Abstract
Depending upon the properties of their compact remnants and the physics included in the models, simulations of neutron star mergers can produce a broad range of ejecta properties. The ...characteristics of this ejecta, in turn, define the kilonova emission. To explore the effect of ejecta properties, we present a grid of two-component 2D axisymmetric kilonova simulations that vary mass, velocity, morphology, and composition. The masses and velocities of each component vary, respectively, from 0.001 to 0.1
M
⊙
and 0.05 to 0.3
c
, covering much of the range of results from the neutron star merger literature. The set of 900 models is constrained to have a toroidal low electron fraction (
Y
e
) ejecta with a robust
r
-process composition and either a spherical or lobed high-
Y
e
ejecta with two possible compositions. We simulate these models with the Monte Carlo radiative transfer code
SuperNu
using a full suite of lanthanide and fourth-row element opacities. We examine the trends of these models with parameter variation, show how they can be used with statistical tools, and compare the model light curves and spectra to those of AT2017gfo, the electromagnetic counterpart of GW170817.
Microparticles in Health and Disease Herring, J.M.; McMichael, M.A.; Smith, S.A.
Journal of veterinary internal medicine,
September/October 2013, Letnik:
27, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Microparticles (MPs), small membrane‐derived vesicles, are derived from many cell types and released into the circulation. Microparticles can express antigens, and contain cell surface proteins, ...cytoplasmic contents, and nuclear components from their cell of origin that determines their composition, characterization, and transfer of biologic information. Certain prompts for this release include shear stress, complement activation, proapoptotic stimulation, cellular damage, or agonist interaction with cell surface receptors. Release can be physiologic or pathologic and is associated with proinflammatory and procoagulant effects and has been implicated in thrombotic states. Microparticles also contribute to systemic inflammation and cardiovascular, hematologic, and oncologic disease states. The study of MPs in human medicine is rapidly advancing and extends into the physiology of health, the pathophysiology of disease, and the role of MPs in transfusion medicine. In veterinary medicine, published work on MPs has been limited to the area of inherited disorders, blood storage, and leukoreduction (LR). Microparticle research is still in its infancy, and this review should be seen as a snapshot of what is currently known. As research continues important limitations, including variations in preanalytic variables such as collection, storage, or centrifugation, and limitations of quantitation are coming to the forefront. Correlation of quantitation of MPs with assays of activity will hopefully shed light on the true nature of MPs in health and disease. This review will focus on the role of cellular exocytic vesiculation in health, disease, and transfusion medicine.
Context:
Randomized controlled trials in nonalcoholic fatty liver disease (NAFLD) have shown that regular exercise, even without calorie restriction, reduces liver steatosis. A previous study has ...shown that 16 weeks of supervised exercise training in NAFLD did not affect total very low-density lipoprotein (VLDL) kinetics.
Objective:
The objective of the study was to determine the effect of exercise training on intrahepatocellular fat (IHCL) and the kinetics of large triglyceride (TG)-rich VLDL1 and smaller denser VLDL2, which has a lower TG content.
Design:
This was a 16-week randomized controlled trial.
Patients:
A total of 27 sedentary patients with NAFLD participated in the trial.
Intervention:
The intervention was composed of supervised exercise with moderate-intensity aerobic exercise or conventional lifestyle advice (control).
Main Outcome:
VLDL1 and VLDL2-TG and apolipoprotein B (apoB) kinetics were investigated using stable isotopes before and after the intervention.
Results:
In the exercise group, maximal oxygen uptake increased by 31% ± 6% (mean ± SEM) and IHCL decreased from 19.6% (14.8%, 30.0%) to 8.9% (5.4%, 17.3%) (median interquartile range) with no significant change in maximal oxygen uptake or IHCL in the control group (change between groups, P < .001 and P = .02, respectively). Exercise training increased VLDL1-TG and apoB fractional catabolic rates, a measure of clearance, (change between groups, P = .02 and P = .01, respectively), and VLDL1-apoB production rate (change between groups, P = .006), with no change in VLDL1-TG production rate. Plasma TG did not change in either group.
Conclusion:
An increased clearance of VLDL1 may contribute to the significant decrease in liver fat after 16 weeks of exercise in NAFLD. A longer duration or higher-intensity exercise interventions may be needed to lower the plasma TG and VLDL production rate.
A 16-week exercise improved fitness and reduced liver fat by 50% in men with NAFLD and increased clearance of both VLDL1 TG and apoB. However the liver continued to export large amounts of VLDL-TG.
Objective
To estimate the association between lipoprotein particle concentrations in pregnancy and gestational age at delivery.
Design
Prospective cohort study.
Setting
The study was conducted in the ...USA at the University of North Carolina.
Population
We assessed 715 women enrolled in the Pregnancy, Infection, and Nutrition study from 2001 to 2005.
Methods
Fasting blood was collected at two time points (<20 and 24–29 weeks of gestation). Nuclear magnetic resonance (NMR) quantified lipoprotein particle concentrations low‐density lipoprotein (LDL), high‐density lipoprotein (HDL), very‐low density lipoprotein (VLDL) and 10 subclasses of lipoproteins. Concentrations were assessed as continuous measures, with the exception of medium HDL which was classified as any or no detectable level, given its distribution. Cox proportional hazards models estimated hazard ratios (HR) for gestational age at delivery adjusting for covariates.
Main outcome measures
Gestational age at delivery, preterm birth (<37 weeks of gestation), and spontaneous preterm birth.
Results
At <20 weeks of gestation, three lipoproteins were associated with later gestational ages at delivery large LDLNMR (HR 0.78, 95% CI 0.64–0.96), total VLDLNMR (HR 0.77, 95% CI 0.61–0.98), and small VLDLNMR (HR 0.78, 95% CI 0.62–0.98, whereas large VLDLNMR (HR 1.19, 95% CI 1.01–1.41) was associated with a greater hazard of earlier delivery. At 24–28 weeks of gestation, average VLDLNMR (HR 1.25, 95% CI 1.03–1.51) and a detectable level of medium HDLNMR (HR 1.90, 95% CI 1.19–3.02) were associated with earlier gestational ages at delivery.
Conclusion
In this sample of pregnant women, particle concentrations of VLDLNMR, LDLNMR, IDLNMR, and HDLNMR were each independently associated with gestational age at delivery for all deliveries or spontaneous deliveries <37 weeks of gestation. These findings may help formulate hypotheses for future studies of the complex relationship between maternal lipoproteins and preterm birth.
Tweetable
Nuclear magnetic resonance spectroscopy may identify lipoprotein particles associated with preterm delivery.
Tweetable
Nuclear magnetic resonance spectroscopy may identify lipoprotein particles associated with preterm delivery.
•Coulomb delocalization represents the radial extent of forces between a primary electron and atomic electrons within a thin specimen.•It also represents the specimen region over which information ...about the specimen is integrated, and the region over which energy is initially deposited.•It does not represent the region over which inelastic scattering takes place, or the region from which scattered electrons appear to originate.•The Coulomb point spread function cannot be measured as a broadening of the inelastic image of a small probe.
An interpretation of Coulomb delocalization, which limits the spatial resolution of inelastic TEM or STEM images, is given. We conclude that the corresponding point spread function cannot be measured as a broadening of a STEM probe.
Summary Background Despite preventive vaccines for oncogenic human papillomaviruses (HPVs), cervical intraepithelial neoplasia (CIN) is common, and current treatments are ablative and can lead to ...long-term reproductive morbidity. We assessed whether VGX-3100, synthetic plasmids targeting HPV-16 and HPV-18 E6 and E7 proteins, delivered by electroporation, would cause histopathological regression in women with CIN2/3. Methods Efficacy, safety, and immunogenicity of VGX-3100 were assessed in CIN2/3 associated with HPV-16 and HPV-18, in a randomised, double-blind, placebo-controlled phase 2b study. Patients from 36 academic and private gynaecology practices in seven countries were randomised (3:1) to receive 6 mg VGX-3100 or placebo (1 mL), given intramuscularly at 0, 4, and 12 weeks. Randomisation was stratified by age (<25 vs ≥25 years) and CIN2 versus CIN3 by computer-generated allocation sequence (block size 4). Funder and site personnel, participants, and pathologists were masked to treatment. The primary efficacy endpoint was regression to CIN1 or normal pathology 36 weeks after the first dose. Per-protocol and modified intention-to-treat analyses were based on patients receiving three doses without protocol violations, and on patients receiving at least one dose, respectively. The safety population included all patients who received at least one dose. The trial is registered at ClinicalTrials.gov (number NCT01304524 ) and EudraCT (number 2012-001334-33). Findings Between Oct 19, 2011, and July 30, 2013, 167 patients received either VGX-3100 (n=125) or placebo (n=42). In the per-protocol analysis 53 (49·5%) of 107 VGX-3100 recipients and 11 (30·6%) of 36 placebo recipients had histopathological regression (percentage point difference 19·0 95% CI 1·4–36·6; p=0·034). In the modified intention-to-treat analysis 55 (48·2%) of 114 VGX-3100 recipients and 12 (30·0%) of 40 placebo recipients had histopathological regression (percentage point difference 18·2 95% CI 1·3–34·4; p=0·034). Injection-site reactions occurred in most patients, but only erythema was significantly more common in the VGX-3100 group (98/125, 78·4%) than in the placebo group (24/42, 57·1%; percentage point difference 21·3 95% CI 5·3–37·8; p=0·007). Interpretation VGX-3100 is the first therapeutic vaccine to show efficacy against CIN2/3 associated with HPV-16 and HPV-18. VGX-3100 could present a non-surgical therapeutic option for CIN2/3, changing the treatment outlook for this common disease. Funding Inovio Pharmaceuticals.
Adolescent pregnancy contributes to accelerated trajectories of adiposity and cardiometabolic diseases. Two potentially low-cost prevention strategies include promoting physical activity (PA) and ...limiting television (TV) viewing. Few studies have explored these behavior patterns in perinatal adolescents. This study sought to characterize PA and TV viewing in a socioeconomically disadvantaged perinatal adolescent population.
A cross-sectional, retrospective, 10-item survey was used to explore behavior patterns in 79 predominantly Black (86%) postpartum adolescents. Main Outcome Measures: Outcomes included self-reported changes in PA from pre-pregnancy through pregnancy, and 7-day recall of PA and TV viewing in postpartum.
The majority of adolescents (66%) reported being active on ≥3 days/week in pre-pregnancy; however, many reported low PA (≤2 days/wk) in their first (59%), second (66%), and third (54%) trimesters. Adolescents who reported being active on ≥5 days/wk in pre-pregnancy (19%) experienced first trimester PA decline, which subsequently plateaued. This group remained the most active throughout pregnancy. In postpartum, over half (54%) of all adolescents reported low PA and irrespective of PA, spent considerable time watching TV (median = 1680.0 minutes, inerquartile range = 2940).
Interventions promoting PA coupled with reducing TV viewing during pregnancy and in postpartum may benefit perinatal adolescents. The findings from this study suggest that PA history is a predictor of gestational PA, and low PA and high TV viewing in postpartum underscore the need for behavioral intervention. Conducting a brief assessment of PA history in early gestation may offer important insight.
Biodiesel is an oxygenated diesel fuel made from vegetable oils and animal fats by conversion of the triglyceride fats to esters via transesterification. In this study we examined biodiesels produced ...from a variety of real-world feedstocks as well as pure (technical grade) fatty acid methyl and ethyl esters for emissions performance in a heavy-duty truck engine. The objective was to understand the impact of biodiesel chemical structure, specifically fatty acid chain length and number of double bonds, on emissions of NOx and particulate matter (PM). A group of seven biodiesels produced from real-world feedstocks and 14 produced from pure fatty acids were tested in a heavy-duty truck engine using the U.S. heavy-duty federal test procedure (transient test). It was found that the molecular structure of biodiesel can have a substantial impact on emissions. The properties of density, cetane number, and iodine number were found to be highly correlated with one another. For neat biodiesels, PM emissions were essentially constant at about 0.07 g/bhp-h for all biodiesels as long as density was less than 0.89 g/cm3 or cetane number was greater than about 45. NOx emissions increased with increasing fuel density or decreasing fuel cetane number. Increasing the number of double bonds, quantified as iodine number, correlated with increasing emissions of NOx. Thus the increased NOx observed for some fuels cannot be explained by the NOx/PM tradeoff and is therefore not driven by thermal NO formation. For fully saturated fatty acid chains the NOx emission increased with decreasing chain length for tests using 18, 16, and 12 carbon chain molecules. Additionally, there was no significant difference in NOx or PM emissions for the methyl and ethyl esters of identical fatty acids.
Background
The molecular changes that occur in the stomach that are associated with idiopathic gastroparesis are poorly described. The aim of this study was to use quantitative analysis of mRNA ...expression to identify changes in mRNAs encoding proteins required for the normal motility functions of the stomach.
Methods
Full‐thickness stomach biopsy samples were collected from non‐diabetic control subjects who exhibited no symptoms of gastroparesis and from patients with idiopathic gastroparesis. mRNA was isolated from the muscularis externa and mRNA expression levels were determined by quantitative reverse transcriptase (RT)‐PCR.
Key Results
Smooth muscle tissue from idiopathic gastroparesis patients had decreased expression of mRNAs encoding several contractile proteins, such as MYH11 and MYLK1. Conversely, there was no significant change in mRNAs characteristic of interstitial cells of Cajal (ICCs) such as KIT or ANO1. There was also a significant decrease in mRNA‐encoding platelet‐derived growth factor receptor α (PDGFRα) and its ligand PDGFB and in Heme oxygenase 1 in idiopathic gastroparesis subjects. In contrast, there was a small increase in mRNA characteristic of neurons. Although there was not an overall change in KIT expression in gastroparesis patients, KIT expression showed a significant correlation with gastric emptying whereas changes in MYLK1, ANO1 and PDGFRα showed weak correlations to the fullness/satiety subscore of patient assessment of upper gastrointestinal disorder‐symptom severity index scores.
Conclusions and Inferences:
Our findings suggest that idiopathic gastroparesis is associated with altered smooth muscle cell contractile protein expression and loss of PDGFRα+ cells without a significant change in ICCs.
qRT‐PCR analysis revealed that smooth muscle tissue from idiopathic gastroparesis patients had decreased expression of mRNAs encoding several contractile and regulatory proteins, PDGFRalpha and its ligand PDGFB and Heme oxygenase 1. Conversely, there was no significant change in mRNAs characteristic of interstitial cells of Cajal (ICCs), such as KIT or ANO1. These findings suggest that idiopathic gastroparesis is most commonly associated with transcriptional changes that are indicative of altered smooth muscle cells and PDGFRalpha positive fibroblast cells rather than ICCs.
PDF
