Prognostic accuracy of age-adapted SOFA, SIRS, PELOD-2, and qSOFA for in-hospital mortality among children with suspected infection admitted to the intensive care unit

PURPOSE:The Sepsis-3 consensus task force defined sepsis as life-threatening organ dysfunction caused by dysregulated host response to infection. However, the clinical criteria for this definition were neither designed for nor validated in children. We validated the performance of SIRS, age-adapted SOFA, quick SOFA and PELOD-2 scores as predictors of outcome in children. METHODS:We performed a multicentre binational cohort study of patients < 18 years admitted with infection to ICUs in Australia and New Zealand. The primary outcome was ICU mortality. SIRS, age-adapted SOFA, quick SOFA and PELOD-2 scores were compared using crude and adjusted area under the receiver operating characteristic curve (AUROC) analysis. RESULTS:Of 2594 paediatric ICU admissions due to infection, 151 (5.8%) children died, and 949/2594 (36.6%) patients died or experienced an ICU length of stay ≥ 3 days. A ≥ 2-point increase in the individual score was associated with a crude mortality increase from 3.1 to 6.8% for SIRS, from 1.9 to 7.6% for age-adapted SOFA, from 1.7 to 7.3% for PELOD-2, and from 3.9 to 8.1% for qSOFA (p < 0.001). The discrimination of outcomes was significantly higher for SOFA (adjusted AUROC 0.829; 0.791-0.868) and PELOD-2 (0.816; 0.777-0.854) than for qSOFA (0.739; 0.695-0.784) and SIRS (0.710; 0.664-0.756). CONCLUSIONS:SIRS criteria lack specificity to identify children with infection at substantially higher risk of mortality. We demonstrate that adapting Sepsis-3 to age-specific criteria performs better than Sepsis-2-based criteria. Our findings support the translation of Sepsis-3 into paediatric-specific sepsis definitions and highlight the importance of robust paediatric organ dysfunction characterization.Luregn J. Schlapbach, Lahn Straney, Rinaldo Bellomo, Graeme MacLaren, David Pilche

Effect of promoter architecture on the cell-to-cell variability in gene expression

According to recent experimental evidence, the architecture of a promoter, defined as the number, strength and regulatory role of the operators that control the promoter, plays a major role in determining the level of cell-to-cell variability in gene expression. These quantitative experiments call for a corresponding modeling effort that addresses the question of how changes in promoter architecture affect noise in gene expression in a systematic rather than case-by-case fashion. In this article, we make such a systematic investigation, based on a simple microscopic model of gene regulation that incorporates stochastic effects. In particular, we show how operator strength and operator multiplicity affect this variability. We examine different modes of transcription factor binding to complex promoters (cooperative, independent, simultaneous) and how each of these affects the level of variability in transcription product from cell-to-cell. We propose that direct comparison between in vivo single-cell experiments and theoretical predictions for the moments of the probability distribution of mRNA number per cell can discriminate between different kinetic models of gene regulation.Comment: 35 pages, 6 figures, Submitte

The Generation of Promoter-Mediated Transcriptional Noise in Bacteria

Noise in the expression of a gene produces fluctuations in the concentration of the gene product. These fluctuations can interfere with optimal function or can be exploited to generate beneficial diversity between cells; gene expression noise is therefore expected to be subject to evolutionary pressure. Shifts between modes of high and low rates of transcription initiation at a promoter appear to contribute to this noise both in eukaryotes and prokaryotes. However, models invoked for eukaryotic promoter noise such as stable activation scaffolds or persistent nucleosome alterations seem unlikely to apply to prokaryotic promoters. We consider the relative importance of the steps required for transcription initiation. The 3-step transcription initiation model of McClure is extended into a mathematical model that can be used to predict consequences of additional promoter properties. We show in principle that the transcriptional bursting observed at an E. coli promoter by Golding et al. (2005) can be explained by stimulation of initiation by the negative supercoiling behind a transcribing RNA polymerase (RNAP) or by the formation of moribund or dead-end RNAP-promoter complexes. Both mechanisms are tunable by the alteration of promoter kinetics and therefore allow the optimization of promoter mediated noise.Comment: 4 figures, 1 table. Supplemental materials are also include

Regions of High Out-Of-Hospital Cardiac Arrest Incidence and Low Bystander CPR Rates in Victoria, Australia

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) remains a major public health issue and research has shown that large regional variation in outcomes exists. Of the interventions associated with survival, the provision of bystander CPR is one of the most important modifiable factors. The aim of this study is to identify census areas with high incidence of OHCA and low rates of bystander CPR in Victoria, Australia. METHODS: We conducted an observational study using prospectively collected population-based OHCA data from the state of Victoria in Australia. Using ArcGIS (ArcMap 10.0), we linked the location of the arrest using the dispatch coordinates (longitude and latitude) to Victorian Local Government Areas (LGAs). We used Bayesian hierarchical models with random effects on each LGA to provide shrunken estimates of the rates of bystander CPR and the incidence rates. RESULTS: Over the study period there were 31,019 adult OHCA attended, of which 21,436 (69.1%) cases were of presumed cardiac etiology. Significant variation in the incidence of OHCA among LGAs was observed. There was a 3 fold difference in the incidence rate between the lowest and highest LGAs, ranging from 38.5 to 115.1 cases per 100,000 person-years. The overall rate of bystander CPR for bystander witnessed OHCAs was 62.4%, with the rate increasing from 56.4% in 2008-2010 to 68.6% in 2010-2013. There was a 25.1% absolute difference in bystander CPR rates between the highest and lowest LGAs. CONCLUSION: Significant regional variation in OHCA incidence and bystander CPR rates exists throughout Victoria. Regions with high incidence and low bystander CPR participation can be identified and would make suitable targets for interventions to improve CPR participation rates

The Genome of Nectria haematococca: Contribution of Supernumerary Chromosomes to Gene Expansion

The ascomycetous fungus Nectria haematococca, (asexual name Fusarium solani), is a member of a group of >50 species known as the “Fusarium solani species complex”. Members of this complex have diverse biological properties including the ability to cause disease on >100 genera of plants and opportunistic infections in humans. The current research analyzed the most extensively studied member of this complex, N. haematococca mating population VI (MPVI). Several genes controlling the ability of individual isolates of this species to colonize specific habitats are located on supernumerary chromosomes. Optical mapping revealed that the sequenced isolate has 17 chromosomes ranging from 530 kb to 6.52 Mb and that the physical size of the genome, 54.43 Mb, and the number of predicted genes, 15,707, are among the largest reported for ascomycetes. Two classes of genes have contributed to gene expansion: specific genes that are not found in other fungi including its closest sequenced relative, Fusarium graminearum; and genes that commonly occur as single copies in other fungi but are present as multiple copies in N. haematococca MPVI. Some of these additional genes appear to have resulted from gene duplication events, while others may have been acquired through horizontal gene transfer. The supernumerary nature of three chromosomes, 14, 15, and 17, was confirmed by their absence in pulsed field gel electrophoresis experiments of some isolates and by demonstrating that these isolates lacked chromosome-specific sequences found on the ends of these chromosomes. These supernumerary chromosomes contain more repeat sequences, are enriched in unique and duplicated genes, and have a lower G+C content in comparison to the other chromosomes. Although the origin(s) of the extra genes and the supernumerary chromosomes is not known, the gene expansion and its large genome size are consistent with this species' diverse range of habitats. Furthermore, the presence of unique genes on supernumerary chromosomes might account for individual isolates having different environmental niches

Year in review in Intensive Care Medicine 2010: III. ARDS and ALI, mechanical ventilation, noninvasive ventilation, weaning, endotracheal intubation, lung ultrasound and paediatrics

SCOPUS: re.jinfo:eu-repo/semantics/publishe

Views on cardiopulmonary resuscitation among older Australians in care: A cross-sectional survey

Background: Residential aged care facilities are common locations for out-of-hospital cardiac arrests to occur, yet survival to hospital discharge is poor. Aim: This study aims to examine preferences and perceived outcomes of cardiopulmonary resuscitation among Australians receiving aged care. Methods: A brief survey was provided to 187 residential aged care facilities and 34 home care providers throughout Australia for completion by aged care residents. Respondents were asked to answer three questions about understanding and desire for cardiopulmonary resuscitation on a five-point scale (from strongly agreed to strongly disagreed). Findings: A total of 1985 residents in 163 residential aged care facilities across Australia, and 277 older Australians receiving care in the home from 24 providers responded. The majority of respondents were female (67.4%), and respondents in residential aged care facilities were significantly older (82.6%. &gt; . 75. years) than those receiving care in the home (70.4%. &gt; . 75. years) (p. &lt; . 0.001). Among 2262 respondents over 80% expressed a good understanding of cardiopulmonary resuscitation and its implications. Over half of respondents desired cardiopulmonary resuscitation if they were to experience an out-of-hospital cardiac arrest, and the desire for cardiopulmonary resuscitation was strongly associated and correlated (Pearson's R test = 0.759) with a view that they would likely fully recover. Conclusion: These findings highlight the need for older people to be better informed about cardiopulmonary resuscitation, including a clear understanding of what is involved in cardiopulmonary resuscitation and a realistic perception of outcomes