The Science Performance of JWST as Characterized in Commissioning

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures; https://iopscience.iop.org/article/10.1088/1538-3873/acb29

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Impaired HDL Metabolism Links GlycA, A Novel Inflammatory Marker, with Incident Cardiovascular Events

High-density lipoproteins (HDL) exert anti-atherosclerotic effects via reverse cholesterol transport, yet this salutary property is impaired in the setting of inflammation. GlycA, a novel integrated glycosylation marker of five acute phase reactants, is linked to cardiovascular (CV) events. We assessed the hypothesis that GlycA is associated with measures of impaired HDL function and that dysfunctional HDL may contribute to the association between GlycA and incident CV events. Baseline measurements of HDL cholesterol (HDL-C), HDL particle concentration (HDL-P), apoliprotein A1 (Apo A1), cholesterol efflux capacity, GlycA and high-sensitivity C-reactive protein (hs-CRP) were obtained from the Dallas Heart Study, a multi-ethnic cohort of 2643 adults (median 43 years old; 56% women, 50% black) without cardiovascular disease (CVD). GlycA was derived from nuclear magnetic resonance imaging. Participants were followed for first nonfatal MI, nonfatal stroke, coronary revascularization, or CV death over a median of 12.4 years (n = 197). The correlation between GlycA and hs-CRP was 0.58 (p < 0.0001). In multivariate models with HDL-C, GlycA was directly associated with HDL-P and Apo A1 and inversely associated with cholesterol efflux (standardized beta estimates: 0.08, 0.29, -0.06, respectively; all p ≤ 0.0004) GlycA was directly associated with incident CV events (adjusted hazard ratio (HR) for Q4 vs. Q1: 3.33, 95% confidence interval (CI) 1.99, 5.57). Adjustment for cholesterol efflux mildly attenuated this association (HR for Q4 vs. Q1: 3.00, 95% CI 1.75 to 5.13). In a multi-ethnic cohort, worsening inflammation, as reflected by higher GlycA levels, is associated with higher HDL-P and lower cholesterol efflux. Impaired cholesterol efflux likely explains some of the association between GlycA and incident CV events. Further studies are warranted to investigate the impact of inflammation on HDL function and CV disease

Impaired HDL Metabolism Links GlycA, A Novel Inflammatory Marker, with Incident Cardiovascular Events.

High-density lipoproteins (HDL) exert anti-atherosclerotic effects via reverse cholesterol transport, yet this salutary property is impaired in the setting of inflammation. GlycA, a novel integrated glycosylation marker of five acute phase reactants, is linked to cardiovascular (CV) events. We assessed the hypothesis that GlycA is associated with measures of impaired HDL function and that dysfunctional HDL may contribute to the association between GlycA and incident CV events. Baseline measurements of HDL cholesterol (HDL-C), HDL particle concentration (HDL-P), apoliprotein A1 (Apo A1), cholesterol efflux capacity, GlycA and high-sensitivity C-reactive protein (hs-CRP) were obtained from the Dallas Heart Study, a multi-ethnic cohort of 2643 adults (median 43 years old; 56% women, 50% black) without cardiovascular disease (CVD). GlycA was derived from nuclear magnetic resonance imaging. Participants were followed for first nonfatal MI, nonfatal stroke, coronary revascularization, or CV death over a median of 12.4 years (n = 197). The correlation between GlycA and hs-CRP was 0.58 (p \u3c 0.0001). In multivariate models with HDL-C, GlycA was directly associated with HDL-P and Apo A1 and inversely associated with cholesterol efflux (standardized beta estimates: 0.08, 0.29, -0.06, respectively; all p ≤ 0.0004) GlycA was directly associated with incident CV events (adjusted hazard ratio (HR) for Q4 vs. Q1: 3.33, 95% confidence interval (CI) 1.99, 5.57). Adjustment for cholesterol efflux mildly attenuated this association (HR for Q4 vs. Q1: 3.00, 95% CI 1.75 to 5.13). In a multi-ethnic cohort, worsening inflammation, as reflected by higher GlycA levels, is associated with higher HDL-P and lower cholesterol efflux. Impaired cholesterol efflux likely explains some of the association between GlycA and incident CV events. Further studies are warranted to investigate the impact of inflammation on HDL function and CV disease

Abstract 15297: High-Density Lipoprotein Function Associates With GlycA, a Novel Inflammation Marker, but Does Not Explain the Association Between GlycA and Incident Cardiovascular Events

Background: High-density lipoproteins (HDL) exert anti-atherosclerotic effects via reverse cholesterol transport, yet this process is impaired in the setting of inflammation. GlycA, a novel integrated glycosylation marker of five acute phase reactants, is linked to CV events. We assessed the hypothesis that GlycA is associated with impaired HDL function measures and that the association between GlycA and incident CV events is partially explained by dysfunctional HDL. Methods: Baseline measurements of HDL cholesterol (HDL-C), HDL particle concentration (HDL-P), and cholesterol efflux capacity were obtained from the Dallas Heart Study, a multi-ethnic cohort of 2225 adults without CVD. GlycA was derived from NMR spectral features. The primary end point was first nonfatal MI, nonfatal stroke, coronary revascularization, or CV death over a median of 11.4 years (N=171). Results: Median age was 43 with 56% women and 47% blacks. The correlation between GlycA and hs-CRP was 0.54 (p\u3c0.0001). HDL-P, HDL-C, and cholesterol efflux were inversely associated with GlycA when adjusted for traditional risk factors, hs-CRP, and all HDL measures (standardized beta estimates: -0.10, -0.20, and -0.06, respectively; all p\u3c0.0002). In Cox proportional hazards models adjusted for risk factors, GlycA was directly associated with incident CV events (HR for Q4 vs. Q1: 2.25, 95% CI 1.33 to 3.82). Further adjustment for cholesterol efflux did not attenuate this association (HR for Q4 vs. Q1: 2.13, 95% CI 1.25 to 3.63), while cholesterol efflux remained inversely associated (HR for Q4 vs. Q1: 0.59, 95% CI 0.39 to 0.89) with the primary outcome (Figure). Conclusions: Worsening inflammation as reflected by higher GlycA levels is associated with lower HDL-C, HDL-P, and cholesterol efflux. Cholesterol efflux does not appear to mediate the association between GlycA and incident CV events. Further studies are warranted to investigate the impact of inflammation on HDL function and CV disease. Download figure Footnotes Author Disclosures: K.A. Riggs: None. P.H. Joshi: Consultant/Advisory Board; Modest; Regeneron. A. Khera: None. K. Singh: None. O. Akinmolayemi: None. C.R. Ayers: None. A. Rohatgi: Research Grant; Significant; Merck. Other Research Support; Modest; NIH, AHA. Consultant/Advisory Board; Modest; Merck, CSL Limited, HDL Diagnostics, Cleveland HeartLabs

Acute Exenatide Therapy Attenuates Postprandial Vasodilation in Humans with Prediabetes: A Randomized Controlled Trial.

Background: The state of prediabetes comprises atherosclerotic changes leading to decreased vascular function in humans. This study examined the effects on incretin mimetics on vascular physiology in the prediabetic postprandial state. Methods: Fifteen obese adults with prediabetes participated in a randomized, crossover, double-blinded trial comparing the postprandial effects of exenatide, saxagliptin, and placebo on peripheral vasodilation. All studies utilized a standardized high-fat meal. Resting and peak forearm blood flow (FBF) were measured via strain gauge venous occlusion plethysmography, and makers of vascular dysfunction were measured in plasma. Results: Exenatide attenuated resting FBF at 3 hr (P = 0.003) and 6 hr (P = 0.056) postmeal, compared to placebo. Nonsignificant reductions in resting FBF were observed between saxagliptin and placebo at the same time points. No group differences were observed for peak FBF, plasma nitrotyrosine, and plasma 8-iso-prostaglandin F2alpha. A transient increase in plasma triglyceride was abated in the exenatide group, when compared to saxagliptin and placebo groups. Only exenatide group showed no significant upsurge in plasma insulin. Plasma-free fatty acids significantly declined in all three groups, although less markedly for exenatide. Postmeal glucose increased at 2 hr with placebo and saxagliptin, but simultaneously decreased with exenatide. Conclusions: Acute treatment with exenatide blunted the postprandial vasodilatory effect of a high-fat meal in prediabetes. Exenatides acute effects derived primarily from multiple endothelium-independent processes. Trial Registration Number: NCT02104739

Anti-diabetic effects of GLP1 analogs are mediated by thermogenic interleukin-6 signaling in adipocytes.

Mechanisms underlying anti-diabetic effects of GLP1 analogs remain incompletely understood. We observed that in prediabetic humans exenatide treatment acutely induces interleukin-6 (IL-6) secretion by monocytes and IL-6 in systemic circulation. We hypothesized that GLP1 analogs signal through IL-6 in adipose tissue (AT) and used the mouse model to test if IL-6 receptor (IL-6R) signaling underlies the effects of the GLP1-IL-6 axis. We show that liraglutide transiently increases IL-6 in mouse circulation and IL-6R signaling in AT. Metronomic liraglutide treatment resulted in AT browning and thermogenesis linked with STAT3 activation. IL-6-blocking antibody treatment inhibited STAT3 activation in AT and suppressed liraglutide-induced increase in thermogenesis and glucose utilization. We show that adipose IL-6R knockout mice still display liraglutide-induced weight loss but lack thermogenic adipocyte browning and metabolism activation. We conclude that the anti-diabetic effects of GLP1 analogs are mediated by transient upregulation of IL-6, which activates canonical IL-6R signaling and thermogenesis