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It was not accidental that in February 1861 Jefferson Davis, a prominent slaveholder from Mississippi, was inaugurated at Montgomery, Alabama, as the new president of the Confederate States of America. Both states had long been at the center of antebellum political power, wielding the stunning influence wrought by cotton and slavery. While South Carolina led the secessionist impulse, the emerging Confederate project would almost certainly have faltered without the crucial support of the Deep South. The Lower South states that seceded in the winter of 1860–1 commanded great political and sectional influence, shaping how and when the incipient slaveholding republic would be formed. But with the advent of war in April 1861, military thinkers considered Mississippi and Alabama the constituent states of the Deep South, judging other parts of the rebellious South in wholly different strategic terms. Mississippi and Alabama indeed played central roles in the formation of the world’s largest slaveholding republic; they would accordingly feel the hard hand of war in response to that decision. Although both states did not incur the same kind of invasions and wartime scarring endured by Virginia, Tennessee, and Georgia, the Deep South functioned as a testing ground for some of the Civil War’s most transformative events, rooted almost entirely in the tense nature of civilian–military relations.
Building on the synthesis of carbon reservoirs in Earth's subsurface, this chapter focuses on the forms, cycling, and fate of the carbon supporting microbial life in the terrestrial and marine subsurface. As the subsurface is estimated to host a vast reservoir of life on Earth, identifying the carbon compounds that life uses for energy and growth is key to understanding ecosystem functioning in the past and at present, and also for extrapolating these findings to the search for life in the universe. This chapter highlights advances in quantifying small carbon compounds, measuring rates of carbon turnover, and the fate of carbon in the deep biosphere.
Apolipoprotein E (APOE) E4 is the main genetic risk factor for Alzheimer’s disease (AD). Due to the consistent association, there is interest as to whether E4 influences the risk of other neurodegenerative diseases. Further, there is a constant search for other genetic biomarkers contributing to these phenotypes, such as microtubule-associated protein tau (MAPT) haplotypes. Here, participants from the Ontario Neurodegenerative Disease Research Initiative were genotyped to investigate whether the APOE E4 allele or MAPT H1 haplotype are associated with five neurodegenerative diseases: (1) AD and mild cognitive impairment (MCI), (2) amyotrophic lateral sclerosis, (3) frontotemporal dementia (FTD), (4) Parkinson’s disease, and (5) vascular cognitive impairment.
Genotypes were defined for their respective APOE allele and MAPT haplotype calls for each participant, and logistic regression analyses were performed to identify the associations with the presentations of neurodegenerative diseases.
Our work confirmed the association of the E4 allele with a dose-dependent increased presentation of AD, and an association between the E4 allele alone and MCI; however, the other four diseases were not associated with E4. Further, the APOE E2 allele was associated with decreased presentation of both AD and MCI. No associations were identified between MAPT haplotype and the neurodegenerative disease cohorts; but following subtyping of the FTD cohort, the H1 haplotype was significantly associated with progressive supranuclear palsy.
This is the first study to concurrently analyze the association of APOE isoforms and MAPT haplotypes with five neurodegenerative diseases using consistent enrollment criteria and broad phenotypic analysis.
The root causes of the present instability of the international economic order are difficult to diagnose. For some, the core problem is the radically unequal distribution of the gains and losses associated with the recent period of globalization: existing economic institutions and structures have been challenged as those who have lost (or gained little) from globalization withdraw their support from a system that appears not to work to their advantage. For others, the primary explanation is the relative erosion of US global economic hegemony, which has both left the United States less willing to act as the guarantor of the system in its present form and given rise to increasingly urgent efforts to reshape the system in ways that may more reliably sustain existing distributions of economic power. And for yet others, the present system is under attack because it has failed to deliver on its promise of economic self-determination at the national level, as political communities feel their futures constrained and directed by global rules, institutions and logics that seem out of their immediate control.
This short essay starts with the claim that the current period of instability is also the result, in part, of far-reaching changes to the institutional underpinnings of the global economy that occurred during the last quarter century or so after the end of the Cold War. At the time, the years following the collapse of communism seemed to herald a radical reduction in the global economy's institutional diversity as states throughout the former Second and Third worlds converged toward a single model of market capitalism. But the reality has proved more complicated: the national marketization projects initiated during this period have each evolved according to different dynamics, resulting in the emergence of a variety of new and heterodox market forms in different countries and regions of the world. “Every transition to capitalism,” it has been observed, “produced a new variety of capitalism.” These economies have become more deeply integrated with global markets, reopening one of the fundamental questions the postwar international economic order has always faced concerning the legitimate range of institutional diversity fairly permitted in global competition conditions: At what point do heterodox market forms cease to constitute legitimate experimentation and become a form of “cheating” on the terms of fair competition in international trade?
Sex-specific diagnostic cut-offs may improve the test characteristics of high-sensitivity troponin assays for the diagnosis of myocardial infarction (MI). The objective of this study was to quantify test characteristics of sex-specific cut-offs of a single, high-sensitivity cardiac troponin T (hs-cTnT) assay for 7-day MI in patients with chest pain.
This observational cohort study included consecutive emergency department (ED) patients with suspected cardiac chest pain from four Canadian EDs who had an hs-cTnT assay performed within 60 minutes of ED arrival. The primary outcome was MI at 7 days. We quantified test characteristics (sensitivity, negative predictive value [NPV], likelihood ratios and proportion of patients ruled out) for multiple combinations of sex-specific, rule-out cut-offs. We calculated the net reclassification index compared to universal rule-out cut-offs.
In 7,130 patients (3,931 men and 3,199 women), the 7-day MI incidence was 7.38% among men and 3.78% among women. Optimal sex-specific cut-offs (<8 ng/L for men and <7 ng/L for women) had a 98.5% sensitivity for MI and ruled out MI in 55.8% of patients. This would enable an absolute increase in the proportion of patients who were able to be ruled out with a single hs-cTnT of 13.2% to 22.2%, depending on the universal rule-out concentration used as a comparator.
Sex-specific hs-cTnT cut-offs for ruling out MI at ED arrival may improve classification performance, enabling more patients to be safely ruled out at ED arrival. However, differences between sex-specific and universal cut-off concentrations are within the variation of the assay, limiting the clinical utility of this approach. These findings should be confirmed in other data sets.
D-dimer testing is an important component of the workup for pulmonary embolism (PE). However, age-related increases in D-dimer concentrations result in false positives in older adults, leading to potentially unnecessary imaging utilization. The objective of this study was to quantify the test characteristics of an age-adjusted D-dimer cut-off for ruling out PE in older patients investigated in actual clinical practice.
This observational study used administrative data from four emergency departments from July 2013 to January 2015. Eligible patients were ages 50 and older with symptoms of PE who underwent D-dimer testing. The primary outcome was 30-day diagnosis of PE, confirmed by imaging reports. Test characteristics of the D-dimer assay were calculated using the standard reference value (500 ng/ml), the local reference value (470 ng/ml), and an age-adjusted threshold (10 ng/ml × patient’s age).
This cohort includes 6,655 patients ages 50 and older undergoing D-dimer testing for a possible PE. Of these, 246 (3.7%) were diagnosed with PE. Age-adjusted D-dimer cut-offs were more specific than standard cut-offs (75.4% v. 63.8%) but less sensitive (90.3% v. 97.2%). The false-negative risk in this population was 0.49% using age-adjusted D-dimer cut-offs compared with 0.15% with traditional cut-offs.
Age-adjusted D-dimer cut-offs are substantially more specific than traditional cut-offs and may reduce CT utilization among older patients with suspected PE. We observed a loss of sensitivity, with an increased risk of false-negatives, using age-adjusted cut-offs. We encourage further evaluation of the safety and accuracy of age-adjusted D-dimer cut-offs in actual clinical practice.
OBJECTIVES/SPECIFIC AIMS: The purpose of this study is to use the baboon as a novel animal model for breath research and to identify and characterize baboon breath metabolites that reflect cardiometabolic function to inform us in the development of a noninvasive, cost-effective, and repeatable point-of-care diagnostic breath test. METHODS/STUDY POPULATION: Blood and urine was collected from control and IUGR at the approximate age of 3.5 years. Both groups were then placed on a high fat, high sugar, high salt diet for 7 weeks, after which blood, urine, and breath were collected. The breath samples were then subjected to comprehensive, 2-dimensional gas chromatography coupled with time-of-flight mass spectrometry. Using ChromaTOF software, breath VOCs were identified with at least an 80% spectral match against the National Institute of Standards and Technology (NIST) chemical reference library. The raw data were then statistically analyzed using MetaboAnalyst. We then interrogated multiple online databases to characterize and identify the role of VOCs that were present in both control and IUGR groups. RESULTS/ANTICIPATED RESULTS: Preliminary analyses of the breath VOCs indicate differences in expression between sexes and in control Versus IUGR groups. These results indicate unique “breath signatures.” Further analysis of the breath VOCs reveals the presence of metabolites that are involved in β-oxidation and oxidative stress pathways. DISCUSSION/SIGNIFICANCE OF IMPACT: This breath study, a first of its kind, will develop the baboon as a superior animal model for breath biomarker research. Our observed unique “breath signatures” indicate changes in lipid metabolism and oxidative stress pathways, which we hypothesize are the early metabolic changes at the cellular level that are not yet reflected in clinical lab measures. Future directions include analyzing breath VOCs that did not meet 80% spectral match, validation using SPME technology and commercial standards, and initiating a human pilot study in clinically obese, at-risk children in collaboration with physicians at the Children’s Hospital of San Antonio to develop a noninvasive, cost-effective, rapid, and repeatable point-of-care diagnostic breath test.
Although procedural sedation for cardioversion is a common event in emergency departments (EDs), there is limited evidence surrounding medication choices. We sought to evaluate geographic and temporal variation in sedative choice at multiple Canadian sites, and to estimate the risk of adverse events due to sedative choice.
This is a secondary analysis of one health records review, the Recent Onset Atrial Fibrillation or Flutter-0 (RAFF-0 [n=420, 2008]) and one prospective cohort study, the Recent Onset Atrial Fibrillation or Flutter-1 (RAFF-1 [n=565, 2010 – 2012]) at eight and six Canadian EDs, respectively. Sedative choices within and among EDs were quantified, and the risk of adverse events was examined with adjusted and unadjusted comparisons of sedative regimes.
In RAFF-0 and RAFF-1, the combination of propofol and fentanyl was most popular (63.8% and 52.7%) followed by propofol alone (27.9% and 37.3%). There were substantially more adverse events in the RAFF-0 data set (13.5%) versus RAFF-1 (3.3%). In both data sets, the combination of propofol/fentanyl was not associated with increased adverse event risk compared to propofol alone.
There is marked variability in procedural sedation medication choice for a direct current cardioversion in Canadian EDs, with increased use of propofol alone as a sedation agent over time. The risk of adverse events from procedural sedation during cardioversion is low but not insignificant. We did not identify an increased risk of adverse events with the addition of fentanyl as an adjunctive analgesic to propofol.