Browsing by Author "San Martín, Sebastián"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- ItemCustomized normothermic machine perfusion decreases ischemia–reperfusion injury compared with static cold storage in a porcine model of liver transplantation(2023) Riveros González, Sergio; Marino C., Carlo; Ochoa Suazo, Gabriela Susana; Soto Muñoz, Dagoberto Igor; Alegría Vargas, Leyla; Zenteno, María José ; San Martín, Sebastián; Brañes, Alejandro; Achurra Tirado, Pablo; Rebolledo Acevedo, RolandoBackground: Liver transplantation has been demonstrated to be the best treatment for several liver diseases, while grafts are limited. This has caused an increase in waiting lists, making it necessary to find ways to expand the number of organs available for transplantation. Normothermic perfusion (NMP) of liver grafts has been established as an alternative to static cold storage (SCS), but only a small number of perfusion machines are commercially available. Methods: Using a customized ex situ machine perfusion, we compared the results between ex situ NMP and SCS preservation in a porcine liver transplant model. Results: During NMP, lactate concentrations were 80% lower after the 3-h perfusion period, compared with SCS. Bile production had a 2.5-fold increase during the NMP period. After transplantation, aspartate transaminase (AST) and alanine transaminase (ALT) levels were 35% less in the NMP group, compared to the SCS group. In pathologic analyses of grafts after transplant, tissue oxidation did not change between groups, but the ischemia–reperfusion injury score was lower in the NMP group. Conclusion: NMP reduced hepatocellular damage and ischemia–reperfusion injury when compared to SCS using a customized perfusion machine. This could be an alternative for low-income countries to include machine perfusion in their therapeutic options.
- ItemDevelopment of an implantable three-dimensional model of a functional pathogenic multispecies biofilm to study infected wounds(2022) Cárdenas Calderón, Camila Valentina; Veloso Giménez, Valentina del Carmen; González, Tamara; Wozniak Banchero, Aniela; García, Patricia; San Martín, Sebastián; Varas, Juan F.; Carrasco-Wong, Ivo; Vera, Mario; Egaña, José T.Chronic wounds cannot heal due to impairment of regeneration, mainly caused by the persistent infection of multispecies biofilms. Still, the effects of biofilm wound infection and its interaction with the host are not fully described. We aimed to study functional biofilms in physiological conditions in vitro, and their potential effects in health and regeneration in vivo. Therefore, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis were seeded in collagen-based scaffolds for dermal regeneration. After 24 h, scaffolds had bacterial loads depending on the initial inoculum, containing viable biofilms with antibiotic tolerance. Afterwards, scaffolds were implanted onto full skin wounds in mice, together with daily supervision and antibiotic treatment. Although all mice survived their health was affected, displaying fever and weight loss. After ten days, histomorphology of scaffolds showed high heterogeneity in samples and within groups. Wounds were strongly, mildly, or not infected according to colony forming units, and P. aeruginosa had higher identification frequency. Biofilm infection induced leucocyte infiltration and elevated interferon-γ and interleukin-10 in scaffolds, increase of size and weight of spleen and high systemic pro-calcitonin concentrations. This functional and implantable 3D biofilm model allows to study host response during infection, providing a useful tool for infected wounds therapy development.