22 research outputs found
Constraints on ultra-high energy neutrinos from optically thick astrophysical accelerators
The Z-burst mechanism invoked to explain ultra-high energy cosmic rays is
severely constrained by measurements of the cosmic gamma-ray background by
EGRET. We discuss the case of optically thick sources and show that jets and
hot spots of active galaxies cannot provide the optical depth required to
suppress the photon flux. Other extragalactic accelerators (AGN cores and sites
of gamma ray bursts), if they are optically thick, could be tested by future
measurements of the secondary neutrino flux.Comment: 9 pages, 1 figure; v2: 10 pages, references added; experimental data
on neutrino fluxes updated significantly; to be published in Astropart.Phy
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
Two-Dimensional and zero-Dimensional Structures of Semimagnetic Semiconductors Prepared by Pulsed Laser Deposition
Synthesis and Characterization of Semimagnetic Semiconductor Nanocrystals for Spin Electronics
Supplementary Material for: Genomic and Metabolic Responses to Methionine-Restricted and Methionine-Restricted, Cysteine-Supplemented Diets in Fischer 344 Rat Inguinal Adipose Tissue, Liver and Quadriceps Muscle
<b><i>Background/Aims:</i></b> Methionine restriction (MR) is a dietary intervention that increases lifespan, reduces adiposity and improves insulin sensitivity. These effects are reversed by supplementation of the MR diet with cysteine (MRC). Genomic and metabolomic studies were conducted to identify potential mechanisms by which MR induces favorable metabolic effects, and that are reversed by cysteine supplementation. <b><i>Methods:</i></b> Gene expression was examined by microarray analysis and TaqMan quantitative PCR. Levels of selected proteins were measured by Western blot and metabolic intermediates were analyzed by mass spectrometry. <b><i>Results:</i></b> MR increased lipid metabolism in inguinal adipose tissue and quadriceps muscle while it decreased lipid synthesis in liver. In inguinal adipose tissue, MR not only caused the transcriptional upregulation of genes associated with fatty acid synthesis but also of <i>Lpin1</i>, <i>Pc</i>, <i>Pck1</i> and <i>Pdk1</i>, genes that are associated with glyceroneogenesis. MR also upregulated lipolysis-associated genes in inguinal fat and led to increased oxidation in this tissue, as suggested by higher levels of methionine sulfoxide and 13-HODE + 9-HODE compared to control-fed (CF) rats. Moreover, MR caused a trend toward the downregulation of inflammation-associated genes in inguinal adipose tissue. MRC reversed most gene and metabolite changes induced by MR in inguinal adipose tissue, but drove the expression of <i>Elovl6</i>, <i>Lpin1</i>, <i>Pc</i>, and <i>Pdk1</i> below CF levels. In liver, MR decreased levels of a number of long-chain fatty acids, glycerol and glycerol-3-phosphate corresponding with the gene expression data. Although MR increased the expression of genes associated with carbohydrate metabolism, levels of glycolytic intermediates were below CF levels. MR, however, stimulated gluconeogenesis and ketogenesis in liver tissue. As previously reported, sulfur amino acids derived from methionine were decreased in liver by MR, but homocysteine levels were elevated. Increased liver homocysteine levels by MR were associated with decreased cystathionine β-synthase (CBS) protein levels and lowered vitamin B6 and 5-methyltetrahydrofolate (5MeTHF) content. Finally, MR upregulated fibroblast growth factor 21 (FGF21) gene and protein levels in both liver and adipose tissues. MRC reversed some of MR’s effects in liver and upregulated the transcription of genes associated with inflammation and carcinogenesis such as <i>Cxcl16</i>, <i>Cdh17</i>, <i>Mmp12</i>, <i>Mybl1</i>, and <i>Cav1</i> among others. In quadriceps muscle, MR upregulated lipid metabolism-associated genes and increased 3-hydroxybutyrate levels suggesting increased fatty acid oxidation as well as stimulation of gluconeogenesis and glycogenolysis in this tissue. <b><i>Conclusion:</i></b> Increased lipid metabolism in inguinal adipose tissue and quadriceps muscle, decreased triglyceride synthesis in liver and the downregulation of inflammation-associated genes are among the factors that could favor the lean phenotype and increased insulin sensitivity observed in MR rats
Global Differences in Characteristics, Precipitants, and Initial Management of Patients Presenting with Acute Heart Failure
Importance: Acute heart failure (AHF) precipitates millions of hospital admissions worldwide, but previous registries have been country or region specific. Objective: To conduct a prospective contemporaneous comparison of AHF presentations, etiologic factors and precipitants, treatments, and in-hospital outcomes among global regions through the International Registry to Assess Medical Practice with Longitudinal Observation for Treatment of Heart Failure (REPORT-HF). Design, Setting, and Participants: A total of 18553 adults were enrolled during a hospitalization for AHF. Patients were recruited from the acute setting in Western Europe (WE), Eastern Europe (EE), Eastern Mediterranean and Africa (EMA), Southeast Asia (SEA), Western Pacific (WP), North America (NA), and Central and South America (CSA). Patients with AHF were approached for consent and excluded only if there was recent participation in a clinical trial. Patients were enrolled from July 23, 2014, to March 24, 2017. Statistical analysis was conducted from April 18 to June 29, 2018; revised analyses occurred between August 6 and 29, 2019. Main Outcomes and Measures: Heart failure etiologic factors and precipitants, treatments, and in-hospital outcomes among global regions. Results: A total of 18553 patients were enrolled at 358 sites in 44 countries. The median age was 67.0 years (interquartile range [IQR], 57-77), 11372 were men (61.3%), 9656 were white (52.0%), 5738 were Asian (30.9%), and 867 were black (4.7%). A history of HF was present in more than 50% of the patients and 40% were known to have a prior left-ventricular ejection fraction lower than 40%. Ischemia was a common AHF precipitant in SEA (596 of 2329 [25.6%]), WP (572 of 3354 [17.1%]), and EMA (364 of 2241 [16.2%]), whereas nonadherence to diet and medications was most common in NA (306 of 1592 [19.2%]). Median time to the first intravenous therapy was 3.0 (IQR, 1.4-5.6) hours in NA; no other region had a median time above 1.2 hours (P <.001). This treatment delay remained after adjusting for severity of illness (P <.001). Intravenous loop diuretics were the most common medication administered in the first 6 hours of AHF management across all regions (65.4%-89.9%). Despite similar initial blood pressure across all regions, inotropic agents were used approximately 3 times more often in SEA, WP, and EE (11.3%-13.5%) compared with NA and WE (3.1%-4.3%) (P <.001). Older age (odds ratio [OR], 1.0; 95% CI, 1.00-1.02), HF etiology (ischemia: OR, 1.65; 95% CI, 1.11-2.44; valvular: OR, 2.10; 95% CI, 1.36-3.25), creatinine level greater than 2.75 mg/dL (OR, 1.85; 95% CI, 0.71-2.40), and chest radiograph signs of congestion (OR, 2.03; 95% CI, 1.39-2.97) were all associated with increased in-hospital mortality. Similarly, younger age (OR, -0.04; 95% CI, -0.05 to -0.02), HF etiology (ischemia: OR, 0.77; 95% CI, 0.26-1.29; valvular: OR, 2.01; 95% CI, 1.38-2.65), creatinine level greater than 2.75 mg/dL (OR, 1.16; 95% CI, 0.31-2.00), and chest radiograph signs of congestion (OR, 1.02; 95% CI, 0.57-1.47) were all associated with increased in-hospital LOS. Conclusions and Relevance: Data from REPORT-HF suggest that patients are similar across regions in many respects, but important differences in timing and type of treatment exist, identifying region-specific gaps in medical management that may be associated with patient outcomes. © 2020 American Medical Association. All rights reserved
Post-discharge prognosis of patients admitted to hospital for heart failure by world region, and national level of income and income disparity (REPORT-HF): a cohort study
Background: Heart failure is a global public health problem, affecting a large number of individuals from low-income and middle-income countries. REPORT-HF is, to our knowledge, the first prospective global registry collecting information on patient characteristics, management, and prognosis of acute heart failure using a single protocol. The aim of this study was to investigate differences in 1-year post-discharge mortality according to region, country income, and income inequality. Methods: Patients were enrolled during hospitalisation for acute heart failure from 358 centres in 44 countries on six continents. We stratified countries according to a modified WHO regional classification (Latin America, North America, western Europe, eastern Europe, eastern Mediterranean and Africa, southeast Asia, and western Pacific), country income (low, middle, high) and income inequality (according to tertiles of Gini index). Risk factors were identified on the basis of expert opinion and knowledge of the literature. Findings: Of 18 102 patients discharged, 3461 (20%) died within 1 year. Important predictors of 1-year mortality were old age, anaemia, chronic kidney disease, presence of valvular heart disease, left ventricular ejection fraction phenotype (heart failure with reduced ejection fraction [HFrEF] vs preserved ejection fraction [HFpEF]), and being on guideline-directed medical treatment (GDMT) at discharge (p&lt;0·0001 for all). Patients from eastern Europe had the lowest 1-year mortality (16%) and patients from eastern Mediterranean and Africa (22%) and Latin America (22%) the highest. Patients from lower-income countries (ie, ≤US12 235 per capita) or lower income inequality (ie, from the lowest Gini tertile). Compared with patients with HFrEF, patients with HFpEF had a lower 1-year mortality with little variation by income level (pinteraction for HFrEF vs HFpEF &lt;0·0001). Interpretation: Acute heart failure is associated with a high post-discharge mortality, particularly in patients with HFrEF from low-income regions with high income inequality. Regional differences exist in the proportion of eligible patients discharged on GDMT, which was strongly associated with mortality and might reflect lack of access to post-discharge care and prescribing of GDMT. Funding: Novartis Pharma. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license