-work die steel, it is conducive to improve the thermal fatigue resistance, wear resistance, and oxidation resistance of hot work die steel. In this review, the main failure modes of hot-work die steel were analyzed. Four traditional methods of strengthening and toughening die steel were summarized, including optimizing alloying elements, electroslag remelting, increasing the forging ratio, and heat treatment process enhancement. A new nano-strengthening method was introduced that aimed to refine the microstructure of hot-work abrasive steel and improve its service performance by adding nanoparticles into molten steel to achieve uniform dispersion. This review provides an overview to improve the service performance and service life of hot work die steel.

18.
Materials (Basel) ; 17(14)2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39063784

RESUMEN

In this study, the impact of the addition of high-aspect-ratio nano-ettringite to photocurable epoxy acrylate resin was explored. The nano-ettringite samples were modified using γ-Aminopropyltriethoxysilane (KH-550) and γ-methacryloxypropyl trimethoxy silane (KH-570). Then, 3 wt% or 6 wt% KH-550-modified, KH-570-modified, and unmodified nano-ettringite samples were dispersed into resin via ultrasonic treatment in conjunction with mechanical stirring. The grafting effects of nano-ettringite onto KH-550 or KH-570 were analyzed through scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and thermogravimetric (TG) analysis. The results demonstrate that KH-550 and KH-570 have been successfully grafted onto the surface of nano-ettringite. In addition, this study also focuses on the variations of composite materials in the viscosity, shrinkage, tensile strength, and elongation at break. The results indicate that increased dosages of unmodified, KH-550-modified, and KH-570-modified nano-ettringite led to increased viscosity of the composite while reducing shrinkage. At the same dosage, the photocurable resin containing KH-570-modified nano-ettringite demonstrated a lower shrinkage and a higher tensile strength. From the analysis of tensile fracture surfaces, it was observed that compared to the KH-550 modified and unmodified variants, the KH-570 modified nano-ettringite exhibits superior dispersibility in photocurable epoxy acrylate resin. Notably, when the amount of KH-570-modified nano-ettringite was 3 wt%, the highest tensile strength of the composite was 64.61 MPa, representing a 72.57% increase compared to the blank sample. Furthermore, the incorporation of KH-570-modified nano-ettringite as a filler provides a new perspective for improving the performance of photocurable epoxy acrylate resin composites.

19.
Micromachines (Basel) ; 15(7)2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39064425

RESUMEN

The high-efficiency preparation of large-area microstructures of optical materials and precision graphic etching technology is one of the most important application directions in the atomic and near-atomic-scale manufacturing industry. Traditional focused ion beam (FIB) and reactive ion etching (RIE) methods have limitations in precision and efficiency, hindering their application in automated mass production. The pulsed ion beam (PIB) method addresses these issues by enhancing ion beam deflection to achieve high-resolution material removal on a macro scale, which can reach the equivalent removal resolution of 6.4 × 10-4 nm. Experiments were conducted on a quartz sample (10 × 10 × 1 mm) with a specific pattern mask using the custom PIB processing device. The surface morphology, etching depth, and roughness were measured post-process. The results demonstrated that precise control over cumulative sputtering time yielded well-defined patterns with expected average etching depths and surface roughness. This confirms the PIB technique's potential for precise atomic depth image transfer and its suitability for industrial automation, offering a significant advancement in microfabrication technology.

20.
Int J Nanomedicine ; 19: 6337-6358, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38946884

RESUMEN

Background: It is well-established that osteoclast activity is significantly influenced by fluctuations in intracellular pH. Consequently, a pH-sensitive gated nano-drug delivery system represents a promising therapeutic approach to mitigate osteoclast overactivity. Our prior research indicated that naringin, a natural flavonoid, effectively mitigates osteoclast activity. However, naringin showed low oral availability and short half-life, which hinders its clinical application. We developed a drug delivery system wherein chitosan, as gatekeepers, coats mesoporous silica nanoparticles loaded with naringin (CS@MSNs-Naringin). However, the inhibitory effects of CS@MSNs-Naringin on osteoclasts and the underlying mechanisms remain unclear, warranting further research. Methods: First, we synthesized CS@MSNs-Naringin and conducted a comprehensive characterization. We also measured drug release rates in a pH gradient solution and verified its biosafety. Subsequently, we investigated the impact of CS@MSNs-Naringin on osteoclasts induced by bone marrow-derived macrophages, focusing on differentiation and bone resorption activity while exploring potential mechanisms. Finally, we established a rat model of bilateral critical-sized calvarial bone defects, in which CS@MSNs-Naringin was dispersed in GelMA hydrogel to achieve in situ drug delivery. We observed the ability of CS@MSNs-Naringin to promote bone regeneration and inhibit osteoclast activity in vivo. Results: CS@MSNs-Naringin exhibited high uniformity and dispersity, low cytotoxicity (concentration≤120 µg/mL), and significant pH sensitivity. In vitro, compared to Naringin and MSNs-Naringin, CS@MSNs-Naringin more effectively inhibited the formation and bone resorption activity of osteoclasts. This effect was accompanied by decreased phosphorylation of key factors in the NF-κB and MAPK signaling pathways, increased apoptosis levels, and a subsequent reduction in the production of osteoclast-specific genes and proteins. In vivo, CS@MSNs-Naringin outperformed Naringin and MSNs-Naringin, promoting new bone formation while inhibiting osteoclast activity to a greater extent. Conclusion: Our research suggested that CS@MSNs-Naringin exhibited the strikingly ability to anti-osteoclasts in vitro and in vivo, moreover promoted bone regeneration in the calvarial bone defect.


Asunto(s)
Regeneración Ósea , Flavanonas , Nanopartículas , Osteoclastos , Dióxido de Silicio , Flavanonas/química , Flavanonas/farmacología , Flavanonas/farmacocinética , Flavanonas/administración & dosificación , Animales , Osteoclastos/efectos de los fármacos , Regeneración Ósea/efectos de los fármacos , Dióxido de Silicio/química , Concentración de Iones de Hidrógeno , Nanopartículas/química , Ratas , Ratones , Ratas Sprague-Dawley , Quitosano/química , Masculino , Liberación de Fármacos , Porosidad , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Resorción Ósea/tratamiento farmacológico , Células RAW 264.7 , Sistemas de Liberación de Medicamentos/métodos , Diferenciación Celular/efectos de los fármacos
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