105 research outputs found

    Dependence of sub-micron vaterite container release properties on pH and ionic strength of the surrounding solution

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    We report on the synthesis and characterization of porous monodisperse vaterite containers with controllable average sizes from 400 nm to 10 mu m. Possible release strategies of enclosed substances via recrystallization or by pH-change are presented. As a model experiment, a fluorescent marker was encapsulated and imaged by two-photon microscopy to monitor the dye release. The release process was found to be controllable via the immersion medium's properties. Release times can be further tuned by covering the containers with additional polymer layers, creating a flexible system with promising perspectives for pharmaceutical applications

    Oxygen Gas Sensing Using a Hydrogel-Based Organic Electrochemical Transistor for Work Safety Applications

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    open8noOxygen depletion in confined spaces represents one of the most serious and underestimated dangers for workers. Despite the existence of several commercially available and widely used gas oxygen sensors, injuries and deaths from reduced oxygen levels are still more common than for other hazardous gases. Here, we present hydrogel-based organic electrochemical transistors (OECTs) made with the conducting polymer poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) as wearable and real-time oxygen gas sensors. After comparing OECT performances using liquid and hydrogel electrolytes, we identified the best PEDOT:PSS active layer and hydrogel coating (30 µm) combination for sensing oxygen in the concentration range of 13–21% (v/v), critical for work safety applications. The fast O2 solubilization in the hydrogel allowed for gaseous oxygen transduction in an electrical signal thanks to the electrocatalytic activity of PEDOT:PSS, while OECT architecture amplified the response (gain ̴ 104). OECTs proved to have comparable sensitivities if fabricated on glass and thin plastic substrates, (−12.2 ± 0.6) and (−15.4 ± 0.4) µA/dec, respectively, with low power consumption (<40 µW). Sample bending does not influence the device response, demonstrating that our real-time conformable and lightweight sensor could be implemented as a wearable, noninvasive safety tool for operators working in potentially hazardous confined spaces.The work was supported by the European Union FESR FSE, PON Research and Innovation 2014-2020 and FSC, project number ARS01-00996 "TEXT-STYLENuovi tessuti intelligenti e sostenibilimultisettoriali per il design creative e stileMade-in-Italy" and by the Italian Ministry of Economic Development 2020-Project "AlmaMater patents-Monitoraggio in continuo di pH e idratazione-MIRAGE".openFrancesco Decataldo, Filippo Bonafè, Federica Mariani, Martina Serafini, Marta Tessarolo, Isacco Gualandi, Erika Scavetta, Beatrice FraboniFrancesco Decataldo, Filippo Bonafè, Federica Mariani, Martina Serafini, Marta Tessarolo, Isacco Gualandi, Erika Scavetta, Beatrice Frabon

    Staphylococcus epidermidis is a safer surrogate of Staphylococcus aureus in testing bacterial filtration efficiency of face masks

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    Face masks play a role in reducing the spread of airborne pathogens, providing that they have a good filtration performance, are correctly fitted and maintained. Bacterial Filtration Efficiency (BFE) is a key indicator for evaluating filtration performance according to both European and US standards, requiring the use of Staphylococcus aureus loaded aerosol. However, the generation and handling of a Biohazard group 2 bacterium aerosol require a careful management of the biological risk and pose limitations to the accessibility to this method. To mitigate these drawbacks, we investigated the use of S. epidermidis ATCC 12228, a Biohazard group 1 bacterium, as surrogate in BFE test. To this end, tests with the surrogate strain were performed to tune the method. Then, three face mask models, representative for both surgical and community masks, were tested according to the standard method and then using an aerosolized suspension of S. epidermidis. BFE% values were calculated for each mask model and tested microorganisms. Results showed that BFE test can be performed using the S. epidermidis instead of S. aureus, preserving results validity and turnaround time, but reducing residual risk for laboratory operators

    seafloor integrity of the mar piccolo basin southern italy quantifying anthropogenic impact

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    ABSTRACTThe Mar Piccolo Basin is a coastal brackish marine ecosystem located along the northern coast of the Gulf of Taranto (Southern Italy). Despite the ecological relevance of the area (Site of Community Importance IT9130004, Regional Reserve 'Palude La Vela' EUAP1189), the entire basin is subjected to intensive human usage. The main activities include extensive mussel farming, important industrial activities, a military harbor and densely populated shores. The goal of our study was to spatially quantify human pressure within the basin and its relationship with biocoenoses. A broad set of data was integrated including acoustic remote data (obtained using a multibeam echosounder and side scan sonar devices), direct observations obtained by SCUBA diving and from a trawled camera, an orthophoto and ESRI® Imagery Basemap. At least eight categories of anthropogenic infrastructure and marks of past and present-day human activities were identified within the Mar Piccolo Basin water column and on the seafloor...

    Smart Bandaid Integrated with Fully Textile OECT for Uric Acid Real-Time Monitoring in Wound Exudate

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    : Hard-to-heal wounds (i.e., severe and/or chronic) are typically associated with particular pathologies or afflictions such as diabetes, immunodeficiencies, compression traumas in bedridden people, skin grafts, or third-degree burns. In this situation, it is critical to constantly monitor the healing stages and the overall wound conditions to allow for better-targeted therapies and faster patient recovery. At the moment, this operation is performed by removing the bandages and visually inspecting the wound, putting the patient at risk of infection and disturbing the healing stages. Recently, new devices have been developed to address these issues by monitoring important biomarkers related to the wound health status, such as pH, moisture, etc. In this contribution, we present a novel textile chemical sensor exploiting an organic electrochemical transistor (OECT) configuration based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) for uric acid (UA)-selective monitoring in wound exudate. The combination of special medical-grade textile materials provides a passive sampling system that enables the real-time and non-invasive analysis of wound fluid: UA was detected as a benchmark analyte to monitor the health status of wounds since it represents a relevant biomarker associated with infections or necrotization processes in human tissues. The sensors proved to reliably and reversibly detect UA concentration in synthetic wound exudate in the biologically relevant range of 220-750 μM, operating in flow conditions for better mimicking the real wound bed. This forerunner device paves the way for smart bandages integrated with real-time monitoring OECT-based sensors for wound-healing evaluation

    Reusing sterile cotton fabric barriers in the clinical practice: an observational and longitudinal study

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    Objetivo: analizar las características de barrera física y biológica de los campos de algodón utilizados como sistema de barrera estéril después de ser sometidos a múltiples usos y procesos en la práctica clínica. Método: estudio observacional longitudinal de seguimiento y evaluación de tela 100% algodón, utilizada como sistema de barrera estéril en un hospital de mediano porte. Se recolectaron muestras antes del uso (después de tres lavados) y después de tres, seis, nueve, 12 y 15 meses de uso y se evaluaron el número, grosor e integridad de los hilos, peso, absorción de agua y penetración húmeda de microorganismos. Resultados: después de 85 lavados, no cambió el número de hilos, aumentó el número de fibras deshilachadas y el volumen de agua absorbida. La prueba microbiológica mediante la metodología estándar alemana obtuvo un resultado negativo y la de penetración húmeda de microorganismos no mostró cambios significativos con el tiempo, a pesar de que una fracción de células microbianas pasó a través de las muestras de doble capa. Conclusión: las propiedades físicas de la tela 100% algodón utilizada como sistema de barrera estéril cambiaron con el uso/procesamiento; sin embargo, no interfirieron significativamente con los resultados obtenidos en las pruebas realizadas a la barrera microbiológica hasta los 85 lavados.Objective: to analyze the physical and biological barrier characteristics of cotton fields used as a sterile barrier system after multiple use and processing cycles in the clinical practice. Method: an observational and longitudinal study to monitor and evaluate 100% cotton fabric used as a sterile barrier system in a medium-sized hospital. Samples were collected before use (after three washes) and at three, six, nine, 12 and 15 months of use and evaluated for the number, thickness and integrity of threads, weight, water absorption and wet penetration by microorganisms. Results: after 85 washes, the number of threads remained unchanged, and the shredded fibers and the water volume absorbed were increased. The microbiological test using the German standard methodology obtained a negative result and wet penetration by microorganisms did not show significant changes over time, although a percentage of the microbial cells passed through the double-layer samples. Conclusion: the physical properties of 100% cotton used as a sterile barrier system changed with use/processing cycles; however, these alterations did not significantly interfere with the results obtained by the tests performed on the microbiological barrier up to 85 washes.Objetivo: analisar as características de barreira física e biológica de campos de algodão, que são utilizados como sistema de barreira estéril, após múltiplos usos e processamentos na prática clínica.Método:estudo longitudinal observacional de acompanhamento e de avaliação de tecido 100% algodão que foi utilizado como sistema de barreira estéril em um hospital de médio porte. Amostras foram coletadas antes do uso (após três lavagens) e com três, seis, nove, 12 e 15 meses de uso e avaliadas quanto ao número, à espessura e à integridade dos fios, peso, absorção de água e penetração úmida de micro-organismos. Resultados: após 85 lavagens, o número de fios permaneceu inalterado, porém aumentaram-se as fibras desfiadas e o volume de água absorvido. O teste microbiológico utilizando metodologia padrão alemão obteve resultado negativo; já o de penetração de úmida de micro-organismos não apresentou mudanças significativas ao longo do tempo, embora uma fração das células microbianas tenham passado pelas amostras de dupla camada. Conclusão: as propriedades físicas do tecido 100% algodão, utilizado como sistema de barreira estéril, alteraram com usos/processamentos; entretanto essas não interferiram significativamente nos resultados obtidos pelos testes realizados na barreira microbiológica até 85 lavagens

    Effects of Mushroom and Chicory Extracts on the Physiology and Shape of Prevotella intermedia, a Periodontopathogenic Bacterium

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    Contrary to the common assumption that food has a negative impact on oral health, research has shown that several foods contain a number of components with antibacterial and antiplaque activity. These natural compounds may be useful for improving daily oral hygiene. In this study we evaluate the mode of antimicrobial action of fractions of mushroom and red chicory extracts on Prevotella intermedia, a periodontopathogenic bacterium. The minimal inhibitory concentration corresponded to 0.5x compared to the natural food concentration for both extracts. This concentration resulted in a bacteriostatic effect in mushroom extract and in a slightly bactericidal effect in chicory extract. Cell mass continued to increase even after division stopped. As regards macromolecular synthesis, DNA was almost totally inhibited upon addition of either mushroom or chicory extract, and RNA to a lesser extent, while protein synthesis continued. Cell elongation occurred after septum inhibition as documented by scanning electron microscopy and cell measurement. The morphogenetic effects are reminiscent of the mode of action of antibiotics such as quinolones or β-lactams. The discovery of an antibiotic-like mode of action suggests that these extracts can be advantageously employed for daily oral hygiene in formulations of cosmetic products such as mouthwashes and toothpastes

    Selection of reference genes is critical for miRNA expression analysis in human cardiac tissue. A focus on atrial fibrillation

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    MicroRNAs (miRNAs) are emerging as key regulators of complex biological processes in several cardiovascular diseases, including atrial fibrillation (AF). Reverse transcription-quantitative polymerase chain reaction is a powerful technique to quantitatively assess miRNA expression profile, but reliable results depend on proper data normalization by suitable reference genes. Despite the increasing number of studies assessing miRNAs in cardiac disease, no consensus on the best reference genes has been reached. This work aims to assess reference genes stability in human cardiac tissue with a focus on AF investigation. We evaluated the stability of five reference genes (U6, SNORD48, SNORD44, miR-16, and 5S) in atrial tissue samples from eighteen cardiac-surgery patients in sinus rhythm and AF. Stability was quantified by combining BestKeeper, delta-Cq, GeNorm, and NormFinder statistical tools. All methods assessed SNORD48 as the best and U6 as the worst reference gene. Applications of different normalization strategies significantly impacted miRNA expression profiles in the study population. Our results point out the necessity of a consensus on data normalization in AF studies to avoid the emergence of divergent biological conclusions

    COLAEVA: Visual Analytics and Data Mining Web-Based Tool for Virtual Coaching of Older Adult Populations

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    The global population is aging in an unprecedented manner and the challenges for improving the lives of older adults are currently both a strong priority in the political and healthcare arena. In this sense, preventive measures and telemedicine have the potential to play an important role in improving the number of healthy years older adults may experience and virtual coaching is a promising research area to support this process. This paper presents COLAEVA, an interactive web application for older adult population clustering and evolution analysis. Its objective is to support caregivers in the design, validation and refinement of coaching plans adapted to specific population groups. COLAEVA enables coaching caregivers to interactively group similar older adults based on preliminary assessment data, using AI features, and to evaluate the influence of coaching plans once the final assessment is carried out for a baseline comparison. To evaluate COLAEVA, a usability test was carried out with 9 test participants obtaining an average SUS score of 71.1. Moreover, COLAEVA is available online to use and explore.This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 769830
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