255 research outputs found

    Preferential inhibition of phorbol ester-induced hydrolysis of phosphatidylethanolamine by N-acetylsphingosine in NIH 3T3 fibroblasts

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    AbstractIt has been reported that in rat fibroblasts cell-permeable ceramide analogs inhibit agonist-induced phospholipase D (PLD)-mediated hydrolysis of phosphatidylcholine (PtdCho). Here we demonstrate that relatively short (30 min) treatments of NIH 3T3 fibroblasts with 15–60 μM concentrations of N-acetylsphingosine result in preferential, although not exclusive, inhibition of phorbol 12-myristate 13-acetate-induced PLD-mediated hydrolysis of phosphatidylethanolamine (PtdEtn). The results suggest that in different cell types the PtdEtn- and PtdCho-hydrolyzing PLD activities are differentially sensitive to the inhibitory effect of ceramide

    Cooperative interactions of protein kinase C and cAMP-dependent protein kinase systems in human promyelocytic leukemia HL60 cells

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    AbstractInteractions of protein kinase C (PKC) and cAMP-dependent protein kinase (PKA) systems were investigated in HL60 cells. It was found that the differentiating effects of 12-O-tetradecanoylphorbol-13-acetate (TPA) were potentiated by dibutyryl cAMP (dbcAMP) or prostaglandin E2 (PGE2). In addition, dbcAMP or PGE2 inhibited TPA-induced binding of PKC to plasma membrane, leading to decreased protein phosphorylation, and promoted subsequent redistribution of enzyme to the nuclear membrane region. The findings are consistent with the hypothesis that PKC and PKA systems regulate cooperatively the phenotypical differentiation of leukemic cells

    Implication of two new paradigms for futures studies

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    The paper considers the emergence of two recent perspectives in futures work. One is evolutionary futures studies. The other is critical futures studies. After describing aspects of each, the paper considers them as alternative rival paradigms in relation to criteria that include: the role of the human being as a subject, the role of interpretation and differences in methodological premises. It concludes that both have contributed to the development of futures methods but that a number of theoretical and methodological problems still remain unsolved

    The Footprint Database and Web Services of the Herschel Space Observatory

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    Data from the Herschel Space Observatory is freely available to the public but no uniformly processed catalogue of the observations has been published so far. To date, the Herschel Science Archive does not contain the exact sky coverage (footprint) of individual observations and supports search for measurements based on bounding circles only. Drawing on previous experience in implementing footprint databases, we built the Herschel Footprint Database and Web Services for the Herschel Space Observatory to provide efficient search capabilities for typical astronomical queries. The database was designed with the following main goals in mind: (a) provide a unified data model for meta-data of all instruments and observational modes, (b) quickly find observations covering a selected object and its neighbourhood, (c) quickly find every observation in a larger area of the sky, (d) allow for finding solar system objects crossing observation fields. As a first step, we developed a unified data model of observations of all three Herschel instruments for all pointing and instrument modes. Then, using telescope pointing information and observational meta-data, we compiled a database of footprints. As opposed to methods using pixellation of the sphere, we represent sky coverage in an exact geometric form allowing for precise area calculations. For easier handling of Herschel observation footprints with rather complex shapes, two algorithms were implemented to reduce the outline. Furthermore, a new visualisation tool to plot footprints with various spherical projections was developed. Indexing of the footprints using Hierarchical Triangular Mesh makes it possible to quickly find observations based on sky coverage, time and meta-data. The database is accessible via a web site (http://herschel.vo.elte.hu) and also as a set of REST web service functions.Comment: Accepted for publication in Experimental Astronom

    Immunocytochemical localization of protein kinase C in resting and activated human neutrophils

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    AbstractAn immunocytochemical method was used to determine possible changes in the subcellular distribution of protein kinase C (PKC) in human neutrophils in response to opsonized latex beads and zymosan. While in resting cells most of the PKC immunoreactivity was localized in the cytoplasm, a redistribution of PKC to the plasma and phagosomal membranes was observed in cells treated with latex beads or zymosan for 5–20 min, suggesting a participation of PKC in endocytosis

    Modelling financial sustainability of clusters: The case of Hungary

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    In Hungary, like in other post-socialist countries, clustering started only around the turn of the millennium. However, the mostly top-down organised clusters seemed not to be viable because the basic requirements of long-term operation, such as financial support and sufficient number of members, were not fulfilled. Thus, the main aim of this paper is to establish such a cluster-model which is applicable for the examination of clusters’ opportunity to be self-supporting under different circumstances. By determining the criteria of the long-term financial sustainability of clusters, the model and its simulations can considerably support the work of cluster managers and the competitiveness of clusters

    Swine influenza viruses isolated in 1983, 2002 and 2009 in Sweden exemplify different lineages

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    Swine influenza virus isolates originating from outbreaks in Sweden from 1983, 2002 and 2009 were subjected to nucleotide sequencing and phylogenetic analysis. The aim of the studies was to obtain an overview on their potential relatedness as well as to provide data for broader scale studies on swine influenza epidemiology. Nonetheless, analyzing archive isolates is justified by the efforts directed to the comprehension of the appearance of pandemic H1N1 influenza virus. Interestingly, this study illustrates the evolution of swine influenza viruses in Europe, because the earliest isolate belonged to 'classical' swine H1N1, the subsequent ones to Eurasian 'avian-like' swine H1N1 and reassortant 'avian-like' swine H1N2 lineages, respectively. The latter two showed close genetic relatedness regarding their PB2, HA, NP, and NS genes, suggesting common ancestry. The study substantiates the importance of molecular surveillance for swine influenza viruses

    Communicating "cure" to pediatric oncology patients: A mixed-methods study

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    Abstract Background Uncertainty about cure puts childhood cancer survivors at risk of mental distress. We asked survivors if they had been told they had been cured and investigated associated factors. Procedure We used nationwide registry data and a questionnaire survey for ≥five-year survivors of childhood cancer (n = 301), followed by online focus groups with a purposive sample of Swiss pediatric oncologists (n = 17). Discussions were coded by investigators using thematic analysis. Results Overall, 235 among 301 survivors (78%; 95% confidence interval, 73%?83%) reported having been told they were cured. The proportion was 89% (81%?97%) among lymphoma and 84% (77%?91%) among leukemia survivors, but only 49% (33%?65%) among central nervous system tumor survivors. Pediatric oncologists acknowledged that telling survivors they are cured may reassure them that their cancer lies behind them. However, many refrained from telling all patients. Reasons included the possibility of late effects (cure disrupted by a continued need for follow-up care) or late relapse (uncertainty of biological cure), case-by-case strategies (use of ?cure? according to individual factors), and reluctance (substitution of noncommittal terms for ?cure?; waiting for the patient to raise the topic). Conclusions Not all physicians tell survivors they have been cured; their choices depend on the cancer type and risk of late effects

    The Combination of Single-Cell and Next-Generation Sequencing Can Reveal Mosaicism for BRCA2 Mutations and the Fine Molecular Details of Tumorigenesis

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    Simple Summary Germline and somatic BRCA1/2 mutations may define therapeutic targets and refine cancer treatment options. However, routine BRCA diagnostic approaches cannot reveal the exact time and origin of BRCA1/2 mutation formation, and thus, the fine details of their contribution to tumor progression remain less clear. We established a diagnostic pipeline using high-resolution microscopy and laser microcapture microscopy to test for BRCA1/2 mutations in tumors at the single-cell level, followed by deep next-generation sequencing of various tissues from the patient. To demonstrate the power of our approach, here we present a detailed analysis of an ovarian cancer patient, in which we describe constitutional somatic mosaicism of a BRCA2 mutation. Characterization of the mosaic mutation at the single-cell level contributes to a better understanding of BRCA mutation formation and supports the concept that the combination of single-cell and next-generation sequencing methods is advantageous over traditional mutational analysis methods. Germline mutations in the BRCA1 and BRCA2 genes are responsible for hereditary breast and ovarian cancer syndrome. Germline and somatic BRCA1/2 mutations may define therapeutic targets and refine cancer treatment options. However, routine BRCA diagnostic approaches cannot reveal the exact time and origin of BRCA1/2 mutation formation, and thus, the fine details of their contribution to tumor progression remain less clear. Here, we establish a diagnostic pipeline using high-resolution microscopy and laser microcapture microscopy to test for BRCA1/2 mutations in the tumor at the single-cell level, followed by deep next-generation sequencing of various tissues from the patient. To demonstrate the power of our approach, here, we describe a detailed single-cell-level analysis of an ovarian cancer patient we found to exhibit constitutional somatic mosaicism of a pathogenic BRCA2 mutation. Employing next-generation sequencing, BRCA2 c.7795G>T, p.(Glu2599Ter) was detected in 78% of reads in DNA extracted from ovarian cancer tissue and 25% of reads in DNA derived from peripheral blood, which differs significantly from the expected 50% of a hereditary mutation. The BRCA2 mutation was subsequently observed at 17-20% levels in the normal ovarian and buccal tissue of the patient. Together, our findings suggest that this mutation occurred early in embryonic development. Characterization of the mosaic mutation at the single-cell level contributes to a better understanding of BRCA mutation formation and supports the concept that the combination of single-cell and next-generation sequencing methods is advantageous over traditional mutational analysis methods. This study is the first to characterize constitutional mosaicism down to the single-cell level, and it demonstrates that BRCA2 mosaicism occurring early during embryogenesis can drive tumorigenesis in ovarian cancer.Peer reviewe
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