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IntroductionAcute respiratory failure requiring mechanical ventilation is a leading cause of mortality in the intensive care unit. Although single peripheral blood oxygen saturation/fraction of inspired oxygen (SpO2/FiO2) ratios of hypoxemia have been evaluated to risk-stratify patients with acute respiratory distress syndrome, the utility of longitudinal SpO2/FiO2 ratios is unknown.ObjectiveTo assess time-based SpO2/FiO2 ratios ≤ 150-SpO2/FiO2 time at risk (SF-TAR)-for predicting mortality in mechanically ventilated patients.MethodsRetrospective, observational cohort study of mechanically ventilated patients at 21 community and 2 academic hospitals. Association between the SF-TAR in the first 24 hours of ventilation and mortality was examined using multivariable logistic regression and compared with the worst recorded isolated partial pressure of arterial oxygen/fraction of inspired oxygen (P/F) ratio.ResultsIn 28,758 derivation cohort admissions, every 10% increase in SF-TAR was associated with a 24% increase in adjusted odds of hospital mortality (adjusted odds ratio = 1.24; 95% confidence interval [CI] = 1.23-1.26); a similar association was observed in validation cohorts. Discrimination for mortality modestly improved with SF-TAR (area under the receiver operating characteristic curve [AUROC] = 0.81; 95% CI = 0.81-0.82) vs the worst P/F ratio (AUROC = 0.78; 95% CI = 0.78-0.79) and worst SpO2/FiO2 ratio (AUROC = 0.79; 95% CI = 0.79-0.80). The SF-TAR in the first 6 hours offered comparable discrimination for hospital mortality (AUROC = 0.80; 95% CI = 0.79-0.80) to the 24-hour SF-TAR.ConclusionThe SF-TAR can identify ventilated patients at increased risk of death, offering modest improvements compared with single SpO2/FiO2 and P/F ratios. This longitudinal, noninvasive, and broadly generalizable tool may have particular utility for early phenotyping and risk stratification using electronic health record data in ventilated patients.

Objective: The number of office-based procedure centers with the capability of performing a wide range of endovascular procedures has substantially increased over the past decade. This shift in practice settings has occurred faster in the private sector as compared to the academic environment. The purpose of our study was to evaluate the clinical outcomes of endovascular procedures performed at a dedicated academic outpatient procedural center. Methods: We reviewed the clinical data of 400 patients who underwent 499 endovascular procedures in a universitybased, academic outpatient procedure center between November 2013 and December 2016. Outcomes analyzed included procedure-related complications, limb loss, mortality, and emergency department visits or hospital admissions that occurred within 30 days following the procedure. Results: The 400 patients had a mean age of 65 ± 13 years with slightly more females (51%; n = 203) as compared to males (49%; n = 197). Most patients (71%; 284) were Caucasian while 80 (20%) were African-Americans. Associated comorbidities included hypertension (86%), diabetes mellitus (51%), chronic kidney disease (42%), and obesity (mean body mass index of 29 ± 6). Based on anesthetic risk, most were ASA class 3 (81%), while ASA 1 and 2 comprised 17% and ASA 4 only 2%. Medicare beneficiaries accounted for 254 (64%) of our patients. Pre-operative studies included mainly duplex ultrasound (62%) and other noninvasive arterial studies (57%). The mean procedural time was 58 min (range, 7 to 200) with an overall technical success rate of 97%. There were no deaths. Complications developed in 10 patients following the 483 procedures (2.1%) being hospitalized with four of them transferred directly to the emergency room. The reasons for these hospitalizations included acute limb ischemia, arterial pseudoaneurysm, deep vein thrombosis, congestive heart failure, myocardial infarction, and lower extremity pain not vascular in origin. Financial reimbursement at the office-based center was higher than that seen with hospital-based procedures. Conclusions: Endovascular procedures performed in an academic office-based procedure center are safe and associated with good clinical outcomes. A small minority of patients have subsequent ER visits or hospital admissions. Academic institutions should consider adding an office-based procedure center based on today's competitive healthcare market. [ABSTRACT FROM AUTHOR]

In this developmental study, idiom understanding was examined in Australian students from Grades 5 and 8 (n = 50 per group; mean ages = 10:7 and 13:8, respectively). Twenty-four idioms with familiarity ratings ranging from high to low (as judged by Australian adolescents) were each presented in a brief story context. The students read each story and selected the best interpretation of the idiom from a set of four answer choices. Results indicated that performance on the task improved as a function of increasing grade level and that idiom familiarity was significantly correlated to idiom understanding for both groups of students. These results, which were consistent with a previous study of American students of comparable educational levels (Nippold & Taylor, 1995), provide further support for the 'language experience' hypothesis of figurative language development. In replicating the previous developmental study, evidence of external validity is provided. KEY WORDS: idiom understanding, cross-cultural comparison, language development, figurative language, youth

Introduction: Acute respiratory failure requiring mechanical ventilation is a leading cause of mortality in the intensive care unit. Although single peripheral blood oxygen saturation/fraction of inspired oxygen (SpO2/FiO2) ratios of hypoxemia have been evaluated to risk-stratify patients with acute respiratory distress syndrome, the utility of longitudinal SpO2/FiO2 ratios is unknown. Objective: To assess time-based SpO2/FiO2 ratios ≤ 150--Sp02/ FiO2 time at risk (SF-TAR)--for predicting mortality in mechanically ventilated patients. Methods: Retrospective, observational cohort study of mechanically ventilated patients at 21 community and 2 academic hospitals. Association between the SF-TAR in the first 24 hours of ventilation and mortality was examined using multivariable logistic regression and compared with the worst recorded isolated partial pressure of arterial oxygen/fraction of inspired oxygen (P/F) ratio. Results: In 28,758 derivation cohort admissions, every 10% increase in SF-TAR was associated with a 24% increase in adjusted odds of hospital mortality (adjusted odds ratio = 1.24; 95% confidence interval [CI] = 1.23-1.26); a similar association was observed in validation cohorts. Discrimination for mortality modestly improved with SF-TAR (area under the receiver operating characteristic curve [AUROC] = 0.81; 95% CI = 0.81-0.82) vs the worst P/F ratio (AUROC = 0.78; 95% CI = 0.78-0.79) and worst SpO2/FiO2 ratio (AUROC = 0.79; 95% CI = 0.79-0.80). The SF-TAR in the first 6 hours offered comparable discrimination for hospital mortality (AUROC = 0.80; 95% CI = 0.79-0.80) to the 24-hour SF-TAR. Conclusion: The SF-TAR can identify ventilated patients at increased risk of death, offering modest improvements compared with single SpO2/FiO2 and P/F ratios. This longitudinal, noninvasive, and broadly generalizable tool may have particular utility for early phenotyping and risk stratification using electronic health record data in ventilated patients. [ABSTRACT FROM AUTHOR]

Rhodoferax antarcticus is an Antarctic purple nonsulfur bacterium and the only characterized anoxygenic phototroph that grows best below 20 °C. We present here a high-quality draft genome of Rfx. antarcticus strain ANT.BRT, isolated from an Antarctic microbial mat. The circular chromosome (3.8 Mbp) of Rfx. antarcticus has a 59.1% guanine + cytosine (GC) content and contains 4036 open reading frames. In addition, the bacterium contains a sizable plasmid (198.6 kbp, 48.4% GC with 226 open reading frames) that comprises about 5% of the total genetic content. Surprisingly, genes encoding light-harvesting complexes 1 and 3 (LH1 and LH3), but not light-harvesting complex 2 (LH2), were identified in the photosynthesis gene cluster of the Rfx. antarcticus genome, a feature that is unique among purple phototrophs. Consistent with physiological studies that showed a strong capacity for nitrogen fixation in Rfx. antarcticus, a nitrogen fixation gene cluster encoding a molybdenum-type nitrogenase was present, but no alternative nitrogenases were identified despite the cold-active phenotype of this phototroph. Genes encoding two forms of ribulose 1,5-bisphosphate carboxylase/oxygenase were present in the Rfx. antarcticus genome, a feature that likely provides autotrophic flexibility under varying environmental conditions. Lastly, genes for assembly of both type IV pili and flagella are present, with the latter showing an unusual degree of clustering. This report represents the first genomic analysis of a psychrophilic anoxygenic phototroph and maintaining a phototrophic lifestyle in a permanently cold, yet highly variable, environment. [ABSTRACT FROM AUTHOR]

The intracellular pH of human platelets is affected by external pH and by the addition of metabolic substrates and analogues. Acetate and propionate decrease pH in a rapid concentration-dependent manner, whereas glucose decreases the internal pH at a slower rate which is independent of concentration above 0.3 mM. The mechanisms of these effects is discussed. The rate of metabolism of glucose to lactate in human platelets was strongly pH-dependent, with higher rates at more alkaline pH values. This effect was found for several different buffer systems. Addition of acetate caused an inhibition of glycolysis, whereas addition of propionate had little effect. The rate of the oxidative pentose phosphate pathway also increased with increasing pH and this pathway was inhibited by both acetate and propionate. It is proposed that the effect of acetate on glycolysis required the metabolism of the acetate, whereas the effect of both acetate and propionate on the pentose phosphate pathway are directly due to the decrease in internal pH. The oxidation of acetate to carbon dioxide showed only small pH-dependent changes in rate unless glucose was also present: glucose inhibited oxidative metabolism (the 'Crabtree Effect'), but this inhibition was only apparent at higher pH values when glycolytic rates were high. [ABSTRACT FROM AUTHOR]