Raman microscopic analysis of dry-surface biofilms on clinically relevant materials

Moist/hydrated biofilms have been well-studied in the medical area, and their association with infections is widely recognized. In contrast, dry-surface biofilms (DSBs) on environmental surfaces in healthcare settings have received less attention. DSBs have been shown to be widespread on commonly used items in hospitals and to harbor bacterial pathogens that are known to cause healthcare-acquired infections (HAI). DSBs cannot be detected by routine surface swabbing or contact plates, and studies have shown DSBs to be less susceptible to cleaning/disinfection products. As DSBs are increasingly reported in the medical field, and there is a likelihood they also occur in food production and manufacturing areas, there is a growing demand for the rapid in situ detection of DSBs and the identification of pathogens within DSBs. Raman microspectroscopy allows users to obtain spatially resolved information about the chemical composition of biofilms, and to identify microbial species. In this study, we investigated Staphylococcus aureus mono-species DSB on polyvinylchloride blanks and stainless steel coupons, and dual-species (S. aureus/Bacillus licheniformis) DSB on steel coupons. We demonstrated that Raman microspectroscopy is not only suitable for identifying specific species, but it also enables the differentiation of vegetative cells from their sporulated form. Our findings provide the first step towards the rapid identification and characterization of the distribution and composition of DSBs on different surface areas

Cardiac rehabilitation outcome after transcatheter aortic valve implantation

Patients with severe aortic stenosis are increasingly treated with transcatheter aortic valve implantation (TAVI) as a safer option to surgical aortic valve replacement (sAVR). Similar to many other heart diseases, after the specific therapeutic intervention patients are eligible for cardiac rehabilitation (CR) for the purpose of functional recovery. Thus far, CR after both sAVR and TAVI has been used to a limited extent, as shown by the availability of only two meta-analyses including 5 studies and 6 studies, respectively. Recent observational studies reported a significant improvement in functional indexes such as the Barthel scale and the 6-minute walk test (6MWT). We evaluated the outcome of CR in patients after TAVI treatment by measuring changes in the commonly used Barthel scale and 6MWT and adding the short physical performance battery (SPPB) scale as an index to assess lower extremity function. All indexes demonstrated a significant improvement, namely p<0.001 with the Barthel scale, p=0.043 for the 6MWT, and p=0.002 for SPPB. These results confirm the significant improvement of the Barthel scale and 6MWT reported in the previous meta-analysis and suggest the utility of SPPB as a further index of efficacy of CR in patients with severe aortic stenosis treated with TAVI