Differential procoagulatory response of microvascular, arterial and venous endothelial cells upon inflammation in vitro.

INTRODUCTION: Inflammation induces a procoagulant phenotype of endothelial cells (EC) with the exposure of tissue factor (TF), a potent initiator of the extrinsic coagulation cascade. Although systemic inflammation affects the whole vascular system, thrombotic lesions occur particularly in microcirculation. This raises the question of whether TF-procoagulant activity (TF-PCA) differs between EC from arterial, venous, and microvascular beds. MATERIALS AND METHODS: Functional coagulation tests, including TF-PCA, and inflammatory responses were investigated on arterial, venous and microvascular endothelial cells. Interleukin-6 (IL-6) and TF-levels were determined in cohort of 59 septic patients. RESULTS: We found that tumor necrosis factor alpha (TNFα), lipopolysaccharide, and interleukin-1ß induce a solid, dose-dependent increase in TF-PCA, which is highest in microvascular EC. A positive correlation of interleukin-6 (IL-6) with TF levels was observed in a cohort of 59 septic patients. In contrast, TF-PCA was independent of IL-6 concentrations in vitro. Re-analysis of publicly available gene expression data revealed that among the top 50 genes annotated to coagulation, TF is one of three regulated genes common to the three investigated EC subtypes. The response to inflammatory stimuli in terms of exposure of leukocyte-endothelial- and platelet-endothelial adhesion molecules (E-selectin and PECAM-1), remodeling of adherens junctions, co-exposure of negatively charged surfaces nor breakdown of the glycocalyx was comparable between the EC subtypes and did not explain the higher TF-PCA on microvascular cells. We found that the ratio of TF and TFPI exposure on the endothelial membrane significantly differs between the EC subtypes. CONCLUSIONS: These findings indicate that the ratio of TF to its inhibitor TFPI is a determinant of endothelial TF-PCA, which is most pronounced on microvascular endothelial cells and might explain why the microvascular system is particularly susceptible to inflammation-induced thrombosis.

Biomarkers for prediction of renal replacement therapy in acute kidney injury: a systematic review and meta-analysis.

PURPOSE: Acute kidney injury (AKI) frequently occurs in critically ill patients and often precipitates use of renal replacement therapy (RRT). However, the ideal circumstances for whether and when to start RRT remain unclear. We performed evidence synthesis of the available literature to evaluate the value of biomarkers to predict receipt of RRT for AKI. METHODS: We conducted a PRISMA-guided systematic review and meta-analysis including all trials evaluating biomarker performance for prediction of RRT in AKI. A systematic search was applied in MEDLINE, Embase, and CENTRAL databases from inception to September 2017. All studies reporting an area under the curve (AUC) for a biomarker to predict initiation of RRT were included. RESULTS: Sixty-three studies comprising 15,928 critically ill patients (median per study 122.5 [31-1439]) met eligibility. Forty-one studies evaluating 13 different biomarkers were included. Of these biomarkers, neutrophil gelatinase-associated lipocalin (NGAL) had the largest body of evidence. The pooled AUCs for urine and blood NGAL were 0.720 (95% CI 0.638-0.803) and 0.755 (0.706-0.803), respectively. Blood creatinine and cystatin C had pooled AUCs of 0.764 (0.732-0.796) and 0.768 (0.729-0.807), respectively. For urine biomarkers, interleukin-18, cystatin C, and the product of tissue inhibitor of metalloproteinase-2 and insulin growth factor binding protein-7 showed pooled AUCs of 0.668 (0.606-0.729), 0.722 (0.575-0.868), and 0.857 (0.789-0.925), respectively. CONCLUSION: Though several biomarkers showed promise and reasonable prediction of RRT use for critically ill patients with AKI, the strength of evidence currently precludes their routine use to guide decision-making on when to initiate RRT.

Risk prediction in Barrett's esophagus - aspects of a combination of molecular and epidemiologic biomarkers reflecting alterations of the microenvironment.

Barrett's esophagus (BE) is a chronic, metaplastic lesion of the esophagus and the only known precursor of esophageal adenocarcinoma. The identification of risk factors to assess the risk for BE and their correspondence with hallmarks of malignant progression for early stratification purposes is critically needed. Data legitimate the assumption that aside of reflux symptoms and related conditions, also demographic and environmental factors are thought to be associated with the risk for BE and its progression to esophageal adenocarcinoma. Molecular biomarkers and inflammatory mechanisms are subjects of intensive research and dispone of promising features regarding risk assessment especially for progressive BE. The amount of investigated epidemiologic factors, as well as discovered biomarkers gets confusingly large. Despite the recognized potential relevance of environmental and molecular factors, the efforts to date have resulted in moderately applicable risk estimates. More prospective data is needed to allow an imputation of the mostly retrospectively assessed factors to reappraise their meaningfulness in risk prediction approaches.