Genetic- or transforming growth factor-beta 1-induced changes in epidermal peroxisome proliferator-activated receptor beta/delta expression dictate wound repair kinetics.

Advances in wound care are of great importance in clinical injury management. In this respect, the nuclear receptor peroxisome proliferator-activated receptor (PPAR)beta/delta occupies a unique position at the intersection of diverse inflammatory or anti-inflammatory signals that influence wound repair. This study shows how changes in PPARbeta/delta expression have a profound effect on wound healing. Using two different in vivo models based on topical application of recombinant transforming growth factor (TGF)-beta1 and ablation of the Smad3 gene, we show that prolonged expression and activity of PPARbeta/delta accelerate wound closure. The results reveal a dual role of TGF-beta1 as a chemoattractant of inflammatory cells and repressor of inflammation-induced PPARbeta/delta expression. Also, they provide insight into the so far reported paradoxical effects of the application of exogenous TGF-beta1 at wound sites.

Price Transmission and Effects of Exchange Rates on Domestic Commodity Prices via Offshore and Currency Hedging

The framework presents how trading in the foreign commodity futures market and the forward exchange market can affect the optimal spot positions of domestic commodity producers and traders. It generalizes the models of Kawai and Zilcha (1986) and Kofman and Viaene (1991) to allow both intermediate and final commodities to be traded in the international and futures markets, and the exporters/importers to face production shock, domestic factor costs and a random price. Applying mean-variance expected utility, we find that a rise in the expected exchange rate can raise both supply and demand for commodities and reduce domestic prices if the exchange rate elasticity of supply is greater than that of demand. Whether higher volatilities of exchange rate and foreign futures price can reduce the optimal spot position of domestic traders depends on the correlation between the exchange rate and the foreign futures price. Even though the forward exchange market is unbiased, and there is no correlation between commodity prices and exchange rates, the exchange rate can still affect domestic trading and prices through offshore hedging and international trade if the traders are interested in their profit in domestic currency. It illustrates how the world prices and foreign futures prices of commodities and their volatility can be transmitted to the domestic market as well as the dynamic relationship between intermediate and final goods prices. The equilibrium prices depends on trader behaviour i.e. who trades or does not trade in the foreign commodity futures and domestic forward currency markets. The empirical result applying a two-stage-least-squares approach to Thai rice and rubber prices supports the theoretical result.

The Delta of Ebro: economic uses and changes in the ecosystems

El Delta del Ebro se halla situado en el Mediterráneo, en NE de la Península Ibérica (sur de Cataluña). Su formación ha sido resultado de la interacción del mar y del Ebro, un río que con sus 910 km de longitud drena una cuenca de unos 85.362 km2. Sus características dependen de los diferentes regímenes climáticos de su extensa cuenca, lo que explica la complejidad de su régimen. A lo largo del periodo estudiado el Delta fue siempre una realidad geológica aunque experimentó importantes cambios en su morfología. En consecuencia, sus recursos naturales siempre pudieron ser explotados, aunque estas actividades se hubieron de adaptar a su cambiante morfología y a sus peculiares condiciones naturales, diferentes de las zonas terrestres más inmediatas.

Alpha beta lineage-committed thymocytes can be rescued by the gamma delta T cell receptor (TCR) in the absence of TCR beta chain.

Commitment of the alpha beta and gamma delta T cell lineages within the thymus has been studied in T cell receptor (TCR)-transgenic and TCR mutant murine strains. TCR gamma delta-transgenic or TCR beta knockout mice, both of which are unable to generate TCR alpha beta-positive T cells, develop phenotypically alpha beta-like thymocytes in significant proportions. We provide evidence that in the absence of functional TCR beta protein, the gamma delta TCR can promote the development of alpha beta-like thymocytes, which, however, do not expand significantly and do not mature into gamma delta T cells. These results show that commitment to the alpha beta lineage can be determined independently of the isotype of the TCR, and suggest that alpha beta versus gamma delta T cell lineage commitment is principally regulated by mechanisms distinct from TCR-mediated selection. To accommodate our data and those reported previously on the effect of TCR gamma and delta gene rearrangements on alpha beta T cell development, we propose a model in which lineage commitment occurs independently of TCR gene rearrangement.

Els primers llums del Delta

Treball de recerca realitzat per un alumne d'ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l'any 2009. El treball és un estudi de l’evolució, tan tècnica com estètica dels fars paral•lela als avenços tecnològics i prenent com a protagonistes els singulars fars de ferro que es varen construir durant la segona meitat del segle XIX i varen funcionar durant un llarguíssim període en el delta de l’Ebre. L’estructura de ferro, ancorada directament sobre les sorres del delta va donar un caràcter especial a aquestes construccions que, d’altra banda, constituïen una tipologia única a Catalunya i a Espanya. Aquests fars van rebre el nom del lloc on foren ubicats estratègicament. De sud a nord: far de la Banya, far de Buda i far del Fangar. Els van projectar conjuntament, es van encendre per primera vegada el mateix dia, van ser l’habitatge dels seus faroners, van anar evolucionant tècnicament tots tres però el final de cadascun d’ells va ser molt diferent. La història dels fars de ferro ha anat lligada al paisatge i la vida d’aquestes singulars terres del Delta i després de més d’un segle de servei foren substituïts per altres que estèticament i tècnicament res tenen a veure amb els seus antecessors.

Differential involvement of peroxisome-proliferator-activated receptors alpha and delta in fibrate and fatty-acid-mediated inductions of the gene encoding liver fatty-acid-binding protein in the liver and the small intestine.

Liver fatty-acid-binding protein (L-FABP) is a cytoplasmic polypeptide that binds with strong affinity especially to long-chain fatty acids (LCFAs). It is highly expressed in both the liver and small intestine, where it is thought to have an essential role in the control of the cellular fatty acid (FA) flux. Because expression of the gene encoding L-FABP is increased by both fibrate hypolipidaemic drugs and LCFAs, it seems to be under the control of transcription factors, termed peroxisome-proliferator-activated receptors (PPARs), activated by fibrate or FAs. However, the precise molecular mechanism by which these regulations take place remain to be fully substantiated. Using transfection assays, we found that the different PPAR subtypes (alpha, gamma and delta) are able to mediate the up-regulation by FAs of the gene encoding L-FABP in vitro. Through analysis of LCFA- and fibrate-mediated effects on L-FABP mRNA levels in wild-type and PPARalpha-null mice, we have found that PPARalpha in the intestine does not constitute a dominant regulator of L-FABP gene expression, in contrast with what is known in the liver. Only the PPARdelta/alpha agonist GW2433 is able to up-regulate the gene encoding L-FABP in the intestine of PPARalpha-null mice. These findings demonstrate that PPARdelta can act as a fibrate/FA-activated receptor in tissues in which it is highly expressed and that L-FABP is a PPARdelta target gene in the small intestine. We propose that PPARdelta contributes to metabolic adaptation of the small intestine to changes in the lipid content of the diet.

Transcriptional profiling reveals divergent roles of PPARalpha and PPARbeta/delta in regulation of gene expression in mouse liver.

Little is known about the role of the transcription factor peroxisome proliferator-activated receptor (PPAR) beta/delta in liver. Here we set out to better elucidate the function of PPARbeta/delta in liver by comparing the effect of PPARalpha and PPARbeta/delta deletion using whole genome transcriptional profiling and analysis of plasma and liver metabolites. In fed state, the number of genes altered by PPARalpha and PPARbeta/delta deletion was similar, whereas in fasted state the effect of PPARalpha deletion was much more pronounced, consistent with the pattern of gene expression of PPARalpha and PPARbeta/delta. Minor overlap was found between PPARalpha- and PPARbeta/delta-dependent gene regulation in liver. Pathways upregulated by PPARbeta/delta deletion were connected to innate immunity and inflammation. Pathways downregulated by PPARbeta/delta deletion included lipoprotein metabolism and various pathways related to glucose utilization, which correlated with elevated plasma glucose and triglycerides and reduced plasma cholesterol in PPARbeta/delta-/- mice. Downregulated genes that may underlie these metabolic alterations included Pklr, Fbp1, Apoa4, Vldlr, Lipg, and Pcsk9, which may represent novel PPARbeta/delta target genes. In contrast to PPARalpha-/- mice, no changes in plasma free fatty acid, plasma beta-hydroxybutyrate, liver triglycerides, and liver glycogen were observed in PPARbeta/delta-/- mice. Our data indicate that PPARbeta/delta governs glucose utilization and lipoprotein metabolism and has an important anti-inflammatory role in liver. Overall, our analysis reveals divergent roles of PPARalpha and PPARbeta/delta in regulation of gene expression in mouse liver.

Peroxisomal Delta(3),Delta(2)-enoyl CoA isomerases and evolution of cytosolic paralogues in embryophytes

Delta(3),Delta(2)-enoyl CoA isomerase (ECI) is an enzyme that participates in the degradation of unsaturated fatty acids through the beta-oxidation cycle. Three genes encoding Delta(3),Delta(2)-enoyl CoA isomerases and named AtECI1, AtECI2 and AtECI3 have been identified in Arabidopsis thaliana. When expressed heterologously in Saccharomyces cerevisiae, all three ECI proteins were targeted to the peroxisomes and enabled the yeast Deltaeci1 mutant to degrade 10Z-heptadecenoic acid, demonstrating Delta(3),Delta(2)-enoyl CoA isomerase activity in vivo. Fusion proteins between yellow fluorescent protein and AtECI1 or AtECI2 were targeted to the peroxisomes in onion epidermal cells and Arabidopsis root cells, but a similar fusion protein with AtECI3 remained in the cytosol for both tissues. AtECI3 targeting to peroxisomes in S. cerevisiae was dependent on yeast PEX5, while expression of Arabidopsis PEX5 in yeast failed to target AtECI3 to peroxisomes. AtECI2 and AtECI3 are tandem duplicated genes and show a high level of amino acid conservation, except at the C-terminus; AtECI2 ends with the well conserved peroxisome targeting signal 1 (PTS1) terminal tripeptide PKL, while AtECI3 possesses a divergent HNL terminal tripeptide. Evolutionary analysis of ECI genes in plants revealed several independent duplication events, with duplications occurring in rice and Medicago truncatula, generating homologues with divergent C-termini and no recognizable PTS1. All plant ECI genes analyzed, including AtECI3, are under negative purifying selection, implying functionality of the cytosolic AtECI3. Analysis of the mammalian and fungal genomes failed to identify cytosolic variants of the Delta(3),Delta(2)-enoyl CoA isomerase, indicating that evolution of cytosolic Delta(3),Delta(2)-enoyl CoA isomerases is restricted to the plant kingdom

Validación del delta base déficit como modelo predictor de resultados en pacientes politraumáticos. Hospital Parc Taulí Sabadell. Estudio preliminar

Les escales de valoració al pacient politraumàtic són essencials per al seu maneig i pronòstic. Podem definir índexs de gravetat o probabilitat de supervivència. Segons quins paràmetres analitzi, podem parlar d’escales fisiològiques, anatòmiques, bioquímiques i els índexs de probabilitat de supervivència. El BISS és un model de probabilitat provat a Holanda que ha demostrat ser objectiu. El nostre treball consisteix en la validació del BISS als nostres pacients. Durant dos anys vàrem recollir 354 pacients podent incloure només 167 al nostre estudi. Els resultats van ser significatius amb l’estudi posterior, però degut a la gran pèrdua de pacients no podem afirmar la nostra hipòtesi.

Reacción a "Pyricularia grisea" de las variedades más importantes de arroz cultivadas en el Delta del Ebro, durante el período 2000-2008

La pyriculariosis del arroz, causada por el hongo Pyricularia grisea (Cooke) Sacc., es una enfermedad que provoca daños considerables en la zona arrocera del Delta del Ebro. El hongo puede infectar el cultivo en todos los estadios de crecimiento y también en las partes aéreas de la planta: hoja, nudo del tallo, cuello y panícula. El uso de variedades resistentes para el control de la enfermedad es un método económico y efectivo, pero esta resistencia puede verse modificada con la presencia en la zona de nuevas poblaciones de P. grisea de tipo virulento, por lo que esta herramienta se debe utilizar bajo un concepto dinámico. El presente trabajo se centra en el estudio del comportamiento frente a P. grisea de un grupo de variedades de arroz cultivadas en el Delta del Ebro durante el período 2000-2008. El perfil varietal del Delta del Ebro durante este período ha ido variando constantemente y la mayoría de variedades principales que se han cultivado o se cultivan actualmente han presentado un comportamiento de tipo moderado frente a P. grisea.