441 research outputs found

    Differential effects of canopy manipulation and shading of Vitis vinifera L. cv. Cabernet Sauvignon. Leaf gas exchange, photosynthetic electron transport rate and sugar accumulation in berries

    Get PDF
    Partial cluster and leaf removals were performed on Vitis vinifera L. cv. Cabernet Sauvignon at veraison during two years to give 4 treatments: control (C), cluster thinning (CT), leaf removal (LR) and cluster thinning + leaf removal (CT+LR). A half of each plot was shaded by a 50 % shading net at veraison (40 % berries coloured). Shading significantly reduced stomatal conductance but not CO2 assimilation rate (Pn) and carboxylation efficiency. Pn was decreased by cluster thinning and enhanced by leaf removal. Leaves of CT vines showed a photosynthetic decay 2 days after the treatment while LR leaves presented an afternoon photosynthetic enhancement 3 days after the treatment probably due to a higher photoassimilate requirement of the bunches (sink). Stomatal conductance did not totally contribute to the P-n depression or enhancement. Electron transport rate and maximum Rubisco activity were strongly affected by CT and LR suggesting that photochemical and biochemical processes were affected to a greater extent than physical processes. Juice sugar concentration was reduced by shading, an effect explained straightforwardly by the lessening of stomatal conductance. CT and LR had large effects on biochemical and photochemical processes but these were in the opposite direction to the expected effects on juice sugar concentration. It is suggested that CT increased sugar concentration because of the low fruit sink load per vine, and that LR decreased sugar concentration because of the low leaf area per vine. If cluster thinning is to be used by growers to gain increased sugar concentration it is recommended to do it at veraison; the sugar accumulation rate is then high and the adaptation of photosynthetic processes to thinning takes several days

    What is Feminist About Open Access?: A Relational Approach to Copyright in the Academy

    Get PDF
    In a context of great technological and social change, existing intellectual property regimes such as copyright must contend with parallel forms of ownership and distribution. Proponents of open access question and undermine the paradigm of exclusivity central to traditional copyright law, thereby fundamentally challenging its ownership structures and the publishing practices these support. In this essay, we attempt to show what it is about the open access endeavour that resonates with a feminist theory of law and society - in other words, we consider what is “feminist” about open access. First, we provide an overview of a relational feminist critique of traditional copyright law and the assumptions of possessive individualism that pervade it. We then offer a brief description of the open access movement and the way in which it reflects or responds to this criticism. In doing so, we discover vital synergies between this branch of feminist legal theory and the open access movement. Ultimately, we hope to underscore the importance of an open access policy for legal journals such as this one, whose mission is to support, advance and disseminate a feminist perspective that challenges the prevailing hegemony within traditional legal scholarship. We conclude by offering ways in which this journal can help draw out the synergies between feminist criticism and the open access movement

    What is Feminist About Open Access?: A Relational Approach to Copyright in the Academy

    Get PDF
    In a context of great technological and social change, existing intellectual property regimes such as copyright must contend with parallel forms of ownership and distribution. Proponents of open access question and undermine the paradigm of exclusivity central to traditional copyright law, thereby fundamentally challenging its ownership structures and the publishing practices these support. In this essay, we attempt to show what it is about the open access endeavour that resonates with a feminist theory of law and society - in other words, we consider what is “feminist” about open access. First, we provide an overview of a relational feminist critique of traditional copyright law and the assumptions of possessive individualism that pervade it. We then offer a brief description of the open access movement and the way in which it reflects or responds to this criticism. In doing so, we discover vital synergies between this branch of feminist legal theory and the open access movement. Ultimately, we hope to underscore the importance of an open access policy for legal journals such as this one, whose mission is to support, advance and disseminate a feminist perspective that challenges the prevailing hegemony within traditional legal scholarship. We conclude by offering ways in which this journal can help draw out the synergies between feminist criticism and the open access movement

    Serum Amyloid P Component (SAP)-Like Protein From Botryllid Ascidians Provides a Clue to Amyloid Function

    Get PDF
    The HA-1 lectin isolated from Botrylloides leachii has an amino acid composition similar to that of mammalian serum amyloid protein (SAP). SAP is a universal component of mammalian amyloid deposits. Like SAP, HA-1 has a disc ultrastructure, and antibody to HA-1 binds both (a) to amyloidlike fibers deposited between rejected Botrylloides colonies and (b) to cerebral amyloid deposits in Alzheimer's disease brains. Deposition of protochordate amyloid within rejection sites and surrounding fouling organisms implies that these fibers function as barriers to allogeneic and infectious challenge. Similarly, mammalian amyloid may also function to contain inflammatory lesions and to limit the spread of certain infections. Pathological amyloidotic conditions in humans, such as Alzheimer's disease, may result from unregulated expression of this primitive encapsulation response

    Transdifferentiation of pancreatic progenitor cells to hepatocyte-like cells is not serum-dependent when facilitated by extracellular matrix proteins

    Get PDF
    The rising prevalence of chronic liver disease, coupled with a permanent shortage of organs for liver transplantation, has sparked enormous interest in alternative treatment strategies. Previous protocols to generate hepatocyte-like cells (HLCs) via pancreas-to-liver transdifferentiation have utilised fetal bovine serum, introducing unknown variables and severely limiting study reproducibility. Therefore, the main goal of this study was to develop a protocol for transdifferentiation of pancreatic progenitor cells to HLCs in a chemically defined, serum-free culture medium. The clonal pancreatic progenitor cell line AR42J-B13 was cultured in basal growth medium on uncoated plastic culture dishes in the absence or presence of Dexamethasone on uncoated, laminin-or fibronectin-coated culture substrata, with or without serum supplementation. The hepatocytic differentiation potential was evaluated: (i) morphologically through bright-field and scanning electron microscopy, (ii) by assessing pancreatic and hepatic marker expression and (iii) by determining the function of HLCs through their ability to synthesise glycogen or take up and release indocyanine green. Here we demonstrate for the first time that transdifferentiation of pancreatic cells to HLCs is not dependent on serum. These results will assist in converting current differentiation protocols into procedures that are compliant with clinical use in future cell-based therapies to treat liver-related metabolic disorders

    What's Feminist About Open Access? A Relational Approach to Copyright in the Academy

    Get PDF
    In a context of great technological and social change, existing intellectual property regimes such as copyright must contend with parallel forms of ownership and distribution. Proponents of open access, for example, question and undermine the paradigm of exclusivity central to traditional copyright law, thereby fundamentally challenging its ownership structures and the publishing practices these support. In this essay, we attempt to show what it is about the open access endeavour that resonates with a feminist theory of law and society—in other words, we consider what is “feminist” about open access.  First, we provide an overview of a relational feminist critique of traditional copyright law and the assumptions of possessive individualism that pervade it.  We then offer a brief description of the open access movement and the way in which it reflects or responds to this criticism. In doing so, we discover vital synergies between this branch of feminist legal theory and the open access movement. Ultimately, we hope to underscore the importance of an open access policy for legal journals such as this one, whose mission is to support, advance and disseminate a feminist perspective that challenges the prevailing hegemony within traditional legal scholarship. We conclude by offering ways in which this journal can help draw out the synergies between feminist criticism and the open access movement

    Transcriptome profiling of grapevine seedless segregants during berry development reveals candidate genes associated with berry weight

    Get PDF
    Indexación: Web of Science; PubMedBackground Berry size is considered as one of the main selection criteria in table grape breeding programs. However, this is a quantitative and polygenic trait, and its genetic determination is still poorly understood. Considering its economic importance, it is relevant to determine its genetic architecture and elucidate the mechanisms involved in its expression. To approach this issue, an RNA-Seq experiment based on Illumina platform was performed (14 libraries), including seedless segregants with contrasting phenotypes for berry weight at fruit setting (FST) and 6–8 mm berries (B68) phenological stages. Results A group of 526 differentially expressed (DE) genes were identified, by comparing seedless segregants with contrasting phenotypes for berry weight: 101 genes from the FST stage and 463 from the B68 stage. Also, we integrated differential expression, principal components analysis (PCA), correlations and network co-expression analyses to characterize the transcriptome profiling observed in segregants with contrasting phenotypes for berry weight. After this, 68 DE genes were selected as candidate genes, and seven candidate genes were validated by real time-PCR, confirming their expression profiles. Conclusions We have carried out the first transcriptome analysis focused on table grape seedless segregants with contrasting phenotypes for berry weight. Our findings contributed to the understanding of the mechanisms involved in berry weight determination. Also, this comparative transcriptome profiling revealed candidate genes for berry weight which could be evaluated as selection tools in table grape breeding programs.http://bmcplantbiol.biomedcentral.com/articles/10.1186/s12870-016-0789-

    In vitro expansion of keratinocytes on human dermal fibroblast-derived matrix retains their stem-like characteristics

    Get PDF
    The long-term expansion of keratinocytes under conditions that avoid xenogeneic components (i.e. animal serum- and feeder cell-free) generally causes diminished proliferation and increased terminal differentiation. Here we present a culture system free of xenogeneic components that retains the self-renewal capacity of primary human keratinocytes. In vivo the extracellular matrix (ECM) of the tissue microenvironment has a major influence on a cell's fate. We used ECM from human dermal fibroblasts, cultured under macromolecular crowding conditions to facilitate matrix deposition and organisation, in a xenogeneic-free keratinocyte expansion protocol. Phospholipase A2 decellularisation produced ECM whose components resembled the core matrix composition of natural dermis by proteome analyses. Keratinocytes proliferated rapidly on these matrices, retained their small size, expressed p63, lacked keratin 10 and rarely expressed keratin 16. The colony forming efficiency of these keratinocytes was enhanced over that of keratinocytes grown on collagen I, indicating that dermal fibroblast-derived matrices maintain the in vitro expansion of keratinocytes in a stem-like state. Keratinocyte sheets formed on such matrices were multi-layered with superior strength and stability compared to the single-layered sheets formed on collagen I. Thus, keratinocytes expanded using our xenogeneic-free protocol retained a stem-like state, but when triggered by confluence and calcium concentration, they stratified to produce epidermal sheets with a potential clinical use

    A Real Time Metridia Luciferase Based Non-Invasive Reporter Assay of Mammalian Cell Viability and Cytotoxicity via the β-actin Promoter and Enhancer

    Get PDF
    Secreted reporter molecules offer a means to evaluate biological processes in real time without the need to sacrifice samples at pre-determined endpoints. Here we have adapted the secreted bioluminescent reporter gene, Metridia luciferase, for use in a real-time viability assay for mammalian cells. The coding region of the marine copepod gene has been codon optimized for expression in human cells (hMLuc) and placed under the control of the human β-actin promoter and enhancer. Metridia luciferase activity of stably transfected cell models corresponded linearly with cell number over a 4-log dynamic range, detecting as few as 40 cells. When compared to standard endpoint viability assays, which measure the mitochondrial dehydrogenase reduction of tetrazolium salts, the hMLuc viability assay had a broader linear range of detection, was applicable to large tissue culture vessels, and allowed the same sample to be repeatedly measured over several days. Additional studies confirmed that MLuc activity was inhibited by serum, but demonstrated that assay activity remained linear and was measurable in the serum of mice bearing subcutaneous hMLuc-expressing tumors. In summary, these comparative studies demonstrate the value of humanized Metridia luciferase as an inexpensive and non-invasive method for analyzing viable cell number, growth, tumor volume, and therapeutic response in real time
    • …
    corecore