Proteomic analysis of Salmonella enterica serovar Enteritidis following propionate adaptation

<p>Abstract</p> <p>Background</p> <p><it>Salmonella </it>Enteritidis is a highly prevalent and persistent foodborne pathogen and is therefore a leading cause of nontyphoidal gastrointestinal disease worldwide. A variety of stresses are endured throughout its infection cycle, including high concentrations of propionate (PA) within food processing systems and within the gut of infected hosts. Prolonged PA exposure experienced in such milieus may have a drastic effect on the proteome of <it>Salmonella </it>Enteritidis subjected to this stress.</p> <p>Results</p> <p>In this study, we used 2 D gel electrophoresis to examine the proteomes of PA adapted and unadapted <it>S</it>. Enteritidis and have identified five proteins that are upregulated in PA adapted cultures using standard peptide mass fingerprinting by MALDI-TOF-MS and sequencing by MALDI LIFT-TOF/TOF tandem mass spectrometry. Of these five, two significant stress-related proteins (Dps and CpxR) were shown (via qRT-PCR analysis) to be upregulated at the transcriptional level as well. Unlike the wild type when adapted to PA (which demonstrates significant acid resistance), PA adapted <it>S</it>. Enteritidis ∆<it>dps </it>and <it>S</it>. Enteritidis ∆<it>cpxR </it>were at a clear disadvantage when challenged to a highly acidic environment. However, we found the acid resistance to be fully restorable after genetic complementation.</p> <p>Conclusions</p> <p>This work reveals a significant difference in the proteomes of PA adapted and unadapted <it>S</it>. Enteritidis and affirms the contribution of Dps and CpxR in PA induced acid resistance.</p

Temporal changes in FFRCT-Guided Management of Coronary Artery Disease – Lessons from the ADVANCE Registry

Background: The ADVANCE registry is a large prospective study of outcomes and resource utilization in patients undergoing coronary computed tomography angiography (CCTA) and CT-based fractional flow reserve (FFRCT). As experience with new technologies and practices develops over time, we investigated temporal changes in the use of FFRCT within the ADVANCE registry. Methods: 5083 patients with coronary artery disease (CAD) on CCTA were prospectively enrolled in the ADVANCE registry and were divided into 3 equally sized cohorts based on the temporal order of enrollment per site. Demographics, CCTA and FFRCT findings, and clinical outcomes through 1-year follow-up, were recorded and compared between tertiles. Results: The number of patients with a ≥70% stenosis on CCTA was similar over time (33.6%, 30.9%, and 33.8% for cohort 1–3). The rate of positive FFRCT ≤0.80 was higher for cohorts 2 (67.3%) and 3 (74.6%) than for cohort 1 (57.1%, p < 0.001). Invasive FFR rates decreased from 25.8% to 22.4% between cohort 1 and 3 (p = 0.023). Moreover, patients with a FFRCT ≤0.80 were less frequently referred for invasive coronary angiography (ICA) (from 62.9% to 52.9%, p < 0.001), and underwent fewer revascularizations between cohort 1 and 3 (from 41.9% to 32.0%, p < 0.001). The prevalence of major events was low (1.2%) and similar between cohorts. Conclusions: Growing experience with FFRCT improved the likelihood of identifying hemodynamically significant CAD and safely reduced the need for ICA and revascularization in patients with anatomically significant disease even in the instance of an abnormal FFRCT