469 research outputs found

    Early Switch in Glial Protein and Fibronectin Markers on Cells during the Culture of Human Gliomas

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75201/1/j.1749-6632.1984.tb13851.x.pd

    Arcuate Nucleus Transcriptome Profiling Identifies Ankyrin Repeat and Suppressor of Cytokine Signalling Box-Containing Protein 4 as a Gene Regulated by Fasting in Central Nervous System Feeding Circuits

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    The arcuate nucleus of the hypothalamus is a primary site for sensing blood borne nutrients and hormonal messengers that reflect caloric status. To identify novel energy homeostatic genes, we examined RNA extracts from the microdissected arcuate nucleus of fed and 48-h fasted rats using oligonucleotide microarrays. The relative abundance of 118 mRNA transcripts was increased and 203 mRNA transcripts was decreased during fasting. One of the down-regulated mRNAs was ankyrin-repeat and suppressor of cytokine signalling box-containing protein 4 (Asb-4). The predicted structure of Asb-4 protein suggested that it might encode an intracellular regulatory protein, and therefore its mRNA expression was investigated further. Reverse transcription quantitative polymerase chain reaction was used to validate down-regulation of Asb-4 mRNA in the arcuate nucleus of the fasted Sprague-Dawley rat (relative expression of Asb-4 mRNA: fed = 4.66 ± 0.26; fasted = 3.96 ± 0.23; n = 4, P < 0.01). Down-regulation was also demonstrated in the obese fa/fa Zucker rat, another model of energy disequilibrium (relative expression of Asb-4 mRNA: lean Zucker = 3.91 ± 0.32; fa/fa  = 2.93 ± 0.26; n = 5, P < 0.001). In situ hybridisation shows that Asb-4 mRNA is expressed in brain areas linked to energy homeostasis, including the arcuate nucleus, paraventricular nucleus, dorsomedial nucleus, lateral hypothalamus and posterodorsal medial amygdaloid area. Double in situ hybridisation revealed that Asb-4 mRNA colocalises with key energy homeostatic neurones. In the fed state, Asb-4 mRNA is expressed by 95.6% of pro-opiomelanocortin (POMC) neurones and 46.4% of neuropeptide Y (NPY) neurones. By contrast, in the fasted state, the percentage of POMC neurones expressing Asb-4 mRNA drops to 73.2% (P  <  0.001). Moreover, the density of Asb-4 mRNA per fasted POMC neurone is markedly decreased. Conversely, expression of Asb-4 mRNA by NPY neurones in the fasted state is modestly increased to 52.7% (P  <  0.05). Based on its differential expression, neuroanatomical distribution and colocalisation, we hypothesise that Asb-4 is a gene involved in energy homeostasis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73490/1/j.1365-2826.2005.01317.x.pd

    DNA content and marker expression in human glioma explants

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    Immunohistochemical studies of astrocytoma tissue have predominately shown fibronectin (FN) positivity restricted to vessels and glial fibrillary acidic protein (GFAP) positivity in the parenchyma. Cultured glioma cell lines, however, express both FN and GFAP. We measured the DNA content of explants of gliomas to determine if the ploidy of the FN-positive and GFAP-positive cells differed. Thirty-three explants from four high grade gliomas were cultured on slides. FN and GFAP markers were determined by double immunofluorescence. The slides were stained by the Feulgen method, the explants relocated and the DNA content measured by microdensitometry using the CAS-100 instrument. Human leukocytes applied to the slides were used as a diploid standard. Eleven GFAP-positive explants were hyperdiploid and one hypodiploid. Five FN-positive explants were diploid, three hypodiploid and ten hyperdiploid. One FN-positive explant was biclonal with aneuploid subpopulations. Two hyperdiploid explants, each of which had monoclonal histogram patterns, expressed both FN and GFAP. We conclude that most FN-positive cells, in addition to GFAP-positive cells, from cultured gliomas represent neoplastic cells. These may be present in the tumor in low numbers or may result from marker switching in culture.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47230/1/401_2004_Article_BF00687213.pd

    Products of cultured neuroglial cells: II. The production of fibronectin by C6 glioma cells

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    The possibility of fibronectin production by C6 glioma cells was examined with assays which require protein synthesis. Proteins produced by C6 cells using radiolabeled amino acid precursors were tested for affinity to collagen by binding to immobilized gelatin. The predominant collagen binding protein made by C6 coelectrophoresed with fibronectin synthesized by control fibroblasts and with the larger of the two proteins in unlabeled fibronectin when applied to polyacrylamide gels with sodium dodecyl sulfate (SDS). In addition, C6 produced a larger collagen binding protein of approximately 270,000 molecular weight. Solubilities in urea solutions of the collagen-binding proteins made by C6 cells and fibroblasts were similar. Immunofluorescence showed fibronectin associated with the C6 cell monolayer, but less abundant than the fibronectin associated with fibroblasts. Results provide evidence for the production of fibronectin by the C6 glioma cell line.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45400/1/11064_2004_Article_BF00964399.pd

    Products of cells from gliomas: IX. Evidence that two fundamentally different mechanisms change extracellular matrix expression by gliomas

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    Four human astrocytic gliomas of high grade of malignancy were each evaluated in tissue and in vitro for percentages of cells expressing glial fibrillary acidic protein (GFAP), collagen type IV, laminin and fibronectin assessed by immunofluorescence with counterstaining of nuclear DNA. Percentages of cells with reticulin and cells binding fluorescein-labeled Ulex europaeus agglutinin were also assessed. In tissue, each extracellular matrix (ECM) component was associated with cells in the walls of abnormal proliferations of glioma vessels, and all four tumors had the same staining pattern. Two strikingly different patterns of conversion of gene product expression emerged during in vitro cultivation. (1). In the most common pattern, percentages of all six markers consistently shifted toward the exact phenotype of mesenchymal cells in abnormal vascular proliferations: increased reticulin, collagen type IV, laminin and fibronectin; markedly decreased glial marker GFAP and absent endothelial marker Ulex europaeus agglutinin. The simplest explanation of this constellation of changes coordinated toward expression of vascular ECM markers is that primary glioma cell cultures are overgrown by mesenchymal cells from the abnormal vascular proliferations of the original glioma. These cell cultures were tested for in situ hybridization (ISH) signals of chromosomes 7 and 10. Cells from one glioma had diploid signals. Cells from the other glioma had aneuploid signals indicating they were neoplastic; however, their signals reflected different numerical chromosomal aberrations than those common to neoplastic glia. (2). The second pattern was different. Cells with ISH chromosomal signals of neoplastic glia retained GFAP, and gained collagen type IV. Their laminin and fibronectin diminished, but persisted among a lower percentage of cells. Cloning and double immunofluorescence confirmed the presence of individual cells with glial and mesenchymal markers. A cell expressing GFAP in addition to either fibronectin, reticulin or collagen type IV is not a known constituent of glioblastoma tissue. This provides evidence of a second mechanism of conversion of gene expression in gliomas.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45382/1/11060_2005_Article_BF01052843.pd

    Neuronal diversity of the amygdala and the bed nucleus of the stria terminalis

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    The amygdala complex is a diverse group of more than 13 nuclei, segregated in five major groups: the basolateral (BLA), central (CeA), medial (MeA), cortical (CoA), and basomedial (BMA) amygdala nuclei. These nuclei can be distinguished depending on their cytoarchitectonic properties, connectivity, genetic, and molecular identity, and most importantly, on their functional role in animal behavior. The extended amygdala includes the CeA and the bed nucleus of the stria terminalis (BNST). Both CeA and the BNST share similar cellular organization, including common neuron types, reciprocal connectivity, and many overlapping downstream targets. In this section, we describe the advances of our knowledge on neuronal diversity in the amygdala complex and the BNST, based on recent functional studies, performed at genetic, molecular, physiological, and anatomical levels in rodent models, especially rats and mice. Molecular and connection property can be used separately, or in combinations, to define neuronal populations, leading to a multiplexed neuronal diversity-supporting different functional roles. © 2020 Elsevier B.V

    Brolle ny på jobbet : En studie om RPAs påverkan på digital arbetsmiljö

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    Den ökade datakraften och digitaliseringen av arbete har bidragit till möjligheten att automatisera processer. En metod för att automatisera processer är med Robotic Process Automation (RPA), vilket utför regelstyrda uppgifter baserat på detaljerade processbeskrivningar. Användningen av RPA blir allt vanligare inom den offentliga sektorn. Ett exempel på detta är Trafikverket som infört RPA för att automatisera processer med målet att frigöra tid för medarbetare. Denna studie har undersökt vad Trafikverkets införande och användning av RPA har inneburit för den digitala arbetsmiljön. Studien har undersökt detta genom att genomföra intervjuer med medarbetare som påverkats till följd av införandet och användning av RPA eller varit delaktig i införandet av RPA-lösningen. Studiens bidrag skapar en ökad förståelse för vad införandet och användandet av RPA har för konsekvenser på digital arbetsmiljö i organisationer i den offentliga sektorn genom att presentera tre konsekvenser. Studien visar att användningen av RPA kan resultera i en initial oro och en upplevd minskad anställningstrygghet bland medarbetarnas. Nya arbetsuppgifter kan uppstå till följd av införandet av RPA, dessa kan upplevas som monotona och irritationsmoment av medarbetarna. Slutligen kan det innebära att medarbetare får mer tid till varierande och kvalificerade arbetsuppgifter med möjlighet till kompetensutveckling. Detta resulterar i att medarbetarna uttrycker en ökad förändringsbenägenhet gentemot fortsatt automatisering med RPA
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