Search Results (231)

Background/Objectives: Magnetic iron oxide nanoparticles (IONPs), human serum albumin (HSA) and folic acid (FA) are prospective components for hybrid nanosystems for various biomedical applications. The magnetic nanosystems FA-HSA@IONPs (FAMs) containing IONPs, HSA, and FA residue are engineered in the study. Methods: Composition, stability and integrity of the coating, and peroxidase-like activity of FAMs are characterized using UV/Vis spectrophotometry (colorimetric test using o-phenylenediamine (OPD), Bradford protein assay, etc.), spectrofluorimetry, dynamic light scattering (DLS) and electron magnetic resonance (EMR). The selectivity of the FAMs accumulation in cancer cells is analyzed using flow cytometry and confocal laser scanning microscopy. Results: FAMs (d_N~55 nm by DLS) as a drug delivery platform have been administered to cancer cells (human breast adenocarcinoma MCF-7 and MDA-MB-231 cell lines) in vitro. Methylene blue, as a model photosensitizer, has been non-covalently bound to FAMs. An increase in photoinduced cytotoxicity has been found upon excitation of the photosensitizer bound to the coating of FAMs compared to the single photosensitizer at equivalent concentrations. The suitability of the nanosystems for photodynamic therapy has been confirmed. Conclusions: FAMs are able to effectively enter cells with increased folate receptor expression and thus allow antitumor photosensitizers to be delivered to cells without any loss of their in vitro photodynamic efficiency. Therapeutic and diagnostic applications of FAMs in oncology are discussed. Full article

The recent COVID-19 pandemic has made the public aware of the importance of combating pathogenic microorganisms before they enter the human body. This growing threat from microorganisms prompted us to conduct research into a new type of coating that would be an alternative to the continuous disinfection of touch surfaces. Our goal was to design, synthesise and thoroughly characterise such a coating. In this work, we present a nanocomposite material composed of a thin-layer mesoporous SBA-15 silica matrix containing copper phosphonate groups, which act as catalytic centres responsible for the generation of reactive oxygen species (ROS). In order to verify the structure of the material, including its molecular structure, microscopic observations and Raman spectroscopy were performed. The generation of ROS was confirmed by fluorescence microscopy analysis using a fluorogenic probe. The antimicrobial activity was tested against a wide spectrum of Gram-positive and Gram-negative bacteria, while cytotoxicity was tested on BALB/c3T3 mouse fibroblast cells and HeLa cells. The studies fully confirmed the expected structure of the obtained material, its antimicrobial activity, and the absence of cytotoxicity towards fibroblast cells. The results obtained confirmed the high application potential of the tested nanocomposite coating. Full article

Background/Objectives: Mycophenolate mofetil (MMF) has emerged as a valuable immunosuppressive agent used in the management of oral mucocutaneous diseases, particularly in autoimmune and inflammatory conditions, such as pemphigus vulgaris (PV), oral lichen planus (OLP), mucous membrane pemphigoid (MMP), systemic lupus erythematosus (SLE), erythema multiforme (EM) and recurrent aphthous stomatitis (RAS). This review consolidates the current evidence regarding MMF’s efficacy, safety and clinical applications across these conditions. Methods: A comprehensive review of literature was performed, focusing on the mechanism of action, dosing strategies, therapeutic outcomes and adverse effects associated with MMF therapy in oral mucocutaneous diseases. The potential of therapeutic drug monitoring (TDM) in optimizing MMF therapy and minimizing adverse effects was also explored. Results: The review demonstrates that MMF is effective in inducing disease remission in up to 80% of patients with PV, with notable steroid-sparing effects. In OLP, MMF provided significant clinical improvement, especially in patients with severe and refractory forms of the disease. For MMP, MMF showed an 89% response rate, particularly when combined with corticosteroids, though gastrointestinal side effects were noted in some patients. In SLE, MMF was effective in managing both renal and non-renal manifestations, with favorable remission rates observed in patients receiving MMF therapy. For EM, MMF’s effectiveness was limited, with only a small number of patients responding to therapy. In RAS, there is limited evidence of MMF’s efficacy, with only partial improvement in severe cases reported. MMF is a promising immunomodulatory therapy for oral mucocutaneous diseases, particularly in reducing corticosteroid dependence and improving patient outcomes. However, the variability in the study designs, dosages and patient populations complicates the generalization of these findings. Conclusions: There is a pressing need for randomized controlled trials to validate MMF’s efficacy and long-term safety across all disease categories. The integration of therapeutic drug monitoring (TDM) shows potential for improving disease control and minimizing adverse effects, making it a key consideration for future research. Full article

Background: Physiologically based biopharmaceutics modeling (PBBM) models can help to predict drug release and in vivo absorption behaviors. Colon drug delivery systems have gained interest over the past few years due to the advantages they provide in treating certain diseases in a local way. The objectives of this work were to simulate the biopharmaceutical and pharmacokinetic behavior of metronidazole hydrophilic matrices coated with different enteric polymers and to highlight the factors with a significant impact on the simulated pharmacokinetic parameters. Methods: Physicochemical properties of metronidazole were introduced into Simcyp^® simulator platform, and the Advanced Dissolution Absorption Model (ADAM) was employed to simulate the in vivo intestinal absorption and colonic concentrations of metronidazole using a PBBM model. A Kruskal–Wallis test was carried out in order to determine which one of the factors studied has a statistically significant impact on the pharmacokinetic parameters (AUC, C_max, and T_max) simulated. Results: Enteric-coated matrix tablets are capable of avoiding metronidazole absorption in the small intestine and releasing it in the colonic region. The release and absorption rates of metronidazole depend largely on the percentage of weight gain of the coating and also on the coating agent. Coated tablets with a time-dependent coating show less variability. Conclusions: PBBM models can help predict the release from drug delivery systems and the pharmacokinetics in vivo of metronidazole from data obtained in vitro, although complementary in vivo studies should be needed. Full article

The Wan’an Bridge, the longest wooden lounge bridge in China with a history of more than 900 years, was devastated by a catastrophic fire in 2022. This tragic event underscores the susceptibility of historical wooden structures to fire damage. In this article, the bridge’s intricate structure and the development of the fire incident are introduced in detail. To gain a deeper insight into the patterns of fire propagation across the bridge and assess the reliability of fire simulations in predicting fire spread in historical wooden structures, we utilized the Fire Dynamics Simulator (FDS), with a sophisticated pyrolysis model and thermal response parameters specifically tailored to ancient fir wood. The modeling results reveal that the FDS simulation reflects the actual fire spread process well. Both the investigation and simulation findings indicate that once the flame reaches above the bridge deck, it enters a rapid three-dimensional propagation phase that is exceptionally challenging to control. Furthermore, the modeling results suggest that the application of intumescent fire-retardant coatings can significantly delay fire spread, reduce heat release rates, and suppress smoke production, thereby making them an effective fire prevention measure for historical wooden buildings. Full article

Clostridioides difficile (C. difficile) is a major pathogen responsible for antibiotic-associated diarrhea, frequently observed in hospital settings. Due to the widespread use of antibiotics, the incidence and severity of C. difficile infection (CDI) are rising across the world. CDI is primarily driven by two homologous protein exotoxins, toxin A (TcdA) and toxin B (TcdB). Other putative virulence factors include binary toxin CDT, surface layer proteins, phosphorylated polysaccharides, and spore coat proteins. These C. difficile virulence factors are potential targets for vaccine development. Although several C. difficile vaccines have entered clinical trials, there is currently no approved vaccine on the market. This review outlines the intoxication mechanism during CDI, emphasizing the potential antigens that can be used for vaccine development. We aim to provide a comprehensive overview of the current status of research and development of C. difficile vaccines. Full article

Background/Objectives: This study aimed to evaluate the degradation of omeprazole suspension under various pH conditions and to propose recommendations for preparing compounded suspensions. Given the clinical need for alternative dosage forms for pediatric and geriatric patients and those with dysphagia, the research focused on assessing whether modifications in formulation composition—specifically the inclusion of sodium bicarbonate—could improve omeprazole stability, thus enhancing its bioavailability. Methods: Three formulations were prepared: O1, based on crushed enteric-coated pellets from a commercial product; O2, with crushed pellets suspended in an 8% sodium bicarbonate solution with glycerin; and O3, with pure omeprazole suspended in an 8% sodium bicarbonate solution with glycerin. Release studies were conducted using basket or paddle apparatus under conditions simulating fasted (pH 1.2 and 6.8) and fed (pH 6, 4.5, and 3) gastric and intestinal juices at 37 °C over 120 min. At predetermined intervals, samples were withdrawn and analyzed by a validated HPLC method with UV detection to quantify the released omeprazole. Results: The commercial enteric-coated product showed no release at a low pH, confirming its protective coating. In contrast, formulation exhibited significant degradation in acidic environments. The O2 formulation, benefiting from the buffering effect of sodium bicarbonate, showed improved stability compared to O1. Notably, formulation O3 yielded the highest drug recovery, with approximately 74% released at pH 6 and 65% at pH 6.8, demonstrating significantly better performance, as confirmed by statistical analysis (p < 0.05). Conclusions: The composition of omeprazole suspensions substantially influences the drug stability and release profiles. The O3 formulation, based on pure omeprazole with sodium bicarbonate, is recommended for immediate-release suspensions to enhance bioavailability. Further studies are needed to optimize conditions for pediatric use. Full article

Over the past few decades, peanut smut, caused by Thecaphora frezzii, has evolved from an emerging disease to a major global threat to peanut production. However, critical knowledge gaps persist regarding the anatomical pathways and host responses involved in infection, colonization, and sporulation. This study examines the pathosystem and histopathology of the biotrophic phase of T. frezzii in the susceptible cv. Granoleico. Anatomical analyses were conducted using light microscopy, confocal laser scanning, and scanning electron microscopy. Our findings reveal that T. frezzii enters the host through the peg rather than the ovary tip, invading during the R2-subterranean phase. Fruit colonization occurs at the R3-stage when the mechanical layer between the mesocarp and endocarp has not yet formed. Hyphal entry into the seed takes place between the R3-medium and R3-late pod stages via the funiculus, leading to extensive seed coat colonization without penetrating the embryo. Once inside, hyperplasia and hypertrophy are triggered, coinciding with teliospore formation. Teliosporogenesis disrupts nutrient translocation, arresting embryo development. The hyphae colonize tissues intracellularly, utilizing living cells of the vascular bundles and following the peanut’s photoassimilate transport pathway. Investigating these structural responses in phenotypically contrasting peanut genotypes may provide key insights into the anatomical barriers and defense mechanisms that determine disease susceptibility and resistance, ultimately contributing to the development of resistant cultivars. Full article

Background: Agarwood has been widely used for the treatment of gastrointestinal diseases. Our research group has suggested that agarwood alcohol extracts (AAEs) provide good gastric mucosal protection. However, the exact mechanisms underlying this effect remain unclear. Objectives: This study aimed to investigate the ameliorative effect of agarwood chromone on gastric ulcers and its mechanism. Methods: Network pharmacology was used to predict the disease spectrum and key therapeutic targets of 2-(2-phenylethyl)chromone (CHR1) and 2-(2-(4-methoxyphenyI)ethyl)chromone (CHR2). Mice were orally administered CHR1 (20 and 40 mg/kg) and CHR2 (20 and 40 mg/kg) and the positive drug omeprazole as an enteric-coated capsule (OEC, 40 mg/kg) orally. After 7 days of pretreatment with the CHRs, gastric ulcers were induced using absolute ethanol (0.15 mL/10 g). The ulcer index, gastric histopathology, biochemical parameters, and inflammatory and apoptotic proteins were evaluated. Finally, binding of the core compounds to the key targets was verified via molecular docking and visualized. Results: The pharmacological results show that the CHRs reduced the gastric occurrence and ulcer inhibition rates by up to more than 70% in a dose-dependent manner. The CHRs decreased the levels of interleukin 6 (IL-6), interleukin 12 (IL-12), interleukin 18 (IL-18), and tumor necrosis factor α (TNF-α), and improved the severity of the pathological lesions in the gastric tissue. The expression of ATP-binding box transporter B1 (ABCB1), arachidonic acid-5-lipoxygenase (ALOX5), nuclear factor kappa B (NF-κB), cysteinyl aspartate specific proteinase 3 3 (Caspase3), and cysteinyl aspartate specific proteinase 9 (Caspase9) was inhibited, but the expression of B-cell lymphoma-2 (Bcl-2) was enhanced. The CHRs bound stably to the key targets via hydrogen bonding, van der Waals forces, etc. These results demonstrate that agarwood chromone compounds exert alleviative effects against the occurrence and development of gastric ulcers by inhibiting the NF-κB and caspase pathways. The CHRs have a therapeutic effect on gastric ulcers through anti-inflammation and anti-apoptosis mechanisms. Conclusions: This study suggests that agarwood may have a potential role in drug development and the prevention and treatment of gastrointestinal inflammation, and tumors. Full article

TiAlSiN and AlCrN coatings are two representative coatings with excellent properties in TiN-based and CrN-based coatings, respectively. Multilayering is one of the most important directions for coating performance optimization. In this paper, nanoscale monolayer TiAlSiN, AlCrN, and multilayer TiAlSiN/AlCrN coatings were prepared. The microstructure, mechanical properties, oxidation resistance, and wear resistance of the above three coatings were investigated. The following properties of the TiAlSiN/AlCrN coating, including phase, nanohardness, elastic modulus, adhesion strength, and oxidation resistance, fall between those of the TiAlSiN and AlCrN coatings and conform to the “law of mixtures”. Due to the interfacial effect of the multilayer coating, the residual stress of the TiAlSiN/AlCrN coating is less than that of the two monolayer coatings. At 500 °C, the order of wear resistance of the three coatings is consistent with the order of H³/E*² values, i.e., TiAlSiN > TiAlSiN/AlCrN > AlCrN; at 800 °C, the order of wear resistance becomes TiAlSiN/AlCrN > TiAlSiN > AlCrN because TiAlSiN coating has entered the rapid oxidization stage first, reducing its wear resistance. Full article

Introduction. The rise of multidrug resistance in Gram-negative ESKAPE pathogens is a critical challenge for modern healthcare. Colistin (CT), a peptide antibiotic, remains a last-resort treatment for infections caused by these superbugs due to its potent activity against Gram-negative bacteria and the rarity of resistance. However, its clinical use is severely limited by high nephro- and neurotoxicity, low oral bioavailability, and other adverse effects. A promising strategy to improve the biopharmaceutical properties and safety profile of antibiotics is the development of biopolymer-based delivery systems, also known as nanoantibiotics. Objective. The aim of this study was to develop polyelectrolyte complexes (PECs) for the oral delivery of CT to overcome its major limitations, such as poor bioavailability and toxicity. Methods. PECs were formulated using chondroitin sulfate (CHS) and a cyanocobalamin–chitosan conjugate (CSB12). Vitamin B12 was incorporated as a targeting ligand to enhance intestinal permeability through receptor-mediated transport. The resulting complexes (CHS-CT-CSB12) were characterized for particle size, ζ-potential, encapsulation efficiency, and drug release profile under simulated gastrointestinal conditions (pH 1.6, 6.5, and 7.4). The antimicrobial activity of the encapsulated CT was evaluated in vitro against Pseudomonas aeruginosa. Results. The CHS-CT-CSB12 PECs exhibited a hydrodynamic diameter of 446 nm and a ζ-potential of +28.2 mV. The encapsulation efficiency of CT reached 100% at a drug loading of 200 µg/mg. In vitro release studies showed that approximately 70% of the drug was released within 1 h at pH 1.6 (simulating gastric conditions), while a cumulative CT release of 80% over 6 h was observed at pH 6.5 and 7.4 (simulating intestinal conditions). This release profile suggests the potential use of enteric-coated capsules or specific administration guidelines, such as taking the drug on an empty stomach with plenty of water. The antimicrobial activity of encapsulated CT against P. aeruginosa was comparable to that of the free drug, with a minimum inhibitory concentration of 1 µg/mL for both. The inclusion of vitamin B12 in the PECs significantly improved intestinal permeability, as evidenced by an apparent permeability coefficient (P_app) of 1.1 × 10⁻⁶ cm/s for CT. Discussion. The developed PECs offer several advantages over conventional CT formulations. The use of vitamin B12 as a targeting ligand enhances drug absorption across the intestinal barrier, potentially increasing oral bioavailability. In addition, the controlled release of CT in the intestinal environment reduces the risk of systemic toxicity, particularly nephro- and neurotoxicity. These findings highlight the potential of CHS-CT-CSB12 PECs as a nanotechnology-based platform for improving the delivery of CT and other challenging antibiotics. Conclusions. This study demonstrates the promising potential of CHS-CT-CSB12 PECs as an innovative oral delivery system for CT that addresses its major limitations and improves its therapeutic efficacy. Future work will focus on in vivo evaluation of the safety and efficacy of the system, as well as exploring its applicability for delivery of other antibiotics with similar challenges. Full article

The growing intensity and frequency of bushfires across the globe pose serious threats to building safety when it comes to the vulnerability of glass windows. During bushfires, extreme heat can cause significant damage to these windows, creating openings that allow embers, radiant heat, and flames to enter buildings. This study investigated the effectiveness of various construction materials, including thin steel sheets, glass fibre blankets, aluminium foil layers, and intumescent layers on glass fibre blankets, as bushfire-resistant shutters for protecting windows in bushfire-prone areas. The shutters were tested under two scenarios of radiant heat exposure: rapid and prolonged exposures of 11 and 47 min, respectively. Heat transfer models of the tested shutters were developed and validated using fire test results, and then comparisons of the performance of materials were made through parametric studies for bushfire radiant heat exposure. The results show that a 0.4 mm glass fibre blanket with aluminium foil performed best, with very low glass temperatures and ambient heat fluxes due to the reflective properties of the foil. Similarly, a thin steel sheet (1.2 mm) also effectively maintained low glass temperatures and ambient heat fluxes. Additionally, graphite-based intumescent coating on a glass fibre blanket reduced the ambient heat flux. These results highlight the importance of bushfire-resistant shutters and provide valuable insights for improving their design and performance. Full article

Background/Objectives: Omeprazole undergoes degradation in acidic conditions, which makes it unstable in low pHs found in the gastric environment. The vast majority of already marketed omeprazole formulations use enteric polymer coatings to protect the drug from exposure to acidic pH in the stomach, allowing for drug release in the small intestine where the pH is higher. This study aimed to explore the technical aspects of using stomach acid neutralizers as an alternative to polymeric coatings for omeprazole. Methods: After evaluating various neutralizers, magnesium oxide and sodium bicarbonate were chosen to be incorporated into capsules containing omeprazole, which then underwent in vitro dissolution testing to assess their ability to maintain optimal pH levels and ensure appropriate dissolution kinetics. Hygroscopicity and chemical stability of the selected formulation were tested to prove pharmaceutical quality of the product. An in vivo pharmacokinetic study was conducted to demonstrate the efficacy of the omeprazole–sodium bicarbonate formulation in providing faster absorption in humans. Results: Sodium bicarbonate was selected as the most suitable antacid for ensuring omeprazole stabilization. Its quantity was optimized to effectively neutralize stomach acid, facilitating the rapid release and absorption of omeprazole. In vitro studies demonstrated the ability of the formulation to neutralize gastric acid within five minutes. In vivo studies indicated that maximum concentrations of omeprazole were achieved within half an hour. The product met the requirements of pharmaceutical quality. Conclusions: An easily manufacturable, fast-absorbing oral formulation was developed as an alternative to enteric-coated omeprazole. Full article

Background/Objectives: Lactoferrin (Lf), a multifunctional iron-binding protein, has considerable potential for use as an active ingredient in food supplements due to its numerous positive effects on health. As Lf is prone to degradation, we aimed to develop a formulation that would ensure sufficient stability of Lf in the gastrointestinal tract and during product storage. Methods: A simple, efficient, and well-established technology that has potential for industrial production was used for the double-coating of neutral pellet cores with an Lf layer and a protective enteric coating. Results: The encapsulation efficiency was 85%, which is among the highest compared to other reported Lf formulations. The results of the dissolution tests performed indicated effective protection of Lf from gastric digestion. A comprehensive stability study showed that the stability was similar regardless of the neutral pellet core used, while a significant influence of temperature, moisture, product composition, and packaging on the stability of Lf were observed, and were therefore considered in the development of the final product. The experimentally determined shelf life is extended from 15 to almost 30 months if the product is stored in a refrigerator instead of at room temperature, which ensures the commercial applicability of the product. Conclusion: We successfully transferred a technology commonly used for small molecules to a protein-containing product, effectively protected it from the destructive effects of gastric juice, and achieved an acceptable shelf life. Full article

Grouting technology is an important method of ground reinforcement and can effectively improve the stability of engineering rock mass. During overburden isolated grouting in coal mines, the influence of unexpected fractures may lead to substantial grout leakage, resulting in ineffective grouting. The existing natural sedimentation sealing method is mainly applicable to small fractures and low grout flow, while the chemical-reagent rapid-sealing method can cause grouting channel blocking, making it less suitable for overburden isolated grouting. This paper proposes a “capsule” sealing method, detailing the preparation of the sealing material and evaluation of its properties through testing. The sealing material, prepared using the air suspension method, was coated with paraffin on a superabsorbent polymer (SAP) material, which has delayed expansion characteristics. Although this material does not expand within the grouting fractures of overburden rock, it expands rapidly upon entering the leakage channel, accumulating within the channel to achieve effective sealing. A simulation experimental system was designed to simulate the sealing of the slurry leakage channel, and the sealing characteristics were experimentally investigated. Under consistent particle size conditions, a higher film cover ratio led to a more pronounced delayed expansion effect and extended the time required for the sealing material to achieve its maximum expansion. When the content of sealing material with particle sizes of 20 mesh, 40 mesh, and 60 mesh, and a film ratio of 20% was 1.0%, the fractures below 4 mm were effectively sealed. When the fracture aperture is 4–6 mm, the sealing material with a covering ratio of 20% or 30% should have a minimum content of 1.5%, while the sealing material with a covering ratio of 50% should have a minimum content of 2.0%. The findings of this study outline an effective prevention and control method for the sealing of abnormal slurry leakage in overburden isolated grouting engineering. Full article