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CKD is an independent risk factor for cardiovascular disease (CVD). The accumulation of uremic toxins in CKD induces oxidative stress and endothelial dysfunction. MicroRNA-92a (miR-92a) is induced by oxidative stress in endothelial cells (ECs) and involved in angiogenesis and atherosclerosis. We investigated a role for oxidative stress-responsive miR-92a in CKD. Our study of patients at three clinical sites showed increased serum miR-92a level with decreased kidney function. In cultured ECs, human CKD serum or uremic toxins (such as indoxyl sulfate), compared with non-CKD serum, induced the levels of miR-92a and suppressed the expression of miR-92a targets, including key endothelial-protective molecules. The antioxidant -acetylcysteine inhibited these vasculopathic properties. In rats, adenine-induced CKD associated with increased levels of miR-92a in aortas, serum, and CD144 endothelial microparticles. Furthermore, CD144 microparticles from human uremic serum contained more miR-92a than those from control serum. Additional analysis showed a positive correlation between serum levels of miR-92a and indoxyl sulfate in a cohort of patients with ESRD undergoing hemodialysis. Collectively, our findings suggest that the uremic toxins accumulated in CKD can upregulate miR-92a in ECs, which impairs EC function and predisposes patients to CVD.

Toll-like receptor-mediated NF-κB activation is a major innate immune reaction of vascular endothelial cells (ECs) in response to prooxidative and proinflammatory stimuli. We identified that TNF-α receptor-associated factor-interacting protein with a forkhead-associated domain (TIFA) is a regulator of priming (signal 1) and activating (signal 2) signals of nucleotide oligomerization domain-like receptor family pyrin domain-containing protein 3 (NLRP3) inflammasome in ECs. Oxidative and inflammatory stresses such as atheroprone flow and hyperlipidemia induce and activate TIFA in vitro and in vivo. For the priming of signal 1, sterol regulatory element-binding protein 2 transactivates TIFA, which in turn induces NF-κB activation and augments the transcription of NLRP3 inflammasome components. For the activation of signal 2, Akt is involved in TIFA Thr9 phosphorylation, which is essential for TIFA-TIFA homophilic oligomerization. Thr9 phosphorylation-dependent TIFA oligomerization facilitates the higher-order assembly of NLRP3 inflammasome, as indicated by the interaction between TIFA and caspase-1 in the activated ECs. Our results suggest that TIFA is a crucial mediator in the endothelial innate immune response by potentiating and amplifying NLRP3 inflammasome via augmenting signals 1 and 2.endothelial cells | inflammasome | innate immunity | NLRP3 | TIFA

Proprotein convertase subtilisin/kexin type 9 (PCSK9) affects cholesterol homeostasis by targeting hepatic low-density lipoprotein receptor (LDLR) for lysosomal degradation. Clinically, PCSK9 inhibitors effectively reduce LDL cholesterol (LDL-C) level and the incidence of cardiovascular events. Because microRNAs (miRs) are integral regulators of cholesterol homeostasis, we investigated the involvement of miR-483 in regulating LDL-C metabolism. Using in silico analysis, we predicted that miR-483-5p targets the 3'UTR of PCSK9 mRNA. In HepG2 cells, miR-483-5p targeted the PCSK9 3'UTR, leading to decreased PCSK9 protein and mRNA expression, increased LDLR expression and enhanced LDL-C uptake. In hyperlipidemic mice and humans, serum levels of total cholesterol and LDL-C were inversely correlated with miR-483-5p level. In mice, hepatic miR-483 overexpression increased LDLR level by targeting Pcsk9, with a significant reduction in plasma total cholesterol and LDL-C levels. Mechanistically, the cholesterol-lowering effect of miR-483-5p was significant in mice receiving AAV8 PCSK9-3'UTR but not Ldlrknockout mice or mice receiving AAV8 PCSK9-3'UTR (BS) with the miR-483-5p targeting site deleted. Thus, exogenously administered miR-483 or similarly optimized compounds have potential to ameliorate hypercholesterolemia.

Plasma-containing products are given during the pre-anhepatic stage of liver transplant surgery to correct abnormal thromboelastogram (TEG) values and prevent blood loss due to coagulation defects. However, evidence suggests that abnormal TEG results do not always predict bleeding. We questioned what effect using higher TEG values to initiate treatment would have on blood loss. A single transfusion protocol was used for all patients who underwent liver transplantation between 2007 and 2010. Thirty-eight patients received coagulation products when standard TEG cutoff values were exceeded, whereas another 39 patients received coagulation products when the TEG values were 35% greater than normal. The results of postoperative coagulation tests for total blood loss and the use of blood products were compared for the 2 groups. When the critical TEG values for transfusion were higher, significantly fewer units of fresh frozen plasma (5.58 6 6.49 versus 11.53 6 6.66 U) and pheresis platelets (1.84 6 1.33 versus 3.55 6 1.43 U) were used. There were no differences in blood loss or postoperative blood product use. In conclusion, the use of higher critical TEG values to initiate the transfusion of plasma-containing products is not associated with increased blood loss. Further testing is necessary to identify what TEG value predicts bleeding due to a deficit in coagulation factors. Liver Transpl 18:1254-1258, 2012. V C 2012 AASLD.Received October 10, 2011; accepted June 13, 2012.Blood transfusions in liver transplant recipients are associated with an increased risk of infection and lung injury.1 This leads to increases in morbidity and mortality.2 Other outcome studies have shown that intraoperative transfusions of plasma products significantly reduce 1-year survival 3-5 and increase morbidity in liver transplant recipients. 6Physicians have used the thromboelastogram (TEG) as a tool for identifying abnormal coagulation. TEG can discriminate between different phases of the coagulation system and is, therefore, useful for identifying clotting abnormalities and guiding the administration of blood products.In 2007, we reported using less frozen plasma in transplant patients when transfusions were guided by standard TEG cutoff values instead of the international normalized ratio (INR)/prothrombin time and platelet counts. 7 We concluded that TEG was a

Pulsatile shear (PS) and oscillatory shear (OS) elicit distinct mechanotransduction signals that maintain endothelial homeostasis or induce endothelial dysfunction, respectively. A subset of microRNAs (miRs) in vascular endothelial cells (ECs) are differentially regulated by PS and OS, but the regulation of the miR processing and its implications in EC biology by shear stress are poorly understood. From a systematic in silico analysis for RNA binding proteins that regulate miR processing, we found that nucleolin (NCL) is a major regulator of miR processing in response to OS and essential for the maturation of miR-93 and miR-484 that target mRNAs encoding Krüppel-like factor 2 (KLF2) and endothelial nitric oxide synthase (eNOS). Additionally, anti-miR-93 and anti-miR-484 restore KLF2 and eNOS expression and NO bioavailability in ECs under OS. Analysis of posttranslational modifications of NCL identified that serine 328 (S328) phosphorylation by AMP-activated protein kinase (AMPK) was a major PS-activated event. AMPK phosphorylation of NCL sequesters it in the nucleus, thereby inhibiting miR-93 and miR-484 processing and their subsequent targeting of KLF2 and eNOS mRNA. Elevated levels of miR-93 and miR-484 were found in sera collected from individuals afflicted with coronary artery disease in two cohorts. These findings provide translational relevance of the AMPK-NCL-miR-93/miR-484 axis in miRNA processing in EC health and coronary artery disease.shear stress | endothelial cells | miRNA | nucleolin | AMPK V ascular endothelium responds differentially to pulsatile and oscillatory shear stresses (PS and OS stresses, respectively) which are athero-protective and athero-prone, respectively. Shear stress acting on vascular endothelial cells (ECs) regulates a plethora of microRNAs (miRs), which in turn positively or negatively affect endothelial function. miR maturation is a multistep process involving highly orchestrated events in both the nucleus and cytoplasm. Following transcription in the nucleus, primary miRs (pri-miRs) containing a stem loop structure undergo two sequential cleavage steps initiated by removal of the 3′ and 5′ terminal ends by Drosha, a component of the microprocessor complex. Subsequently, the premiRs are shuttled from the nucleus to the cytoplasm and become truncated, resulting in singlestranded miRs that are 21-23 nucleotides in length. These mature miRs bind to the miR-induced silencing complex (miRISC) containing an argonaute (AGO) protein that targets mRNAs for degradation via miR seed sequence complementarity. In the context of vascular biology, shear stress-regulated miRs modulate EC proliferation, inflammation, nitric oxide (NO) bioavailability, and intercellular communication (1-6). Although the effects of PS and OS on miRs have been well studied, the mechanistic basis for miR processing in ECs responding to distinct shear stress is unknown.Nucleolin (NCL) is a multidomain protein that shuttles between the nucleus and cytoplasm to coordinate various functions (7). Through four tandem nuc...

The outcomes of living donor liver transplant patients who had fluid therapy guided by an SVV less than 10% were similar to those of patients who were given fluids to reach a CVP of 10 mmHg. Our findings suggest that the two measures of vascular filling are similar in liver transplant recipients with demographic characteristics similar to those of our patients.

Background: Cardiovascular waveforms contain information for clinical diagnosis. By "learning" and organizing the subtle change of waveform morphology from large amounts of raw waveform data, unsupervised manifold learning helps delineate a high-dimensional structure and display it as a novel three-dimensional (3D) image. We hypothesize that the shape of this structure conveys clinically relevant inner dynamics information. Methods:To validate this hypothesis, we investigate the electrocardiography (ECG) waveform for ischemic heart disease and arterial blood pressure (ABP) waveform in dynamic vasoactive episodes. We model each beat or pulse to be a point lying on a manifold, like a surface, and use the diffusion map (DMap) to establish the relationship among those pulses. The output of the DMap is converted to a 3D image for visualization. For ECG datasets, first we analyzed the non-ST-elevation ECG waveform distribution from unstable angina to healthy control in the 3D image, and we investigated intraoperative ST-elevation ECG waveforms to show the dynamic ECG waveform changes. For ABP datasets, we analyzed waveforms collected under endotracheal intubation and administration of vasodilator. To quantify the dynamic separation, we applied the support vector machine (SVM) analysis and reported the total accuracy and macro F1 score. We further carried out the trajectory analysis and derived the moving direction of successive beats (or pulses) as vectors in the high-dimensional space.Results: For the non-ST-elevation ECG, a hierarchical tree structure comprising consecutive ECG waveforms spanning from unstable angina to healthy control is presented in the 3D image (accuracy = 97.6%, macro-F1=96.1%). The DMap helps quantify and visualize the evolving direction of intraoperative ST-elevation myocardial episode in a 1-hour period (accuracy=97.58%, macro-F1=96.06%). The ABP waveform analysis of Nicardipine administration shows inter-individual difference (accuracy=95.01%, macro-F1=96.9%) and their common directions from intra-individual moving trajectories. The dynamic change of the ABP waveform during endotracheal intubation shows a loop-like trajectory structure, which can be further divided using the manifold learning knowledge obtained from Nicardipine. Conclusions:The DMap and the generated 3D image of ECG or ABP waveforms provides clinically relevant inner dynamics information. It provides clues of acute coronary syndrome diagnosis, shows clinical course in myocardial ischemic episode and reveals underneath physiological mechanism under stress or vasodilators.Keywords: manifold learning, diffusion map, electrocardiography, myocardial ischemia, arterial 10,583 ECG beats, including clinical unstable angina (red), ischemic ECG pattern (green), and healthy control (blue). Video F3CCorresponding to Figure 3 panel C, it shows the 3D animation of 1-min ECG beats during the intra-operative ST-elevation event. Video F3DCorresponding to Figure 3 panel D, it shows the 3D animation of 4,299 consecutive ECG 31 beats from the IS...