Archive for the ‘Lipids, Lipoproteins, and Cardiovascular Risk Factors’ Category
Comparison of Midregional Pro-A-Type Natriuretic Peptide and the N-Terminal Pro-B-Type Natriuretic Peptide for Predicting Mortality and Cardiovascular Events [Brief Communications]
Written by van Hateren, K. J. J., Alkhalaf, A., Kleefstra, N., Groenier, K. H., de Jong, P. E., de Zeeuw, D., Gans, R. O. B., Struck, J., Bilo, H. J. G., Gansevoort, R. T., Bakker, S. J. L. on December 28, 2011 – 10:37 pm -N-terminal pro–B-type natriuretic peptide (NT-proBNP) provides prognostic information on mortality and future cardiovascular events for individuals from the general population. A novel immunoassay was recently developed that measures a midregional fragment of pro–A-type natriuretic peptide (MR-proANP). We compared the capabilities of MR-proANP and NT-proBNP for predicting mortality and cardiovascular events in a population-based study.
METHODS:A total of 7819 patients participated in the population-based Prevention of Renal and Vascular End-stage Disease (PREVEND) study, a prospective observational study. Three clinical end points were studied: all-cause mortality, cardiovascular mortality, and cardiovascular events. After a median follow-up of 10.5 years, we used a Cox proportional hazards model to investigate the relationship between the 2 natriuretic peptides and the clinical end points. The Harrell C statistic and the integrated discrimination improvement (IDI) were used to compare MR-proANP and NT-proBNP.
RESULTS:Increased plasma concentrations of both natriuretic peptides were associated with an increased risk of all-cause mortality and cardiovascular events, after adjustment for age, sex, and other cardiovascular risk factors. According to the Harrell C statistic analysis, the models with MR-proANP and NT-proBNP were comparable in predicting all-cause mortality, cardiovascular mortality, and cardiovascular events. In contrast to NT-proBNP, MR-proANP was not independently related to cardiovascular mortality. In all models, the IDI was higher for NT-proBNP than for MR-proANP.
CONCLUSIONS:MR-proANP was as efficient as NT-proBNP in predicting all-cause mortality, cardiovascular mortality, and cardiovascular events; however, its association with cardiovascular mortality was not independent from other confounders.
Tags: chemistry, clinic
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Biomarkers for Predicting Serious Cardiac Outcomes at 72 Hours in Patients Presenting Early after Chest Pain Onset with Symptoms of Acute Coronary Syndromes [Brief Communications]
Written by Kavsak, P. A., Hill, S. A., Bhanich Supapol, W., Devereaux, P. J., Worster, A. on December 28, 2011 – 10:37 pm -Most outcome studies of patients presenting early to the emergency department with potential acute coronary syndromes have focused on either the index diagnosis of myocardial infarction (MI) or a composite end point at a later time frame (30 days or 1 year). We investigated the performance of 9 biomarkers for an early serious outcome.
METHODS:Patients (n = 186) who presented to the emergency department within 6 h of chest pain onset had their presentation serum sample measured for the following analytes: creatine kinase, creatine kinase isoenzyme MB, enhanced AccuTnI troponin I (Beckman Coulter), high-sensitivity cardiac troponin T (hs-cTnT), ischemia-modified albumin, interleukin-6, investigation use only hs-cTnI (Beckman Coulter), N-terminal pro–B-type natriuretic peptide, and cardiac troponin I (Abbott AxSym). We followed patients until 72 h after presentation and determined whether they experienced the following serious cardiac outcomes: MI, heart failure, serious arrhythmia, refractory ischemic cardiac pain, or death. ROC curves were analyzed to determine the area under the ROC curve (AUC) and optimal cutoffs for the biomarkers.
RESULTS:The AUCs for the hs-cTnI assay (0.86; 95% CI, 0.76–0.96), the AccuTnI assay (0.86; 95% CI, 0.78–0.95), and the hs-cTnT assay (0.82; 95% CI, 0.71–0.94) assays were significantly higher than those for the other 6 assays (AUC values ≤0.71 for the rest of the biomarkers, P < 0.05). The ROC curve–derived optimal cutoffs were ≥19 ng/L (diagnostic sensitivity, 80%; specificity, 88%), ≥0.018 μg/L (diagnostic sensitivity, 75%; specificity, 86%), and ≥32 ng/L (diagnostic sensitivity, 68%; specificity, 92%) for the hs-cTnI, AccuTnI, and hs-cTnT assays, respectively.
CONCLUSIONS:The optimal cutoffs for predicting serious cardiac outcomes in this low-risk population are different from the published 99th percentiles. Larger studies are required to verify these findings.
Tags: chemistry, clinic
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Growth Differentiation Factor 15: A Canary in a Coal Mine? [Editorials]
Written by Ho, J. E., Wang, T. J. on December 28, 2011 – 10:37 pm -Tags: chemistry, clinic
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Statins, Plasma Proprotein Convertase Subtilisin/Kexin Type 9 Concentrations, and LDL Lowering [Editorials]
Written by Khera, A. on December 28, 2011 – 10:37 pm -Tags: chemistry, clinic
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C-Reactive Protein Induces Release of Both Endothelial Microparticles and Circulating Endothelial Cells In Vitro and In Vivo: Further Evidence of Endothelial Dysfunction [Lipids, Lipoproteins, and Cardiovascular Risk Factors]
Written by Devaraj, S., Kumaresan, P. R., Jialal, I. on November 28, 2011 – 10:31 pm -Inflammation is pivotal in atherosclerosis. A key early event in atherosclerosis is endothelial dysfunction. C-reactive protein (CRP), the prototypic marker of inflammation in humans, is a risk marker for cardiovascular disease, and there is mounting evidence to support its role in atherothrombosis. CRP has been shown to promote endothelial dysfunction both in vitro and in vivo. Emerging biomarkers of endothelial dysfunction include circulating endothelial cells (CECs) and endothelial microparticles (EMPs). However, there is a paucity of data examining the effect of CRP on CEC and EMP production in vitro and in vivo.
METHODS:In this report, we treated human aortic endothelial cells (HAECs) with increasing concentrations of CRP (0–50 μg/mL) or boiled CRP. We counted CECs and EMPs by flow cytometry.
RESULTS:Although CRP treatment resulted in a significant increase in release of both CECs and EMPs, boiled CRP failed to have an effect. Pretreatment of HAECs with sepiapterin or diethylenetriamine NONOate, both of which preserve nitric oxide (NO), resulted in attenuation of CRP's effects on CECs and EMPs. CD32 and CD64 blocking antibodies but not CD16 antibody or lectin-like oxidized LDL receptor 1 small interfering RNA (LOX-1 siRNA) prevented CRP-induced production of CECs and EMPs. Furthermore, delivery of human CRP to Wistar rats compared with human serum albumin resulted in significantly increased CECs and EMPs, corroborating the in vitro findings.
CONCLUSIONS:We provide novel data that CRP, via NO deficiency, promotes endothelial dysfunction by inducing release of CECs and EMPs, which are biomarkers of endothelial dysfunction.
Tags: chemistry, clinic
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Risk Prediction with Serial Myeloperoxidase Monitoring in Patients with Acute Chest Pain [Lipids, Lipoproteins, and Cardiovascular Risk Factors]
Written by Nicholls, S. J., Wilson Tang, W. H., Brennan, D., Brennan, M.-L., Mann, S., Nissen, S. E., Hazen, S. L. on November 28, 2011 – 10:31 pm -Although myeloperoxidase (MPO) monitoring is predictive for cardiovascular outcomes in suspected acute coronary syndromes, the value of serial testing is unknown.
METHODS:We investigated the relationship between serial MPO concentrations in 490 individuals with acute chest pain and incident major adverse cardiac events (MACE) during 6 months of follow-up. We measured MPO with the CardioMPO assay, and cardiac troponin I (cTnI), with the Abbott Architect assay.
RESULTS:Plasma MPO concentrations during the first 16 h were higher in individuals who experienced MACE. Higher MPO quartiles predicted a greater likelihood of 6-month MACE at baseline [OR (95% CI), 2.4 (1.4–4.1), P = 0.001 for highest vs lowest quartile] and all subsequent time points, with strongest predictive ability found in 16-h postbaseline samples [9.9 (4.7–20.9), P < 0.001 for highest vs lowest quartile]. MPO was predictive for MACE among individuals whose cTnI remained within reference intervals (<0.028 μg/L). The lowest rate of missed cases was found when MPO was <640 pmol/L at baseline and all other time points. Serial MPO monitoring predicted MACE risk better than baseline MPO measurements alone (c statistic 0.813 vs 0.602; P = 0.002), including in individuals whose cTnI remained within reference intervals (c statistic 0.903; P = 0.009). Combined serial cTnI and MPO testing improved accuracy for predicting 6-month MACE, reduced the number of missed MACE events from cTnI testing alone, and improved risk classification in 26.1% of patients.
CONCLUSIONS:MPO concentrations are predictive of outcome up to 16 h after presentation with chest pain and predict events missed by cTnI testing, supporting a potential role in rapid patient triage.
Tags: chemistry, clinic
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Purified Anthocyanin Supplementation Improves Endothelial Function via NO-cGMP Activation in Hypercholesterolemic Individuals [Lipids, Lipoproteins, and Cardiovascular Risk Factors]
Written by Zhu, Y., Xia, M., Yang, Y., Liu, F., Li, Z., Hao, Y., Mi, M., Jin, T., Ling, W. on October 28, 2011 – 9:31 pm -Anthocyanins have been shown to improve endothelial function in animal models. However, whether these compounds have similar beneficial effects in humans is largely unknown.
METHODS:In a short-term crossover study, 12 hypercholesterolemic individuals were given oral anthocyanins (320 mg) isolated from berries or placebo. Brachial artery flow-mediated dilation (FMD) was assessed before and after the intervention. In a long-term intervention trial (12 weeks), 150 hypercholesterolemic individuals were given anthocyanins (320 mg/day, n = 75) or placebo (n = 75), after which we measured FMD, plasma cGMP, and other serum biomarkers. Another short-term intervention was conducted in the presence of NO-cGMP inhibitors in 6 people and in a rat aortic ring model (n = 8).
RESULTS:Significant increases of FMD from 8.3% (0.6%) at baseline to 11.0% (0.8%) at 1 h and 10.1% (0.9%) at 2 h were observed after short-term anthocyanin consumption, concomitantly with increases of plasma anthocyanin concentrations (P < 0.05). In the study participants who received long-term anthocyanin intervention, compared with the control group, we observed significant increases in the FMD (28.4% vs 2.2%), cGMP (12.6% vs –1.2%), and HDL-cholesterol concentrations, but decreases in the serum soluble vascular adhesion molecule-1 and LDL cholesterol concentrations (P < 0.05). The changes in the cGMP and HDL cholesterol concentrations positively correlated with FMD in the anthocyanin group (P < 0.05). In the presence of NO-cGMP inhibitors, the effects of anthocyanin on endothelial function were abolished in human participants and in a rat aortic ring model.
CONCLUSIONS:Anthocyanin supplementation improves endothelium-dependent vasodilation in hypercholesterolemic individuals. This effect involves activation of the NO-cGMP signaling pathway, improvements in the serum lipid profile, and decreased inflammation.
Tags: chemistry, clinic
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An About-Face for C-Reactive Protein? [Editorials]
Written by Szalai, A. J. on September 28, 2011 – 11:05 pm -Tags: chemistry, clinic
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Lectin-like Oxidized LDL Receptor 1 Is Involved in CRP-Mediated Complement Activation [Lipids, Lipoproteins, and Cardiovascular Risk Factors]
Written by Fujita, Y., Yamaguchi, S., Kakino, A., Iwamoto, S., Yoshimoto, R., Sawamura, T. on September 28, 2011 – 11:05 pm -C-reactive protein (CRP) is purported to be a risk factor that acts independently of LDL cholesterol in predicting all-cause mortality in patients with ischemic heart disease. Lectin-like oxidized LDL receptor 1 (LOX-1) impairs endothelial function and exacerbates myocardial injury. We recently demonstrated that CRP increased vascular permeability through direct binding to LOX-1. Here we examined, using a hypertensive rat model, whether LOX-1 is involved in CRP-induced complement activation.
METHODS AND RESULTS:In the cultured LOX-1–expressing cell line hLOX-1-CHO, CRP increased complement activation, but did not do so in native CHO cells. Depleting C1q from serum abolished CRP-induced complement activation. Incubation of CRP with serum on immobilized recombinant LOX-1 similarly showed that CRP activated C1q-requiring classical complement pathway in a LOX-1–dependent manner. Interestingly, the interaction between CRP and LOX-1 was dependent on Ca2+ ion and competed with phosphocholine, suggesting that LOX-1 bound to the B-face of CRP with a phosphocholine-binding domain. This was in contrast to Fc receptors, to which CRP bound in A-face with complement-binding domain. In vivo, intradermal injection of CRP to hypertensive SHRSP rats induced complement activation detected by C3d deposition and leukocyte infiltration around the injected area. Anti–LOX-1 antibody reduced the extent of complement activation and leukocyte infiltration.
CONCLUSIONS:LOX-1 appears to be involved in CRP-induced complement activation, and thus may serve to locate the site of CRP-induced complement activation and inflammation.
Tags: chemistry, clinic
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Heritability, Weak Effects, and Rare Variants in Genomewide Association Studies [Opinion]
Written by Cambien, F. on August 26, 2011 – 9:31 pm -Tags: chemistry, clinic
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Incremental Value of High-Sensitivity Cardiac Troponin T for Risk Prediction in Patients with Suspected Acute Myocardial Infarction [Proteomics and Protein Markers]
Written by Hochholzer, W., Reichlin, T., Twerenbold, R., Stelzig, C., Hochholzer, K., Meissner, J., Haaf, P., Schaub, N., Steuer, S., Bassetti, S., Reiter, M., Roost, K., Freidank, H., Winkler, K., Mueller, C. on August 26, 2011 – 9:31 pm -High-sensitivity cardiac troponin assays have better analytical precision and sensitivity than earlier-generation assays when measuring cardiac troponin at low concentrations. We evaluated whether use of a high-sensitivity assay could further improve risk stratification compared with a standard cardiac troponin assay.
METHODS:We enrolled consecutive patients presenting with acute chest pain, 30% of whom were diagnosed with acute coronary syndrome. Blood samples were drawn at the time of presentation. We measured cardiac troponin T with a standard fourth-generation assay (cTnT) and a high-sensitivity assay (hs-cTnT) (both Roche Diagnostics) and followed the patients for 24 months.
RESULTS:Of the 1159 patients, 76 died and 42 developed an acute myocardial infarction (AMI). Prognostic accuracy of hs-cTnT for death was significantly higher [area under ROC curve (AUC) 0.79, 95% CI 0.74–0.84] than that of cTnT (AUC 0.69, 95% CI 0.62–0.76; P < 0.001). After adjustment for Thrombolysis in Myocardial Infarction (TIMI) risk score (that included the cTnT assay result), hs-cTnT above the 99th percentile (0.014 µg/L) was associated with a hazard ratio for death of 2.60 (95% CI 1.42–4.74). Addition of hs-cTnT to the risk score improved the reclassification of patients (net reclassification improvement 0.91; 95% CI 0.67–1.14; P < 0.001). Subgroup analyses showed that this effect resulted from the better classification of patients without AMI at time of testing. hs-cTnT outperformed cTnT in the prediction of AMI during follow-up (P=0.02), but was not independently predictive for this endpoint.
CONCLUSIONS:Concentrations of hs-cTnT >0.014 µg/L improve the prediction of death but not subsequent AMI in unselected patients presenting with acute chest pain.
Tags: chemistry, clinic
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Using Nonfasting Lipids–Hemodilution or Convenience? [Letters to the Editor]
Written by Lund, S. S., Jensen, T. on August 26, 2011 – 9:31 pm -Tags: chemistry, clinic
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In Reply [Letters to the Editor]
Written by Langsted, A., Nordestgaard, B. G. on August 26, 2011 – 9:31 pm -Tags: chemistry, clinic
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Beat Biomarkers: Expansion and Challenges for Diagnosis, Prognosis, Differentiation, and Treatment [Review] <<>>
Written by Saenger, A. K., Christenson, R. H. on January 1, 1970 – 1:00 am -Background: Example is a acid mould encompassing a extensive stretch of pathophysiological entities that cover thrombosis, hemorrhage, and embolism. Aware diagnosis of pulsation relies on physician clinical inquiry and is to boot supplemented with individual neuroimaging techniques. A put set or multiple sets of blood biomarkers that could be habituated to in an stabbing environment to diagnosis stroke, oppose internuncio touch types, or neck foresee an initial/reoccurring whack would be uncommonly valuable.
Content: We chat about the ongoing classification, diagnosis, and treatment of stroke, focusing on use of novella biomarkers (either separate markers or multiple markers within a panel) that be experiencing been calculated in a heterogeneity of clinical settings.
Summary: The common diagnosis of flourish remains hampered and delayed due to be deficient in of a fit physicalism for precipitate (ideally point-of-care), accurate, and analytically delicate biomarker-based testing. There is a free basic for additional enlargement and translational digging in this range. Quiescent biomarkers identified penury to be transitioned post-haste into clinical validation testing for forwards opinion in an discriminating tittle setting; to do so would consequences and uplift sedulous outcomes and distinction of sprightliness.
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Dispersal of Asymmetric Dimethylarginine expanse 980 Healthy, Older Adults of Dissimilar Ethnicities [Lipids, Lipoproteins, and Cardiovascular Chance Factors] <<>>
Written by Sydow, K., Fortmann, S. P., Fair, J. M., Varady, A., Hlatky, M. A., Go, A. S., Iribarren, C., Tsao, P. S., for the ADVANCE Investigators on January 1, 1970 – 1:00 am -Background: Endothelium-derived nitric oxide plays a pivotal duty in the ordinance of vascular tone colour and the situation of cardiovascular ailment. The endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA) has emerged as a narrative cardiovascular gamble financier. ADMA appears to be an beyond predictor for cardiovascular and whole mortality. However, the maturity of studies investigating the clinical situation of ADMA were performed in European survey populations with few individuals of other ethnicities.
Methods: We performed a cross-sectional learn about of 980 healthy, older (age 60–72 years) individuals of various ethnicities living in the San Francisco Bay stretch and analyzed ADMA plasma concentrations and their relationship to other cardiovascular chance factors. Plasma ADMA concentrations were premeditated using a recently developed, powerfully subtle ELISA.
Results: In our inviolate sample, we were clever to interpret a recommendation break for ADMA plasma concentrations of 0.47 (90% CI 0.46–0.48) µmol/L to 0.85 (0.84–0.89) µmol/L. The using ADMA concentration was 0.63 (SD 0.11) µmol/L (median 0.61 µmol/L). Middling ADMA concentrations were significantly reduce in African Americans (0.60 µmol/L; P < 0.01) and interbred non-Hispanics (0.60 µmol/L; P < 0.05) compared with whites (0.63 µmol/L). ADMA was emphatically correlated with cystatin-C in both men ( = 0.29) and women ( = 0.37), and median plasma ADMA concentrations increased across cystatin-C quintiles.
Conclusions: ADMA varies about 2-fold across a trim test of older men and women, correlates with age, main part gather index, and renal function, and is extraordinary across ethnic groups. Additional studies in a wider age kitchen range and including larger ethnic subgroups would be helpful.
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