367 research outputs found

    Isolation and characterization of buccal fat pad and dental pulp mscs from the same donor

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    Mesenchymal stem cells (MSCs) can be harvested from different sites in the oral cavity, representing a reservoir of cells useful for regenerative purposes. As direct comparisons between at least two types of MSCs deriving from the same patient are surprisingly rare in scientific literature, we isolated and investigated the osteoinductive potential of dental pulp stem cells (DPSCs) and buccal fat pad stem cells (BFPSCs). MSCs were isolated from the third molar dental pulp and buccal fat pads of 12 patients. The number of viable cells was quantified through manual count. Proliferation and osteodifferentiation assays, flow cytometry analysis of cell phenotypes, and osteocalcin release in vitro were performed. The isolation of BFPSCs and DPSCs was successful in 7 out of 12 (58%) and 3 out of 12 (25%) of retrieved samples, respectively. The yield of cells expressing typical stem cell markers and the level of proliferation were higher in BFPSCs than in DPSCs. Both BFP-SCs and DPSCs differentiated into osteoblast-like cells and were able to release a mineralized matrix. The release of osteocalcin, albeit greater for BFPSCs, did not show any significant difference between BFPSCs and DPSCs. The yield of MSCs depends on their site of origin as well as on the protocol adopted for their isolation. Our data show that BFP is a valuable source for the derivation of MSCs that can be used for regenerative treatments

    Additively Manufactured RCS for Small Satellites and Landers

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    After a fifty year absence, NASA’s return to the lunar surface under the Artemis Program – for long term human exploration and utilization – is driving commercial and academic opportunities for small satellite and small lander platforms (e.g., Commercial Lunar Payload Services program – CLPS). Bipropellant thrusters are a reliable, low risk, and flight proven method for the propulsion and attitude control that is required for complex maneuvers such entry, descent, and landing (EDL) or in-space proximity operations. However, due to the increasingly competitive commercial spaceflight market in the last decade, satellite subsystems must also be affordable to buy their way into the final mission design and engineering solution. Therefore starting in 2019, and based off prior satellite integration work, Aerojet Rocketdyne (AR) undertook an advanced propulsion development effort to combine modern metal additive manufacturing (AM) techniques with thrust scalable hypergolic MON-25 propulsion technology to create a high performance and fully integrated (i.e., multiple thrusters integrated into a single package) reaction control system (RCS) at a fraction of the production cost when compared to the heritage designs that are assembled from individual thrusters. The point-of-departure for the RCS design comes from a new line of additively manufactured thrusters that stably burn volatile MON-25 oxidizer with monomethylhydrazine (MMH) fuel at thrust levels of 5 lbf and 100 lbf. Cost at the subsystem level is lowered by the AM integration of parts and functions which reduces the build of materials, touch labor, and assembly time. In addition, AM allows the design to be adaptable to changing requirements such as the number of thrusters, orientation, and thrust level. Cost at the satellite level is reduced by leveraging MON-25’s lower freezing point of -55 °C (compared to traditional dinitrogen tetroxide oxidizer) to minimize mass, thermal, and power requirements while operating in deep-space environments. In addition, thruster operation at the equal volume mixture ratio for MMH/MON-25 allows for a modular approach to tank design and a predictable center of gravity during maneuvering. This paper provides an overview of the ISE-5 and the ISE-100 MON-25 thruster technology that powers the integrated designs as well as the development progress of the AM RCS concept itself. This includes reduction to practice activities such as proof-of-concept AM material test demonstrators and water flow test units

    α-Synuclein fibril and synaptic vesicle interactions lead to vesicle destruction and increased lipid-associated fibril uptake into iPSC-derived neurons

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    Monomeric alpha-synuclein (aSyn) is a well characterised protein that importantly binds to lipids. aSyn monomers assemble into amyloid fibrils which are localised to lipids and organelles in insoluble structures found in Parkinson’s disease patient’s brains. Previous work to address pathological aSyn-lipid interactions has focused on using synthetic lipid membranes, which lack the complexity of physiological lipid membranes. Here, we use physiological membranes in the form of synaptic vesicles (SV) isolated from rodent brain to demonstrate that lipid-associated aSyn fibrils are more easily taken up into iPSC-derived cortical i3Neurons. Lipid-associated aSyn fibril characterisation reveals that SV lipids are an integrated part of the fibrils and while their fibril morphology differs from aSyn fibrils alone, the core fibril structure remains the same, suggesting the lipids lead to the increase in fibril uptake. Furthermore, SV enhance the aggregation rate of aSyn, yet increasing the SV:aSyn ratio causes a reduction in aggregation propensity. We finally show that aSyn fibrils disintegrate SV, whereas aSyn monomers cause clustering of SV using small angle neutron scattering and high-resolution imaging. Disease burden on neurons may be impacted by an increased uptake of lipid-associated aSyn which could enhance stress and pathology, which in turn may have fatal consequences for neurons

    Sviluppo di modelli innovativi per il monitoraggio multiscala degli indicatori di servizi ecosistemici nelle foreste Mediterranee (Progetto MIMOSE).

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    Gli ecosistemi, attraverso le loro funzioni, forniscono un ampio range di beni e servizi, che risultano fondamentali per il benessere dell’uomo. Questi vengono complessivamente definiti Servizi Ecosistemici (SE). I SE possono essere intesi come un flusso di valori verso la società, quale risultato dello stato e della quantità del capitale naturale disponibile. Il mantenimento degli stocks del capitale naturale può permettere di prevedere i flussi futuri dei SE, assicurando quindi il benessere dell’uomo per le generazioni future. Il progetto FIRB 2012 MIMOSE è finalizzato allo sviluppo di un approccio multiscala innovativo e all’implementazione di strumenti previsionali volti al monitoraggio dei SE in habitat forestali Mediterranei. Un set di indicatori viene considerato per stimare i SE forniti dalle foreste, sviluppando strumenti integrati per il loro monitoraggio multiscala. Le attività di ricerca vertono allo sviluppo di un metodo statistico innovativo per la stima spaziale degli indicatori di SE, sulla base di dati disponibili a diversi livelli di scala spaziale. Sono realizzate mappe wall-to-wall per la fornitura dei SE, derivate da diversi domini spaziali, dal livello di scala locale sino ad aree forestali di grande estensione. I dati sugli indicatori dei SE sono forniti nel contesto di attività di campionamento già stabilite (raccolta dati a livello di aree di saggio e di popolamento), per poi applicare tecniche di spazializzazione per aggregare i dati raccolti su scala locale a livelli di scala più ampia (paesaggio, scala regionale); l’approccio utilizzato viene valutato attraverso l’applicazione di strumenti di monitoraggio in un set di aree test. Si procede quindi alla valutazione dei cambiamenti spazio-temporali nella previsione dei SE, considerando indicatori sensibili alla gestione forestale, ovvero capaci di evidenziare cambiamenti nella previsione di fornitura di beni e servizi ad opera dei sistemi forestali, in relazione a differenti scenari gestionali, con l’obiettivo di fornire indicazioni ai gestori forestali ed alle comunità locali per l’applicazione di pratiche di gestione che possano mantenere o incrementare la fornitura dei SE in un preciso contesto territoriale. Questo progetto permette di realizzare un’attenta analisi dei gaps esistenti negli attuali schemi di inventariazione in relazione alla fornitura dei SE, con l’obiettivo di dare indicazioni utili all’implementazione ed integrazione degli stessi mediante individuazione di nuovi indicatori, nell’ottica di una gestione forestale sostenibile. Le attività di ricerca in corso possono concretamente contribuire all’incorporazione dei SE nei processi decisionali connessi alla gestione dei paesaggi forestali, fornendo un’opportunità per comprendere la congruenza tra i diversi SE negli ambienti forestali

    Findings in multidetector computed tomography in the diagnosis of hepatocellular carcinoma in patients with cirrhosis and correlation with pathology of liver explants

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    Objetivos: Describir el comportamiento imagenológico del hepatocarcinoma en pacientes con cirrosis utilizando la tomografía computada multidetector (TCMD) dinámica y correlacionar los hallazgos con el grado histológico de los tumores. Materiales y métodos: Estudio retrospectivo, observacional y descriptivo, donde se evaluaron 51 nódulos de 32 pacientes trasplantados de hígado con diagnóstico de cirrosis. La anatomía patológica del explante fue utilizada como referencia y los nódulos con histología de hepatocarcinoma fueron analizados retrospectivamente en las tomografías computadas efectuadas antes del trasplante. Las tomografías se llevaron a cabo con técnica dinámica, evaluando las características más frecuentes reportadas en la literatura: realce arterial, lavado del realce, cápsula y vasos arteriales intratumorales. Resultados: Cuarenta y seis de 51 (90%) tumores mostraron realce arterial. De estos 46 tumores, 39 (85%) mostraron lavado del realce en la fase portal y/o tardía. De los 51, 5 (10%) fueron hipovasculares, 22 (43%) presentaron cápsula y 12 (24%) mostraron vasos arteriales intratumorales. La combinación de hallazgos más frecuente fue la asociación de realce arterial y lavado del realce en la fase portal-tardía (39/51 tumores: 76%), y el grado histológico más usual fue el II en 35 tumores (69%). Se hallaron asociaciones estadísticamente significativas entre el grado histológico de los tumores y los comportamientos imagenológicos realce arterial e hipovascular. Conclusión: En nuestra población, el hallazgo tomográfico de realce arterial con lavado del realce en tiempo portal y/o tardío fue observado en la mayoría de los tumores. Esto coincide con publicaciones anteriores y contribuye a fortalecer el valor de estos criterios para el diagnóstico del hepatocarcinoma.Objectives: To describe the imagenological behavior of hepatocellular carcinoma in cirrhotic patients using a dynamic multidetector computed tomography (MDCT) technique, and correlate these À ndings with histological tumor grades. Materials and methods: A retrospective, descriptive observational study was conducted to evaluate 51 nodules in 32 liver transplant patients diagnosed with liver cirrhosis. The pathology of liver explants was used as a reference. Nodules with hepatocellular carcinoma histopathology were retrospectively analyzed by computed tomography scans performed pre-transplant. Using a dynamic multidetector computed tomography technique, we evaluated the most common imagenological behavior reported in the literature: arterial enhancement, washout, capsule, and intratumoral arterial vessels. Results: Forty-six of 51 (90%) tumors showed arterial enhancement. Of the 46 tumors with arterial enhancement, 39 (85%) had washout in portal-late phase. Five of 51 (10%) were hypovascular. Twenty-two of 51 (43%) had capsule and 12 of 51 (24%) showed intratumoral arterial vessels. The more frequent image combination was the combination of arterial enhancement and washout (39 of 51 tumors or 76%). The most frequent histological grade was II (35 of 51 tumors or 69%). Statistically signiÀ cant relationships were found between histological grade tumors and imagenological behavior: arterial enhancement and hypovascular. Conclusion: In our population, arterial enhancement with washout in portal-late phases was observed in most of the tumors. Our results are consistent with previously reported studies, demonstrating the high reliability of this imaging pattern for the diagnosis of hepatocellular carcinoma.Fil: Haberman, D. Fundación Favaloro; ArgentinaFil: Castignola, M. Fundación Favaloro; ArgentinaFil: Mela, M. Fundación Favaloro; ArgentinaFil: Paladini, H. Fundación Favaloro; ArgentinaFil: Santilli, J. P. Fundación Favaloro; ArgentinaFil: Gruz, F. Fundación Favaloro; ArgentinaFil: Gondolesi, Gabriel Eduardo. Fundación Favaloro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Revealing Nanomechanical Domains and Their Transient Behavior in Mixed‐Halide Perovskite Films

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    Abstract: Halide perovskites are a versatile class of semiconductors employed for high performance emerging optoelectronic devices, including flexoelectric systems, yet the influence of their ionic nature on their mechanical behavior is still to be understood. Here, a combination of atomic‐force, optical, and compositional X‐ray microscopy techniques is employed to shed light on the mechanical properties of halide perovskite films at the nanoscale. Mechanical domains within and between morphological grains, enclosed by mechanical boundaries of higher Young's Modulus (YM) than the bulk parent material, are revealed. These mechanical boundaries are associated with the presence of bromide‐rich clusters as visualized by nano‐X‐ray fluorescence mapping. Stiffer regions are specifically selectively modified upon light soaking the sample, resulting in an overall homogenization of the mechanical properties toward the bulk YM. This behavior is attributed to light‐induced ion migration processes that homogenize the local chemical distribution, which is accompanied by photobrightening of the photoluminescence within the same region. This work highlights critical links between mechanical, chemical, and optoelectronic characteristics in this family of perovskites, and demonstrates the potential of combinational imaging studies to understand and design halide perovskite films for emerging applications such as photoflexoelectricity
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