Mycelium-enhanced bacterial degradation of organic pollutants under bioavailability restrictions

This work examines the role of mycelia in enhancing the degradation by attached bacteria of organic pollutants that have poor bioavailability. Two oomycetes, Pythium oligandrum and Pythium aphanidermatum, were selected as producers of mycelial networks, while Mycobacterium gilvum VM552 served as a model polycyclic aromatic hydrocarbon (PAH)-degrading bacterium. The experiments consisted of bacterial cultures exposed to a non-disturbed non-aqueous phase liquid (NAPL) layer containing a heavy fuel spiked with 14C-labeled phenanthrene that were incubated in the presence or absence of the mycelia of the oomycetes in both shaking and static conditions. At the end of the incubation, the changes in the total alkane and PAH contents in the NAPL residue were quantified. The results revealed that with shaking and the absence of mycelia, the strain VM552 grew by utilizing the bulk of alkanes and PAHs in the fuel; however, biofilm formation was incipient and phenanthrene was mineralized following zero-order kinetics, due to bioavailability limitation. The addition of mycelia favored biofilm formation and dramatically enhanced the mineralization of phenanthrene, up to 30 times greater than the rate without mycelia, possibly by providing a physical support to bacterial colonization and by supplying nutrients at the NAPL/water interface. The results in the static condition were very different because the bacterial strain alone degraded phenanthrene with sigmoidal kinetics but could not degrade alkanes or the bulk of PAHs. We suggest that bacteria/oomycete interactions should be considered not only in the design of new inoculants in bioremediation, but also in biodegradation assessments of chemicals present in natural environments

Combination Therapy of PPARγ Ligands and Inhibitors of Arachidonic Acid in Lung Cancer

Lung cancer is the leading cause of cancer death in the United States and five-year survival remains low. Numerous studies have shown that chronic inflammation may lead to progression of carcinogenesis. As a result of inflammatory stimulation, arachidonic acid (AA) metabolism produces proliferation mediators through complex and dynamic interactions of the products of the LOX/COX enzymes. One important mediator in the activation of the AA pathways is the nuclear protein PPARγ. Targeting LOX/COX enzymes and inducing activation of PPARγ have resulted in significant reduction of cell growth in lung cancer cell lines. However, specific COX-inhibitors have been correlated with an increased cardiovascular risk. Clinical applications are still being explored with a novel generation of dual LOX/COX inhibitors. PPARγ activation through synthetic ligands (TZDs) has revealed a great mechanistic complexity since effects are produced through PPARγ-dependent and -independent mechanisms. Furthermore, PPARγ could also be involved in regulation of COX-2. Overexpression of PPARγ has reported to play a role in control of invasion and differentiation. Exploring the function of PPARγ, in this new context, may provide a better mechanistic model of its role in cancer and give an opportunity to design a more efficient therapeutic approach in combination with LOX/COX inhibitors

Cytokines and Growth Factors Stimulate Hyaluronan Production: Role of Hyaluronan in Epithelial to Mesenchymal-Like Transition in Non-Small Cell Lung Cancer

In this study, we investigated the role of hyaluronan (HA) in non-small cell lung cancer (NSCLC) since close association between HA level and malignancy has been reported. HA is an abundant extracellular matrix component and its synthesis is regulated by growth factors and cytokines that include epidermal growth factor (EGF) and interleukin-1β (IL-1β). We showed that treatment with recombinant EGF and IL-1β, alone or in combination with TGF-β, was able to stimulate HA production in lung adenocarcinoma cell line A549. TGF-β/IL-1β treatment induced epithelial to mesenchymal-like phenotype transition (EMT), changing cell morphology and expression of vimentin and E-cadherin. We also overexpressed hyaluronan synthase-3 (HAS3) in epithelial lung adenocarcinoma cell line H358, resulting in induced HA expression, EMT phenotype, enhanced MMP9 and MMP2 activities and increased invasion. Furthermore, adding exogenous HA to A549 cells and inducing HA H358 cells resulted in increased resistance to epidermal growth factor receptor (EGFR) inhibitor, Iressa. Together, these results suggest that elevated HA production is able to induce EMT and increase resistance to Iressa in NSCLC. Therefore, regulation of HA level in NSCLC may be a new target for therapeutic intervention

Epithelial-to-mesenchymal transition involves triacylglycerol accumulation in DU145 prostate cancer cells

Epithelial to mesenchymal transition (EMT) is a biological process that plays a crucial role in cancer metastasis. Although studies regarding the EMT mechanisms are usual in terms of gene expression and protein functions, little is known about the involvement of lipids in EMT. In this work, an untargeted lipidomic analysis was performed to reveal which lipids are involved in the EMT process. DU145 prostate cancer cells were treated with TNFα, a well-known EMT inducer. After 6 hours of treatment, a decrease of cell membrane E-cadherin as well as a reduction in its gene expression were observed. Also, the mesenchymal markers Vimentin and Snail were up-regulated, suggesting that EMT started below 6 hours of treatment. Lipid extracts of untreated and TNFα-treated cells at short times were analyzed using ultra-performance liquid chromatography coupled to high-resolution mass spectrometry (UPLC-MS). Multivariate data analysis methods were applied to decipher which lipids presented significant changes after EMT induction. Among the results obtained, a significant increase of twelve unsaturated triacylglycerides (TAGs) was observed. This increase of TAGs was also observed for cells treated with TGFβ (another EMT inducer), suggesting that this feature is a common mechanism in the EMT process. In conclusion, this work reported for the first time a TAG accumulation through EMT induction. These TAG lipids could play a key role in providing cells with the energy, cell membrane components and signaling lipids necessary to guarantee the enhanced cell migration and proliferation of metastatic cells.This work was supported by the European Research Council under the European Union’s Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement 320737. J.J acknowledges a CSIC JAE-Doc contract cofounded by FSE.Peer reviewe

Spectroscopic study of the interaction of actinomycin D with oligonucleotides carrying the central base sequences -XGCY- and -XGGCCY- using multivariate methods

10 pages, 5 figures, 1 table.-- PMID: 17123067 [PubMed].-- Published online Nov 23, 2006.Supporting information (4 pages, 3 suppl. figures) available at: http://www.springerlink.com/content/870650451902431q/MediaObjects/216_2006_946_MOESM1_ESM.docThe interactions of actinomycin D (ACTD) with the oligonucleotides 5′-CAAAGCTTTG-3′, 5′-CATGGC CATG-3′ and 5′-TATGGCCATA-3′ were investigated by means of acid–base titrations and mole-ratio and melting experiments monitored by molecular absorption and circular dichroism (CD) spectroscopies. For each experiment, CD and molecular absorption spectra were recorded at each point in the experiment, and later analyzed via appropriate multivariate data analysis methods. The study of the interactions between these oligonucleotides and ACTD at 25°C showed the formation of an interaction complex with a stoichiometry of 1:1 (ACTD:duplex) and values for the log(formation constant) of 5.1 ± 0.3, 6.4 ± 0.2, and 5.6 ± 0.2, respectively. An additional interaction complex at higher temperatures was also detected, which might be related to the single-stranded forms of the oligonucleotides.We acknowledge two grants from the Spanish Ministerio de Educación y Ciencia (projects BFU2004-02048/BMC and BQU2003-0191).Peer reviewe

1H NMR metabolomic study of auxotrophic starvation in yeast using Multivariate Curve Resolution-Alternating Least Squares for Pathway Analysis

Disruption of specific metabolic pathways constitutes the mode of action of many known toxicants and it is responsible for the adverse phenotypes associated to human genetic defects. Conversely, many industrial applications rely on metabolic alterations of diverse microorganisms, whereas many therapeutic drugs aim to selectively disrupt pathogens' metabolism. In this work we analyzed metabolic changes induced by auxotrophic starvation conditions in yeast in a non-targeted approach, using one-dimensional proton Nuclear Magnetic Resonance spectroscopy (1H NMR) and chemometric analyses. Analysis of the raw spectral datasets showed specific changes linked to the different stages during unrestricted yeast growth, as well as specific changes linked to each of the four tested starvation conditions (L-methionine, L-histidine, L-leucine and uracil). Analysis of changes in concentrations of more than 40 metabolites by Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) showed the normal progression of key metabolites during lag, exponential and stationary unrestricted growth phases, while reflecting the metabolic blockage induced by the starvation conditions. In this case, different metabolic intermediates accumulated over time, allowing identification of the different metabolic pathways specifically affected by each gene disruption. This synergy between NMR metabolomics and molecular biology may have clear implications for both genetic diagnostics and drug development. © The Author(s) 2016.The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) / ERC Grant Agreement n. 320737. We also thank Dr. Yolanda Pérez for her helpful recommendations on setting up the acquisition parameters for some of the NMR experiments.Peer reviewe

McTaggart’s Paradox and Philosophy of Time

Asking “What is time?” can be both a simple and a profound question. In this article we intend to introduce the reader to the philosophy of time. To do so, we will deal with McTaggart's paradox. By explaining it and introducing the basic concepts to understand it, we will be able to get an idea of what this branch of philosophy is all about. The main intention of this article is not to explain anything new but to clarify the background of a debate by explaining its roots. By taking a deep dive into the concept of time, we will see that it is not a simple concept at all. In any subsequent possible definition with regards to concepts such time for education or time for ethics, a logical clarification of what time is important and will color all further predication of the concept of time. Considering the impact of digital transformation in our lives in general, and in education in particular, a philosophy of time brings major elements such as paradoxes, which are not of practical character but important for the semantic of the words, such as “duration”, “temporal position” of events, etc

Caracterització i estudi de procedència de l’alabastre del retaule de l’altar major de Poblet

S’ha realitzat la caracterització del material petri usat en l’execució del retaule de l’altar major de Poblet, esculpit en guix alabastrí, des dels punts de vista mineralògic, petrològic i geoquímic, mitjançant l’observació macroscòpica i microscòpica (microscòpia òptica de transmissió electrònica de rastreig) i la difracció de raigs X. Els resultats revelen que aquest alabastre és, en força àrees del retaule, de molt bona qualitat, si bé presenta abundants components que evidencien un descens en la seva puresa en algunes àrees. La caracterització geoquímica d’algunes mostres d’alabastre mitjançant l’estudi de les composicions isotòpiques del sofre i l’oxigen del sulfat del guix, ha permès recolzar analíticament la teoria coneguda documentalment sobre la procedència dels alabastres del retaule de l’altar major de Poblet de la zona de Sarra