Radioactivity distribution to shoots
from root applications measured 43, 30, and 20% of the total absorbed for multi-leaf, one-tiller, and multi-tiller plants, respectively. Smooth crabgrass had two times more foliar absorption of C-14-dithiopyr at 15/10 than 30/25 C while C-14 losses were greater at 30/25 than 15/10 C. Smooth crabgrass metabolism of C-14-dithiopyr was approximate to two times greater at 30/25 than 15/10 C, and multi-leaf plants averaged 10 to 20% more metabolism than tillered plants at 7 d after treatment. Results suggest differential absorption, translocation, and metabolism may contribute to dithiopyr efficacy on smooth crabgrass at various growth stages, but use under high temperatures (30/25 C) could increase losses from volatilization, reduce foliar absorption, and increase metabolism compared Selleckchem LBH589 to cooler temperatures (15/10 C).”
“MPO (myeloperoxidase) catalyses the oxidation of chloride, bromide and thiocyanate by hydrogen peroxide to HOCl (hypochlorous acid), HOBr (hypobromous acid) and HOSCN (hypothiocyanous acid) respectively. Specificity constants indicate that SCN- is a major substrate for MPO. HOSCN is also a major oxidant generated by other peroxidases including salivary, gastric and eosinophil peroxidases. While HOCl and HOBr are powerful oxidizing agents, HOSCN is a less reactive, but more
specific, oxidant which targets thiols and especially low pK(a) species. In the present study we show that HOSCN targets cysteine residues present in PTPs (protein tyrosine phosphatases) with this resulting
in a loss of PTP activity this website for the isolated enzyme, in cell lysates and intact J774A.1 macrophage-like cells. Inhibition also occurs with MPO-generated HOCl and HOBr, but is more marked with MPO-generated HOSCN, particularly at longer incubation times. This inhibition is reversed by dithiothreitol, particularly at early time points, consistent with the reversible oxidation of the active site cysteine residue to give either a cysteine-SCN adduct XMU-MP-1 purchase or a sulfenic acid. Inhibition of PTP activity is associated with increased phosphorylation of p38a and ERK2 (extracellular-signal-regulated kinase 2) as detected by Western blot analysis and phosphoprotein arrays, and results in altered MAPK (mitogen-activated protein kinase) signalling. These data indicate that the highly selective targeting of some protein thiols by HOSCN can result in perturbation of cellular phosphorylation and altered cell signalling. These changes occur with (patho)physiological concentrations of SCN- ions, and implicate HOSCN as an important mediator of inflammation-induced oxidative damage, particularly in smokers who have elevated plasma levels of SCN-.”
“MicroRNAs (miRNAs) are a novel class of short non-coding RNAs, which negatively regulate target gene expression at post-transcriptional level.