Search Results (724)

Bone metastases continue to be a major cause of morbidity and mortality in patients with advanced cancers, driven by the dynamic remodeling of the bone marrow niche. Traditionally viewed as passive space-fillers, bone marrow adipocytes (BMAs) are now recognized as active regulators of tumor growth, therapeutic resistance, and skeletal pathology. BMAs comprise a significant portion of the adult marrow space, particularly in aging and obesity, and facilitate metastatic colonization through various mechanisms. These include metabolic coupling, where adipocyte-derived fatty acids fuel tumor oxidative phosphorylation; the secretion of adipokines such as leptin and IL-6, which promote epithelial-to-mesenchymal transition, invasion, and immune evasion; regulation of osteoclastogenesis via RANKL expression; and the release of extracellular vesicles that reprogram cancer cell metabolism. Clinical and experimental studies show that BMA expansion correlates with increased tumor burden and poorer outcomes in breast, prostate, lung cancers, and multiple myeloma. Additionally, BMAs actively promote therapeutic resistance through metabolic rewiring and drug sequestration. Experimental models, ranging from in vitro co-cultures to in vivo patient-derived xenografts, demonstrate the complex roles of BMAs and also reveal important translational gaps. Despite promising preclinical approaches such as metabolic inhibitors, PPARγ modulation, adipokine blockade, and lifestyle changes, no therapies directly targeting BMAs have yet reached clinical practice. This review compiles current evidence on the biology of BMAs, their tumor-promoting interactions, and potential therapeutic strategies, while also highlighting unresolved questions about BMA heterogeneity, lipid flux, and immunometabolic crosstalk. By revealing how bone marrow adipocytes actively shape the metastatic niche through metabolic, endocrine, and immunological pathways, this review highlights their potential as novel biomarkers and therapeutic targets for improving the management of bone metastases. Full article

For the first time, the kinetics of isothermal curing and thermal degradation of polyethylene glycol maleate (pEGM)–based systems and their composites with mineral fillers were investigated in the presence of a benzoyl peroxide/N,N-Dimethylaniline redox-initiating system. DSC analysis revealed that the curing process at 20 °C can be described by the modified Kamal autocatalytic model; the critical degree of conversion (α_c) decreases with increasing content of the unsaturated polyester pEGM and in the presence of fillers. In particular, for unfilled systems, α_c was 0.77 for pEGM45 and 0.60 for pEGM60. TGA results demonstrated that higher pEGM content and the incorporation of fillers lead to increased thermal stability and residual mass, along with a reduction in the maximum decomposition rate (dTGₘₐₓ). Calculations using the Kissinger–Akahira–Sunose and Friedman methods also confirmed an increase in the activation energy of thermal degradation (E_a): E_KAS was 419 kJ/mol for pEGM45 and 470 kJ/mol for pEGM60, with the highest values observed for pEGM60 systems with fillers (496 kJ/mol for SiO₂ and 514 kJ/mol for CaCO₃). Rheological studies employing three-interval thixotropy tests revealed the onset of thixotropic behavior upon filler addition and an increase in structure recovery after deformation of up to 56%. These findings underscore the potential of pEGM-based systems for low-temperature curing and for the design of composite materials with improved thermal resistance. Full article

Background: Hyaluronic acid (HA) dermal fillers are among the most widely used injectable materials in esthetic medicine. They are generally safe, but delayed inflammatory reactions (DIRs) have been observed, particularly after viral infections or vaccinations. Such events have raised questions about the role of immune activation in filler-related complications. Objective: This review examined the available literature on DIRs to HA fillers that occurred in the context of viral illness or immunization, with attention to how these reactions present and how they are managed. Methods: A systematic search was carried out in PubMed, ScienceDirect, ClinicalKey, and Google Scholar between October and November 2024. Only human case reports and case series were included. The protocol was registered in PROSPERO (CRD420251030918), and study quality was assessed using the Newcastle–Ottawa Scale. Results: Six publications met inclusion criteria: four case series and two case reports, describing 25 women between 22 and 65 years of age. Patients developed swelling, erythema, angioedema, or, in severe cases, marked facial edema after HA filler injections, with symptom onset ranging from several hours to several weeks following viral exposure. Corticosteroids and hyaluronidase were the most common treatments, though milder cases sometimes resolved without intervention. Study quality varied, with some reports providing limited detail on patient characteristics and follow-up. Conclusions: DIRs associated with viral infections or vaccinations remain uncommon but clinically relevant complications of HA filler use. Limited case-based evidence indicates potential effectiveness of corticosteroids and hyaluronidase, though management practices remain inconsistent. Larger prospective studies are needed to clarify underlying mechanisms and to establish standardized guidelines for treatment. Full article

The pursuit of sustainable and environmentally benign energy storage solutions has propelled significant interest in organic batteries, which utilize redox-active organic compounds as electrode materials. A pivotal component in determining their electrochemical performance, safety, and long-term stability is the electrolyte. Polymer-based electrolytes (PBEs) have emerged as promising candidates owing to their intrinsic advantages, such as enhanced thermal stability, mechanical integrity, and the mitigation of leakage and flammability risks associated with conventional liquid electrolytes. Unlike previous reviews that broadly cover solid electrolytes, this review specifically focuses on the unique developments of polymer-based electrolytes tailored for organic batteries over the past few years. This review presents a comprehensive overview of the recent progress in PBEs specifically designed for organic battery systems. It systematically examines various categories, including solid polymer electrolytes (SPEs), valued for their structural simplicity and stability; gel polymer electrolytes (GPEs), noted for their high ionic conductivity and processability; and polymer-inorganic composite electrolytes, which synergistically integrate the mechanical flexibility of polymers with the ionic conductivity of inorganic fillers. Additionally, the review delves into the latest advancements in ionogels and poly(ionic liquid) electrolytes, highlighting their potential to overcome existing limitations and enable next-generation battery performance. The article concludes with a critical discussion on prevailing challenges and prospective research directions, emphasizing the importance of advanced material design, interfacial engineering, and sustainable synthesis approaches to facilitate the practical realization of high-performance organic batteries. Full article

Objective: This study aimed to evaluate the effect of incorporating bioactive particles (montmorillonite loaded with chlorhexidine, MMT/CHX) and different concentrations of silica nanoparticles (0%, 3%, 5%, 7%, 10%, and 15 wt%) into a universal dental adhesive on its degree of conversion, bond strength, water sorption, solubility, and antimicrobial activity. Materials and Methods: A universal adhesive was modified with 1 wt% MMT/CHX and varying amounts of silica nanoparticles. Degree of conversion was analyzed by Fourier transform infrared spectroscopy (FTIR), and microtensile bond strength was evaluated at 24 h, 6 months, and 12 months after water storage. Water sorption and solubility were measured according to ISO 4049, and antibacterial activity was tested against Streptococcus mutans using the agar diffusion method. Results: All experimental adhesives containing ≥7% silica showed significantly reduced water sorption and solubility. The presence of MMT/CHX imparted consistent antimicrobial activity across all experimental groups. Degree of conversion remained stable across all groups and storage periods. Notably, after 12 months, only the experimental groups maintained or improved bond strength, while the control group showed a significant reduction. Failure mode analysis indicated increased mechanical integrity with higher filler content. Conclusions: Incorporating 1 wt% MMT/CHX and ≥7 wt% silica into a universal adhesive improved long-term bond strength, reduced degradation, and introduced antibacterial properties without compromising polymer conversion. These findings support the potential of developing durable, bioactive adhesive systems for restorative dentistry. Clinical Significance: The incorporation of bioactive and reinforcing nanoparticles into universal adhesives enhances bond durability and introduces antibacterial properties without compromising polymerization. This innovation may lead to longer-lasting restorations and reduced risk of secondary caries in clinical practice. Full article

With aging, harsh working conditions or sports injuries, the meniscus can degrade, causing pains to the patient. Nowadays, the treatment consists of the surgical replacement of this cartilage. Since this procedure can lead to complications due to open wounds and potential infections, synthesizing a polyurethane-based injectable joint filler represents an interesting alternative. In this study, poly(δ-decalactone)triol oligomers and Lysine diisocyanate were chosen as starting monomers to create an isocyanate-based prepolymer, because of their biocompatibility and liquid state at room temperature. Nevertheless, to fully replace the meniscus, the joint filler must crosslink in vivo, and this should occur in a short time window. Accordingly, in this work, we studied the catalytic activity of a range of relatively safe compounds for the alcohol/isocyanate addition reaction. A preliminary ¹H NMR kinetic study of the catalyzed addition of 1-butanol or 3-pentanol on lysine diisocyanate ethyl ester at body temperature has been performed to reach this objective. Among catalysts, stannous octoate was the most effective with either primary or secondary alcohol, allowing them to reach 92 and 80% alcohol conversion, respectively. In addition, the conversion of the primary and secondary isocyanates of lysine diisocyanate ethyl ester was monitored for all the catalysts and revealed different behaviors depending on the catalyst employed. Stannous octoate, unlike the others, showed a similar reactivity for primary and secondary isocyanates with conversions of 49 and 47%, respectively. Finally, when employing the most effective catalyst, curing of the poly(δ-decalactone) triisocyanate with glycerol at 35 °C provided a polyurethane elastomer that exhibits an elastic modulus of 519 kPa and a swelling index lower than 3% in PBS, making it suitable for injectable polyurethane joint filler application. Full article

Polymer-based hybrid composites have emerged as promising platforms for multifunctional energy applications, combining structural versatility with tunable dielectric behavior. In this study, synthesized [Fe(bpy)₃]SO₄; (tris(2,2′-bipyridine)iron(II) sulfate) coordination compound was incorporated into a green epoxy resin matrix to fabricate nanocomposites aimed at enhancing dielectric permittivity (ε′), piezoelectric coefficient (d₃₃, pC/N), energy-storage efficiency (n_rel, %), and mechanical strength (σ, MPa). The integration of the Fe(II) complex via Scanning Electron Microscopy (SEM) confirmed a homogeneous dispersion within the matrix. Broadband Dielectric Spectroscopy (BDS) revealed the presence of three relaxation processes in the spectra of the tested systems, demonstrating enhanced dielectric permittivity with increasing Fe(II) content. Under progressively shorter relaxation times (τ, s), key processes such as interfacial polarization, the polymer matrix’s transition from a glassy to a rubbery state, and the dynamic reorganization of polar side groups along the polymer backbone are activated. The ability to store and retrieve electric energy was confirmed by varying filler content under direct current (dc) conditions. The nanocomposite with 10 phr (mass parts/100 mass parts of resin) filler achieved a piezoelectric coefficient of d₃₃ = 5.1 pC/N, an energy-storage efficiency of n_rel = 44%, and a tensile strength of σ = 55.5 MPa, all of which surpass values reported for conventional epoxy-based composites. These results confirm the ability of the system to store and retrieve electric energy under direct current (dc) fields, while maintaining mechanical robustness and thermal stability due to synergistic interactions between the epoxy matrix and the Fe(II) complex. The multifunctional behavior of the composites underscores their potential as advanced materials for integrated dielectric, piezoelectric, and energy storage and harvesting applications. Full article

Background/Objectives: Enteric coating protects active pharmaceutical ingredients from gastric degradation, but conventional tablets may present swallowing difficulties in geriatric and pediatric patients. Hence, this study intended to develop pH-responsive multiparticulates, formulated into orally disintegrating tablets (ODTs), for targeted intestinal drug delivery in individuals with dysphagia. Methods: Multiparticulates were developed via sequential seal coating, drug layering, sub-coating, and enteric coating on inert cores using a fluidized bed coater (Pam Glatt, India; bottom spray). Selected enteric-coated batches were directly compressed into ODTs using microcrystalline cellulose (Avicel PH102) and mannitol (Pearlitol SD 160) as fillers, with Explotab^®, Ac-Di-Sol^®, or crospovidone M^® as superdisintegrants. Results: Multiparticulates exhibited mean diameters of 197.671–529.511 μm and span values of 0.603–0.838. Span value < 1, indicating a narrow size distribution. Electron microscopy confirmed the spherical morphology of Batches 7a and b. Enteric-coated batches (5b, 6, 7a, 7b) released ≤10% of the drug in 0.1 N HCl at 2 h. Optimized formulation ODT 7b released 7.904% of the drug under gastric conditions and 79.749% in phosphate buffer (pH 6.8) within 2.5 h, following first-order drug release kinetics. ODT 7b demonstrated hardness (2.538 ± 0.144 kg/cm²), wetting time (11.17 ± 1.051 s), friability (0.712%), and drug content (99.81 ± 1.01%) within acceptable limits. Conclusions: The pH-dependent multiparticulates provided sustained intestinal drug release and, when incorporated into ODTs, yielded a dosage form with a rapid wetting time and acceptable mechanical properties. This dosage form can offer a promising approach for improving compliance and therapeutic efficacy in patients with swallowing difficulties (dysphagia). Full article

Nano-silica (NS) is used to enhance the mechanical and durability properties of cementitious materials; however, its frequent tendency to agglomerate limits its effectiveness and uniform distribution within the cement matrix. The main goal of this study was to improve NS dispersion and therefore to improve the properties of the concrete by coating NS onto standard sand particles (sand@NS) using the Stöber method, creating a composite material that acts as a filler, nucleation site, and highly reactive pozzolanic agent. The resulting sand@NS was incorporated into cement mixtures, and its compressive strength was measured after 3, 7, and 28 days of curing. In addition, water absorption and microstructural density were also evaluated. Comparative results showed that sand@NS significantly enhanced early-age hydration and initial strength, with a 145% increase in compressive strength at 28 days compared to the reference, whereas free NS resulted in a 120% increase. The early-age strength improvement was mainly due to the increased number of nucleation centers, while later strength gains were attributed to pozzolanic activity of the immobilized NS. Additionally, sand@NS reduced water absorption and increased microstructural density, even with reduced cement content, supporting more sustainable and eco-efficient concrete production. This work shows a promising, scalable, and cost-effective strategy to maximize the performance of NS in cementitious systems and supports its broader adoption in advanced construction materials. Full article

This work aimed to synthesize rigid polyurethane foams with improved functional properties through modification with the addition of cellulose in the form of straw: unmodified, silanized, and silanized with the addition of fumed silica. The prepared rigid polyurethane foams contained 0.5; 1; and 3 parts by weight of the modifier about the weight of the polyol used. As part of the work, a number of tests were carried out to determine the impact of the modifiers used on the reaction kinetics and on the functional properties of rigid polyurethane foams. Silanization improved thermal stability and interfacial compatibility, while silica further enhanced porosity and surface activity. The optimal properties were obtained at low loadings: 0.5 wt.% provided the best mechanical strength, and 1 wt.% yielded the most uniform cell morphology and density. Higher contents increased porosity, reduced strength, and lowered water resistance. Dynamic mechanical analysis confirmed predominantly elastic behavior, with silica-modified fillers offering the most stable thermomechanical response. Overall, even small amounts of modified straw enhanced mechanical, structural, and water-resistant properties, demonstrating its potential as a sustainable and cost-effective biofiller for eco-friendly polyurethane foams. Full article

All-solid-state lithium batteries (ASSLBs) are emerging as a promising alternative to conventional lithium-ion batteries, offering solutions to challenges related to energy density and safety. Their core advancement relies on breakthroughs in solid-state electrolytes (SEs). SEs can be broadly grouped into two main types: inorganic solid electrolytes (ISEs) and organic solid electrolytes (OSEs). ISEs offer high ionic conductivity (0.1~1 mS cm⁻¹), a lithium-ion transference number close to 1, and excellent thermal stability, but their intrinsic brittleness leads to poor interfacial wettability and processing difficulties, limiting practical applications. In contrast, OSEs exhibit good flexibility and interfacial compatibility but suffer from poor ionic conductivity (10⁻⁴~10⁻² mS cm⁻¹) due to high crystallinity at room temperature, in addition to poor thermal stability and weak mechanical integrity, making it difficult to match high-voltage cathodes and suppress lithium dendrite growth. Against this backdrop, the stability of the organic–inorganic interface plays a crucial role. However, challenges such as low overall conductivity and unstable interfaces still limit their performance. This review provides a microscopic perspective on lithium-ion transport pathways across the polymer phase, the inorganic filler phase, and their interfacial regions. It categorizes inert fillers and active fillers, analyzing their structure–performance relationships and emphasizing the synergistic effects of filler dimensionality, surface chemistry, and interfacial interactions. In addition, cutting-edge analytical methods such as time-of-flight secondary ion mass spectrometry (TOF-SIMS) and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) have also been employed and are summarized into their roles for revealing the microstructures and dynamic interfacial behaviors of OICSEs. Finally, future directions are proposed, such as hierarchical pore structure design, surface functionalization, and simulation-guided optimization, aiming to provide theoretical insights and technological strategies for the development of high-performance composite electrolytes for ASSLBs. Full article

Background: The addition of chlorhexidine in dental restorative materials is a promising strategy to reduce the recurrence of tooth decay lesions. However, the main challenge is to develop materials with antimicrobial activity in the long term. Objective: This study analyses the effect of filler type and concentration of resin composites supplemented with chlorhexidine loaded in carrier montmorillonite particles (MMT/CHX) regarding their chemical, physical, and short- and long-term antimicrobial proprieties. Materials: Experimental composites were synthesized with 0, 30, or 60% filler in two ratios, 70/30 and 80/20, of barium glass/colloidal silica, respectively, and 5 wt% MMT/CHX. Conversion was measured using near Fourier-transform infrared spectrometry. Sorption and solubility were determined by specimen weight before and after drying and immersing in water. Flexural strength (FS) and elastic modulus (E) were determined by three bending tests using a universal test machine. Chlorhexidine release was monitored for 50 days. Streptococcus mutans UA159 was used in all microbiological assays. Inhibition halo assay was performed for 12 months and, also, biofilm growth for the specimens and colony-forming unit (CFU). Remineralization assay was used on restored teeth using measurements of microhardness Knoop and CFUs. Results: Conversion, sorption, and solubility were not affected by filler type and concentration. FS and E increase with the filler concentration, independent from filler type. Chlorhexidine was significantly released for 15 days for all experimental materials, and the increase in filler concentration decreased its release. Halo inhibition was observed for a longer time (12 months) in materials with 60 wt% filler at 70/30 proportion. Also, 60 wt% filler materials, independent from the filler ratio, reduced the CFU in relation to the control group from 8 to 12 months. In the remineralization assay, besides the absence of differences in hardness among the groups, after biofilm growth, the CFU was also significantly lower in materials with 60 wt% filler. Conclusions: Materials with 60% filler, preferentially with 70% barium glass and 30% silica, and 5% MMT/CHX particles demonstrated long-term antimicrobial activity, reaching 12 months of effectiveness. Also, this formulation was associated with higher mechanical properties and similar conversion, sorption, and solubility compared to the other materials. Full article

The growing demand for sustainable and multifunctional construction materials, particularly those capable of addressing durability and energy challenges, has motivated the development of conductive and photothermally active geopolymers. This study investigated the use of an Fe-rich spinel aggregate (FSA) as a high-density filler in geopolymers composed of ground granulated blast furnace slag and bauxite residue, with a fixed addition of 1 wt% graphite (binder-based) to enhance electrical conductivity. The effects of different FSA replacement percentages (0–100%) on compressive strength, electrical conductivity, photothermal efficiency, and chemical resistance were evaluated. An increase in the FSA content translated to an increase in the final compressive strength, with 100% FSA replacement achieving the highest value of 45.5 ± 2.5 MPa at 28 days. As the FSA content increased, the electrical resistivity decreased to as low as 42 Ω·m at 100% replacement. Under simulated solar flux conditions (1 kW/m²), photothermal analysis revealed that the 100% FSA mixtures exhibited the highest surface temperature increase of 9.8 °C after 300 s, indicating their superior thermal responsiveness. Furthermore, acid immersion in 10% HCl for 28 days showed mass gain in all geopolymers, with the highest gain observed at 50% FSA (+11.51%). Similarly, the strength increased after acid exposure up to a 75% FSA content. These findings highlight the multifunctional potential of FSA-enhanced geopolymers for high-mechanical-performance, electrically conductive, photothermally active, and chemically durable materials as multifunctional construction materials. Full article

A novel structure–functional-integrated particle featuring dual micromechanical interlocking property with resin matrix was constructed through surface modification of urchin-like serried hydroxyapatite (UHA) in this work, and the effect of this modification strategy on physicochemical and biological properties of dental resin composite was also investigated. A porous silica coating layer was anchored onto UHA surface via a simple template method in an oil−water biphase reaction system, and the coating time had a prominent effect on the coating thickness and morphology-structure of the particle. When these particles with different porous silica coating thickness were used as fillers for dental resin composite, results showed that UHA/PS5 (porous silica coating reaction time: 5 h) exhibited the optimal 3D urchin-like structure and a desirable porous silica coating thickness. Additionally, UHA/PS5 formed the best dual physical micromechanical interlocking structure when mixing with resin matrix, making the dental resin composites presented the desirable matrix/filler interfacial bonding, and the excellent physicochemical–biological properties, especially for flexural strength and water sorption-solubility. In vitro remineralization and cellular biological properties confirmed that the coating layer did not compromise their remineralization activity. The use of UHA/PSx provides a promising approach to develop strong, durable, and biocompatible DRCs. Full article

In this study, we present a novel and straightforward approach for the synthesis of copolymers and nanocomposites based on α- and β-pinene, employing an eco-friendly and cost-effective nano-reinforcing filler. The copolymers (α-co-β-P) were produced through cationic copolymerization, using AlCl₃ as a catalyst. The structural characterization of the resulting copolymer was validated through FT-IR, ¹H-NMR spectroscopy, and differential scanning calorimetry (DSC). The molecular weight of the obtained polymer is determined by Gel Permeation Chromatography (GPC) analysis and is about 4500 g/mol. Nanocomposites (α-co-β-P/Clay 2, 5, 8, and 10% by weight of nano-clay) were synthesized by combining clay and α-co-β-P copolymer in solution using ultrasonic irradiation. This ultrasound-assisted method was employed to enhance and assess the structural, morphological, and thermal properties of the pure copolymer. The morphology of the resultant nanocomposites was characterized using infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Thermogravimetric analysis (TGA) revealed that the nanocomposites exhibit a higher degradation temperature compared to the pure copolymer. The analyses provided evidence of the chemical modification of nano-clay layers and their uniform dispersion in the α-co-β-P copolymer matrix. Exfoliated structures were achieved for lower clay concentration (2% by weight), while intercalated structures and immiscible regions were observed for higher clay concentrations (5, 8, and 10% by weight). The antioxidant activity of α-pinene, β-pinene, and the obtained nanocomposites were studied using DPPH (2,2-diphenyl-1-picrylhydrazyl) as a model free-radical. The results demonstrate a significant antioxidant potential of the nanocomposites, showcasing their ability to effectively neutralize free-radicals. Finally, a novel procedure was devised for the rapid synthesis of copolymers and nanocomposites using α- and β-pinene. Full article