Bloodstream infections (BSIs) are a major cause of morbidity and mortality in transplant recipients. The aim of this study is to describe the incidence, microbiology and outcomes of BSIs in transplant recipients in Spain. The Spanish Network for Research on Infection in Transplantation (RESITRA) is formed by 16 centers with transplant program in Spain. The incidence and characteristics of BSIs in transplant patients were obtained prospectively from the cohort. We included 3926 transplant recipients (2935 solid organ and 991 hematopoietic stem cell transplants). Overall, 730 episodes of BSIs were recorded with an incidence rate ranging from 3 episodes per 10 000 transplant days in kidney recipients to 44 episodes per 10 000 transplant days in allogeneic hematopoietic stem cell transplantation (HSCT). The most frequent sources were intravascular catheters and the most frequent microorganisms isolated were coagulase‐negative staphylococci. Crude mortality of BSIs was 7.8%, being highest in liver recipients (16%). Multidrug resistant nonfermentative gram‐negative BSIs had significantly worse prognosis than those caused by their susceptible counterparts (p = 0.015), but no differences were found between resistant and susceptible gram‐negative enteric bacilli, S. aureus or Candida spp. BSIs are still a major concern in transplant recipients. The increasing isolations of multiresistant microorganisms represent a challenge for the next years.

The objective of this study was to evaluate and compare tetrahedral and hexahedral finite element meshes of simplified and realistic proximal intact femur geometries. Theoretical expressions of stresses and strains were derived for the simplified model of the femur. For the analysis of the realistic geometry of the proximal femur, a CAD model of the third generation composite femur (Pacific Research Labs, Vashion Island, WA) was used and simulations were performed with Hyperworks (Altair Engineering, Inc., Troy, MI) finite element analysis software. Convergence tests with hexahedral (8- and 20-node brick-elements) and tetrahedral (4- and 10-node tetrahedrons) elements were analysed by comparing the periosteal von Mises stresses and principal strains at a selected point of the femur. The numerical periosteal strains were also compared with experimental ones to determine the accuracy of the finite elements. Overall, we concluded, for the simplified femur, that tetrahedral linear element allowed results more closely to theoretical ones, but hexahedral quadratic elements seem to be more stable and less influenced to the degree of refinement (NDOF) of the mesh. It was not possible to correlate these findings with those observed for the realistic proximal femur simulations where no significant differences were seen using refined meshes, with more than NDOF=20,000 for hexahedral elements.

Due to the increase in the life expectancy of world’s population, health care demands in terms of quality and accessibility are higher than ever before. Concerning the manufacturing of medical devices, the development of new biomaterials, new manufacturing methods and techniques have always been on researchers focus. In the development of a medical device, the choice of the proper material to be used is of the most importance, since its ability and capacity to fulfil the expected function will determine the success of the medical device itself. This work aims to do a review of those that are the most commonly used biomaterials. After an explanation on what are biomaterials and what defines them, a more in-depth approach is presented to each of the four major types of biomaterials: metal, polymer, ceramic, and composites, where their main characteristics and preferred applications in the area of medical devices are described.