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The effect of the application of benzothiadiazole (BTH) and methyl jasmonate (MeJ) at veraison on the phenolic composition of grapes from three varieties (Monastrell, Syrah and Merlot) was studied during the ripening period, using HPLC techniques to measure flavonols, anthocyanins and tannins.; Results: The effects of the treatments differed in the three varieties, and the maximum concentration of phenolic compounds was not always reached at the end of the ripening period but some days before harvest. At the end of ripening both treated Syrah grapes only differed from control grapes in the flavonol concentration, whereas MeJ-treated Merlot grapes presented higher anthocyanin and skin tannin contents than the control and BTH-treated grapes. Only the anthocyanin content was significantly higher in treated Monastrell grapes at the moment of harvest.; Conclusion: The results indicate that the moment of elicitor treatment should be more studied since differences between treated and control grapes were, in general greater several days before harvest in all three varieties. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.

BACKGROUND The microbial fuel cell (MFC) technology transforms the chemical energy present in substrates into electricity. Starting-up these systems, i.e. enriching the anodic community in exoelectrogenic bacteria, is a lengthy process or requires expensive equipment. RESULTS An easy and low-cost procedure based on a sediment MFC was developed to select microbial communities with exoelectrogenic activity from the anaerobic sludge of a waste water treatment plant (WWTP). The configuration was based on a simple vessel working as a single chamber MFC with a cathode of stainless steel wool in the liquid surface and a submerged graphite fibre brush as anode. In 30 days of operation, a biofilm with remarkable exoelectrogenic activity was grown on the anode of the MFC. This graphite fibre brush anode was able to supply 0.9 W m-2 when working in an air-cathode MFC (AC-MFC) for 45 days. CONCLUSION The procedure presented was demonstrated to be a successful, low-cost and low-maintenance procedure to obtain exoelectrogenic activity and had performances comparable with other more costly and complex inoculation procedures. The Sed-MFC does not require a potentiostat, external aeration, stirring, membranes or an enriched inoculum in the exoelectrogenic biomass. © 2013 Society of Chemical Industry

The retinal pigment epithelium (RPE) forms the outer blood-retina barrier (BRB). Most retinal diseases involve BRB breakdown, whereupon thrombin contained in serum directly contacts the RPE. Thrombin is known to promote actin stress fiber formation, an important determinant in eye diseases involving the epithelial-mesenchymal transition (EMT) and migration of RPE cells, such as proliferative vitreoretinopathy. We analyzed thrombin effect on signaling pathways leading to myosin light chain (MLC) phosphorylation and actin stress fiber formation in primary cultures of rat RPE cells, in order to support a role for thrombin in RPE transdifferentiation. MLC phosphorylation was measured by Western blot; actin cytoskeleton was visualized using immunofluorescent phalloidin, and Rho GTPase activation was assessed by ELISA. We showed that thrombin/PAR-1 induces the time- and dose-dependent phosphorylation of MLC through the activation of Rho/ROCK and myosin light chain kinase (MLCK). ROCK increased phospho-MLC by phosphorylating MLC and by inhibiting MLC phosphatase. Thrombin effect was abolished by the ROCK inhibitor Y-27632, whereas MLCK inhibitor ML-7 and PLC-β inhibitor U73122 attenuated MLC phosphorylation by ≈50%, suggesting the activation of MLCK by PLC-β-mediated calcium increase. Additionally, thrombin-induced MLC phosphorylation was blocked by the inhibitory PKCζ pseudosubstrate, wortmannin, and LY294002, indicating IP(3)/PKCζ involvement in the control of MLC phosphorylation. Moreover, we demonstrated that thrombin effect on MLC induces actin stress fiber formation, since this effect was prevented by inhibiting the pathways leading to MLC phosphorylation. We conclude that thrombin stimulation of MLC phosphorylation and actin stress fiber formation may be involved in thrombin-induced RPE cell transformation subsequent to BRB dysfunction.

The oxidative degradation of lipids is one of the main factors limiting the shelf-life of food products. In recent years, several undesirable disorders have been detected as side-effects of using commonly used synthetic antioxidants. Apart from their use as aroma additives in food, essential oils from aromatic plants have shown potential for use in small amounts in fat-containing food systems to prevent or delay some types of chemical deterioration that occur during storage. Using a multiple-method approach, the antioxidant activity of the essentials oils from several spices widely used in Mediterranean countries was tested: oregano (Origanum vulgare), thyme (Thymus vulgaris), rosemary (Rosmarinus officinalis), sage (Salvia officinalis) and clove (Syzygium aromaticum). Their total phenolic compound content was also determined. The clove essential oil had the highest amount of total phenols (898.89 mg/l GAE) and showed the highest percentage inhibition of DPPH radical (98.74%) and the highest FRAP value (1.47 TEAC). The thyme essential oil produced the highest percentage inhibition of TBARS (89.84%). All the essential oils studied were capable of chelating iron(II), the rosemary essential oil producing the highest effect (76.06%) in this respect. The oregano essential oil had the highest antioxidant activity index in the Rancimat test. Copyright © 2009 John Wiley & Sons, Ltd.

The β-amyloid peptide, the major component of Alzheimer-associated plaques, derives from a larger β-amyloid precursor protein (APP), that is expressed in both neural and non-neural cells. Overexpression of APP actively contributes to the development of senile plaques and is considered a risk factor for the disease. APP expression is regulated by a variety of cellular mediators, among them ligands of tyrosine kinase receptors. In this study, we present evidence that brain-derived neurotrophic factor (BDNF) modulates, in a dose- and time-dependent fashion, APP promoter activity in SH-SY5Y neuroblastoma cells transiently expressing the receptor TrkB. The APP promoter contains two potential AP-1 sites, and we examined whether or not protein kinase C (PKC) and the AP-1 sites of the promoter mediate the BDNF-induced stimulation of APP. Stimulation of APP promoter activity by BDNF was not affected by the PKC inhibitor bisindolylmaleimide, or by dominant negative mutants of the AP-1 components Fos and Jun, which, however, blocked the response to phorbol esters. These results suggest that activation of the APP promoter by BDNF is largely independent of PKC and AP-1. In contrast, activated Ras increased APP promoter activity in SH-SY5Y cells, and a dominant negative mutant of Ras abolished BDNF-mediated promoter stimulation. Taken together, our results suggest a mechanism that involves activation of the Ras/MAP kinase signaling pathway, and phosphorylation of as yet unidentified effectors which in turn can activate response elements within the APP promoter.

Brain-derived neurotrophic factor (BDNF) stimulates β-amyloid precursor protein (APP) promoter activity by a Ras-dependent mechanism in TrkB-expressing SH-SY5Y cells. To determine the signalling pathways involved in the BDNF-induced response, we have analysed the ability of TrkB mutated forms to mediate promoter stimulation. Brain-derived neurotrophic factor causes a significant induction of promoter activity and mutation K540R in the active site of TrkB completely abolishes the neurotrophin-induced response. A substitution of the Y484 residue by phenylalanine, which blocks binding of Shc, reduces the activation of APP promoter by BDNF by approximately 50% whereas mutation Y785P, which blocks binding of phospholipase C gamma, does not affect the response. In addition, the phosphatidylinositide 3-kinase (PI3K)-specific inhibitors wortmannin and LY294002 reduced BDNF-induced activation. In agreement with a participation of both Ras/MAPK- and PI3K/Akt-mediated mechanisms, transient expression of constitutive active forms of Ras, PI3K and other components of both signalling pathways led to a significant increase of APP promoter activity. Furthermore, the stimulation of the APP promoter by BDNF was completely precluded by expression of dominant-negative forms of Ras and PI3K effectors. Taken together, our results suggest that simultaneous activation of at least two signalling pathways, Ras/MAPK and PI3K/Akt, is necessary to mediate a full activation of the APP promoter by BDNF.

Pulmonary Langerhans cell histiocytosis (PLCH) affects mainly young, predominantly smoking adults with a peak at 20–40 years of age. Patients with PLCH often present with a nonproductive cough and/or dyspnea. High-resolution CT (HRCT) is the most important diagnostic modality in PLCH. The typical HRCT pattern combines small poorly limited nodules, cavitated nodules, and finally thick- and thin-walled cysts. In rare cases, HRCT enables PLCH to be diagnosed prior to the development of cysts.