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In the past two decades, novel preservation technologies have been investigated to achieve sufficient microbial reduction while improving the quality of food and beverages. The effect of UV-C light (UV-C, 1720 mJ/cm2) assisted by mild heat (H, 50 °C) on the inactivation and the physiological state of Candida parapsilosis ATCC 22019 in a carrot-orange juice was studied by flow cytometry. Additionally, the juice samples processed or not (control) by the single (UV-C; H) and combined (UV-C/H) treatments were analyzed for total polyphenol content (TPC), total antioxidant activity (TAA), color, turbidity, °Brix, pH, and pectin methylesterase units (PME) along 13–24-day storage (4 °C). Consumer-profiling studies were conducted on UV-C/H and a pasteurized juice. UV-C/H was highly effective in reducing C. parapsilosis by 5.5 log cycles, whereas the single UV-C and H treatments induced 2.9 and 3.9 log reductions, respectively. Flow cytometry revealed a shift with time from cells with intact membrane and esterase activity to those with permeabilized membrane and without esterase activity, which was significantly higher for UV-C/H samples (98.0%) compared with the single treatments (12.0–46.2%). UV-C/H preserved juice color, pH, °Brix, and turbidity of the juice, which exhibited equal TAA (0.7 mg/mL) and higher TPC (302.1 μg/mL) than the control (TAA = 0.7 mg/mL/TPC = 205.0 μg/mL), remaining constant throughout storage. PME decreased 42–45% for the H and UV-C/H treatments, respectively. A cluster sensory analysis revealed that one group of consumers showed a remarkable interest in the UV-C/H juice, while the conjoint study showed that it was perceived as very healthy. The CATA question determined that the UV-C/H processing prevented the juice from being perceived too particulate or with cooked or artificial taste, as happened with the pasteurized juice. [ABSTRACT FROM AUTHOR]

We investigated the transfer of conditioned avoidance functions through equivalence relations, and the extinction of these functions, facilitated by verbal prompts. Nine participants acquired three 4-member stimulus equivalence classes using a matching-to-sample procedure. One class stimulus was paired, by classical conditioning, with an aversive tone, which was used in avoidance training of a distinct response. There were two groups: A established the equivalence classes before avoidance training and vice versa for B. During some avoidance trials, each stimulus presentation was followed by the request for a verbal estimation of the probability of the tone. The last trials, run in extinction, included a verbal prompt to corroborate the provided estimation. One participant in each group received no verbal prompts. To negate the necessary reliance on instructions-governed performance, an additional participant completed the experiment with minimal instructions. All participants who had the equivalence training prior to the conditioning showed within-class transfer of avoidance functions, in contrast to the others. All prompted participants who demonstrated transfer showed gradual response extinction, but with a differential gradient. Responding decreased more sharply to the indirectly related stimuli than to the directly paired stimuli. The clinical implications are discussed. [ABSTRACT FROM AUTHOR]

In this paper we deal with the local null controllability of the N-dimensional Navier-Stokes system with internal controls having one vanishing component. The novelty of this work is that no condition is imposed on the control domain. [ABSTRACT FROM AUTHOR]

Background: Kallikrein-related peptidases (KLKs) are a family of serine proteases that have been shown to be dysregulated in several malignancies including ovarian cancer. The control of kallikrein genes and their physiological function in cancer is not well understood. We hypothesized that microRNAs (miRNAs) represent a novel mechanism for post-transcriptional control of KLK expression in cancer.Methods: We first analysed miRNA expression in ovarian cancer in silico. A total of 98 miRNAs were reported to have altered expression in ovarian cancer. Three of these miRNAs were predicted to target KLK10. We experimentally verified the predicted miR-KLK10 interaction using two independent techniques, a luciferase assay with a construct containing the KLK10 3' untranslated region (UTR), pMIR-KLK10, and measuring KLK10 protein levels after transfection with miRNA.Results: When we co-transfected cells with pMIR-KLK10 and either let-7f, miR-224, or mR-516a, we saw decreased luciferase signal, suggesting that these miRNAs can target KLK10. We then examined the effect of these three miRNAs on KLK10 protein expression and cell growth. Transfection of all miRNAs, let-7f, miR-224, and miR-516a led to a decrease in protein expression and cellular growth. This effect was shown to be dose dependent. The KLK10 protein levels were partially restored by co-transfecting let-7f and its inhibitor. In addition, there was a slight decrease in KLK10 mRNA expression after transfection with let-7f.Conclusion: Our results confirm that KLKs can be targeted by more than one miRNA. Increased expression of certain miRNAs in ovarian cancer can lead to decreased KLK protein expression and subsequently have a negative effect on cell proliferation. This dose-dependent effect suggests that a 'tweaking' or 'fine-tuning' mechanism exists in which the expression of one KLK can be controlled by multiple miRNAs. These data together suggest that miRNA may be used as potential therapeutic options and further studies are required. [ABSTRACT FROM AUTHOR]

The preferential oxidation of carbon monoxide in the presence of hydrogen (PROX reaction) was studied on Cu catalysts promoted with Fe, Nb, Ce, and Ni supported on TiO2 and on TiO2 nanotubes. The surface area of the untreated TiO2 anatase (150 m2/g) support was increase to 350 m2/g when transformed into TiO2 nanotubes (NT). XRD and SEM results confirm the formation of nanotubular structures responsible of the increase in BET surface area. The activity results indicate that a 10% Cu/5% Nb/TiO2-NT catalyst is highly active for this reaction compared to other transition metals and with a catalyst with the same composition supported on untreated TiO2. We found close to 80% CO conversion and 40% selectivity to CO2 formation at 170 °C. The higher activity is ascribed to a higher dispersion of Cu on the TiO2 NT structures. [ABSTRACT FROM AUTHOR]

The amino acid analogue selenomethionine (SeMet) is shown to be efficiently incorporated into recombinant proteins expressed in Escherichia coli grown in a simple minimal medium without the addition of synthetic amino acids. Furthermore, satisfactory SeMet incorporation is obtained with a methionine-prototrophic strain transformed with commonly used vector systems. As examples, purified tryparedoxin 1 from Crithidia fasciculata, alkylhydroperoxide reductase (AhpC) from Mycobacterium marinum and the 16-kDa antigen from M. tuberculosis are shown to be efficiently labelled with SeMet, using the culture conditions and the host/vector systems described here. Enzymatic analysis reveals no differences between native and SeMet-labelled tryparedoxin 1 enzyme. Both proteins yield crystals under similar conditions. The culture conditions and host vector systems described greatly facilitate selenium-labelling of proteins for 3-D structure determination. [ABSTRACT FROM AUTHOR]

Tryparedoxin peroxidase has recently been identified as a constituent of the complex peroxidase system in the trypanosomatid Crithidia fasciculata [Nogoceke E, Gommel DU, Kiess M, Kalisz HM, Flohé L (1997) Biol Chem 378: 827–836]. In trypanosomatids, hydroperoxides are reduced at the expense of NADPH by means of a cascade of three oxidoreductases: the flavoprotein trypanothione reductase, tryparedoxin and tryparedoxin peroxidase. Inhibitors of these enzymes are presumed to be trypanocidal drugs. Here, we present the heterologous expression of a putative tryparedoxin peroxidase gene of Trypanosoma cruzi (accession no AJ012101) as an N-terminally His-tagged protein (TcH6TXNPx). The product was purified with a high yield (8.75 mg from 1 l fermentation broth of A600 2.1) from the cytosolic fraction of sonified Escherichia coli BL21(DE3)[pET22b(+)/TcH6TXNPx] by metal-chelating chromatography. TcH6TXNPx proved to be fully active when tested with heterologous tryparedoxins of C. fasciculata (His-tagged TXN1H6 and TXN2H6). TcH6TXNPx displayed ping-pong kinetics with a kcat of 1.7 s-1 and limiting Km values of 51.8 μM and 1.7 μM for t-butyl hydroperoxide and CfTXN2H6, respectively. [ABSTRACT FROM AUTHOR]