The clinical performances of dental materials depend on their mechanical profiles, determining their long-term deformation and wear resistance. This paper describes a study on the mechanical properties, water absorption and morphological properties of a polymethyl methacrylate (PMMA) resin enriched with graphene-silver nanoparticles (Gr-Ag). Two different concentrations—1 and 2 wt.%—of Gr-Ag were loaded into the PMMA material. For the mechanical characterization, the compression behavior, flexural strength and tensile strength were evaluated. Optical microscopy in polarized light and scanning electron microscopy were used for filler analysis. The filler addition led to an improvement in all mechanical properties, with slight changes being derived from the filler content variation. Gr-Ag use led to an increase in the applied maximum loads. Moreover, 1 wt.% Gr-Ag determined an increase of 174% in the modulus of rupture, which indicates high flexibility.
In recent years, escitalopram (ESC) has been suggested to have different mechanisms of action beyond its well known selective serotonin reuptake inhibition. The aim of this study is to investigate the effects of escitalopram on oxidative stress, apoptosis, brain-derived neurotrophic factor (BDNF), Methyl-CpG-binding protein 2 (MeCP2), and oligodendrocytes number in the brain of chronic unpredictable mild stress-induced depressed rats. The animals were randomised in four groups (8 in each group): control, stress, stress + ESC 5 and stress + ESC 5/10. ESC was administered for 42 days in a fixed dose (5 mg/kg b.w.) or in an up-titration regimen (21 days ESC 5 mg/kg b.w. then 21 days ESC 10 mg/kg b.w.). Sucrose preference test (SPT) and elevated plus maze (EPM) were also performed. ESC improved the percentage of sucrose preference, locomotion and anxiety. ESC5/10 reduced the oxidative damage in the hippocampus and improved the antioxidant defence in the hippocampus and frontal lobe. ESC5/10 lowered caspase 3 activity in the hippocampus. Escitalopram had a modulatory effect on BDNF and the number of oligodendrocytes in the hippocampus and frontal lobe and also improved the MeCP2 expressions. The results confirm the multiple pathways implicated in the pathogenesis of depression and suggest that escitalopram exerts an antidepressant effect via different intricate mechanisms.
1 June 2018 in Mechanisms of Ageing and Development
Iron oxide nanoparticles (IONPs) have emerged as key materials in magnetic hyperthermia (MH), a minimally invasive cancer therapy capable of selectively inducing apoptosis, ferroptosis, and other cell death pathways while sparing surrounding healthy tissue. This review synthesizes advances in the design, functionalization, and biomedical application of magnetic nanoparticles (MNPs) for MH, highlighting strategies to optimize heating efficiency, biocompatibility, and tumor targeting. Key developments include tailoring particle size, shape, and composition; doping with metallic ions; engineering multicore nanostructures; and employing diverse surface coatings to improve colloidal stability, immune evasion, and multifunctionality. We discuss preclinical and clinical evidence for MH, its integration with chemotherapy, radiotherapy, and immunotherapy, and emerging theranostic applications enabling simultaneous imaging and therapy. Special attention is given to the role of MNPs in immunogenic cell death induction and metastasis prevention, as well as novel concepts for circulating tumor cell capture. Despite promising results in vitro and in vivo, clinical translation remains limited by insufficient tumor accumulation after systemic delivery, safety concerns, and a lack of standardized treatment protocols. Future progress will require interdisciplinary innovations in nanomaterial engineering, active targeting technologies, and real-time treatment monitoring to fully integrate MH into multimodal cancer therapy and improve patient outcomes.