Plasma lipidome and risk of atrial fibrillation: results from the PREDIMED trial

The potential role of the lipidome in atrial fibrillation (AF) development is still widely unknown. We aimed to assess the association between lipidome profiles of the Prevención con Dieta Mediterránea (PREDIMED) trial participants and incidence of AF. We conducted a nested case-control study (512 incident centrally adjudicated AF cases and 735 controls matched by age, sex, and center). Baseline plasma lipids were profiled using a Nexera X2 U-HPLC system coupled to an Exactive Plus orbitrap mass spectrometer. We estimated the association between 216 individual lipids and AF using multivariable conditional logistic regression and adjusted the p values for multiple testing. We also examined the joint association of lipid clusters with AF incidence. Hitherto, we estimated the lipidomics network, used machine learning to select important network-clusters and AF-predictive lipid patterns, and summarized the joint association of these lipid patterns weighted scores. Finally, we addressed the possible interaction by the randomized dietary intervention.Forty-one individual lipids were associated with AF at the nominal level (p < 0.05), but no longer after adjustment for multiple-testing. However, the network-based score identified with a robust data-driven lipid network showed a multivariable-adjusted ORper+1SD of 1.32 (95% confidence interval: 1.16-1.51; p < 0.001). The score included PC plasmalogens and PE plasmalogens, palmitoyl-EA, cholesterol, CE 16:0, PC 36:4;O, and TG 53:3. No interaction with the dietary intervention was found. A multilipid score, primarily made up of plasmalogens, was associated with an increased risk of AF. Future studies are needed to get further insights into the lipidome role on AF.Current Controlled Trials number, ISRCTN35739639

Autoantibodies against type I IFNs in patients with critical influenza pneumonia

In an international cohort of 279 patients with hypoxemic influenza pneumonia, we identified 13 patients (4.6%) with autoantibodies neutralizing IFN-alpha and/or -omega, which were previously reported to underlie 15% cases of life-threatening COVID-19 pneumonia and one third of severe adverse reactions to live-attenuated yellow fever vaccine. Autoantibodies neutralizing type I interferons (IFNs) can underlie critical COVID-19 pneumonia and yellow fever vaccine disease. We report here on 13 patients harboring autoantibodies neutralizing IFN-alpha 2 alone (five patients) or with IFN-omega (eight patients) from a cohort of 279 patients (4.7%) aged 6-73 yr with critical influenza pneumonia. Nine and four patients had antibodies neutralizing high and low concentrations, respectively, of IFN-alpha 2, and six and two patients had antibodies neutralizing high and low concentrations, respectively, of IFN-omega. The patients' autoantibodies increased influenza A virus replication in both A549 cells and reconstituted human airway epithelia. The prevalence of these antibodies was significantly higher than that in the general population for patients 70 yr of age (3.1 vs. 4.4%, P = 0.68). The risk of critical influenza was highest in patients with antibodies neutralizing high concentrations of both IFN-alpha 2 and IFN-omega (OR = 11.7, P = 1.3 x 10(-5)), especially those <70 yr old (OR = 139.9, P = 3.1 x 10(-10)). We also identified 10 patients in additional influenza patient cohorts. Autoantibodies neutralizing type I IFNs account for similar to 5% of cases of life-threatening influenza pneumonia in patients <70 yr old

Impact of ultra-low temperature long-term storage on the preanalytical variability of twentyone common biochemical analytes

Objectives: Retrospective studies frequently assume analytes long-term stability at ultra-low temperatures. However, these storage conditions, common among biobanks and research, may increase the preanalytical variability, adding a potential uncertainty to the measurements. This study is aimed to evaluate long-term storage stability of different analytes at <−70 °C and to assess its impact on the reference change value formula. Methods: Twenty-one analytes commonly measured in clinical laboratories were quantified in 60 serum samples. Samples were immediately aliquoted and frozen at <−70 °C, and reanalyzed after 11 ± 3.9 years of storage. A change in concentration after storage was considered relevant if the percent deviation from the baseline measurement was significant and higher than the analytical performance specifications. Results: Preanalytical variability (CVP) due to storage, determined by the percentage deviation, showed a noticeable dispersion. Changes were relevant for alanine aminotransferase, creatinine, glucose, magnesium, potassium, sodium, total bilirubin and urate. No significant differences were found in aspartate aminotransferase, calcium, carcinoembryonic antigen, cholesterol, C-reactive protein, direct bilirubin, free thryroxine, gammaglutamyltransferase, lactate dehydrogenase, prostatespecific antigen, triglycerides, thyrotropin, and urea. As nonnegligible, CVP must remain included in reference change value formula, which was modified to consider whether one or two samples were frozen. Conclusions: After long-term storage at ultra-low temperatures, there was a significant variation in some analytes that should be considered. We propose that reference change value formula should include the CVP when analyzing samples stored in these conditions

Immunosuppression routed via the kynurenine pathway: a biochemical and pathophysiologic approach

In the past years, it has been shown that kynurenines pathway is a regulator of both the innate and the adaptive immune responses. Particularly, the initial enzyme of this pathway, indoleamine 2,3-dioxygenase (IDO), is implicated in maintaining tolerance during pregnancy, and also can be expressed in tumors to avoid the immune attack. In this chapter, we will describe how the kynurenine pathway affects the immune system with important implications both in physiology and in pathology. The incorrect activation or blockade suppressive properties of the kynurenine pathway are also implicated in a number of other diseases such as AIDS or autoimmune diseases

Immunosuppression routed via the kynurenine pathway: a biochemical and pathophysiologic approach

In the past years, it has been shown that kynurenines pathway is a regulator of both the innate and the adaptive immune responses. Particularly, the initial enzyme of this pathway, indoleamine 2,3-dioxygenase (IDO), is implicated in maintaining tolerance during pregnancy, and also can be expressed in tumors to avoid the immune attack. In this chapter, we will describe how the kynurenine pathway affects the immune system with important implications both in physiology and in pathology. The incorrect activation or blockade suppressive properties of the kynurenine pathway are also implicated in a number of other diseases such as AIDS or autoimmune diseases

Comparison of six commercial serum exosome isolation methods suitable for clinical laboratories. Effect in cytokine analysis

Background: Exosomes are nanovesicles released by cells that can be detected in blood. Exosomes contain several molecules, such as cytokines that have potential utility as disease biomarkers. The aim of the present work is to compare six different commercial kits suitable for the clinical laboratory in relation to the efficiency and purity of exosome isolation, and their effect in subsequent cytokines analysis. Methods: Serum exosomes were obtained from 10 volunteers using six commercial kits: exoEasy, ExoQuick, Exo-spin, ME kit, ExoQuick Plus and Exo-Flow. Exosome concentrations and size distributions were quantified by nanoparticle tracking analysis. Exosome markers CD63, CD9 and TSG101 were determined by Western blot. ApoB and albumin were measured using nephelometry. S100A9, CXCL5 and CXCL12 were measured using a Luminex assay. Results: The concentration of particles obtained between different kits varied by a factor of 100. There was no correlation in particle concentrations extracted between different kits, except between ExoQuick and Exo-Flow. The highest exosome purity was achieved with ExoQuick Plus and exoEasy, while the lowest were achieved with ME and ExoQuick. Albumin was present in all exosome extracts analyzed and ApoB in all except those extracted with Exo-Flow and ME. Cytokine detection varied depending on the purification kit used and there was no correlation in cytokine concentrations between samples obtained with different kits. Conclusions: Both the sample and the type of commercial kit used affect the efficiency and purity of exosome isolation. In addition, the exosome purification method deeply affects the capability to detect and quantify cytokines

Effectiveness of a decision aid for promoting colorectal cancer screening in Spain: a randomized trial

Abstract Background Colorectal cancer (CRC) screening has shown to reduce incidence and mortality rates, and therefore is widely recommended for people above 50 years-old. However, despite the implementation of population-based screening programs in several countries, uptake rates are still low. Decision aids (DAs) may help patients to make informed decisions about CRC screening. Methods We performed a randomized controlled trial to assess the effectiveness of a DA developed to promote CRC screening, with patients from two primary care centers in Spain who never had underwent CRC screening. Contrary to center B (n = 24), Center A (n = 83) attended patients from an area where the population-based screening program was not implemented at that moment. Outcome measures were decisional conflict, knowledge of the disease and available screening options, intention to uptake the test, and concordance between patients’ goals/concerns and intention. Results In center A, there were significant differences favoring the DA in decisional conflict (p < 0.001) and knowledge (p < 0.001). The absolute differences favoring DA group in intention to undergo fecal occult blood test (10.5%) and colonoscopy (13.7%) were significant only before correction for attenuation. In center B the differences were significant only for knowledge (p < 0.001). Patients’ goals and concerns regarding the screening did not significantly predict their intention, and therefore we could not calculate a measure of concordance between the two constructs. Conclusions A DA improved the decisional process of participants who had never been invited to participate in the Spanish public CRC screening program, replicating previous results in this field. Future research is needed to identify subgroups that could benefit more from these interventions. Trial registration International Standard Registered Clinical/social Study Number: ISRCTN98108615 (Retrospectively registered on 27 December 2018)

Effectiveness of a decision aid for promoting colorectal cancer screening in Spain: a randomized trial

BACKGROUND: Colorectal cancer (CRC) screening has shown to reduce incidence and mortality rates, and therefore is widely recommended for people above 50 years-old. However, despite the implementation of population-based screening programs in several countries, uptake rates are still low. Decision aids (DAs) may help patients to make informed decisions about CRC screening. METHODS: We performed a randomized controlled trial to assess the effectiveness of a DA developed to promote CRC screening, with patients from two primary care centers in Spain who never had underwent CRC screening. Contrary to center B (n = 24), Center A (n = 83) attended patients from an area where the population-based screening program was not implemented at that moment. Outcome measures were decisional conflict, knowledge of the disease and available screening options, intention to uptake the test, and concordance between patients' goals/concerns and intention. RESULTS: In center A, there were significant differences favoring the DA in decisional conflict (p < 0.001) and knowledge (p < 0.001). The absolute differences favoring DA group in intention to undergo fecal occult blood test (10.5%) and colonoscopy (13.7%) were significant only before correction for attenuation. In center B the differences were significant only for knowledge (p < 0.001). Patients' goals and concerns regarding the screening did not significantly predict their intention, and therefore we could not calculate a measure of concordance between the two constructs. CONCLUSIONS: A DA improved the decisional process of participants who had never been invited to participate in the Spanish public CRC screening program, replicating previous results in this field. Future research is needed to identify subgroups that could benefit more from these interventions