Saliva urea nitrogen dipsticks to predict acute kidney injury in Malawian trauma patients

Background: Many low-resource settings have limited access to serum creatinine tests necessary for kidney disease identification. Among Malawian patients who are hospitalized after trauma, we evaluated the use of point-of-care saliva urea nitrogen (SUN) dipsticks to predict acute kidney injury (AKI). Methods: In a nested prospective cohort study, we enrolled hospitalized acute trauma patients aged ≥6 months to evaluate AKI (defined by KDIGO criteria) and the test characteristics of SUN to predict AKI. Results: Among 335 participants (approximately three-quarters able to expectorate and 34% aged ≤18 years), 12.5% (n = 42) developed AKI. At a SUN threshold of ≥40 mg/dL, a positive dipstick test was specific (99.3%) but insensitive (14.3%) in predicting AKI, with a positive predictive value of 75% and negative predictive value of 89%. At this threshold, 2.4% of participants were dipstick-positive (SUN+), and 75% of those had AKI. Reducing the SUN threshold to ≥30 mg/dL increased participants who were SUN+ to 5.0% (n = 16) but also increased the false positive rate and missed 79% (n = 33) of AKI cases. Stratified results showed better performance among adults than children and similar results when comparing participants who could and could not expectorate. There was moderate correlation between categorized BUN values and SUN (r = 0.53) but less agreement (weighted kappa 0.27; 95% CI 0.17–0.37). Conclusions: SUN dipstick testing has good specificity and negative predictive value for ruling out AKI, but poor sensitivity. We found similar results among those who could or could not expectorate a saliva sample

Succinate in dystrophic white matter: A proton magnetic resonance spectroscopy finding characteristic for complex II deficiency

A deficiency of succinate dehydrogenase is a rare cause of mitochondrial encephalomyopathy. Three patients, 2 sisters and I boy from an unrelated family, presented with symptoms and magnetic resonance imaging signs of leukoencephalopathy. Localized proton magnetic resonance spectroscopy indicated a prominent singlet at 2.40ppm in cerebral and cerebellar white matter not present in gray matter or basal ganglia. The signal was also elevated in cerebrospinal fluid and could be identified as originating from the two equivalent methylene groups of succinate. Subsequently, an isolated deficiency of complex II (succinate:ubiquinone oxidoreductase) was demonstrated in 2 patients in muscle and fibroblasts. One of the sisters died at the age of 18 months. Postmortem examination showed the neuropathological characteristics of Leigh syndrome. Her younger sister, now 12 months old, is also severely affected; the boy, now 6 years old, follows a Milder, fluctuating clinical course. Magnetic resonance spectroscopy provides a characteristic pattern in succinate dehydrogenase deficiency

Racial and health insurance disparities in pediatric acute kidney injury in the USA

Background: Acute kidney injury (AKI) significantly increases morbidity and mortality for hospitalized children, yet sociodemographic risk factors for pediatric AKI are poorly described. We examined sociodemographic differences in pediatric AKI amongst a national cohort of hospitalized children. Methods: Secondary analysis of the most recent (2012) Kids’ Inpatient Database (KID) from the Agency for Healthcare Research and Quality. Study sample weights were used to obtain national estimates of AKI (defined by administrative data). KID is a nationally representative sample of pediatric discharges throughout the USA. Linear risk regression models were used to assess the relationship between our primary exposures (race/ethnicity, health insurance, household urbanization, gender, and age) and the diagnosis of AKI, adjusting for comorbidities. Results: A total of 1,699,841 hospitalizations met our study criteria. In 2012, AKI occurred in approximately 12.3/1000 pediatric hospitalizations, which translates to almost 30,000 children nationally. Asian/Pacific Islander, African-American, and Hispanic children were at slightly increased risk for AKI compared to Caucasian children (adjusted risk difference (RD) 4.5 per 1000 hospitalizations, 95% confidence interval (CI) 2.9–6.0; 2.5/1000 hospitalizations, 95% CI 1.7–3.3; and 1.7/1000 hospitalizations, 95% CI 0.9–2.5, respectively). Uninsured children were more likely to suffer AKI compared to children with any health insurance (e.g., no insurance versus Medicaid_ adjusted RD 14.4/1000 hospitalizations, 95% CI 12.7–16.2). Based on these national estimates, one episode of AKI might be prevented if 70 (95% CI 62–79) hospitalized children without insurance were provided with Medicaid. Conclusions: Pediatric AKI occurs more frequently in racial minority and uninsured children, factors linked to lower socioeconomic status

Science for Society Workshop Summary Report

Science for Society, a workshop held at the Oak Ridge National Laboratory (ORNL) on September 27, 20111, explored ways to move Laboratory science toward use. It sought actionable recommendations. Thus the workshop focused on: (1) current practices that promote and inhibit the translation of science into use, (2) principles that could lead to improving ORNL's translational knowledge and technology transfer efforts, and (3) specific recommendations for making these principles operational. This highly interactive workshop struck a positive chord with participants, a group of 26 ORNL staff members from diverse arenas of science and technology (S and T), technology transfer, and external laboratory relations, who represented all levels of science, technology, and management. Recognizing that the transformation of fundamental principles into operational practices often follows a jagged path, the workshop sought to identify key choices that could lead to a smoother journey along this path, as well as choices that created roadblocks and bottlenecks. The workshop emphasized a portion of this pathway, largely excluding the marketplace. Participants noted that research translation includes linkages between fundamental and applied research and development (R and D), and is not restricted to uptake by manufacturers, consumers, or end users. Three crosscutting ideas encapsulate workshop participants observations: (1) ORNL should take more action to usher the translation of its S and T products toward use, so as to make a positive national and global impact and to enhance its own competitiveness in the future; (2) ORNL (and external entities such as DOE and Congress) conveys inconsistent messages with regard to the importance of research translation and application, which (a) creates confusion, (b) poses disincentives to pursue research translation, (c) imposes barriers that inhibit cross-fertilization and collaboration, and (d) diminishes the effectiveness of both the science mission and the translation of that science for use; and (3) ORNL should design its commitments and actions for helping move science from the Laboratory toward use to align with one another and should integrate them into its institutional culture in such a way as to elevate research translation and application to coequal status with scientific excellence. Participants made several actionable recommendations for enhancing research translation at ORNL, some of which were particular to specific S and T domains. Among the recommendations that participants agreed apply Lab-wide are to: align metrics and incentives with research translation goals; manage risks and conflicts of interest instead of avoiding them; and create programs (e.g., entrepreneurial leave) that promote interactions between key ORNL staff and industry in ways that complement careers at ORNL

Measles on the Edge: Coastal Heterogeneities and Infection Dynamics

Mathematical models can help elucidate the spatio-temporal dynamics of epidemics as well as the impact of control measures. The gravity model for directly transmitted diseases is currently one of the most parsimonious models for spatial epidemic spread. This model uses distance-weighted, population size-dependent coupling to estimate host movement and disease incidence in metapopulations. The model captures overall measles dynamics in terms of underlying human movement in pre-vaccination England and Wales (previously established). In spatial models, edges often present a special challenge. Therefore, to test the model's robustness, we analyzed gravity model incidence predictions for coastal cities in England and Wales. Results show that, although predictions are accurate for inland towns, they significantly underestimate coastal persistence. We examine incidence, outbreak seasonality, and public transportation records, to show that the model's inaccuracies stem from an underestimation of total contacts per individual along the coast. We rescue this predicted ‘edge effect’ by increasing coastal contacts to approximate the number of per capita inland contacts. These results illustrate the impact of ‘edge effects’ on epidemic metapopulations in general and illustrate directions for the refinement of spatiotemporal epidemic models

M1 Resonances in Unstable Magic Nuclei

Within a microscopic approach which takes into account RPA configurations, the single-particle continuum and more complex $1p1h\otimes phonon$ configurations isoscalar and isovector M1 excitations for the unstable nuclei ${56,78}$Ni and ${100,132}$Sn are calculated. For comparison, the experimentally known M1 excitations in ${40}$Ca and $^{208}$Pb have also been calculated. In the latter nuclei good agreement in the centroid energy, the total transition strength and the resonance width is obtained. With the same parameters we predict the magnetic excitations for the unstable nuclei. The strength is sufficiently concentrated to be measurable in radioactive beam experiments. New features are found for the very neutron rich nucleus ${78}$Ni and the neutron deficient nucleus ${100}$Sn.Comment: 17 pages (LATEX), 12 figures (available from the authors), KFA-IKP(TH)-1993-0

Adaptive landscape genetics and malaria across divergent island bird populations

Environmental conditions play a major role in shaping the spatial distributions of pathogens, which in turn can drive local adaptation and divergence in host genetic diversity. Haemosporidians, such as Plasmodium (malaria), are a strong selective force, impacting survival and fitness of hosts, with geographic distributions largely determined by habitat suitability for their insect vectors. Here, we have tested whether patterns of fine‐scale local adaptation to malaria are replicated across discrete, ecologically differing island populations of Berthelot's pipits Anthus berthelotii . We sequenced TLR4, an innate immunity gene that is potentially under positive selection in Berthelot's pipits, and two SNPs previously identified as being associated with malaria infection in a genome‐wide association study (GWAS) in Berthelot's pipits in the Canary Islands. We determined the environmental predictors of malaria infection, using these to estimate variation in malaria risk on Porto Santo, and found some congruence with previously identified environmental risk factors on Tenerife. We also found a negative association between malaria infection and a TLR4 variant in Tenerife. In contrast, one of the GWAS SNPs showed an association with malaria risk in Porto Santo, but in the opposite direction to that found in the Canary Islands GWAS. Together, these findings suggest that disease‐driven local adaptation may be an important factor in shaping variation among island populations

Effects of Noise on Ecological Invasion Processes: Bacteriophage-mediated Competition in Bacteria

Pathogen-mediated competition, through which an invasive species carrying and transmitting a pathogen can be a superior competitor to a more vulnerable resident species, is one of the principle driving forces influencing biodiversity in nature. Using an experimental system of bacteriophage-mediated competition in bacterial populations and a deterministic model, we have shown in [Joo et al 2005] that the competitive advantage conferred by the phage depends only on the relative phage pathology and is independent of the initial phage concentration and other phage and host parameters such as the infection-causing contact rate, the spontaneous and infection-induced lysis rates, and the phage burst size. Here we investigate the effects of stochastic fluctuations on bacterial invasion facilitated by bacteriophage, and examine the validity of the deterministic approach. We use both numerical and analytical methods of stochastic processes to identify the source of noise and assess its magnitude. We show that the conclusions obtained from the deterministic model are robust against stochastic fluctuations, yet deviations become prominently large when the phage are more pathological to the invading bacterial strain.Comment: 39 pages, 7 figure