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Chiesa, I.

Publications and source records attributed to Chiesa, I..

3 recordsLinked to original sources

A stimuli-responsive ex vivo model of osteoarthritis demonstrates TLR4-mediated cartilage degradation and a Rapamycin-induced fast matrix recovery

BackgroundIn osteoarthritis (OA) TLR4 signaling leads to downstream activation of the phosphoinositide 3-kinases/ protein kinase B/ mammalian target of Rapamycin (PIK3/AKT/mTOR) pathway, a known modulator of autophagic mechanisms in chondrocytes. This paper focuses on creating a realistic ex vivo OA model that mimics elements of the pathophysiology of OA, allowing for further hypotheses-based investigations, and for use as a bench test for new therapeutic targets. ObjectiveTo study the downstream inflammatory and matrix changes in cartilage due to TLR4 signaling and the recovery achieved by a commonly used immunosuppressive drug, Rapamycin. MethodsIn an ex vivo 3D model based on healthy porcine cartilage explants, we mimicked the OA environment by LPS stimulation activating TLR4 signaling. Furthermore, we inhibited mTOR signaling via Rapamycin, which is accepted to attenuate the cartilage response to LPS-TLR4 activation. Histology and immunohistochemistry were used to evaluate the structural and biomolecular modifications driven by LPS and Rapamycin. ResultsThe explant model captured key features of OA, such as extracellular matrix degeneration and altered autophagy. The OA-like changes in the model were driven by TLR4 activation and mTOR signaling, well-known OA-related molecular pathways, and reversed by Rapamycin. ConclusionWe demonstrate that our explant model is responsive to LPS stimulation, leading to activation of OA-related biomolecular pathways, closely mimicking the native physiological processes. This evidence supports the potential of our model to act as a platform for OA studies, in particular related to the gut-joint axis in age-related OA, and for the screening of new disease-modifying molecules.

bioengineering↗

Argentina Explores Its Bathyal and Abyssal Zone for the First Time Using an ROV: New Biodiversity Discoveries and Unprecedented Public Engagement

Between July 23 and August 12, 2025, members of the scientific group Grupo de Estudios del Mar Profundo de Argentina (GEMPA) and collaborators conducted the Talud Continental IV expedition in the Mar del Plata Canyon. The expedition was conducted aboard the R/V Falkor (too) in partnership with Schmidt Ocean Institute (SOI), marking the first deployment of a Remotely Operated Vehicle (ROV) in Argentinean bathyal and abyssal waters. The Mar del Plata Canyon was explored in 2012 and 2013 by CONICET researchers using bottom trawls aboard the R/V Puerto Deseado (CONICET, Argentina). This new expedition combined high-definition video surveys, acoustic seafloor mapping, and physicochemical water-column characterization, with in situ sensing and sampling of fauna (animal specimens, zooplankton, and environmental DNA), water, sediments, and rock to characterize biodiversity and habitats between 880 and 3900 m. The expedition revealed extensive Bathelia cold-water coral reefs, soft-coral gardens, and more than 40 species suspected to be new to science, six of which have already been formally described. Anthropogenic debris, including plastics and fishing gear, was recorded at multiple stations, reaching even the deepest sites, underscoring the extent of human influence on these environments. The Talud Continental IV expedition was successful both scientifically and in promoting deep-ocean literacy and engagement, with broad outreach conducted through SOIs outreach and community engagement programs. The Ship-to-Shore program connected scientists on board with students and educators through live interactive sessions, engaging over 900 students from 19 institutions across Argentina and the United States. The live ROV divestreams, broadcast through SOIs YouTube and Twitch platforms, reached record levels of public engagement, with [~]19 million total views by July 23rd. The national and international press responded with extensive coverage and interview requests, resulting in over 3,900 international stories. Scientists continued to engage with the public after the expedition through talks at schools and public institutions. The expeditions achievements promise to usher in a new era of scientific discovery in the Southwestern Atlantic and underscore the value of integrating exploration, conservation, and outreach to inspire wonder and curiosity about the deep-sea in society. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=179 SRC="FIGDIR/small/726651v3_ufig1.gif" ALT="Figure 1"> View larger version (138K): org.highwire.dtl.DTLVardef@1457548org.highwire.dtl.DTLVardef@116f19aorg.highwire.dtl.DTLVardef@14fbb26org.highwire.dtl.DTLVardef@187c3a4_HPS_FORMAT_FIGEXP M_FIG C_FIG

ecology↗

4D bioprinted self-folding scaffolds enhance cartilage formation in the engineering of trachea

Trachea defects that required surgical interventions are increasing in number in the recent years, especially for pediatric patients. However, current gold standards, such as biological grafts and synthetic prothesis, do not represent an effective solution, due to the lack of mimicry and regeneration capability. Bioprinting is a cutting-edge approach for the fabrication of biomimetic scaffold to empower tissue engineering toward trachea replacement. In this study, we developed a self-folding gelatin-based bilayer scaffold for trachea engineering, exploiting the 4D bioprinting approach, namely the fabrication of dynamic scaffolds, able to shape morph in a predefined way after the application of an environmental stimulus. Indeed, starting form a 2D flat position, upon hydration, this scaffold forms a closed tubular structure. An analytical model, based on Timoshenkos beam thermostats, was developed, and validated to predict the radius of curvature of the scaffold according to the material properties and the scaffold geometry. The 4D bioprinted structure was tested with airway fibroblast, lung endothelial cells and ear chondral progenitor cells (eCPCs) toward the development of a tissue engineered trachea. Cells were seeded on the scaffold in its initial flat position, maintained their position after the scaffold actuation and proliferated over or inside it. The ability of eCPCs to differentiate towards mature cartialge was evaluated. Interestingly, real-time PCR revealed that differentiating eCPCs on the 4D bioprinted scaffold promote healthy cartilage formation, if compared with eCPCs cultured on 2D static scaffold. Thus, eCPCs can perceive scaffold folding and its final curvature and to react to it, towards the formation of mature cartilage for the airway.

bioengineering↗