NT-proBNP as predictor of major cardiac events after renal transplantation in patients with preserved left ventricular ejection fraction.

BACKGROUND: For the improvement of outcome after renal transplantation it is important to predict future risk of major adverse cardiac events as well as all-cause mortality. We aimed to determine the relationship of pre-transplant NT-proBNP with major adverse cardiac events and all-cause mortality after transplant in patients on the waiting-list with preserved left ventricular ejection fraction. PATIENTS AND METHODS: We included 176 patients with end-stage renal disease and preserved left ventricular ejection fraction who received a kidney transplant. MACE was defined as myocardial infarction (ST-segment elevation [STEMI] or non-ST-segment elevation [NSTEMI]), stroke or transient ischemic attack), coronary artery disease requiring intervention or bypass or death from cardiovascular causes. RESULTS: MACE occurred in 28/176 patients. Patients with NT-proBNP levels above 4350 pg/ml had 1- and 5-year survival rates of 90.67% and 68.20%, whereas patients with NT-proBNP levels below 4350 pg/ml had 1- and 5-year survival rates of 100% and 90.48% (p < 0.01). 1- and 5-year MACE-free survival rates were calculated as 78.82% and 74.68% for patients with NT-proBNP > 4350 pg/ml and 93.33% and 91.21% for patients with NT-proBNP < 4350 pg/ml (p < 0.01). CONCLUSIONS: Pre-transplant NT-proBNP might identify renal transplant candidates at risk for MACE after transplant.

Pre-transplant serum Beta Trace Protein indicates risk for post-transplant major cardiac adverse events.

BACKGROUND: Beta Trace Protein (BTP) is a biomarker for residual kidney function which has been linked to cardiovascular and all-cause mortality in haemodialysis patients. Following renal transplantation, recipients remain at increased risk for cardiovascular events compared with the general population. We aimed to determine the relationship of pre-transplant BTP to major adverse cardiac events (MACE) in patients following kidney transplantation. METHODS: We included 384 patients with end-stage renal disease who received a kidney transplant. MACE was defined as myocardial infarction (ST-segment elevation or non-ST-segment elevation, stroke or transient ischemic attack), coronary artery disease requiring intervention or bypass or death for cardiovascular reason. The association between pre-transplant serum BTP concentration and post-transplant MACE was evaluated by Kaplan-Meier and Cox regression analyses. RESULTS: Post-transplant MACE occurred in 70/384 patients. Pre-transplant BTP was significantly higher in patients with post-transplant MACE (14.36 ± 5.73 mg/l vs. 11.26 ± 5.11 mg/l; p < .01). Next to smoking (HR 1.81), age > 56.38 years (HR 1.97) and pre-existing coronary heart disease (HR 8.23), BTP above the cut off value of 12.7 mg/l was confirmed as independent risk factor for MACE (HR 2.02, all p < .05). MACE-free survival inversely correlated with pre-transplant BTP levels. CONCLUSIONS: Pre-transplant serum BTP concentration may identify renal transplant recipients with higher risk of post-transplant MACE.

A Systematic Review of the Ornamental Fish Trade with Emphasis on Coral Reef Fishes-An Impossible Task.

The multi-billion dollar trade in ornamental fishes has rarely been reliably monitored. Almost all coral reef fishes are wild-caught, and few scientific analyses have attempted to elicit exact quantities and identify species involved. The consequences of the removal of millions of these fishes are poorly understood. This article collates and examines available information, including scientific studies and formal publications, in order to create a more accurate picture of this commerce. We demonstrate that it is almost impossible to analyse the trade in marine ornamental fishes due to a lack of data, and that available data for marine species is frequently combined with that for freshwater species. Figures range from 15 to 30 million coral reef fishes being traded annually, but could be as high as 150 million specimens. The global value of this trade was only estimated for 1976 and 1999 between USD 28-40 million. This review highlights the urgent need to introduce a specific harmonised system tariff code and for a global monitoring system, such as the Trade Control and Expert System already in use in Europe, in order to gather accurate and timely information on the number and species of marine ornamental fishes in commerce, where specimens originated, and whether they were wild-caught or captive-bred.

Principles and characteristics of the Arabidopsis WRKY regulatory network during early MAMP-triggered immunity.

During microbe-associated molecular pattern-triggered immunity more than 5000 Arabidopsis genes are significantly altered in their expression, and the question arises, how such an enormous reprogramming of the transcriptome can be regulated in a safe and robust manner? For the WRKY transcription factors (TFs), which are important regulators of numerous defense responses, it appears that they act in a complex regulatory sub-network rather than in a linear fashion, which would be much more vulnerable to gene function loss either by pathogen-derived effectors or by mutations. In this study we employed RNA-seq, mass spectrometry and chromatin immunoprecipitation-seq to find evidence for and uncover principles and characteristics of this network. Upon flg22-treatment, one can distinguish between two sets of WRKY genes: constitutively expressed and induced WRKY genes. Prior to elicitation the induced WRKY genes appear to be maintained in a repressed state mainly by the constitutively expressed WRKY factors, which themselves appear to be regulated by non-WRKY TFs. Upon elicitation, induced WRKYs rapidly bind to induced WRKY gene promoters and by auto- and cross-regulation build up the regulatory network. Maintenance of this flg22-induced network appears highly robust as removal of three key WRKY factors can be physically and functionally compensated for by other WRKY family members.

Prospective cohort studies of beta-trace protein and mortality in haemodialysis patients and patients undergoing coronary angiography.

Background: Beta-trace protein (BTP) is a low-molecular-weight glycoprotein, which may serve as an endogenous biomarker of kidney function and cardiovascular risk. Methods: We examined cardiovascular and all-cause mortality according to BTP concentrations in 2962 individuals referred for coronary angiography from the Ludwigshafen Risk and Cardiovascular Health study and in 907 patients with Type 2 diabetes mellitus undergoing haemodialysis from the German Diabetes and Dialysis (4D) study. Results: Haemodialysis patients had considerably higher median (interquartile range) BTP concentrations [6.00 (4.49-7.96) mg/L] and experienced a 4-fold increased mortality rate compared with coronary angiography patients [BTP concentration: 0.55 (0.44-0.67) mg/L]. After adjustment for age, sex, cardiovascular risk factors and creatinine, 4D patients in the highest quartile (>7.96 mg/L) had a 1.6-fold increased rate of all-cause mortality [hazard ratio (HR) 1.62, 95% confidence interval (CI) 1.19-2.20] compared with the lowest quartile (<4.49 mg/L) (P = 0.002) In patients undergoing coronary angiography, the adjusted HRs (95% CI) for all-cause and cardiovascular mortality were 1.23 (1.0-1.51) and 1.27 (0.99-1.63) in the highest (>0.67 mg/L) compared with the lowest (<0.44 mg/L) quartile (P = 0.043 and 0.062). In both cohorts, the BTP/creatinine ratio was a stronger predictor of all-cause and cardiovascular mortality compared with BTP. Conclusion: BTP was associated with all-cause mortality independently of renal function in haemodialysis patients. The BTP/creatinine ratio was more predictive for all-cause and cardiovascular mortality in haemodialysis patients and individuals referred for angiography compared with BTP as single marker.

Comparison of Targeted Mass Spectrometry Techniques with an Immunoassay: A Case Study for HSP90α.

PURPOSE: The objective of this study is to better understand factors governing the variability and sensitivity in SRM and PRM, compared to immunoassay. EXPERIMENTAL DESIGN: A 2D-LC-MS/MS-based SRM and PRM assay is developed for quantitative measurements of HSP90α in serum. Forty-three control sera are compared by SRM, PRM, and ELISA following the manufacturer's instructions. Serum samples are trypsin-digested and fractionated by strong cation exchange chromatography prior to SRM and PRM measurements. Analytical parameters such as linearity, LOD, LOQ, repeatability, and reproducibility of the SRM, PRM, and ELISA are determined. RESULTS: PRM data obtained by high-resolution MS correlate better with ELISA measurements than SRM data measured on a triple quadrupole mass spectrometer. While all three methods (SRM, PRM, and ELISA) are able to quantify HSP90α in serum at the ng mL-1 level, the use of PRM on a high-resolution mass spectrometer reduces variation and shows comparable sensitivity to immunoassay. CONCLUSIONS AND CLINICAL RELEVANCE: Using fractionation, it is possible to measure ng mL-1 levels of HSP90α in a reproducible, selective, and sensitive way using PRM in serum. This opens up the possibility to use PRM in a multiplexed way as an attractive alternative for immunoassays without the use of antibodies or comparable binders.

Botrytis cinerea B05.10 promotes disease development in Arabidopsis by suppressing WRKY33-mediated host immunity.

The large WRKY transcription factor family is mainly involved in regulating plant immune responses. Arabidopsis WRKY33 is a key transcriptional regulator of hormonal and metabolic processes towards Botrytis cinerea strain 2100 infection and is essential for resistance. In contrast to B. cinerea strain 2100, the strain B05.10 is virulent on wild-type (WT) Col-0 Arabidopsis plants highlighting the genetic diversity within this pathogen species. We analysed how early WRKY33-dependent responses are affected upon infection with strain B05.10 and found that most of these responses were strongly dampened during this interaction. Ectopic expression of WRKY33 resulted in complete resistance towards this strain indicating that virulence of B05.10, at least partly, depends on suppressing WRKY33 expression/protein accumulation. As a consequence, the expression levels of direct WRKY33 target genes, including those involved in the biosynthesis of camalexin, were also reduced upon infection. Concomitantly, elevated levels of the phytohormone abscisic acid (ABA) were observed. Molecular and genetic studies revealed that ABA negatively influences defence to B05.10 and effects jasmonic acid/ethylene (JA/ET) and salicylic acid (SA) levels. Susceptibility/resistance was determined by the antagonistic effect of ABA on JA, and this crosstalk required suppressing WRKY33 functions at early infection stages. This indicates that B. cinerea B05.10 promotes disease by suppressing WRKY33-mediated host defences.

Transcriptional events defining plant immune responses.

Rapid and massive transcriptional reprogramming upon pathogen recognition is the decisive step in plant-phytopathogen interactions. Plant transcription factors (TFs) are key players in this process but they require a suite of other context-specific co-regulators to establish sensory transcription regulatory networks to bring about host immunity. Molecular, genetic and biochemical studies, particularly in the model plants Arabidopsis and rice, are continuously uncovering new components of the transcriptional machinery that can selectively impact host resistance toward a diverse range of pathogens. Moreover, detailed studies on key immune regulators, such as WRKY TFs and NPR1, are beginning to reveal the underlying mechanisms by which defense hormones influence the function of these factors. Here we provide a short update on such recent developments.

Neutrophil gelatinase-associated lipocalin levels are U-shaped in the Ludwigshafen Risk and Cardiovascular Health (LURIC) study-Impact for mortality.

INTRODUCTION: Neutrophil gelatinase-associated lipocalin (NGAL) is a glycoprotein released by damaged renal tubular cells and mature neutrophils. It is elevated in kidney injury, but also in patients with coronary artery disease (CAD) and myocardial infarction. We investigated the prognostic value of NGAL for total and cardiovascular mortality in patients undergoing coronary angiography without history of renal insufficiency at inclusion into the study. PARTICIPANTS: The LURIC study is an ongoing prospective cohort study of patients referred for coronary angiography and is designed to evaluate determinants of cardiovascular health. RESULTS: NGAL was determined in plasma of 2997 persons (mean age: 62.7 years; 69.7% men) with a follow up for 10 years. 2358 patients suffered from CAD and 638 did not-these patients served as controls. Stable CAD was found in 1408 and unstable CAD in 950 patients. Death rate from cardiovascular events and all causes was highest in patients within the 4th quartile of NGAL (≥56 ng/ml, p<0.001 vs third quartile), even after adjustment for age and gender. According to multivariable-adjusted Cox analysis adjusting for well-known cardiovascular risk factors, as well as lipid lowering therapy, angiographic CAD, and C-reactive protein we found patients in the highest NGAL quartile being at increased risk for cardiovascular (hazard ratio (HR) 1.33, 95%CI 1.05-1.67, p = 0.016) and all cause mortality (HR 1.29 95%CI 1.07-1.55, p = 0.007) compared to those in the third quartile. The lowest risk was seen in the third quartile of NGAL (41-56 ng/ml) suggesting a U-shaped relationship between NGAL and mortality. Further adjustment for creatinine abrogated the predictive effect of NGAL. However, the 3rd and 4th quartiles of NGAL were significantly associated with higher neutrophil counts, which were associated with CAD, non-ST elevation and ST-elevation myocardial infarction (p<0.05). CONCLUSIONS: Plasma NGAL concentrations are mainly derived from neutrophils and do not predict mortality independent of renal function.

Induced Genome-Wide Binding of Three Arabidopsis WRKY Transcription Factors during Early MAMP-Triggered Immunity.

During microbial-associated molecular pattern-triggered immunity (MTI), molecules derived from microbes are perceived by cell surface receptors and upon signaling to the nucleus initiate a massive transcriptional reprogramming critical to mount an appropriate host defense response. WRKY transcription factors play an important role in regulating these transcriptional processes. Here, we determined on a genome-wide scale the flg22-induced in vivo DNA binding dynamics of three of the most prominent WRKY factors, WRKY18, WRKY40, and WRKY33. The three WRKY factors each bound to more than 1000 gene loci predominantly at W-box elements, the known WRKY binding motif. Binding occurred mainly in the 500-bp promoter regions of these genes. Many of the targeted genes are involved in signal perception and transduction not only during MTI but also upon damage-associated molecular pattern-triggered immunity, providing a mechanistic link between these functionally interconnected basal defense pathways. Among the additional targets were genes involved in the production of indolic secondary metabolites and in modulating distinct plant hormone pathways. Importantly, among the targeted genes were numerous transcription factors, encoding predominantly ethylene response factors, active during early MTI, and WRKY factors, supporting the previously hypothesized existence of a WRKY subregulatory network. Transcriptional analysis revealed that WRKY18 and WRKY40 function redundantly as negative regulators of flg22-induced genes often to prevent exaggerated defense responses.

High-urgency kidney transplantation in the Eurotransplant Kidney Allocation System: success or waste of organs? The Eurotransplant 15-year all-centre survey.

BACKGROUND: In the Eurotransplant Kidney Allocation System (ETKAS), transplant candidates can be considered for high-urgency (HU) status in case of life-threatening inability to undergo renal replacement therapy. Data on the outcomes of HU transplantation are sparse and the benefit is controversial. METHODS: We systematically analysed data from 898 ET HU kidney transplant recipients from 61 transplant centres between 1996 and 2010 and investigated the 5-year patient and graft outcomes and differences between relevant subgroups. RESULTS: Kidney recipients with an HU status were younger (median 43 versus 55 years) and spent less time on the waiting list compared with non-HU recipients (34 versus 54 months). They received grafts with significantly more mismatches (mean 3.79 versus 2.42; P < 0.001) and the percentage of retransplantations was remarkably higher (37.5 versus 16.7%). Patient survival (P = 0.0053) and death with a functioning graft (DwFG; P < 0.0001) after HU transplantation were significantly worse than in non-HU recipients, whereas graft outcome was comparable (P = 0.094). Analysis according to the different HU indications revealed that recipients listed HU because of an imminent lack of access for dialysis had a significantly worse patient survival (P = 0.0053) and DwFG (P = 0.0462) compared with recipients with psychological problems and suicidality because of dialysis. In addition, retransplantation had a negative impact on patient and graft outcome. CONCLUSIONS: Facing organ shortages, increasing wait times and considerable mortality on dialysis, we question the current policy of HU allocation and propose more restrictive criteria with regard to individuals with vascular complications or repeated retransplantations in order to support patients on the non-HU waiting list with a much better long-term prognosis.

Negative regulation of ABA signaling by WRKY33 is critical for Arabidopsis immunity towards Botrytis cinerea 2100.

The Arabidopsis mutant wrky33 is highly susceptible to Botrytis cinerea. We identified >1680 Botrytis-induced WRKY33 binding sites associated with 1576 Arabidopsis genes. Transcriptional profiling defined 318 functional direct target genes at 14 hr post inoculation. Comparative analyses revealed that WRKY33 possesses dual functionality acting either as a repressor or as an activator in a promoter-context dependent manner. We confirmed known WRKY33 targets involved in hormone signaling and phytoalexin biosynthesis, but also uncovered a novel negative role of abscisic acid (ABA) in resistance towards B. cinerea 2100. The ABA biosynthesis genes NCED3 and NCED5 were identified as direct targets required for WRKY33-mediated resistance. Loss-of-WRKY33 function resulted in elevated ABA levels and genetic studies confirmed that WRKY33 acts upstream of NCED3/NCED5 to negatively regulate ABA biosynthesis. This study provides the first detailed view of the genome-wide contribution of a specific plant transcription factor in modulating the transcriptional network associated with plant immunity.

A dual inhibitor of matrix metalloproteinases and a disintegrin and metalloproteinases, [¹8F]FB-ML5, as a molecular probe for non-invasive MMP/ADAM-targeted imaging.

BACKGROUND: Numerous clinical studies have shown a correlation between increased matrix metalloproteinase (MMP)/a disintegrin and metalloproteinase (ADAM) activity and poor outcome of cancer. Various MMP inhibitors (MMPIs) have been developed for therapeutic purposes in oncology. In addition, molecular imaging of MMP/ADAM levels in vivo would allow the diagnosis of tumors. We selected the dual inhibitor of MMPs and ADAMs, ML5, which is a hydroxamate-based inhibitor with affinities for many MMPs and ADAMs. ML5 was radiolabelled with (18)F and the newly obtained radiolabelled inhibitor was evaluated in vitro and in vivo. MATERIALS AND METHODS: ML5 was radiolabelled by direct acylation with N-succinimidyl-4-[(18)F]fluorobenzoate ([(18)F]SFB) for PET (positron emission tomography). The resulting radiotracer [(18)F]FB-ML5 was evaluated in vitro in human bronchial epithelium 16HBE cells and breast cancer MCF-7 cells. The non-radioactive probe FB-ML5 and native ML5 were tested in a fluorogenic inhibition assay against MMP-2, -9, -12 and ADAM-17. The in vivo kinetics of [(18)F]FB-ML5 were examined in a HT1080 tumor-bearing mouse model. Specificity of probe binding was examined by co-injection of 0 or 2.5mg/kg ML5. RESULTS: ML5 and FB-ML5 showed high affinity for MMP-2, -9, -12 and ADAM-17; indeed IC50 values were respectively 7.4 ± 2.0, 19.5 ± 2.8, 2.0 ± 0.2 and 5.7 ± 2.2 nM and 12.5 ± 3.1, 31.5 ± 13.7, 138.0 ± 10.9 and 24.7 ± 2.8 nM. Radiochemical yield of HPLC-purified [(18)F]FB-ML5 was 13-16% (corrected for decay). Cellular binding of [(18)F]FB-ML5 was reduced by 36.6% and 27.5% in MCF-7 and 16 HBE cells, respectively, after co-incubation with 10 µM of ML5. In microPET scans, HT1080 tumors exhibited a low and homogeneous uptake of the tracer. Tumors of mice injected with [(18)F]FB-ML5 showed a SUVmean of 0.145 ± 0.064 (n=6) which decreased to 0.041 ± 0.027 (n=6) after target blocking (p<0.05). Ex vivo biodistribution showed a rapid excretion through the kidneys and the liver. Metabolite assays indicated that the parent tracer represented 23.2 ± 7.3% (n=2) of total radioactivity in plasma, at 90 min post injection (p.i.). CONCLUSION: The nanomolar affinity MMP/ADAM inhibitor ML5 was successfully labelled with (18)F. [(18)F]FB-ML5 demonstrated rather low binding in ADAM-17 overexpressing cell lines. [(18)F]FB-ML5 uptake showed significant reduction in the HT1080 tumor in vivo after co-injection of ML5. [(18)F]FB-ML5 may be suitable for the visualization/quantification of diseases overexpressing simultaneously MMPs and ADAMs.

Cystatin C is independently associated with total and cardiovascular mortality in individuals undergoing coronary angiography. The Ludwigshafen Risk and Cardiovascular Health (LURIC) study.

AIMS: Cystatin C is a well established marker of kidney function. There is evidence that cystatin C concentrations are also associated with mortality. The present analysis prospectively evaluated the associations of cystatin C with all-cause and cardiovascular (CV) mortality in a well-characterized cohort of persons undergoing angiography, but without overt renal insufficiency. METHODS: Cystatin C was available in 2998 persons (mean age: 62.7 ± 10.5 years; 30.3% women). Of those 2346 suffered from coronary artery disease (CAD) and 652 (controls) did not. Creatinine (mean ± SD: 83.1 ± 47.8 vs. 74.1 ± 24.7 µmol/L, p = 0.036) but not Cystatin C (mean ± SD: 1.02 ± 0.44 vs. 0.92 ± 0.26 mg/L, p = 0.065) was significantly higher in patients with CAD. After a median follow-up of 9.9 years, in total 898 (30%) deaths occurred, 554 (18.5%) due to CV disease and 326 (10.9%) due to non-CV causes. Multivariable-adjusted Cox analysis (adjusting for eGFR and established cardiovascular risk factors, lipid lowering therapy, angiographic coronary artery disease, and C-reactive protein) revealed that patients in the highest cystatin C quartile were at an increased risk for all-cause (hazard ratio (HR) 1.93, 95% CI 1.50-2.48) and CV mortality (HR 2.05 95% CI 1.48-2.84) compared to those in the lowest quartile. The addition of cystatin C to a model consisting of established cardiovascular risk factors increased the area under the receiver-operating characteristic curve for CV and all-cause mortality, but the difference was statistically not significant. However, reclassification analysis revealed significant improvement by addition of cystatin C for CV and all-cause mortality (p < 0.001), respectively. CONCLUSION: The concentration of cystatin C is strongly associated with long-term all-cause and cardiovascular mortality in patients referred to coronary angiography, irrespective of creatinine-based renal function.

Functional dissection of the PROPEP2 and PROPEP3 promoters reveals the importance of WRKY factors in mediating microbe-associated molecular pattern-induced expression.

· In Arabidopsis thaliana, small peptides (AtPeps) encoded by PROPEP genes act as damage-associated molecular patterns (DAMPs) that are perceived by two leucine-rich repeat receptor kinases, PEPR1 and PEPR2, to amplify defense responses. In particular, expression of PROPEP2 and PROPEP3 is strongly and rapidly induced by AtPeps, in response to bacterial, oomycete, and fungal pathogens, and microbe-associated molecular patterns (MAMPs). · The cis-regulatory modules (CRMs) within the PROPEP2 and PROPEP3 promoters that mediate MAMP responsiveness were delineated, employing parsley (Petroselinum crispum) protoplasts and transgenic A. thaliana plants harboring promoter-reporter constructs. By chromatin immunoprecipitation in vivo, DNA interactions with a specific transcription factor were detected. Furthermore, the PHASTCONS program was used to identify conserved regions of the PROPEP3 locus in different Brassicaceae species. · The major MAMP-responsive CRM within the PROPEP2 promoter is composed of several W boxes and an as1/OCS (activation sequence-1/octopine synthase) enhancer element, while in the PROPEP3 promoter the CRM is comprised of six W boxes. The WRKY33 transcription factor binds in vivo to these promoter regions in a MAMP-dependent manner. Both the position and orientation of the six W boxes are conserved within the PROPEP3 promoters of four other Brassicaceae family members. · WRKY factors are the major regulators of MAMP-induced PROPEP2 and PROPEP3 expression.

Chemical labeling of electrochemically cleaved peptides.

RATIONALE: Cleavage of peptide bonds C-terminal to tyrosine and tryptophan after electrochemical oxidation may become a complementary approach to chemical and enzymatic cleavage. A chemical labeling approach specifically targeting reactive cleavage products is presented here and constitutes a promising first step towards the development of a new proteomics workflow. METHODS: Hexylamine was used to react with the spirolactone moieties generated after electrochemical oxidation and cleavage of tripeptides. The influence of pH and reaction time on the yield was determined and the excess of tagging reagent was optimized. Selective detection of the tagged cleavage products was achieved by precursor ion scanning in a triple quadrupole mass spectrometer. RESULTS: Optimal labeling was reached under aqueous conditions when working at pH 10 with a reaction time of 0.5 min. The excess of hexylamine over spirolactone groups can be significantly decreased by working under non-aqueous conditions in pure acetonitrile to prevent spirolactone hydrolysis. The specific formation of hexylamine-containing y(1) reporter ions generated by collision-induced dissociation (CID) tandem mass spectrometry (MS/MS) allows for selective detection by precursor ion scanning of the cleaved and labeled peptides. CONCLUSIONS: This work presents a method for selective labeling and detection of electrochemically cleaved Tyr- and Trp-containing peptides for which reaction conditions have been optimized with hexylamine as labeling agent. This workflow offers new possibilities for electrochemical oxidation, cleavage and labeling of peptides and proteins.

The effect of hemodialysis on liver stiffness measurement: a single-center series.

BACKGROUND/AIMS: The noninvasive measurement of liver stiffness using transient elastography (TE) is increasingly being used alongside liver biopsy. However, several conditions may lead to higher liver stiffness values without reflecting more fibrosis. Such conditions (e.g. hepatitis, cholestasis, heart failure, mechanical ventilation) limit the interpretation of liver stiffness measurements. The influence of hemodialysis on the measurement of liver stiffness has not been investigated to date. Here, we analyzed liver stiffness assessed by fibroscan in 17 patients directly before and after a hemodialysis session. PATIENTS AND METHODS: Measurement of hepatic stiffness by TE was carried out using the Fibroscan device with the 'M probe' directly before and directly after one session of hemodialysis. Each measurement consisted of at least 10 individual and valid measurements, with a success rate of at least 60%, and an interquartile range of less than 25%. All measurements were carried out by one investigator not involved in patient management. RESULTS: Before dialysis, the median TE was 5.1 kPa (2.8-17 kPa). Ten patients had values below the threshold of 7.1 kPa and seven patients had TE>7.1 kPa. The median net fluid withdrawal by hemodialysis was 2.5 l (0.4-3.1 l) and did not differ between patients. After dialysis, the TE median was 7.4 kPa (3.5-12.5 kPa) and had changed in all patients except one. Liver stiffness increased significantly when the initial TE was lower than 7.1 kPa (P=0.05), but not when the initial TE was higher than 7.1 kPa. Furthermore, the magnitude of the change in TE after hemodialysis correlated inversely with the liver stiffness before hemodialysis (P=0.03) and with spleen length measured by ultrasound (P=0.03). CONCLUSION: This study is the first to report on the influence of hemodialysis on liver stiffness measurement. In contrast to previous reports, liver stiffness might increase after fluid withdrawal if patients do not show significant fibrosis. We conclude that before dialysis, TE possibly better differentiates between patients with or without significant fibrosis.

Arabidopsis WRKY33 is a key transcriptional regulator of hormonal and metabolic responses toward Botrytis cinerea infection.

The Arabidopsis (Arabidopsis thaliana) transcription factor WRKY33 is essential for defense toward the necrotrophic fungus Botrytis cinerea. Here, we aimed at identifying early transcriptional responses mediated by WRKY33. Global expression profiling on susceptible wrky33 and resistant wild-type plants uncovered massive differential transcriptional reprogramming upon B. cinerea infection. Subsequent detailed kinetic analyses revealed that loss of WRKY33 function results in inappropriate activation of the salicylic acid (SA)-related host response and elevated SA levels post infection and in the down-regulation of jasmonic acid (JA)-associated responses at later stages. This down-regulation appears to involve direct activation of several jasmonate ZIM-domain genes, encoding repressors of the JA-response pathway, by loss of WRKY33 function and by additional SA-dependent WRKY factors. Moreover, genes involved in redox homeostasis, SA signaling, ethylene-JA-mediated cross-communication, and camalexin biosynthesis were identified as direct targets of WRKY33. Genetic studies indicate that although SA-mediated repression of the JA pathway may contribute to the susceptibility of wrky33 plants to B. cinerea, it is insufficient for WRKY33-mediated resistance. Thus, WRKY33 apparently directly targets other still unidentified components that are also critical for establishing full resistance toward this necrotroph.

Dependence of ß3-adrenergic signaling on the adipokine leptin in cardiac myocytes.

ß3-Adrenergic receptors (ß3ARs) negatively regulate ß-adrenergic signaling via nitric oxide and are dependent on the adipokine leptin for normal expression in adipocytes, thus making ß3AR an attractive candidate for cross-talk with leptin in the heart. Accordingly, we tested the hypothesis that cardiac ß3AR expression and function are dependent on leptin and are severely diminished in leptin-deficient ob/ob mice. Using isolated cardiac myocyte physiology studies, we found that ß3AR function was significantly diminished in ob/ob myocytes and in wild-type myocytes treated with leptin antagonist. This finding was supported by quantitative PCR demonstrating markedly decreased ß3AR mRNA levels in ob/ob mice. Both ß3AR mRNA and function were restored in ob/ob mice after in vivo leptin repletion. We propose that diminished ß3AR signaling may be the critical element to explain the direct effects of leptin on the myocardium and suggest that this work reveals a key feature in the role of leptin in obesity-related cardiac hypertrophy and heart failure.

Is beta-trace protein an alternative marker of glomerular filtration rate in liver transplant recipients?

BACKGROUND: Renal insufficiency is common after liver transplantation (LT). The use of creatinine (Crea) as a marker of the glomerular filtration rate (GFR) is limited in patients after LT. Beta-trace protein (BTP), an alternative marker of GFR, is independent of muscle mass and has not been evaluated in LT recipients. AIM: To evaluate BTP as an alternative tool to monitor renal function in LT recipients. METHODS: We determined the diagnostic performance of BTP in comparison to Crea and cystatin C (CysC) in 52 patients, who concomitantly underwent (99m)Tc-DTPA-clearance measurements. Furthermore, we evaluated bias, precision and accuracy of five recently developed BTP-based equations to estimate GFR. RESULTS: The average measured GFR was 51 (46.1; 56.0) ml/min/1.73 m(2). Using a cut-off of 30 ml/min/1.73 m(2) the area under the curve (AUC) was nearly identical for all markers. At a decision point of 60 ml/min/1.73 m(2) BTP showed only a trend towards a higher AUC compared with Crea and CysC (0.806 vs. 0.754 and 0.760, respectively; P>0.2). In comparison to the modification of diet in renal disease-formula (MDRD) only one of five BTP-based equations displayed a significantly higher accuracy within 30% of the measured GFR (84.6 vs. 59.6%; P=0.006). None of these equations showed a significant improvement compared with MDRD with respect to bias and precision. CONCLUSIONS: Beta-trace protein can be used as an alternative diagnostic tool to detect moderate or severe GFR reduction in patients after LT. Furthermore BTP-based equations are able to estimate GFR in LT recipients. However, these equations fail to perform constantly better than the MDRD formula.