239700 research outputs found
Sort by
[Strengthen and expand vaccination provision in prisons to promote access to preventive tools and health equity]
No full textUnraveling resistance mechanisms to the novel nucleoside analog RX-3117 in lung cancer: insights into DNA repair, cell cycle dysregulation and targeting PKMYT1 for improved therapy
No full textBackground: Nucleoside analogues are crucial in treating non-small cell lung cancer (NSCLC), but resistance hampers patient outcomes. The cytidine analogue RX-3117 shows promise in gemcitabine-resistant cancers, yet mechanisms underlying acquired resistance to this drug remain unexplored. This study includes a comprehensive investigation into RX-3117 resistance mechanisms by leveraging new preclinical models and cutting-edge genomic tools, including a CRISPR-Cas9 knockout screen and transcriptomics. Methods: NSCLC cell lines A549 and SW1573 were exposed to stepwise increasing concentrations of RX-3117 to establish stable resistant subclones, confirmed by SRB and clonogenic assays. Intracellular RX-3117 nucleotide levels were measured via LC/MS-MS, prompting the evaluation and modulation of the expression of key metabolic enzymes by Western blot and siRNA. A CRISPR-Cas9 screen identified genes whose loss increased RX-3117 sensitivity, while RNA-sequencing with differential expression analyses revealed resistance-related pathways, further investigated through cell cycle distribution, knock-out, and ELISA assays. Results: Resistant clones exhibited decreased accumulation of RX-3117 nucleotides, which however, was not associated to reduced expression of activation enzymes (UCK2, UMPK, CMPK, NME1/NDPK, RR1 and RR2). Instead, increased expression was observed in certain DNA repair and deactivation enzymes (NT5C3) but pharmacological inhibition and silencing of the latter did not circumvent resistance. Remarkably, a comprehensive approach with CRISPR-Cas9 screen highlighted DNA-repair and cell cycle determinants as key sensitizing genes. XL-PCR and RNA-sequencing confirmed aberrations in DNA-repair and pathways involved in cell cycle regulation. Knock-out and pharmacological inhibition validated the role of PKMYT1, a protein kinase involved in G2/M transition and genomic stability. RX-3117-resistant A549 cells showed enhanced sensitivity to the PKMYT1 inhibitor lunresertib and its synergism with RX-3117, suggesting further studies, especially in patients with high PKMYT1 expression who have significantly shorter survival rates, as observed in public databases and validated in an internal cohort of NSCLC patients. Conclusion: By integrating CRISPR-Cas9 with functional assays and transcriptomics, our study established a framework for decoding resistance mechanisms and highlights potential therapeutic strategies to enhance RX-3117 efficacy in NSCLC. We demonstrated for the first time that aberrant DNA repair and cell cycle dysregulation led resistance, identifying PKMYT1 as a promising target
DNA gyrase-inhibitory antimicrobial anthraquinone from the endophytic Sordariomycetes fungus Diaporthe perseae
No full textFungi of the order Diaporthales are prolific sources of antimicrobial secondary metabolites. In this paper, we describe antimicrobial and antituberculosis anthraquinones (AQs) from Diaporthe perseae, an endophytic fungus isolated and identified from the endemic Philippine medicinal plant Uvaria alba (Annonaceae). Large-scale rice fermentation of D. perseae yielded an ethyl acetate extract which was subjected to a series of chromatographic purification to yield three compounds. Spectroscopic analyses allowed the identification of the anthraquinone compounds citreorosein (1), skyrin (2), and rugulosin A (3). AQs 1 and 3 showed broad-spectrum against Gram-positive bacteria (Micrococcus luteus, Bacillus subtilis, and Staphylococcus aureus) (MIC = 1.0–2.0 μg/mL), however only 3 demonstrated strong inhibition against Gram-negative bacterial strains (Escherichia coli, Pseudomonas aeruginosa, and Chromobacterium violaceum) and non-TB mycobacteria (Mycobacterium smegmatis) (MIC = 8.25–66.0 μg/mL). AQ 3 also exhibited inhibition against both M. tuberculosis (Mtb) H37Rv (Microplate Alamar Blue Assay; MABA MIC = 29.2 μg/mL) and its non-replicating persistent strain (Low-Oxygen Recovery Assay; LORA MIC = 30.3 μg/mL). To explore the potential mechanism of 3, DNA supercoiling assay was performed. Thus, rugulosin A (3) displayed inhibition of Mtb. DNA gyrase, an enzyme necessary for genomic replication via ATP-dependent DNA relaxation mechanisms. Molecular docking and molecular dynamics revealed strong, stable binding affinity of 3 (BE = -9.5 kcal/mol) and its tautomer 4 (BE = -9.6 kcal/mol) within the active pocket of the MtbDNA gyrase. Overall, rugulosin A (3) represents a promising antibiotic prototype with in vitro and in silico activity against M. tuberculosis, and identifies DNA gyrase as therapeutic target for anthraquinone antimycobacterials
Italian farmers between interest in new technologies and willingness to adopt: evolution and trends
No full textThe recent Covid-19 pandemic has reshaped the scenarios of global economic priorities and the agri-food sector is, without a doubt, involved in changes whose effects are still ongoing. Although the sector has shown considerable resilience towards changes, there is an evolution in the approach of farmers themselves regarding the use of new digital technologies, which are now pervasive in a large part of the agri-food supply chains. The objective of this research is to detect the interest of Italian farmers towards these new digital technologies that can be used within the agricultural system and their propensity to invest in the purchase and implementation of new technologies. To respond to the objectives of the research, an online survey was carried out, directly asking farmers their interest rate and their propensity to invest in new technologies, with the CAWI method in March 2024. The questionnaire, composed of 3 blocks of questions, had the objective of evaluating the current rate of use of technologies, the investments made by companies in the last 3 years and the motivations underlying current and future choices on the use of technologies. The results of the research aim to present themselves as a preliminary study that highlights how the sector has evolved in the last 3 years, what the motivations behind the farmers' choices may be and what the future trajectories may be that can help make the Italian agri-food supply chain to be more sustainable
Declinazioni di didattica “inclusiva” nelle grammatiche per la scuola secondaria di primo grado: analisi di strategie, strumenti e contenuti
No full textIl contributo propone una riflessione sulla cosiddetta “didattica inclusiva” a partire da una breve revisione terminologica sulla questione e dall’analisi di un campione di vo-lumi di grammatica circolanti nelle scuole secondarie di primo grado in Italia. L’obiet-tivo è quello di indagare quali siano le scelte compiute in termini di selezione di con-tenuti, strategie didattiche e strumenti proposti nelle sezioni dedicate alla didattica inclusiva, così da avanzare proposte concrete per la progettazione di materiali acces-sibili per tutte le tipologie di apprendenti.This paper offers a reflection on so-called “inclusive education” beginning with a brief terminological review of the topic and an analysis of a sample of grammar textbooks currently used in lower secondary schools in Italy. The aim is to investigate the choices made in terms of content selection, teaching strategies, and tools presented in sections dedicated to inclusive education, in order to propose concrete suggestions for designing accessible materials for all types of learners
Precision design of dextran-permeated agarose hydrogels matching adipose stem cell adhesion timescales
No full textViscoelasticity is now recognised as a key parameter in modulating cell behaviour. Tailoring time-dependent materials to elicit specific cellular responses is, however, a challenge because of the intricate relationship between the substrate relaxation time (τrel) and the cell sensing time-window which depends on the time required for the formation of focal adhesions (τb) and the duration of their lifetime (τL). Here, we introduce a novel design approach to guide cell behaviour based on the cell-perceived Deborah number, De = τrel/τL, arguing that for De > 1 and De < 1, substrates promote cell differentiation because stable adhesions and sustained tension drive mechanotransduction and lineage-specific differentiation on the basis of substrate stiffness. Instead, cell stemness is maintained in the De ∼1, whereby excessive mechanical signalling is prevented as cells balance adhesion stability and plasticity. The design workflow consists in modelling substrate τrel, enabling the selection of the optimal gel formulation according to the cell-perceived De. The workflow was applied to agarose gels with different dextran concentrations in the liquid phase, which act as modulators of mechanical time-dependent properties. To predict the relaxation times for these gels, we developed an in-silico model which integrates their structural and transport properties. Our results show that the gels have an almost constant equilibrium elastic modulus, while their τrel decreases with increasing dextran concentration in the liquid phase. Considering adipose-derived mesenchymal stem cells (ADSCs) and their characteristics sensing times, we defined dextran concentrations to mimic the different De conditions in the agarose gels. Experimental cell investigations confirmed the validity of the design approach: ADSC differentiation, highlighted by YAP nuclear translocation, was promoted in the case of De < 1 and De > 1, respectively eliciting adipogenic and osteogenic lineages. On the other hand, cells maintained their stemness when De ∼1. This study provides novel insights on the interplay between hydrogel viscoelasticity and cellular behaviour and paves the way for precision design of viscoelastic biomaterials for in-vitro studies and regenerative medicine
Numerical Investigation of NOx emissions in a gas turbine burner using hydrogen-ammonia and partially cracked ammonia fuel blends: A combined LES and CRN approach
No full textThe increasing interest in ammonia as a carbon-free fuel alternative underscores the need for accurate numerical models capable of predicting the complex combustion chemistry and associated NOx emissions. This study presents a detailed numerical investigation of NOx emissions in a gas turbine burner operating with hydrogen-ammonia and cracked ammonia fuel blends, utilizing Large Eddy Simulation (LES) and Chemical Reactor Network (CRN) methodologies. The primary objective is to validate a Computational Fluid Dynamics (CFD) model against experimental data collected under atmospheric conditions. The experimental campaign involved a non-premixed burner with ammonia concentrations up to 70%, generating a NOx emission database useful for model validation. LES were performed using a tabulated chemistry model, using a detailed chemical kinetic scheme alongside additional transport equations for the main species responsible for the formation of pollutants, to better capture the combustion characteristics and emissions. Furthermore, a CRN model was developed based on time-averaged LES data. This approach facilitated a more detailed and wide examination of NOx formation mechanisms and pathways. The results indicate that both LES and CRN models predict NOx emissions with an accuracy within 10% of experimental measurements, although LES slightly underestimates NOx levels and overestimates outlet temperatures by 3%. The CRN model, derived from LES data, offers a computationally efficient means for analyzing key emission pathways. Furthermore, a comparison was conducted between the combustion characteristics of the hydrogen-ammonia blend and a mixture resulting from an 80% ammonia cracking process. This was achieved through the utilization of both LES and CFD-CRN methodologies, with the objective of analyzing the impact of cracking on NOx emissions, while maintaining a constant burner power and equivalence ratio. In conclusion, the study demonstrates the effectiveness of combining LES and CRN methodologies in predicting NOx emissions and analyzing NO formation pathways from NH3/H2/N2 combustion. The utilization of a cracked-derived mixture resulted in a 25% reduction in NOx emissions. The findings provide valuable insights for optimizing gas turbine operation while addressing NOx emission concerns, contributing to the development of cleaner combustion technologies
Cyberdelics: Virtual reality hallucinations modulate cognitive-affective processes
No full textIntroduction
Psychedelics were explored for their potential in the mental health field. However, research was delayed by concerns over short-term side effects and long-term consequences of substance use. Technological advances enabled the development of Hallucinatory Visual Virtual Experiences (HVVEs), namely psychedelic experiences simulations in immersive virtual reality. This study investigated HVVEs’ impact on cognitive flexibility, affective response, and autonomic activity.
Methods
50 healthy participants underwent assessments of cognitive flexibility, control inhibition, emotional response, and autonomic activity at baseline. Participants were then exposed to two 10-minute immersive virtual reality (IVR) experiences: ‘The Secret Garden’ and its hallucinated counterpart created using Google DeepDream algorithm. All measures were presented after each video, in addition to the flow experience assessment.
Results
Post-HVVE, participants demonstrated enhanced cognitive flexibility and inhibitory control. They reported increased flow-absorption and decreased flow-fluency. Both IVR experiences reduced positive affects and state anxiety compared to baseline; additionally, IVR reduced heart rate and sympathetic activity compared to baseline.
Conclusions
HVVEs produced psychedelic positive effects on cognitive and emotional functioning. The complex emotional and autonomic profile mimicked awakened relaxation that, in conjunction with the cognitive flexibility enhancement, could offer the unique opportunity to exploit psychedelic advantages while mitigating risks, opening new avenues for therapeutic approaches
Europeanization and Education from the Aftermath of the Second World War to the Post-Pandemic Era
No full textThis essay lays the groundwork for the narrative that unfolds in the ensuing chapters. It offers an enticing glimpse into the book’s structure and contents
