30 research outputs found
Human cardiac progenitor cell grafts as unrestricted source of supernumerary cardiac cells in healthy murine hearts
Human heart harbors a population of resident progenitor cells that can be isolated by stem cell antigen-1 antibody and expanded in culture. These cells can differentiate into cardiomyocytes in vitro and contribute to cardiac regeneration in vivo. However, when directly injected as single cell suspension, less than 1%-5% survive and differentiate. Among the major causes of this failure are the distressing protocols used to culture in vitro and implant progenitor cells into damaged hearts. Human cardiac progenitors obtained from the auricles of patients were cultured as scaffoldless engineered tissues fabricated using temperature-responsive surfaces. In the engineered tissue, progenitor cells established proper three-dimensional intercellular relationships and were embedded in self-produced extracellular matrix preserving their phenotype and multipotency in the absence of significant apoptosis. After engineered tissues were leant on visceral pericardium, a number of cells migrated into the murine myocardium and in the vascular walls, where they integrated in the respective textures. The study demonstrates the suitability of such an approach to deliver stem cells to the myocardium. Interestingly, the successful delivery of cells in murine healthy hearts suggests that myocardium displays a continued cell cupidity that is strictly regulated by the limited release of progenitor cells by the adopted source. When an unregulated cell source is added to the system, cells are delivered to the myocardium. The exploitation of this novel concept may pave the way to the setup of new protocols in cardiac cell therapy. STEM CELLS 2011;29:2051-206
Oral zinc sulphate as primary therapeutic intervention in a child with Wilson disease
An 8-year-old boy with an hepatic form of Wilson disease was treated with oral zinc sulphate as the primary and sole therapy. After 4 months, liver function had dramatically improved, and the parameters characterizing copper metabolism had also normalized
Finishing of metal additive manufactured parts by abrasive fluidized bed machining
A characteristic of metal additive manufactured (AM) components fabricated by Laser Powder Bed Fusion process (L-PBF) is the texture of the surface, primarily originated by melting and solidification of the powder material. This mechanism leads to an average surface roughness of 8-25 μm, depending on the material properties and process parameters. In some applications, AM parts require a surface smoothing process to meet part specifications. Conventional finishing processes may not be appropriate to finish the complex geometries that are typical of AM products, such as deep cavities and intricate through holes. Abrasive fluidized bed (AFB) machining is a recent finishing process developed at the University of Rome Tor Vergata that employs an abrasive fluidized bed to improve surface finish by material erosion. This work aims to explore the capability of the AFB method as finishing method for AM products. Thus, a specimen with curved surfaces and internal holes was designed and several copies were produced by L-PBF process. The samples were then subjected to the AFB surface finishing treatment. The influence of the operational parameters on the finishing performance was investigated. The achievable surface roughness and the deviations of the part geometry induced by the finishing process were identified by dimensional and surface inspection. From the inspection results, it was possible to assess the effectiveness of the process and to identify capabilities, limitations and possible improvements
Optimizing the Safety Profile of Everolimus by Delayed Initiation in De Novo Heart Transplant Recipients: Results of the Prospective Randomized Study EVERHEART
Although everolimus potentially improves long-term heart transplantation (HTx) outcomes, its early postoperative safety profile had raised concerns and needs optimization