University of Graz

About: University of Graz is a education organization based out in Graz, Steiermark, Austria. It is known for research contribution in the topics: Population & Context (language use). The organization has 17934 authors who have published 37489 publications receiving 1110980 citations. The organization is also known as: Carolo Franciscea Graecensis & Karl Franzens Universität.

Development and maturation of Escherichia coli K-12 biofilms.

Abstract: The development and maturation of E. coli biofilms in flow-chambers was investigated. We found that the presence of transfer constitutive IncF plasmids induced biofilm development forming structures resembling those reported for Pseudomonas aeruginosa. The development occurred in a step-wise process: (i). attachment of cells to the substratum, (ii). clonal growth and microcolony formation, and (iii). differentiation into expanding structures rising 70-100 microm into the water phase. The first two steps were the same in the plasmid-carrying and plasmid-free strains, whereas the third step only occurred in conjugation pilus proficient plasmid-carrying strains. The final shapes of the expanding structures in the mature biofilm seem to be determined by the pilus configuration, as various mutants affected in the processing and activity of the transfer pili displayed differently structured biofilms. We further provide evidence that flagella, type 1 fimbriae, curli and Ag43 are all dispensable for the observed biofilm maturation. In addition, our results indicate that cell-to-cell signalling mediated by autoinducer 2 (AI-2) is not required for differentiation of E. coli within a biofilm community. We suggest on the basis of these results that E. coli K-12 biofilm development and maturation is dependent on cell-cell adhesion factors, which may act as inducers of self-assembly processes that result in differently structured biofilms depending on the adhesive properties on the cell surface.

Effect of high-dose vitamin D3 on hospital length of stay in critically ill patients with vitamin D deficiency: the VITdAL-ICU randomized clinical trial.

Abstract: different (hospital mortality: 28.3% [95% CI, 22.6%-34.5%] for vitamin D3 vs 35.3% [95% CI, 29.2%-41.7%] for placebo; hazard ratio [HR], 0.81 [95% CI, 0.58-1.11]; P = .18; 6-month mortality: 35.0% [95% CI, 29.0%-41.5%] for vitamin D3 vs 42.9% [95% CI, 36.5%-49.4%] for placebo; HR, 0.78 [95% CI, 0.58-1.04]; P = .09). For the severe vitamin D deficiency subgroup analysis (n = 200), length of hospital stay was not significantly different between the 2 study groups: 20.1 days (IQR, 12.9-39.1) for vitamin D3 vs 19.0 days (IQR, 11.6-33.8) for placebo. Hospital mortality was significantly lower with 28 deaths among 98 patients (28.6% [95% CI, 19.9%-38.6%]) for vitamin D3 compared with 47 deaths among 102 patients (46.1% [95% CI, 36.2%-56.2%]) for placebo (HR, 0.56 [95% CI, 0.35-0.90], P for interaction = .04), but not 6-month mortality (34.7% [95% CI, 25.4%-45.0%] for vitamin D3 vs 50.0% [95% CI, 39.9%-60.1%] for placebo; HR, 0.60 [95% CI, 0.39-0.93], P for interaction = .12). CONCLUSIONS AND RELEVANCE Among critically ill patients with vitamin D deficiency, administration of high-dose vitamin D3 compared with placebo did not reduce hospital length of stay, hospital mortality, or 6-month mortality. Lower hospital mortality was observed in the severe vitamin D deficiency subgroup, but this finding should be considered hypothesis generating and requires further study.