987 resultados para reduced nicotinamide adenine dinucleotide phosphate oxidase


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In many species with internal fertilization, molecules transferred in the male ejaculate trigger and interact with physiological changes in females. It is controversial to what extent these interactions between the sexes act synergistically to mediate the female switch to a reproductive state or instead reflect sexual antagonism evolved as a by product of sexual selection on males. To address this question, we eliminated sexual selection by enforcing monogamy in populations of Drosophila melanogaster for 65 generations and then measured the expression of male seminal fluid protein genes and genes involved in the female response to mating. In the absence of sperm competition, male and female reproductive interests are perfectly aligned and any antagonism should be reduced by natural selection. Consistent with this idea, males from monogamous populations showed reduced expression of seminal fluid protein genes, 16% less on average than in polygamous males. Further, we identified 428 genes that responded to mating in females. After mating, females with an evolutionary history of monogamy exhibited lower relative expression of genes that were up regulated in response to mating and higher expression of genes that were down-regulated - in other words, their post-mating transcriptome appeared more virgin-like. Surprisingly, these genes showed a similar pattern even before mating, suggesting that monogamous females evolved to be less poised for mating and the accompanying receipt of male seminal fluid proteins. This reduced investment by both monogamous males and females in molecules involved in post-copulatory interactions points to a pervasive role of sexual conflict in shaping these interactions.

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Hypertension is a major public health problem and a leading cause of death and disability in both developed and developing countries, affecting onequarter of the world"s adult population. Our aim was to evaluate whether the consumption of gazpacho, a Mediterranean vegetable-based cold soup rich in phytochemicals, is associated with lower blood pressure (BP) and/or reduced prevalence of hypertension in individuals at high cardiovascular risk. Methods and results: We selected 3995 individuals (58% women, mean age 67 y) at high cardiovascular risk (81% hypertensive) recruited into the PREDIMED study. BP, weight, and dietary and physical activity data were collected. In multivariate linear regression analyses, after adjustment, moderate and high gazpacho consumption categories were associated with reduced mean systolic BP of 1.9 mm Hg [95% confidence interval (CI): 3.4; 0.6] and 2.6 mm Hg (CI: 4.2; 1.0), respectively, and reduced diastolic BP of 1.5 mm Hg (CI: 2.3; 0.6) and 1.9 mm Hg (CI: 2.8; 1.1). By multiple-adjusted logistic regression analysis, gazpacho consumption was associated with a lower prevalence of hypertension, with OR Z 0.85 (CI: 0.73; 0.99) for each 250 g/week increase and OR Z 0.73 (CI: 0.55; 0.98) for high gazpacho consumption groups compared to the no-consumption group. Conclusions: Gazpacho consumption was inversely associated with systolic and diastolic BP and prevalence of hypertension in a cross-sectional Mediterranean population at high cardiovascular risk. The association between gazpacho intake and reduction of BP is probably due to synergy among several bioactive compounds present in the vegetable ingredients used to make the recipe.

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Hypertension is a major public health problem and a leading cause of death and disability in both developed and developing countries, affecting onequarter of the world"s adult population. Our aim was to evaluate whether the consumption of gazpacho, a Mediterranean vegetable-based cold soup rich in phytochemicals, is associated with lower blood pressure (BP) and/or reduced prevalence of hypertension in individuals at high cardiovascular risk. Methods and results: We selected 3995 individuals (58% women, mean age 67 y) at high cardiovascular risk (81% hypertensive) recruited into the PREDIMED study. BP, weight, and dietary and physical activity data were collected. In multivariate linear regression analyses, after adjustment, moderate and high gazpacho consumption categories were associated with reduced mean systolic BP of 1.9 mm Hg [95% confidence interval (CI): 3.4; 0.6] and 2.6 mm Hg (CI: 4.2; 1.0), respectively, and reduced diastolic BP of 1.5 mm Hg (CI: 2.3; 0.6) and 1.9 mm Hg (CI: 2.8; 1.1). By multiple-adjusted logistic regression analysis, gazpacho consumption was associated with a lower prevalence of hypertension, with OR Z 0.85 (CI: 0.73; 0.99) for each 250 g/week increase and OR Z 0.73 (CI: 0.55; 0.98) for high gazpacho consumption groups compared to the no-consumption group. Conclusions: Gazpacho consumption was inversely associated with systolic and diastolic BP and prevalence of hypertension in a cross-sectional Mediterranean population at high cardiovascular risk. The association between gazpacho intake and reduction of BP is probably due to synergy among several bioactive compounds present in the vegetable ingredients used to make the recipe.

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Conventional (CONV) neuromuscular electrical stimulation (NMES) (i.e., short pulse duration, low frequencies) induces a higher energetic response as compared to voluntary contractions (VOL). In contrast, wide-pulse, high-frequency (WPHF) NMES might elicit-at least in some subjects (i.e., responders)-a different motor unit recruitment compared to CONV that resembles the physiological muscle activation pattern of VOL. We therefore hypothesized that for these responder subjects, the metabolic demand of WPHF would be lower than CONV and comparable to VOL. 18 healthy subjects performed isometric plantar flexions at 10% of their maximal voluntary contraction force for CONV (25 Hz, 0.05 ms), WPHF (100 Hz, 1 ms) and VOL protocols. For each protocol, force time integral (FTI) was quantified and subjects were classified as responders and non-responders to WPHF based on k-means clustering analysis. Furthermore, a fatigue index based on FTI loss at the end of each protocol compared with the beginning of the protocol was calculated. Phosphocreatine depletion (ΔPCr) was assessed using 31P magnetic resonance spectroscopy. Responders developed four times higher FTI's during WPHF (99 ± 37 ×103 N.s) than non-responders (26 ± 12 ×103 N.s). For both responders and non-responders, CONV was metabolically more demanding than VOL when ΔPCr was expressed relative to the FTI. Only for the responder group, the ∆PCr/FTI ratio of WPHF (0.74 ± 0.19 M/N.s) was significantly lower compared to CONV (1.48 ± 0.46 M/N.s) but similar to VOL (0.65 ± 0.21 M/N.s). Moreover, the fatigue index was not different between WPHF (-16%) and CONV (-25%) for the responders. WPHF could therefore be considered as the less demanding NMES modality-at least in this subgroup of subjects-by possibly exhibiting a muscle activation pattern similar to VOL contractions.

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OBJECTIVE: Angiotensin receptor blockers (ARBs) have been suggested to reduce inflammation in randomized controlled trials. We assessed the association between ARBs and inflammatory markers in a general population setting. METHODS: This is a population-based prospective study conducted in Lausanne, Switzerland. Baseline data from 933 participants on antihypertensive drugs (424 on ARBs) was collected in 2003-2006. Follow-up data from 1120 participants (572 on ARBs) was collected in 2009-2012. C-reactive protein (CRP), interleukins 1β and 6 and tumor necrosis factor alpha (TNF-α) were assessed and categorized in quartiles. RESULTS: At baseline, no differences were found between participants taking or not taking ARBs for all inflammatory markers studied, and this association persisted after multivariate adjustment: odds ratios (ORs) and (95% confidence interval) for being in the highest quartile of interleukin-1β, interleukin-6, TNF-α and CRP for participants on ARB compared to participants not on ARB were 1.23 (0.89-1.70), 1.26 (0.93-1.70), 1.14 (0.85-1.53) and 1.27 (0.96-1.69) respectively (P > 0.05). These findings were further replicated in the follow-up study: OR and (95% CI) of 1.10 (0.78-1.55), 0.87 (0.64-1.19), 0.83 (0.61-1.14) and 0.91 (0.68-1.22) for interleukin-1β, interleukin-6, TNF-α and CRP respectively (P > 0.05). Finally, no effect of ARBs was found when comparing participants who received ARBs throughout the 5.4-year follow-up with participants on other antihypertensive drugs: OR and (95% CI) of 0.93 (0.61-1.42), 0.80 (0.54-1.17), 0.86 (0.59-1.25) and 0.95 (0.67-1.35) for interleukin-1β, interleukin-6, TNF-α and CRP respectively (P > 0.05). CONCLUSION: ARBs are not associated with reduced levels of inflammatory markers in the general population.

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Osteoclasts are multinucleated bone degrading cells. Phosphate is an important constituent of mineralized bone and released in significant quantities during bone resorption. Molecular contributors to phosphate transport during the resorptive activity of osteoclasts have been controversially discussed. This study aimed at deciphering the role of sodium-dependent phosphate transporters during osteoclast differentiation and bone resorption. Our studies reveal RANKL-induced differential expression of sodium-dependent phosphate transport protein IIa (NaPi-IIa) transcript and protein during osteoclast development, but no expression of the closely related NaPi-IIb and NaPi-IIc SLC34 family isoforms. In vitro studies employing NaPi-IIa-deficient osteoclast precursors and mature osteoclasts reveal that NaPi-IIa is dispensable for bone resorption and osteoclast differentiation. These results are supported by the analysis of structural bone parameters by high-resolution microcomputed tomography that yielded no differences between adult NaPi-IIa WT and KO mice. By contrast, both type III sodium-dependent phosphate transporters Pit-1 and Pit-2 were abundantly expressed throughout osteoclast differentiation, indicating that they are the relevant sodium-dependent phosphate transporters in osteoclasts and osteoclast precursors. We conclude that phosphate transporters of the SLC34 family have no role in osteoclast differentiation and function and propose that Pit-dependent phosphate transport could be pivotal for bone resorption and should be addressed in further studies.

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OBJECTIVES: Basic calcium phosphate (BCP) crystal and interleukin 6 (IL-6) have been implicated in osteoarthritis (OA). We hypothesise that these two factors may be linked in a reciprocal amplification loop which leads to OA. METHODS: Primary murine chondrocytes and human cartilage explants were incubated with hydroxyapatite (HA) crystals, a form of BCP, and the modulation of cytokines and matrix-degrading enzymes assayed. The ability of IL-6 to stimulate chondrocyte calcification was assessed in vitro. The mechanisms underlying the effects of HA on chondrocytes were investigated using chemical inhibitors, and the pathways mediating IL-6-induced calcification characterised by quantifying the expression of genes involved in chondrocyte mineralisation. The role of calcification in vivo was studied in the meniscectomy model of murine OA (MNX), and the link between IL-6 and cartilage degradation investigated by histology. RESULTS: In chondrocytes, BCP crystals stimulated IL-6 secretion, further amplified in an autocrine loop, through signalling pathways involving Syk and PI3 kinases, Jak2 and Stat3 molecules. Exogenous IL-6 promoted calcium-containing crystal formation and upregulation of genes involved in calcification: the pyrophosphate channel Ank, the calcium channel Annexin5 and the sodium/phosphate cotransporter Pit-1. Treatment of chondrocytes with IL-6 inhibitors significantly inhibited IL-6-induced crystal formation. In meniscectomised mice, increasing deposits of BCP crystals were observed around the joint and correlated with cartilage degradation and IL-6 expression. Finally, BCP crystals induced proteoglycan loss and IL-6 expression in human cartilage explants, which were reduced by an IL-6 inhibitor. CONCLUSIONS: BCP crystals and IL-6 form a positive feedback loop leading to OA. Targeting calcium-containing crystal formation and/or IL-6 are promising therapeutic strategies in OA.

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The response of shoots to phosphate (Pi) deficiency implicates long-distance communication between roots and shoots, but the participating components are poorly understood. We have studied the topology of the Arabidopsis (Arabidopsis thaliana) PHOSPHATE1 (PHO1) Pi exporter and defined the functions of its different domains in Pi homeostasis and signaling. The results indicate that the amino and carboxyl termini of PHO1 are both oriented toward the cytosol and that the protein spans the membrane twice in the EXS domain, resulting in a total of six transmembrane α-helices. Using transient expression in Nicotiana benthamiana leaf, we demonstrated that the EXS domain of PHO1 is essential for Pi export activity and proper localization to the Golgi and trans-Golgi network, although the EXS domain by itself cannot mediate Pi export. In contrast, removal of the amino-terminal hydrophilic SPX domain does not affect the Pi export capacity of the truncated PHO1 in N. benthamiana. While the Arabidopsis pho1 mutant has low shoot Pi and shows all the hallmarks associated with Pi deficiency, including poor shoot growth and overexpression of numerous Pi deficiency-responsive genes, expression of only the EXS domain of PHO1 in the roots of the pho1 mutant results in a remarkable improvement of shoot growth despite low shoot Pi. Transcriptomic analysis of pho1 expressing the EXS domain indicates an attenuation of the Pi signaling cascade and the up-regulation of genes involved in cell wall synthesis and the synthesis or response to several phytohormones in leaves as well as an altered expression of genes responsive to abscisic acid in roots.

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Genetic tools have greatly aided in tracing the sources and colonization history of introduced species. However, recurrent introductions and repeated shuffling of populations may have blurred some of the genetic signals left by ancient introductions. Styela plicata is a solitary ascidian distributed worldwide. Although its origin remains unclear, this species is believed to have spread worldwide by travelling on ship's hulls. The goals of this study were to infer the genetic structure and global phylogeography of S. plicata and to look for present-day and historical genetic patterns. Two genetic markers were used: a fragment of the mitochondrial gene Cytochrome Oxidase subunit I (COI) and a fragment of the nuclear gene Adenine Nucleotide Transporter/ADP-ATP Translocase (ANT). A total of 368 individuals for COI and 315 for ANT were sequenced from 17 locations worldwide. The levels of gene diversity were moderate for COI to high for ANT. The Mediterranean populations showed the least diversity and allelic richness for both markers, while the Indian, Atlantic and Pacific Oceans had the highest gene and nucleotide diversities. Network and phylogenetic analyses with COI and ANT revealed two groups of alleles separated by 15 and 4 mutational steps, respectively. The existence of different lineages suggested an ancient population split. However, the geographic distributions of these groups did not show any consistent pattern, indicating different phylogeographic histories for each gene. Genetic divergence was significant for many population-pairs irrespective of the geographic distance among them. Stochastic introduction events are reflected in the uneven distribution of COI and ANT allele frequencies and groups among many populations. Our results confirmed that S. plicata has been present in all studied oceans for a long time, and that recurrent colonization events and occasional shuffling among populations have determined the actual genetic structure of this species.

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The synthesis of 1-deoxy-D-xylulose 5-phosphate (DXP), catalyzed by the enzyme DXP synthase (DXS), represents a key regulatory step of the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway for isoprenoid biosynthesis. In plants DXS is encoded by small multigene families that can be classified into, at least, three specialized subfamilies. Arabidopsis thaliana contains three genes encoding proteins with similarity to DXS, including the well-known DXS1/CLA1 gene, which clusters within subfamily I. The remaining proteins, initially named DXS2 and DXS3, have not yet been characterized. Here we report the expression and functional analysis of A. thaliana DXS2. Unexpectedly, the expression of DXS2 failed to rescue Escherichia coli and A. thaliana mutants defective in DXS activity. Coherently, we found that DXS activity was negligible in vitro, being renamed as DXL1 following recent nomenclature recommendation. DXL1 is targeted to plastids as DXS1, but shows a distinct expression pattern. The phenotypic analysis of a DXL1 defective mutant revealed that the function of the encoded protein is not essential for growth and development. Evolutionary analyses indicated that DXL1 emerged from DXS1 through a recent duplication apparently specific of the Brassicaceae lineage. Divergent selective constraints would have affected a significant fraction of sites after diversification of the paralogues. Furthermore, amino acids subjected to divergent selection and likely critical for functional divergence through the acquisition of a novel, although not yet known, biochemical function, were identified. Our results provide with the first evidences of functional specialization at both the regulatory and biochemical level within the plant DXS family.

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Here, we report the culture and characterization of an alphaproteobacterium of the order Rhizobiales, isolated from the gut of the honey bee Apis mellifera. Strain PEB0122T shares >95 % 16S rRNA gene sequence similarity with species of the genus Bartonella, a group of mammalian pathogens transmitted by bloodsucking arthropods. Phylogenetic analyses showed that PEB0122T and related strains from the honey bee gut form a sister clade of the genus Bartonella. Optimal growth of strain PEB0122T was obtained on solid media supplemented with defibrinated sheep blood under microaerophilic conditions at 35-37 °C, which is consistent with the cultural characteristics of other species of the genus Bartonella. Reduced growth of strain PEB0122T also occurred under aerobic conditions. The rod-shaped cells of strain PEB0122T had a mean length of 1.2-1.8 μm and revealed hairy surface structures. Strain PEB0122T was positive for catalase, cytochrome c oxidase, urease and nitrate reductase. The fatty acid composition was comparable to those of other species of the genus Bartonella, with palmitic acid (C16 : 0) and isomers of 18- and 19-carbon chains being the most abundant. The genomic DNA G+C content of PEB0122T was determined to be about 45.5 mol%. The high 16S rRNA gene sequence similarity with species of Bartonella and its close phylogenetic position suggest that strain PEB0122T represents a novel species within the genus Bartonella, for which we propose the name Bartonella apis sp. nov. The type strain is PEB0122T ( = NCIMB 14961T = DSM 29779T).

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NLRC5, a member of the NOD-like receptor (NLR) protein family, has recently been characterized as the master transcriptional regulator of MHCI molecules in lymphocytes, in which it is highly expressed. However, its role in activated dendritic cells (DCs), which are instrumental to initiate T cell responses, remained elusive. We show in this study that, following stimulation of DCs with inflammatory stimuli, not only did NLRC5 level increase, but also its importance in directing MHCI transcription. Despite markedly reduced mRNA and intracellular H2-K levels, we unexpectedly observed nearly normal H2-K surface display in Nlrc5(-/-) DCs. Importantly, this discrepancy between a strong intracellular and a mild surface defect in H2-K levels was observed also in DCs with H2-K transcription defects independent of Nlrc5. Hence, alongside with demonstrating the importance of NLRC5 in MHCI transcription in activated DCs, we uncover a general mechanism counteracting low MHCI surface expression. In agreement with the decreased amount of neosynthesized MHCI, Nlrc5(-/-) DCs exhibited a defective capacity to display endogenous Ags. However, neither T cell priming by endogenous Ags nor cross-priming ability was substantially affected in activated Nlrc5(-/-) DCs. Altogether, these data show that Nlrc5 deficiency, despite significantly affecting MHCI transcription and Ag display, is not sufficient to hinder T cell activation, underlining the robustness of the T cell priming process by activated DCs.

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Tumor necrosis factor (TNF)/TNF receptor (TNFR) superfamily members play essential roles in the development of the different phases of the immune response. Mouse LIGHT (TNFSF14) is a type II transmembrane protein with a C-terminus extracellular TNF homology domain (THD) that assembles in homotrimers and regulates the course of the immune responses by signaling through 2 receptors, the herpes virus entry mediator (HVEM, TNFSFR14) and the lymphotoxin β receptor (LTβR, TNFSFR3). LIGHT is a membrane-bound protein transiently expressed on activated T cells, natural killer (NK) cells and immature dendritic cells that can be proteolytically cleaved by a metalloprotease and released to the extracellular milieu. The immunotherapeutic potential of LIGHT blockade was evaluated in vivo. Administration of an antagonist of LIGHT interaction with its receptors attenuated the course of graft-versus-host reaction and recapitulated the reduced cytotoxic activity of LIGHT-deficient T cells adoptively transferred into non-irradiated semiallogeneic recipients. The lack of LIGHT expression on donor T cells or blockade of LIGHT interaction with its receptors slowed down the rate of T cell proliferation and decreased the frequency of precursor alloreactive T cells, retarding T cell differentiation toward effector T cells. The blockade of LIGHT/LTβR/HVEM pathway was associated with delayed downregulation of interleukin-7Rα and delayed upregulation of inducible costimulatory molecule expression on donor alloreactive CD8 T cells that are typical features of impaired T cell differentiation. These results expose the relevance of LIGHT/LTβR/HVEM interaction for the potential therapeutic control of the allogeneic immune responses mediated by alloreactive CD8 T cells that can contribute to prolong allograft survival.

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This work presents a detailed study of the leaching behavior of deactivated hydrotreating catalysts (CoMo, NiMo/Al2O3) in presence of oxalate and NH4+ ions in various media. The yield of metals recovery may be optimized by adjusting several experimental parameters (time, temperature, etc). Leaching is limited by physical factors (diffusional effects caused by coke) and by the existence of silicate/spinel-like species which are poorly soluble in leaching solutions. Coke may be eliminated by an oxidation step at temperatures between 300-400ºC. Above 400ºC, solubilization of Ni and Co is drastically reduced. 50-90% wt of sulphate species and 15-30% wt of phosphate ions are solubilized during leaching. Silicon (as SiO2) is not solubilized. The best Ni-Co-Mo recoveries are in the 70-90% wt range; Fe recovery may be quantitative, whereas Al leaching may be lower than 5% wt.

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The effects of diet composition and ration size on the activities of key enzymes involved in intermediary metabolism were studied in the liver of gilthead sea bream (Sparus aurata). Highcarbohydrate, low-protein diets stimulated 6-phosphofructo 1-kinase (EC 2.7.1.11), pyruvate kinase (EC 2.7.1.40), glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (EC 1.1.1.44) enzyme activities, while they decreased alanine aminotransferase (EC 2.6.1.2) activity. A high degree of correlation was found between food ration size and the activity of the enzymes 6-phosphofructo 1-kinase, pyruvate kinase, glucose-6-phosphate dehydrogenase (positive correlations) and fructose-1,6-bisphosphatase (EC 3.1.3.11) (negative correlation). These correlations matched well with the high correlation also found between ration size and growth rate in starved fish refed for 22 d. Limited feeding (5 g/kg body weight) for 22 d decreased the activities of the key enzymes for glycolysis and lipogenesis, and alanine aminotransferase activity. The findings presented here indicate a high level of metabolic adaptation to both diet type and ration size. In particular, adaptation of enzyme activities to the consumption of a diet with a high carbohydrate level suggests that a carnivorous fish like Sparus aurata can tolerate partial replacement of protein by carbohydrate in the commercial diets supplied in culture. The relationship between enzyme activities, ration size and fish growth indicates that the enzymes quickly respond to dietary manipulations of cultured fish.