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Background: Abdominal aortic aneurysms can be either treated by an open abdominal aortic aneurysm repair or an endovascular repair. Comparing clinical predictors of outcomes and those which influence survival rates in the long term is important in determining the choice of treatment offered and the decision-making process with patients. Aims: To determine the influence of pre-existing clinical predictors and perioperative determinants on late survival of elective open abdominal aortic aneurysm repair and endovascular repair at a tertiary hospital. Methods: Consecutive patients undergoing elective abdominal aortic aneurysm repair from 1990 to 2013 were included. Data were collected from a prospectively acquired database and death data were gathered from the Queensland state death registry. Pre-existing risks and perioperative factors were assessed independently. Kaplan-Meier and Cox regression modeling were performed. Results: During the study period, 1340 abdominal aortic aneurysms were repaired electively, of which 982 were open abdominal aortic aneurysm repair. The average age was 72.4 years old and 81.7% were males. The cumulative percentage survival rates for open abdominal aortic aneurysms repair at 5, 10, 15 and 20 years were 79, 49, 31 and 22, respectively. The corresponding 5-, 10- and 15-year survival rates for endovascular repair were not significantly different at 75, 49 and 33%, respectively (P = 0.75). Predictors of reduced survival were advanced age, American Society of Anaesthesiology scores, chronic obstructive pulmonary disease, renal impairment, bifurcated grafts, peripheral vascular disease and congestive heart failure. Conclusions: Open repair offers a good long-term treatment option for patients with an abdominal aortic aneurysm and in our experience there is no significant difference in late survival between open abdominal aortic aneurysms repair and endovascular repair. Consideration of the factors identified in this study that predict reduced long-term survival for open abdominal aortic aneurysms repair and endovascular repair should be considered when deciding repair of abdominal aortic aneurysm. [ABSTRACT FROM AUTHOR]

The Gram-positive model organism Bacillus subtilis responds to environmental stressors by activating the alternative sigma factor σ B . The sensing apparatus upstream of σ B activation is thought to consist of cytoplasmic stressosomes-megadalton-sized protein complexes that include five paralogous proteins known as RsbRs. The RsbRs are presumed to be involved in stress sensing and the subsequent response. Perturbations to the RsbR complement in stressosomes by engineering cells that produce only one of the RsbR paralogs ("single-RsbR strains") lead to altered σ B response dynamics with respect to timing and magnitude. Here, we asked whether such changes to σ B response dynamics impact the relative fitness of a strain. We competed strain pairs with different RsbR complements under ethanol and sodium chloride stress and found not only differences in relative fitness among wild-type and single-RsbR strains but also different relative fitness values in the two different stressors. We found that the presence of RsbRA, which dominates the wild-type σ B response, enhances fitness in ethanol but is detrimental to fitness in NaCl. Meanwhile, RsbRD-only cells were among the most fit in NaCl. Strains producing hybrid RsbR fusion proteins displayed different fitness values that depended on the RsbR proteins from which they were derived. Our results here suggest that σ B response dynamics can impact fitness, highlighting the physiological importance of the unusual stressosome-based general stress response system of B. subtilis ., Importance: The model bacterium Bacillus subtilis uses cytoplasmic multiprotein complexes, termed stressosomes, to activate the alternative sigma factor σ B when facing environmental stresses. We have previously shown that genetically manipulating the complement of putative sensor proteins in stressosomes can alter the dynamics of the σ B response in terms of its magnitude and timing. However, it is unknown whether these response dynamics impact the fitness of cells challenged by environmental stressors. Here, we examine the fitness of strains with different σ B responses by competing strain pairs in exponential-phase co-cultures under environmental stress. We find that strains with different response dynamics show different competitive indices that differ by stressor. These results suggest that the dynamics of the σ B response can affect the fitness of cells facing environmental stress, highlighting the relevance of different σ B dynamics., Competing Interests: The authors declare no conflict of interest.