NT-proBNP changes in patients with ascites during large volume paracentesis

N-terminal probrain natriuretic peptide (NT-proBNP) is a hormone involved in the regulation of cardiovascular homeostasis. Changes in serum NT-proBNP during large volume paracentesis (LVP) in patients with ascites have never before been examined. Aims. To determine if significant changes in serum NT-proBNP occur in patients undergoing LVP and the associated clinical correlates in patients with cirrhosis. Method. A total of 45 patients with ascites were prospectively recruited. Serum NTproBNP, biochemistry, and haemodynamics were determined at baseline and at key time points during and after paracentesis. Results. 34 patients were analysed; 19 had ascites due to cirrhosis and 15 from malignancy. In those with cirrhosis, NT-proBNP decreased by 77.3 pg/mL at 2 L of drainage and 94.3 pg/mL at the end of paracentesis, compared with an increase of 10.5 pg/mL and 77.2 pg/mL in cancer patients at the same time points ( = 0.05 and = 0.03). Only congestive cardiac failure (CCF) was an independent predictor of significant NT-proBNP changes at the end of drainage in cirrhotic patients ( < 0.01). There were no significant changes in haemodynamics or renal biochemistry for either group. Conclusion. Significant reductions in serum NTproBNP during LVP occur in patients with cirrhosis but notmalignancy, and only comorbid CCF appeared to predict such changes

The influence of pH on antioxidant properties and the mechanism of antioxidant action of hydroxyflavones.

The effect of the pH on antioxidant properties of a series of hydroxyflavones was investigated. The pKa of the individual hydroxyl moieties in the hydroxyflavones was compared to computer-calculated deprotonation energies. This resulted in a quantitative structure activity relationship (QSAR), which enables the estimation of pKa values of individual hydroxyl moieties, also in hydroxyflavones for which these pKa values are not available. Comparison of the pKa values to the pH-dependent antioxidant profiles, determined by the TEAC assay, reveals that for various hydroxyflavones the pH-dependent behavior is related to hydroxyl moiety deprotonation, resulting in an increase of the antioxidant potential upon formation of the deprotonated forms. Comparison of these experimental results to computer calculated O-H bond dissociation energies (BDE) and ionization potentials (IP) of the nondeprotonated and the deprotonated forms of the various hydroxyflavones indicates that especially the parameter reflecting the ease of electron donation, i.e., the IP, and not the BDE, is greatly influenced by the deprotonation. Based on these results it is concluded that upon deprotonation the TEAC value increases (radical scavenging capacity increases) because electron-, not H-, donation becomes easier. Taking into account that the mechanism of radical scavenging antioxidant activity of the neutral form of the hydroxyflavones is generally considered to be hydrogen atom donation, this implies than not only the ease of radical scavenging, but also the mechanism of antioxidant action changes upon hydroxyflavone deprotonation

Cmcgg methylation-independent parent-of-origin effects on genome-wide transcript levels in isogenic reciprocal f1 triploid plants

Triploid F1 hybrids generated via reciprocal interploidy crosses between genetically distinct parental plants can display parent-of-origin effects on gene expression or phenotypes. Reciprocal triploid F1 isogenic plants generated from interploidy crosses in the same genetic background allow investigation on parent-of-origin-specific (parental) genome-dosage effects without confounding effects of hybridity involving heterozygous mutations. Whole-genome transcriptome profiling was conducted on reciprocal F1 isogenic triploid (3x) seedlings of A. thaliana. The genetically identical reciprocal 3x genotypes had either an excess of maternally inherited 3x(m) or paternally inherited 3x(p) genomes. We identify a major parent-of-origin-dependent genome-dosage effect on transcript levels, whereby 602 genes exhibit differential expression between the reciprocal F1 triploids. In addition, using methylation-sensitive DNA tiling arrays, constitutive and polymorphic CG DNA methylation patterns at CCGG sites were analysed, which revealed that paternal-excess F1 triploid seedling C(m)CGG sites are overall hypermethylated. However, no correlation exists between C(m)CGG methylation polymorphisms and transcriptome dysregulation between the isogenic reciprocal F1 triploids. Overall, our study indicates that parental genome-dosage effects on the transcriptome levels occur in paternal-excess triploids, which are independent of C(m)CGG methylation polymorphisms. Such findings have implications for understanding parental effects and genome-dosage effects on gene expression and phenotypes in polyploid plants