Study of biological effects by ultra-soft X rays on V79 cell line: preliminary results

Radiobiological studies essentially focuse on DNA damage, according to a dose-dependant approach. The use of ultra-soft X-rays (500 eV) allows us to determine the biological effects from the damage on peripheral and cytoplasmatic structures, such as plasmatic membrane and organelles, without DNA is involved directly by radiation. The in vitro model chosen is V79 cell line (isolated from the lung of a normal Chinese Hamster). To reach this aim, we have developed: • an experimental layout to obtain ultra-soft X rays from monocromatic spherical mirror (500eV) and a second apparatus based on a plane copper mirror at grazing angular incidence (300-510 eV); • a custom biological sample holder, in order to be trasparent to X rays and visible light and realized by biocompatible materials; • analysis methods based on mycroscopy observation with appropriate set-up and study of different end-points as viability assay and ROS detection. In this article, we present the preliminary results and apparatus

Hand Hygiene Practices during the COVID-19 Pandemic in Northern Italy: Assessment of Compliance Rates Measured by Direct Observation and Alcohol-Based Handrub Usage

Hand hygiene (HH) is among the most effective measures for reducing the transmission of healthcare-associated infections and SARS-CoV-2. We aimed to assess HH practices among healthcare workers (HCWs) of three hub hospitals in Northern Italy during the COVID-19 pandemic, by assessing HH compliance measured by direct observation and alcohol-based handrub usage. An observational study was conducted over a period of three months, between February and April 2021. HH compliance audits were conducted using the WHO My 5 Moments for HH approach. Multivariable logistic regression was used to evaluate independent predictors of HH compliance: ward type, HCW category and HH indication. Spearman correlation was used to investigate the relationship between HH compliance and alcohol-based handrub consumption. In total, 2880 HH opportunities were observed, with an overall compliance of 68%. Significant differences were found in compliance rates across ward types, HCW categories and HH indications. The mean alcohol-based handrub usage among included wards was 41.63 mL/PD. No correlation was identified between compliance rates and alcohol-based handrub consumption (ρ 0.023, p 0.943). This study provided a snapshot of HH practices in a pandemic context, which could be useful as a reference for future studies

Solid and Semisolid Innovative Formulations Containing Miconazole-Loaded Solid Lipid Microparticles to Promote Drug Entrapment into the Buccal Mucosa

The currently available antifungal therapy for oral candidiasis (OC) has various limita- tions restricting its clinical use, such as short retention time, suboptimal drug concentration and low patients compliance. These issues could be overcome using micro or nanotechnology. In par- ticular, solid lipid microparticles (SLMs) resulted as a particularly promising penetration enhancer carrier for lipophilic drugs, such as the antifungal miconazole (MCZ). Based on these considera- tions, cetyl decanoate (here synthesized without the use of metal catalysis) was employed together with 1-hexadecanol to prepare MCZ-loaded SLMs. These resulted in a powder composed of 45–300 µm diameter solid spherical particles, able to load a high amount of MCZ in the amorphous form and characterized by a melting temperature range perfectly compatible with oromucosal admin- istration (35–37 °C). Moreover, when compared to Daktarin ® 2% oral gel in ex vivo experiments, SLMs were able to increase up to three-fold MCZ accumulation into the porcine buccal mucosa. The prepared SLMs were then loaded into a buccal gel or a microcomposite mucoadhesive buccal film and evaluated in terms of MCZ permeation and/or accumulation into porcine buccal mucosa by using lower doses than the conventional dosage form. The promising results obtained high- lighted an enhancement in terms of MCZ accumulation even at low doses. Furthermore, the pre- pared buccal film was eligible as stable, reproducible and also highly mucoadhesive. Therefore, the formulated SLMs represent a penetration enhancer vehicle suitable to reduce the dose of lipophilic drugs to be administered to achieve the desired therapeutic effects, as well as being able to be ef- fectively embedded into easily administrable solid or semisolid dosage forms

Tailoring Antimicrobial Stewardship (AMS) Interventions to the Cultural Context: An Investigation of AMS Programs Operating in Northern Italian Acute-Care Hospitals

Antibiotic misuse and overuse are important contributors to the development of antimicrobial resistance (AMR). Antimicrobial stewardship (AMS) programs are coordinated sets of actions aiming to promote appropriate antibiotic use, improving patient outcomes whilst reducing AMR. Two main organizational models for AMS programs have been described: restrictive strategies (RS) vs. enabling strategies (ES). Evaluating and understanding social and cultural influences on antibiotic decision-making are critical for the development of successful and sustainable context-specific AMS programs. Characteristics and surrogate outcomes of AMS programs operating in acute-care hospitals of Piedmont in north-western Italy were investigated. The aim of this study was assessing whether RS vs. ES operating in our context were associated with different outcomes in terms of total antimicrobial usage and percentage of methicillin-resistant Staphylococcus aureus (MRSA) and carbapenem-resistant enterobacteria (CRE) over invasive isolates. In total, 24 AMS programs were assessed. ES were more frequently chosen compared to RS, with the latter being implemented only in broader AMS programs involving enabling components (combined strategy, CS). This study found no difference in evaluated outcomes among hospitals implementing ES vs. CS, suggesting both approaches could be equally valid in our context

Integrated MicroRNA-mRNA Profiling Identifies Oncostatin M as a Marker of Mesenchymal-Like ER-Negative/HER2-Negative Breast Cancer

MicroRNAs (miRNAs) simultaneously modulate different oncogenic networks, establishing a dynamic system of gene expression and pathway regulation. In this study, we analyzed global miRNA and messenger RNA (mRNA) expression profiles of 17 cell lines representing different molecular breast cancer subtypes. Spearman's rank correlation test was used to evaluate the correlation between miRNA and mRNA expression. Hierarchical clustering and pathway analysis were also performed. Publicly available gene expression profiles (n = 699) and tumor tissues (n = 80) were analyzed to assess the relevance of key miRNA-regulated pathways in human breast cancer. We identified 39 significantly deregulated miRNAs, and the integration between miRNA and mRNA data revealed the importance of immune-related pathways, particularly the Oncostatin M (OSM) signaling, associated with mesenchymal-like breast cancer cells. OSM levels correlated with genes involved in the inflammatory response, epithelial-to-mesenchymal transition (EMT), and epidermal growth factor (EGF) signaling in human estrogen receptor (ER)-negative/human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Our results suggest that the deregulation of specific miRNAs may cooperatively impair immune and EMT pathways. The identification of the OSM inflammatory pathway as an important mediator of EMT in triple-negative breast cancer (TNBC) may provide a novel potential opportunity to improve therapeutic strategies

Engineering a 3D in vitro model of human skeletal muscle at the single fiber scale

The reproduction of reliable in vitro models of human skeletal muscle is made harder by the intrinsic 3D structural complexity of this tissue. Here we coupled engineered hydrogel with 3D structural cues and specific mechanical properties to derive human 3D muscle constructs ("myobundles") at the scale of single fibers, by using primary myoblasts or myoblasts derived from embryonic stem cells. To this aim, cell culture was performed in confined, laminin-coated micrometric channels obtained inside a 3D hydrogel characterized by the optimal stiffness for skeletal muscle myogenesis. Primary myoblasts cultured in our 3D culture system were able to undergo myotube differentiation and maturation, as demonstrated by the proper expression and localization of key components of the sarcomere and sarcolemma. Such approach allowed the generation of human myobundles of ~10 mm in length and ~120 \u3bcm in diameter, showing spontaneous contraction 7 days after cell seeding. Transcriptome analyses showed higher similarity between 3D myobundles and skeletal signature, compared to that found between 2D myotubes and skeletal muscle, mainly resulting from expression in 3D myobundles of categories of genes involved in skeletal muscle maturation, including extracellular matrix organization. Moreover, imaging analyses confirmed that structured 3D culture system was conducive to differentiation/maturation also when using myoblasts derived from embryonic stem cells. In conclusion, our structured 3D model is a promising tool for modelling human skeletal muscle in healthy and diseases conditions

SNAI1 is upregulated during muscle regeneration and represses FGF21 and ATF3 expression by directly binding their promoters

During skeletal myogenesis, the zinc-finger transcription factors SNAI1 and SNAI2, are expressed in proliferating myoblasts and regulate the transition to terminally differentiated myotubes while repressing pro-differentiation genes. Here, we demonstrate that SNAI1 is upregulated in vivo during the early phase of muscle regeneration induced by bupivacaine injury. Using shRNA-mediated gene silencing in C2C12 myoblasts and whole-transcriptome microarray analysis, we identified a collection of genes belonging to the endoplasmic reticulum (ER) stress pathway whose expression, induced by myogenic differentiation, was upregulated in absence of SNAI1. Among these, key ER stress genes, such as Atf3, Ddit3/Chop, Hspa5/Bip, and Fgf21, a myokine involved in muscle differentiation, were strongly upregulated. Furthermore, by promoter mutant analysis and Chromatin immune precipitation assay, we demonstrated that SNAI1 represses Fgf21 and Atf3 in proliferating myoblasts by directly binding to multiple E boxes in their respective promoter regions. Together, these data describe a new regulatory mechanism of myogenic differentiation involving the direct repressive action of SNAI1 on ER stress and Fgf21 expression, ultimately contributing to maintaining the proliferative and undifferentiated state of myoblasts

MicroRNA-21 links epithelial-to-mesenchymal transition and inflammatory signals to confer resistance to neoadjuvant trastuzumab and chemotherapy in HER2-positive breast cancer patients

Patients with primary HER2-positive breast cancer benefit from HER2-targeted therapies. Nevertheless, a significant proportion of these patients die of disease progression due to mechanisms of drug resistance. MicroRNAs (miRNAs) are emerging as critical core regulators of drug resistance that act by modulating the epithelial- to-mesenchymal transition (EMT) and cancer-related immune responses. In this study, we investigated the association between the expression of a specific subset of 14 miRNAs involved in EMT processes and immune functions and the response to neoadjuvant trastuzumab and chemotherapy in 52 patients with HER2-overexpressing breast tumors. The expression of only a single miRNA, miR-21, was significantly associated with residual disease (p = 0.030) and increased after trastuzumab-chemotherapy (p = 0.012). A target prediction analysis coupled with in vitro and in vivo validations revealed that miR-21 levels inversely correlated with the expression of PTEN (rs = −0.502; p = 0.005) and PDCD4 (rs = −0.426; p = 0.019), which differentially influenced the drug sensitivity of HER2-positive breast cancer cells. However, PTEN expression was only marginally associated with residual disease. We further demonstrated that miR-21 was able to affect the response to both trastuzumab and chemotherapy, triggering an IL-6/STAT3/NF-κB-mediated signaling loop and activating the PI3K pathway. Our findings support the ability of miR-21 signaling to sustain EMT and shape the tumor immune microenvironment in HER2-positive breast cancer. Collectively, these data provide a rationale for using miR-21 expression as a biomarker to select trastuzumab-chemotherapy-resistant HER2-positive breast cancer patients who may benefit from treatments containing PI3K inhibitors or immunomodulatory drugs