16 research outputs found
Development and application of an electrochemical plate coupled with immunomagnetic beads (ELIME) array for salmonella enterica detection in meat samples
Salmonella is one of the main organisms causing outbreaks of foodborne illness, and meat is one of the major vehicles of salmonellosis throughout the world. A novel analytical immunosensor array, based on a 96-well electrochemical plate coupled with immunomagnetic beads (ELIME array), is proposed for the detection of Salmonella in meat samples. After an optimization study, using Salmonella enterica serotype Enteritidis as reference antigen, the ability of the method to interact with a large number of Salmonella serovars commonly present in food was evaluated. The assay was then used to analyze samples of pork, chicken, beef, and turkey experimentally inoculated with Salmonella as well as real samples. The results were compared with those from the International Standard of Organization (ISO) culture method. The comparison showed that the ELIME array is able to detect a low number of Salmonella cells (1-10 CFU per 25 g) after only 6 h of incubation in a pre-enrichment broth. The investigation revealed a very good agreement between culture and ELIME array methods for meat samples, reducing the time for performing the analysis and obtaining the results quickly
Hippo pathway effectors control cardiac progenitor cell fate by acting as dynamic sensors of substrate mechanics and nanostructure
Stem cell responsiveness to extracellular matrix (ECM) composition and mechanical cues has been the subject of a number of investigations so far, yet the molecular mechanisms underlying stem cell mechano-biology still need full clarification. Here we demonstrate that the paralog proteins YAP and TAZ exert a crucial role in adult cardiac progenitor cell mechano-sensing and fate decision. Cardiac progenitors respond to dynamic modifications in substrate rigidity and nanopattern by promptly changing YAP/TAZ intracellular localization. We identify a novel activity of YAP and TAZ in the regulation of tubulogenesis in 3D environments and highlight a role for YAP/TAZ in cardiac progenitor proliferation and differentiation. Furthermore, we show that YAP/TAZ expression is triggered in the heart cells located at the infarct border zone. Our results suggest a fundamental role for the YAP/TAZ axis in the response of resident progenitor cells to the modifications in microenvironment nanostructure and mechanics, thereby contributing to the maintenance of myocardial homeostasis in the adult heart. These proteins are indicated as potential targets to control cardiac progenitor cell fate by materials design
Modified Screen-Printed Electrodes Based on Oxidized Graphene Nanoribbons for the Selective Electrochemical Detection of Several Molecules
Oxidized few layers of graphene for the assembling of nano-micelles for the celaning of the black crust from peperino substrata
In this work, few layers of functionalized graphene nanoribbons (FLGs) have been synthesised, using the unzipping oxidative reaction, from SWCNTs, used here as graphene precursor. After a full characterization study (under a topographic and structural point of view), FLGs nano-micelles, assembled using Tween20, as working medium, have been also applied on the selected artwork surfaces (affected by the environmental alterations) as new cleaning strategy. In particular, the cleaning efficiency of the FLGs, as nano-carrier, to release, in a controlled way, the cleaning agent (i.e.; the surfactant agent, Tween20) has been evaluated, and the corresponding performances were presented
Functionalized graphene nanoribbons as nano-carrier for several bio-catalysts: a new selective poultice and consolidation treatment based on the controlled release of cleaning agent of deteriorated sultural heritage surfaces
In the current study, we present a new cleaning procedure and a new consolidation treatment, based_ on engineered Few Layers of Graphene (FLGs) nanoribbons, immobilizing enlyrnes such as Glucose Oxidase (GOD), Carbonic Anydrase (CA) and Urease (U). The preliminary evaluation of their cleaning efficiency and their consolidation performances , have been also reported, respectively
Porous Chitosan Films Support Stem Cells and Facilitate Sutureless Tissue Repair
Photochemical tissue bonding with chitosan-based adhesive films is an experimental surgical technique that avoids the risk of thermal tissue injuries and the use of sutures to maintain strong tissue connection. This technique is advantageous over other tissue repair methods as it is minimally invasive and does not require mixing of multiple components before or during application. To expand the capability of the film to beyond just a tissue bonding device and promote tissue regeneration, in this study, we designed bioadhesive films that could also support stem cells. The films were modified with oligomeric chitosan to tune their erodibility and made porous through freeze-drying for better tissue integration. Of note, porous adhesive films (pore diameter â110 μm), with 10% of the chitosan being oligomeric, could retain similar tissue bonding strengths (13-15 kPa) to that of the nonporous chitosan-based adhesives used in previous studies when photoactivated. When tested in vitro, these films exhibited a mass loss of â20% after 7 days, swelling ratios of â270-300%, a percentage elongation of â90%, and both a tensile strength and Young's modulus of â1 MPa. The physical properties of the films were suitable for maintaining the viability and multipotency of bone-marrow-derived human mesenchymal stem cells over the duration of culture. Thus, these biocompatible, photoactivated porous, and erodible adhesive films show promise for applications in controlled cell delivery and regenerative medicine
Development of a recombinant Fab-fragment based electrochemical immunosensor for deoxynivalenol detection in food samples
Ex Vivo Preservation of Ovine Periosteum Using a Perfusion Bioreactor System
Periosteum is a highly vascularized membrane lining the surface of bones. It plays essential roles in bone repair following injury and reconstruction following invasive surgeries. To broaden the use of periosteum, including for augmenting in vitro bone engineering and/or in vivo bone repair, we have developed an ex vivo perfusion bioreactor system to maintain the cellular viability and metabolism of surgically resected periosteal flaps. Each specimen was placed in a 3D printed bioreactor connected to a peristaltic pump designed for the optimal flow rates of tissue perfusate. Nutrients and oxygen were perfused via the periosteal arteries to mimic physiological conditions. Biochemical assays and histological staining indicate component cell viability after perfusion for almost 4 weeks. Our work provides the proof-of-concept of ex vivo periosteum perfusion for long-term tissue preservation, paving the way for innovative bone engineering approaches that use autotransplanted periosteum to enhance in vivo bone repair