510 research outputs found
Simultaneous extraction, derivatisation and analysis of varietal thiols and their non-volatile precursors from beer
Varietal thiols are important contributors to the aroma profile of a wide range of beverages including beer. A methodology for the simultaneous extraction and subsequent analysis of the varietal thiols 3-sulfanylhexan-1-ol (3SH), 3-sulfanylhexylacetate (3SHA) and 4-methyl-4-sulfanylpentan-2-one (4MSP), and the non-volatile precursors 3-S-cysteinylhexan-1-ol (Cys-3SH) and 3-S-glutathionylhexan-1-ol (GSH-3SH) in beer was developed and validated for the first time. The method, which utilises LC-MS/MS, was successfully tested on nine commercial beers, showing it to be widely applicable to this matrix. The syntheses of the novel internal standards d8-3SH and d8-3SHA, which allow a robust and accurate quantification of the hydronated congeners, are also reported. The simplicity of the QuEChERS-based (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction allows for rapid, high throughput analyses suitable for both research and industry application
CD4+ CD25+ FoxP3+ regulatory T cells suppress cytotoxicity of CD8+ effector T cells: implications for their capacity to limit inflammatory central nervous system damage at the parenchymal level
<p>Abstract</p> <p>Background</p> <p>CD4<sup>+ </sup>CD25<sup>+ </sup>forkhead box P3 (FoxP3)<sup>+ </sup>regulatory T cells (T reg cells) are known to suppress adaptive immune responses, key control tolerance and autoimmunity.</p> <p>Methods</p> <p>We challenged the role of CD4<sup>+ </sup>T reg cells in suppressing established CD8<sup>+ </sup>T effector cell responses by using the OT-I/II system <it>in vitro </it>and an OT-I-mediated, oligodendrocyte directed <it>ex vivo </it>model (ODC-OVA model).</p> <p>Results</p> <p>CD4<sup>+ </sup>T reg cells dampened cytotoxicity of an ongoing CD8<sup>+ </sup>T effector cell attack <it>in vitro </it>and within intact central nervous system tissue <it>ex vivo</it>. However, their suppressive effect was limited by the strength of the antigen signal delivered to the CD8<sup>+ </sup>T effector cells and the ratio of regulatory to effector T cells. CD8<sup>+ </sup>T effector cell suppression required T cell receptor-mediated activation together with costimulation of CD4<sup>+ </sup>T reg cells, but following activation, suppression did not require restimulation and was antigen non-specific.</p> <p>Conclusions</p> <p>Our results suggest that CD4<sup>+ </sup>T reg cells are capable of suppressing CD8<sup>+ </sup>T effector cell responses at the parenchymal site, that is, limiting parenchymal damage in autoimmune central nervous system inflammation.</p
Segregation of Regulatory Polymorphisms with Effects on the Gluteus Medius Transcriptome in a Purebred Pig Population
Background: The main goal of the present study was to analyse the genetic architecture of mRNA expression in muscle, a tissue with an outmost economic importance for pig breeders. Previous studies have used F2 crosses to detect porcine expression QTL (eQTL), so they contributed with data that mostly represents the between-breed component of eQTL variation. Herewith, we have analysed eQTL segregation in an outbred Duroc population using two groups of animals with divergent fatness profiles. This approach is particularly suitable to analyse the within-breed component of eQTL variation, with a special emphasis on loci involved in lipid metabolism. Methodology/Principal Findings: GeneChip Porcine Genome arrays (Affymetrix) were used to determine the mRNA expression levels of gluteus medius samples from 105 Duroc barrows. A whole-genome eQTL scan was carried out with a panel of 116 microsatellites. Results allowed us to detect 613 genome-wide significant eQTL unevenly distributed across the pig genome. A clear predominance of trans- over cis-eQTL, was observed. Moreover, 11 trans-regulatory hotspots affecting the expression levels of four to 16 genes were identified. A Gene Ontology study showed that regulatory polymorphisms affected the expression of muscle development and lipid metabolism genes. A number of positional concordances between eQTL and lipid trait QTL were also found, whereas limited evidence of a linear relationship between muscle fat deposition and mRNA levels of eQTL regulated genes was obtained. Conclusions/Significance: Our data provide substantial evidence that there is a remarkable amount of within-breed genetic variation affecting muscle mRNA expression. Most of this variation acts in trans and influences biological processes related with muscle development, lipid deposition and energy balance. The identification of the underlying causal mutations and the ascertainment of their effects on phenotypes would allow gaining a fundamental perspective about how complex traits are built at the molecular level
Multiple populations in globular clusters. Lessons learned from the Milky Way globular clusters
Recent progress in studies of globular clusters has shown that they are not
simple stellar populations, being rather made of multiple generations. Evidence
stems both from photometry and spectroscopy. A new paradigm is then arising for
the formation of massive star clusters, which includes several episodes of star
formation. While this provides an explanation for several features of globular
clusters, including the second parameter problem, it also opens new
perspectives about the relation between globular clusters and the halo of our
Galaxy, and by extension of all populations with a high specific frequency of
globular clusters, such as, e.g., giant elliptical galaxies. We review progress
in this area, focusing on the most recent studies. Several points remain to be
properly understood, in particular those concerning the nature of the polluters
producing the abundance pattern in the clusters and the typical timescale, the
range of cluster masses where this phenomenon is active, and the relation
between globular clusters and other satellites of our Galaxy.Comment: In press (The Astronomy and Astrophysics Review
Watching the city: the politics of space in Pizza, birra, faso
In this article I discuss the representation of Buenos Aires in Pizza, birra, faso. Paying attention to some of the film’s salient aspects vis-a-vis its portrayal of urban space, my analysis has as ultimate goal to reveal the ways in which the film engages in a political critique that might seem absent if studied solely from a narrative point of view. In this sense Pizza, birra, faso is a paradigmatic example of the ways in which many of the films of New Argentine Cinema engaged with their political context differently to films of the post-dictatorship generation. To unearth this political content, I will argue, it is necessary to study these films as films, and not merely texts
Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas
This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing
molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin
Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context
Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts
Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas
Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN
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