Search Results (434)

Background/Objectives: Research on noble metal nanoparticles (NPs) has increased over the past three decades, with advancements in synthesis techniques refining their physicochemical characteristics, including size, shape, and surface chemistry. Bimetallic NPs (BNPs) offer synergistic properties contributed by both metals. Gold (Au) and palladium (Pd) NPs possess low toxicity, high biocompatibility and loading, ease of synthesis and surface modification. Doxorubicin (DOX) and 5-fluorouracil (5-FU) are potent chemotherapeutic drugs but are rapidly metabolised in the body, producing severe side effects, limiting their use. Hence, innovative strategies to mitigate this is needed. Methods: In this study, AuPd NPs in a core-shell formation were chemically synthesized. The AuPd NPs were conjugated to 5-FU and DOX-encapsulated CS complexes and decorated with the targeting moiety transferrin (Tf). Results: Transmission electron microscopy and nanoparticle tracking analysis confirmed that the BNPs were spherical, with an average size of 73.4 nm. Functionalized BNPs were able to encapsulate more than 70% of 5-FU and DOX, resulting in a controlled drug release profile at pH 4.2. Cytotoxicity levels in human cancer cells, HeLa (cervical carcinoma) and MCF-7 (breast adenocarcinoma), as well as in non-cancer HEK293 (embryonic kidney) cells, revealed that the Tf-targeted nanocomplexes were HeLa cell-specific, with no significant cytotoxicity in the HEK293 cells. Tf-mediated cellular uptake was confirmed by receptor competition studies in the HeLa cells. Apoptosis and oxidative stress analysis confirmed cell death by apoptosis, consistent with the action of 5-FU and DOX. Conclusions: This study highlighted the potential of this BNP-nanocomplex as a suitable vehicle for drug delivery. Full article

Alginate [ALG] and chitosan [CS] are biomaterials of importance in drug-delivery because of their ability to form ionically-crosslinked nanosystems and polyelectrolyte-complexes under mild conditions. Here, a modified ionic-polyelectrolyte-pre-gelation method, with a controlled addition of reagents and sonication throughout the process, is reported to produce ALG¬¬-CS-based NPs. A mathematical study of the effects of the factors with influence in the process on the properties of NPs has been performed using a two-phase-design-of-experiment-based procedure, something never done to our knowledge. The concentration of ALG, CS and CaCl₂ and the ratio ALG:CS have significant influence on polydispersity (PDI), surface-charge (ZP) and encapsulation efficiency (EE%) of NPs. Moreover, CS flow rate has a significant effect over PDI and EE%. Thus, the values of ALG, CS and CaCl₂ concentration (mg/mL), ALG:CS (mL:mL) and CS flow rate (mL/min) to obtain the minimum-expected PDI (0.168) or the optimized EE% (86.7) are {0.30, 0.79, 1.00, 2.50:1.00, 0.86} or {0.30, 1.00, 1.00, 2.50:1.00, 2.00}, with ALG:CaCl₂ (mL:mL) and CaCl₂ flow rate (mL/min) fixed at 2.50:0.31 and 1.25. Although most of the conditions yielded highly-negative particles (minimum-expected of −67.8 mV using 0.69, 0.30 and 0.13 mg/mL of ALG, CS and CaCl₂ and ALG:CS of 2.50:0.59 mL:mL), varying the mass ratio of ALG:CS allowed for the generation of positively-charged particles (up to +21.1 mV with 0.30, 1.00 and 0.61 mg/mL of ALG, CS and CaCl₂ and ALG:CS of 2.50:1.00 mL:mL). In both cases, ALG:CaCl₂ (mL:mL), CaCl₂ and CS flow rates (mL/min) were fixed at 2.50:0.31, 1.25 and 1.25. The model for the NPs size depends only on CS and CaCl₂ concentrations, with the minimum- or maximum-expected (160 or 635 nm) at 0.30 and 1.00 or 1.00 and 0.30 of CS and CaCl₂, although the method allows a wide range of sizes (144.0–1965.0 nm). Full article

Background/Objective: Emerging evidence indicates that temporomandibular disorders (TMD) patients may present features of nociplastic pain (NP), characterized by central sensitization (CS)-related symptoms. This study aims to identify factors associated with CS-related symptoms and pain sensitivity in patients with TMD and NP-related features. Methods: In this cross-sectional study, 43 TMD patients were assessed for CS-related symptoms (CSI), proximal, distal, global pressure pain threshold (PPTs, algometer), orofacial pain intensity (VAS), jaw impairment (FAI), maximal isometric strength of four muscle groups (dynamometer), resting heart rate (RHR, chest band), kinesiophobia (TKS-11), physical activity level (IPAQ), anxiety (HADS), and sleep quality (PSQI). Associations were analyzed using linear regression models adjusted for gender, age, and symptoms duration. Results: Multivariate analysis showed that higher CSI was significantly associated with greater jaw impairment (Estimate 0.09, 95% CI 0.01 to 0.18) and higher pain intensity (Estimate 0.26, 95% CI 0.14 to 0.38). Lower PPT was significantly associated with lower grip strength (Proximal: Estimate 0.03, 95% CI 0.01 to 0.05; Distal: Estimate 0.07, 95% CI 0.01 to 0.14; Global: Estimate 2.44, 95% CI 0.57 to 4.31), and proximal PPT with higher RHR (Estimate −0.02, 95% CI −0.03 to 0). Conclusions: Association was found between CS-related symptoms and pain intensity and jaw impairment, while lower PPTs were related to decreased maximal isometric grip strength and elevated RHR, thus highlighting the need for multimodal treatment in TMD patients. Full article

Foot and mouth disease is a contagious viral disease infecting ungulates, with great economic impact on farmers’ income; it is primarily controlled using inactivated vaccines, which have certain limitations, such as short-lived immunity and a lack of mucosal immunity at the portals of virus entry. The present approach aims to exploit the efficiency of chitosan nanoparticle-encapsulated inactivated type ‘O’ FMDV antigen (FMDV-CS-NPs) to induce mucosal and systemic immune responses in a guinea pig animal model through intranasal and intramuscular administration in comparison with the conventional inactivated, mineral oil-adjuvanted vaccine that is administered systemically. In this study, the FMDV-CS-NPs were prepared by ionotropic gelation, followed by incubation; were characterized for their physical properties and in vitro antigen release; and were found to encapsulate a good amount of antigen. The prepared nanoparticles were assessed for their ability to induce humoral and cell-mediated immune responses by SNTs; indirect ELISAs for serum IgG, IgG1, and IgG2; and nasal washing sIgA and lymphocyte proliferation assays. The preparation induced comparatively more measurable sIgA and systemic immune responses with the intranasal and intramuscular routes of administration, respectively, which are attributable to a specific interaction between the positively charged chitosan and the negatively charged mucosal surface and cell membrane. The challenge infection protected 87.5% of the animals in the FMDV-CS-NP I/M group, followed by 77.7% in the FMDV-CS-NP I/N and inactivated vaccine groups. The outcomes of this study in guinea pigs highlight that chitosan nanoparticle-based vaccine formulations could be employed as a promising antigen delivery system for targeted delivery, devoid of any adverse effect, to induce protective immune responses. Full article

An electrochemical immunosensor was fabricated to identify CA15-3, a biomarker for breast cancer (BC). A composite sensor substrate made of “zeolitic imidazolate framework-8” (ZIF-8) and “reduced graphene oxide” (rGO) was chosen and its conductivity was further improved by the addition of chitosan (CS)-doped gold nanoparticles (AuNPs). The CS@AuNPs are able to conjugate with antibodies via the strong Au-S interaction, which offers multiple active sites for antibody immobilization and enhances the sensor performance. This immunosensor is capable of ultrasensitive detection of CA15-3 by specific antigen–antibody –interactions. In healthy people, normal serum CA15-3 is up to 25 U/mL. Under optimized experimental conditions, the alteration in the signal intensity measured by the sensor was related to the CA15-3 activity. The quantitative relationship was linear over 0.001–400 U/mL with a limit of detection (LOD) of 0.0031 U/mL at a “signal-to-noise ratio” (S/N) of 3 and a “correlation coefficient” (r²) of 0.9983. The developed immunosensor showed great accuracy, stability, and selectivity, and was able to detect CA15-3 in human serum samples. These results validate its potential as a reliable analytical platform for BC diagnosis and early clinical screening. Full article

Muscle gradually loses its regenerative capacity with aging. Recent evidence highlights age-related immune dysregulation as a key driver of satellite cell dysfunction and reduced muscle regeneration. Timely elimination of apoptotic cells by phagocytes through efferocytosis is essential for tissue repair. Therefore, exploring age-related alterations in the molecular machinery of efferocytosis and their impact on muscle regeneration is of great relevance. This study examined the efferocytic machinery in the gastrocnemius muscle tissue of young and aged rats after doxorubicin-induced acute myotoxicity and assessed the potential of Vitamin B12-loaded chitosan nanoparticles (B12 CS NPS) to enhance efferocytosis and promote skeletal muscle injury repair in aged rats. Aged rats exhibited impaired efferocytosis with a significant reduction in MerTK, PPARγ, and miR-124 expression, and increased ADAM17 expression. B12 CS NPS administration significantly improved efferocytosis and reduced necrotic tissue areas, accompanied by increased MerTK, PPARγ, and miR-124, and reduced ADAM17 expression. Supplementation with B12 CS NPS significantly enhanced satellite cell proliferation and differentiation, which was indicated by upregulated expression of Pax7, Myog, and MyoD. These findings reveal that age-related alterations in regulatory molecules impair efferocytosis in aged muscle and demonstrate the potential of B12 CS NPs to enhance efferocytosis and improve skeletal muscle repair. Full article

The aviation industry needs to develop sustainable, fire-safe cabin interior materials. Although wood is eco-friendly, its high flammability makes it challenging to meet flame retardant standards. Enhancing wood fire safety requires the creation of an environmentally friendly and flame retardant coating. In this study, a new type of intumescent flame retardant (IFR) coating was applied to the wood surface using the layer-by-layer (LBL) technique, with fully bio-based chitosan (CS), agar, and phytic acid (PA) as key components. The coated wood demonstrated improved durability, flame resistance, and thermal stability. Particularly, the Wood-2 sample achieved a vertical burning test (UL-94) V-0 rate and a limiting oxygen index (LOI) of 53.1%, which exceeded most previous reported flame retardant coatings. Cone calorimeter test and infrared thermography analysis confirmed that a thick layer of intumescent char formed when the coating was exposed to heat, effectively hindering heat transfer and oxygen supply. This flame retardant effect is attributed to a synergistic mechanism involving nitrogen/phosphorus (N/P) elements. This study offers an environmentally friendly solution for wood flame retardancy and lays an experimental and theoretical foundation for the development of green aviation interior materials. Full article

Background: Multidrug-resistant (MDR) pulmonary infections represent a critical global health challenge, necessitating innovative therapeutic approaches. Green synthesis methodologies offer sustainable alternatives for nanoparticle fabrication while addressing antimicrobial resistance. Methods: Stimuli-responsive chitosan–silver hybrid nanoparticles (CS–Ag HNPs) were biosynthesized using Pseudomonas fluorescens bacterial extracts and loaded with ciprofloxacin for targeted pulmonary delivery. Comprehensive characterization included dynamic light scattering, transmission electron microscopy, UV–visible spectroscopy, and aerodynamic assessment via next-generation impactor. Antimicrobial efficacy was evaluated against MDR Pseudomonas aeruginosa and Klebsiella pneumoniae, including biofilm disruption studies, and biocompatibility was assessed. Molecular docking analysis elucidated binding mechanisms. Cytotoxicity and epithelial barrier integrity were evaluated using Calu-3 cell models. Results: The biosynthesized NPs exhibited optimal physicochemical properties (180 ± 20 nm, PDI 0.21 ± 0.04, ζ-potential + 32.4 ± 3.1 mV) with high encapsulation efficiency (68.2 ± 4.0%). Aerodynamic analysis revealed excellent inhalation characteristics (MMAD 2.6 μm, FPF 65 ± 5%). The hybrid system demonstrated 4-fold enhanced antimicrobial activity against MDR pathogens and significant biofilm disruption (70% for P. aeruginosa, 65% for K. pneumoniae) compared to free ciprofloxacin. Cell viability remained ≥85% at therapeutic concentrations. Molecular docking revealed enhanced drug-target binding affinity (−11.2 vs. −9.3 kcal/mol) and multi-residue interactions. Conclusions: Green-synthesized CS–Ag HNPs represent a promising sustainable platform for combating pulmonary MDR infections through enhanced antimicrobial efficacy and optimal aerodynamic properties. Full article

Background: Mesenchymal stem cells (MSCs) have shown positive therapeutic effects on various diseases; however, their functionality can decline during in vitro expansion. Selenium (Se) supplementation has emerged as a strategy for enhancing MSC culture. This study evaluated the effects of different forms of selenium (Na₂SeO₄, SeMet, ebselen, and chitosan-coated selenium nanoparticles (CS-SeNPs)) on the biological functions of MSCs. Methods: Human umbilical cord-derived MSCs (HUC-MSCs) were cultured in media supplemented with various selenium compounds at specific concentrations. To investigate their biological effects, we assessed cell proliferation, morphology, surface marker expression, and differentiation potential. Furthermore, to elucidate the underlying mechanisms, we analyzed key markers of cellular senescence, including p16, p21, IL-6, IL-8, p27, p53, and reactive oxygen species (ROS) levels. Results: All the selenium treatments promoted hUC-MSC proliferation at specific concentrations. CS-SeNPs and Na₂SeO₄ exhibited relatively high bioavailability, whereas ebselen and SeMet demonstrated relatively low toxicity. The optimal concentration (0.5 μM CS-SeNPs or 0.25 μM Na₂SeO₄) significantly enhanced proliferation without altering the hUC-MSC morphology, phenotype, or differentiation capacity. Both CS-SeNPs and Na₂SeO₄ effectively promoted hUC-MSC proliferation and reduced the senescence of hUC-MSCs by downregulating key senescence-related effectors: the cell cycle inhibitors p16, p21, p27, and p53; and the levels of ROS and senescence-associated secretory phenotype factors (IL-6 and IL-8). Conclusions: Selenium supplementation is an effective strategy for improving MSC expansion and alleviating senescence. The beneficial effects are dependent on the specific selenium compound used, with CS-SeNPs and Na₂SeO₄ showing particularly strong potential for enhancing the bioavailability and function of hUC-MSCs during in vitro cultivation. Full article

The main objective of treatment with MSZ is to ensure that the drug reaches the colon, where it exerts its therapeutic effect. However, due to pH variation throughout the gastrointestinal tract and the risk of degradation or premature absorption, a considerable portion of the drug may not reach the colon in adequate concentrations. In this study, computational modeling was combined with experimental approaches for the design of MSZ nanoparticles (MSZ-NPs) suitable for chitosan (CS) incorporation. Quantum chemical calculations and molecular modeling revealed the importance of pH as a nucleation determinant and in the growth of the MSZ complexes. At pH~1.0, cationic clusters predominated, characterized by higher interaction energies and larger volumes/surface areas. At pH~4.0, zwitterionic clusters were stabilized, whereas at pH~6.0, anionic clusters formed the most compact assemblies, with the smallest calculated volume (4817 ų) and surface area (2458 Ų). Consistent with the computational predictions, experimental approaches showed a progressive reduction in particle size with increasing pH. Nanoparticles prepared at pH 1.5 (F1.5), 4.0 (F4.0), and 6.0 (F6.0) showed mean diameters of 937, 556, and 146 nm, respectively, with corresponding zeta potentials (ZPs) of +8.5, −22.3, and −31.6 mV. Drug precipitation efficiency was as follows: 51.6% to F1.5, 95.1% to F4.0, and 75.5% to F6.0. F4.0 and F6.0 were selected to evaluate the effect of CS incorporation. The CS incorporation resulted in a reversal in the zeta potential in formulations prepared at pH 4.0 and 6.0. When 5% CS was added during nanoparticle formation (F4.0-5 and F6.0-5), the particles were smaller in diameter and had a lower positive ZP. F6.0-5 achieved the most favorable properties and strong mucoadhesion, evidenced by the ZP shift from +26.8 mV to −1.9 mV at a pH of 6.8. The modeling and experimental approaches guided the rational design of MSZ-NPs for CS incorporation, yielding mucoadhesive nanoparticles for colon-targeted drug delivery. Full article

Proteus mirabilis (P. mirabilis) serves as a multi-host–pathogen regarded as an alarming foodborne infectious disease, causing illnesses of variable severity in both livestock and human beings. The present study aimed to estimate the prevalence, antibiotic susceptibility profiles, and associated antimicrobial resistance genes (ARGs) of P. mirabilis isolates obtained from diseased broiler chickens and native Egyptian buffaloes in Kafr El-Sheikh and Dakahlia governorates, Egypt. In addition, this study investigated the antibacterial activity of chitosan (CS) and chitosan nanoparticles (CSNPs), including the estimation of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of CS at concentrations of 1% and 2%, as well as CSNPs. Furthermore, the sub-MIC values were utilized to assess the inhibitory effects of CS and CSNPs on swarming motility. P. mirabilis was detected in 68% (34/50) of broiler chickens and 40.74% (11/27) of buffaloes. Interestingly, all P. mirabilis isolates were tested against 21 antimicrobial drugs and showed high resistance against either critical, highly important, or important antimicrobial drugs. For chicken-originated P. mirabilis, 50% (17/34) of isolates were revealed to be extensively drug-resistant (XDR) and 50% (17/34) of isolates were revealed to be pan-drug-resistant (PDR). Meanwhile, 9.09% (1/11) of buffalo-originated P. mirabilis isolates were revealed to be XDR and 90.91% (10/11) of the isolates were revealed to be PDR. Among P. mirabilis isolates from broiler chickens, the prevalence of resistance genes was as follows: int1 (97.06%), dfrA1 (100%), sul2 (97.06%), catA1 (44.12%), aadA1 (97.06%), tet(M) (81.82%), ermB (23.53%), msrA (0%), qnrA (47.06%), qnrS (0%), gyrA (0%), mcr-1 (11.76%), bla_TEM (97.06%), bla_CTX-M (26.47%), bla_OXA-10 (2.94%), bla_CMY-2 (41.18%), and bla_SHV (0%). The corresponding detection rates in buffalo-derived isolates were 100%, 100%, 90.91%, 63.64%, 100%, 70.59%, 18.18%, 0%, 9.09%, 0%, 0%, 18.18%, 81.82%, 18.18%, 18.18%, 63.64%, and 0%, respectively. Carbapenemase genes were found in none of the isolates from either species. CSNPs demonstrated superior antibacterial and anti-virulence activity against resistant P. mirabilis. CSNPs exhibited significantly lower MIC (0.067–0.081 mg/mL) and MBC (0.167–0.177 mg/mL) values compared with conventional CS formulations (MIC: 3.25–4.5 mg/mL; MBC: 6.67–9.08 mg/mL) in both broiler and buffalo isolates. In inhibition zone assays, the CSNPs + ciprofloxacin (CIP) combination showed the highest efficacy with a 50–58% increase in the inhibition area. Both CSNPs and CS 2% substantially reduced swarming motility by 45–52%, with CSNPs showing the strongest inhibitory effect. These outcomes highlight how P. mirabilis carries and disseminates antibiotic resistance, presenting serious threats to health policy and livestock. Also, CS or CSNPs, either alone or enhanced with CIP, are effective in vitro against resistant P. mirabilis, which promotes the treatment of Proteus infections to guarantee a bactericidal impact. Full article

This paper proposes a cooperative framework for resource allocation in multi-access edge computing (MEC) under a partial task offloading setting, addressing the joint challenges of learning performance and system efficiency in heterogeneous edge environments. In the proposed architecture, selected users act as edge servers (SEs) that collaboratively assist others alongside a central server (CS). A joint optimization problem is formulated to integrate model training with resource allocation while accounting for data freshness and spatial correlation among user tasks. The correlation-aware formulation penalizes outdated and redundant data, leading to improved robustness against non-i.i.d. distributions. To solve the NP-hard problem efficiently, a projected gradient descent (PGD) method is developed. The simulation results demonstrate that the proposed cooperative approach achieves a balanced delay of $0.042$ s, close to edge-only computing ($0.033$ s) and $30\%$ lower than the CS-only mode, while improving clustering accuracy to $99.2\%$ (up to $15\%$ higher than the baseline). Moreover, it reduces the central server load by nearly half, ensuring scalability and latency compliance within 3GPP limits. These findings confirm that cooperation between SEs and the CS substantially enhances reliability and performance in distributed Edge-AI system. Full article

This study evaluated the impact of cotton (CO) and polyester (PES) fabric support modules on the filtering efficiency of chitosan/silver nanoparticles/graphene oxide (CS/AgNP/GO). The experimental results showed that both CO and PES fabrics may serve as excellent support modules for CS/AgNP/GO composite membranes, enhancing water permeability and greatly improving the filtration process. The effectiveness of the membrane separation process depends on how the molecules in the composite structure interact with the supporting components. Both fabric-supported modules improved the wettability of the membrane; however, the CO is more hydrophilic than the PES of roughly the same thickness. This was attributed to improved wettability and capillary pore diameters inside the molecular structure of the CO-supported membrane, in contrast to the PES-supported modified CS composite within the same timeframe, confirming a higher adhesive force resulting from heightened hydrophilicity. The improved chemical bonding between the CS composite and the support materials resulted in an increase in mechanical properties. The maximum tensile strength of 48.46 MPa was attained by the CO-supported composite, followed by the PES-supported modified CS filtration membrane (43.73 MPa), while the non-fabric-supported membrane exhibited the lowest tensile strength of 37.23 MPa with the highest elongation at break (64.2%). Full article

Chitosan nanoparticles (CSNPs), a product of nanotechnology, have emerged as promising biostimulants with significant applications in sustainable agriculture for enhancing crop yield and quality. In this study, the effects of foliar-applied CSNPs on yield and bioactive compounds in melon (Cucumis melo L.) fruits were evaluated. Five increasing concentrations of CSNPs (0, 0.2, 0.4, 0.6, and 0.8 mg mL⁻¹) were foliarly applied. The foliar spraying of CSNPs exerted positive effects on fruit productivity and nutraceutical attributes. The most significant yield and commercial quality were achieved with the 0.4 mg mL⁻¹ dose. In contrast, the 0.8 mg mL⁻¹ dose was most effective in enhancing optimal postharvest characteristics, including fruit firmness and reduced weight loss, as well as stimulating the accumulation of bioactive compounds (such as flavonoids and vitamin C) and antioxidant capacity. In the case of phenols, the highest total phenolic content was observed at concentrations of 0.6 and 0.8 mg mL⁻¹. Therefore, the foliar application of CSNPs constitutes a versatile and sustainable strategy, allowing for the tailoring of application doses to either maximize yield or enhance the functional and postharvest quality of melon fruits. Full article

This study investigated the functionality and antifouling capabilities of the chitosan–silver nanoparticle–graphene oxide (CS/AgNPs/GO) composite membrane. An increase in the molecular interaction between the membrane surface and bovine serum albumin solution enhanced the flow recovery rate (FRR) due to the presence of amide -NH₂ and -OH groups. The modified CS composite showed a strong ability to prevent fouling, achieving over 77.5% due to greater interfacial intermolecular bonding. In addition, the tensile strength of the membrane composite improved from 42.7 to 49.6 MPa with an increase in the concentration of dimethylacetamide employed as a plasticizer. Therefore, efficient molecular interactions within the polymer matrix would significantly influence the membrane’s flux recovery rate, tensile strength, and ability to prevent fouling. Full article