515 research outputs found

    Energy release as a parameter for fatigue design of additive manufactured metals

    Get PDF
    Additive manufacturing (AM) is spreading in a wide range of industrial fields. The influence of the printing parameters on the mechanical performance is still an open issue among researchers, particularly when dealing with fatigue loads, which can lead to an unexpected failure. Classical fatigue tests require a large amount of time and materials to be consumed. Compared to the traditional fatigue assessment, the thermographic method (TM) is able to derive in a very rapid way the SN curve and fatigue limit of the material monitoring its energetic release during fatigue tests. In this work, for the first time, the energetic release during fatigue test has been evaluated in specimens made of AISI 316L, obtained by SLM technique. Compared to literature data, the specimens show premature failure, even at low stress levels, with brittle fracture surfaces. The internal microstructure seems to be strictly related to the energetic release of the material

    New frontiers on adjuvants drug strategies and treatments in periodontitis

    Get PDF
    Causes of the progression of periodontitis such as an imbalance between the immune response by the host by the release of inflammatory mediators in the response of the oral pathogenic dysbiotic biofilm have been identified. New insights on specific cell signaling pathways that appear during periodontitis have attracted the attention of researchers in the study of new personalised approaches for the treatment of periodontitis. The gold standard of non‐surgical therapy of perio-dontitis involves the removal of supra and subgingival biofilm through professional scaling and root planing (SRP) and oral hygiene instructions. In order to improve periodontal clinical outcomes and overcome the limitations of traditional SRP, additional adjuvants have been developed in recent decades, including local or systemic antibiotics, antiseptics, probiotics, anti‐inflammatory and anti-resorptive drugs and host modulation therapies. This review is aimed to update the current and recent evolution of therapies of management of periodontitis based on the adjunctive and target therapies. Moreover, we discuss the advances in host modulation of periodontitis and the impact of targeting epigenetic mechanisms approaches for a personalised therapeutic success in the management of periodontitis. In conclusion, the future goal in periodontology will be to combine and personalise the periodontal treatments to the colonising microbial profile and to the specific response of the individual patient

    Water extract of Cryphaea heteromalla (Hedw.) D. Mohr bryophyte as a natural powerful source of biologically active compounds

    Get PDF
    Bryophytes comprise of the mosses, liverworts, and hornworts. Cryphaea heteromalla, (Hedw.) D. Mohr, is a non-vascular lower plant belonging to mosses group. To the date, the most chemically characterized species belong to the liverworts, while only 3.2% and 8.8% of the species belonging to the mosses and hornworts, respectively, have been investigated. In this work, we present Folin–Ciocalteu and oxygen radical absorbance capacity (ORAC) data related to crude extracts of C. heteromalla obtained by three different extraction solvents: pure water (WT), methanol:water (80:20 v/v) (MET), and ethanol:water (80:20 v/v) (ETH). The water extract proved to be the best solvent showing the highest content of biophenols and the highest ORAC value. The C. heteromalla-WT extract was investigated by HPLC-TOF/MS (High Performance Liquid Chromatography-Time of Flight/Mass Spectrometry) allowing for the detection of 14 compounds, five of which were phenolic compounds, derivatives of benzoic, caffeic, and coumaric acids. Moreover, the C. heteromalla WT extract showed a protective effect against reactive oxygen species (ROS) generation induced by tert-butyl hydroperoxide (TBH) on the murine NIH-3T3 fibroblast cell line

    Curcumin loaded polymeric vs. Lipid nanoparticles: Antioxidant effect on normal and hypoxic olfactory ensheathing cells

    Get PDF
    Background: Curcumin (Cur) shows anti-inflammatory and antioxidant effects on central nervous system diseases. The aim of this study was to develop Cur-loaded polymeric and lipid nanoparticles for intranasal delivery to enhance its stability and increase antioxidant effect on olfactory ensheathing cells (OECs). Methods: The nanosuspensions were subjected to physico-chemical and technological evaluation through photon correlation spectroscopy (PCS), differential scanning calorimetry (DSC) and UV-spectrophotometry. The cytotoxicity studies of nanosuspensions were carried out on OECs. A viability test was performed after 24 h of exposure of OECs to unloaded and curcumin-loaded nanosuspensions. The potential protective effect of Cur was assessed on hypoxic OECs cells. Uptake studies were performed on the same cell cultures. Thermal analysis was performed to evaluate potential interaction of Cur with a 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) biomembrane model. Results: PCS analysis indicated that lipid and polymeric nanosuspensions showed a mean size of 127.10 and 338.20 nm, respectively, high homogeneity and negative zeta potential. Incorporation of Cur into both nanocarriers increased drug stability up to 135 days in cryoprotected freeze-dried nanosuspensions. Cell viability was improved when hypoxic OECs were treated with Cur-loaded polymeric and lipid nanosuspensions compared with the control. Conclusions: Both nanocarriers could improve the stability of Cur as demonstrated by technological studies. Biological studies revealed that both nanocarriers could be used to deliver Cur by intranasal administration for brain targeting

    Toward the use of temporary tattoo electrodes for impedancemetric respiration monitoring and other electrophysiological recordings on skin

    Get PDF
    The development of dry, ultra-conformable and unperceivable temporary tattoo electrodes (TTEs), based on the ink-jet printing of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on top of commercially available temporary tattoo paper, has gained increasing attention as a new and promising technology for electrophysiological recordings on skin. In this work, we present a TTEs epidermal sensor for real time monitoring of respiration through transthoracic impedance measurements, exploiting a new design, based on the application of soft screen printed Ag ink and magnetic interlink, that guarantees a repositionable, long-term stable and robust interconnection of TTEs with external “docking” devices. The efficiency of the TTE and the proposed interconnection strategy under stretching (up to 10%) and over time (up to 96 h) has been verified on a dedicated experimental setup and on humans, fulfilling the proposed specific application of transthoracic impedance measurements. The proposed approach makes this technology suitable for large-scale production and suitable not only for the specific use case presented, but also for real time monitoring of different bio-electric signals, as demonstrated through specific proof of concept demonstrators

    Impact of Periodontitis on Glycemic Control and Metabolic Status in Diabetes Patients: Current Knowledge on Early Disease Markers and Therapeutic Perspectives

    Get PDF
    Diabetes mellitus and periodontitis are two of the most common chronic diseases affecting the world's population, and they are intimately linked. For several years, in fact, it has been known that there is an interdependent relationship between the two diseases: Diabetes promotes the destruction of periodontal tissues, and periodontal disease negatively affects glycemic control. In relation to the control of dental plaque and oral dysbiosis responsible for periodontal disease, both nonsurgical and surgical therapy associated with proper home hygiene procedures have emerged as essential for good glycemic control. Moreover, several evidences suggest the essential role played by the control of periodontal disease in preventing the onset of the most common complications of diabetes: cardiovascular diseases, retinopathies, and other systemic diseases. The aim of this study is to update the current knowledge on the bi-univocal relationship between diabetes and periodontitis and the impact of therapy in the optimal management of these two disorders. From the information found in the literature, it has emerged that the correct treatment of periodontal disease in diabetic patients represents one of the main mechanisms and means currently established and valid to control periodontal disease and glucose metabolism and prevent the onset or development of diabetic complications

    Therapeutic and Metagenomic Potential of the Biomolecular Therapies against Periodontitis and the Oral Microbiome: Current Evidence and Future Perspectives

    Get PDF
    The principles of periodontal therapy are based on the control of microbial pathogens and host factors that contribute to biofilm dysbiosis, with the aim of modulating the progression of periodontitis and periodontal tissue destruction. It is currently known how differently each individual responds to periodontal treatment, depending on both the bacterial subtypes that make up the dysbiotic biofilm and interindividual variations in the host inflammatory response. This has allowed the current variety of approaches for the management of periodontitis to be updated by defining the goals of target strategies, which consist of reducing the periodontopathogenic microbial flora and/or modulating the host-mediated response. Therefore, this review aims to update the current variety of approaches for the management of periodontitis based on recent target therapies. Recently, encouraging results have been obtained from several studies exploring the effects of some targeted therapies in the medium- and long-term. Among the most promising target therapies analyzed and explored in this review include: cell-based periodontal regeneration, mediators against bone resorption, emdogain (EMD), platelet-rich plasma, and growth factors. The reviewed evidence supports the hypothesis that the therapeutic combination of epigenetic modifications of periodontal tissues, interacting with the dysbiotic biofilm, is a key step in significantly reducing the development and progression of disease in periodontal patients and improving the therapeutic response of periodontal patients. However, although studies indicate promising results, these need to be further expanded and studied to truly realize the benefits that targeted therapies could bring in the treatment of periodontitis

    Prompt dipole radiation in fusion reactions

    Get PDF
    The prompt gamma ray emission was investigated in the 16A MeV energy region by means of the 36,40Ar+96,92Zr fusion reactions leading to a compound nucleus in the vicinity of 132Ce. We show that the prompt radiation, which appears to be still effective at such a high beam energy, has an angular distribution pattern consistent with a dipole oscillation along the symmetry axis of the dinuclear system. The data are compared with calculations based on a collective bremsstrahlung analysis of the reaction dynamics
    • 

    corecore