2,724 research outputs found

    Curcumin Enhances Bortezomib Treatment of Myeloma by Inhibiting Heat Shock Protein 90 Expression

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    Purpose: To investigate whether curcumin augments bortezomib-induced apoptosis in myeloma cells (MM1.R line), and to explore the molecular mechanism with regard to heat shock protein 90 (HSP90) expression.Methods: MTT cell viability assay was used to assess growth inhibition of MM1.R cells at different concentrations of curcumin alone and also combined with 0.01 mM bortezomib. Annexin V and propidium iodide (PI) labeling were used to detect apoptosis. Caspase 3, caspase 9, NF-ÎșB, and HSP 90 protein expression were measured by Western blotting.Results: Curcumin alone inhibited MM1.R cell growth and increased apoptosis in a concentration dependent manner. When curcumin was combined with low concentration (0.01 mM) bortezomib, both effectsviability inhibition and apoptosis induction increased (p < 0.05), whereas bortezomib alone had no effect (p > 0.05). Western blotting revealed that for curcumin and combined treatments, expression of the apoptotic markers, caspase 3 and caspase 9, increased while expression of NF-ÎșB and HSP 90 decreased (p < 0.05). Again, low concentration bortezomib alone had no effect, whereas the combined treatment showed the largest effect, thus suggesting that the actions of curcumin and bortezomib are synergistic.Conclusion: Curcumin increased MM1.R cell sensitivity to bortezomib, which may be due to suppression of NF-ÎșB and HSP90 activity.Keywords: Curcumin, Bortezomib, Myeloma cells, Cell growth, Apoptosis, Heat shock protein 9

    Multiwavelength Observations of Pulsar Wind Nebulae

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    The extended nebulae formed as pulsar winds expand into their surroundings provide information about the composition of the winds, the injection history from the host pulsar, and the material into which the nebulae are expanding. Observations from across the electromagnetic spectrum provide constraints on the evolution of the nebulae, the density and composition of the surrounding ejecta, the geometry of the central engines, and the long-term fate of the energetic particles produced in these systems. Such observations reveal the presence of jets and wind termination shocks, time-varying compact emission structures, shocked supernova ejecta, and newly formed dust. Here I provide a broad overview of the structure of pulsar wind nebulae, with specific examples from observations extending from the radio band to very-high-energy gamma-rays that demonstrate our ability to constrain the history and ultimate fate of the energy released in the spin-down of young pulsars.Comment: 20 pages, 11 figures. Invited review to appear in Proc. of the inaugural ICREA Workshop on "The High-Energy Emission from Pulsars and their Systems" (2010), eds. N. Rea and D. Torres, (Springer Astrophysics and Space Science series

    Use of domesticated pigs by Mesolithic hunter-gatherers in northwestern Europe

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    Acknowledgements We thank the Archaeological State Museum Schleswig-Holstein, the Archaeological State Offices of Brandenburg, Lower Saxony and Saxony and the following individuals who provided sample material: Betty Arndt, Jo¹rg Ewersen, Frederick Feulner, Susanne Hanik, Ru¹diger Krause, Jochen Reinhard, Uwe Reuter, Karl-Heinz Ro¹hrig, Maguerita Scha¹fer, Jo¹rg Schibler, Reinhold Schoon, Regina Smolnik, Thomas Terberger and Ingrid Ulbricht. We are grateful to Ulrich Schmo¹lcke, Michael Forster, Peter Forster and Aikaterini Glykou for their support and comments on the manuscript. We also thank many institutions and individuals that provided sample material and access to collections, especially the curators of the Museum fu¹r Naturkunde, Berlin; Muse®um National d0 Histoire Naturelle, Paris; Smithsonian Institution, National Museum of Natural History, Washington D.C.; Zoologische Staatssammlung, Mu¹nchen; Museum fu¹r Haustierkunde, Halle; the American Museum of Natural History, New-York. This work was funded by the Graduate School ‘Human Development in Landscapes’ at Kiel University (CAU) and supported by NERC project Grant NE/F003382/1. Radiocarbon dating was carried out at the Leibniz Laboratory, CAU. This work is licensed under a Creative Commons AttributionNonCommercial-NoDerivs 3.0 Unported License.Peer reviewedPublisher PD

    Steps toward Determination of the Size and Structure of the Broad-Line Region in Active Galactic Nuclei. XII. Ground-Based Monitoring of 3C 390.3

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    Results of a ground-based optical monitoring campaign on 3C 390.3 in 1994-95 are presented. The broad-band fluxes (B, V, R, and I), the spectrophotometric optical continuum flux F(5177) and the integrated emission-line fluxes of Ha, Hb, Hg, HeI, and HeII all show a nearly monotonic increase with episodes of milder short-term variations superposed. The amplitude of the continuum variations increases with decreasing wavelength (4400-9000 A). The optical continuum variations follow the variations in the ultraviolet and X-ray with time delays, measured from the centroids of the cross- correlation functions, typically around 5 days, but with uncertainties also typically around 5 days; zero time delay between the high-energy and low-energy continuum variations cannot be ruled out. The strong optical emission lines Ha, Hb, Hg, and HeI respond to the high-energy continuum variations with time delays typically about 20 days, with uncertainties of about 8 days. There is some evidence that HeII responds somewhat more rapidly, with a time delay of around 10 days, but again, the uncertainties are quite large (~8 days). The mean and rms spectra of the Ha and Hb line profiles provide indications for the existence of at least three distinct components located at +-4000 and 0 km/s relative to the line peak. The emission-line profile variations are largest near line center.Comment: 42 pages (Latex), 13 figures, 14 table

    Biphasic synovial sarcoma in the cervical spine: Case report

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    Synovial sarcoma is a rare malignant neoplasm of soft tissue that typically arising near large joints of the upper and lower extremities in young adult males. Only 3% of these neoplasms have been found to arise in the head and neck region. To our knowledge, there are limited reports in the literature of this neoplasm in the cervical spine

    The Escherichia coli transcriptome mostly consists of independently regulated modules

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    Underlying cellular responses is a transcriptional regulatory network (TRN) that modulates gene expression. A useful description of the TRN would decompose the transcriptome into targeted effects of individual transcriptional regulators. Here, we apply unsupervised machine learning to a diverse compendium of over 250 high-quality Escherichia coli RNA-seq datasets to identify 92 statistically independent signals that modulate the expression of specific gene sets. We show that 61 of these transcriptomic signals represent the effects of currently characterized transcriptional regulators. Condition-specific activation of signals is validated by exposure of E. coli to new environmental conditions. The resulting decomposition of the transcriptome provides: a mechanistic, systems-level, network-based explanation of responses to environmental and genetic perturbations; a guide to gene and regulator function discovery; and a basis for characterizing transcriptomic differences in multiple strains. Taken together, our results show that signal summation describes the composition of a model prokaryotic transcriptome

    Investigation of the structural requirements for N-methyl-D-aspartate receptor positive and negative allosteric modulators based on 2-naphthoic acid.

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    The N-methyl-D-aspartate receptor (NMDAR), a ligand-gated ion channel activated by L-glutamate and glycine, plays a major role in the synaptic plasticity underlying learning and memory. NMDARs are involved in neurodegenerative disorders such as Alzheimer's and Parkinson's disease and NMDAR hypofunction is implicated in schizophrenia. Herein we describe structure-activity relationship (SAR) studies on 2-naphthoic acid derivatives to investigate structural requirements for positive and negative allosteric modulation of NMDARs. These studies identified compounds such as UBP684 (14b), which act as pan potentiators by enhancing NMDAR currents in diheteromeric NMDAR tetramers containing GluN1 and GluN2A-D subunits. 14b and derivatives thereof are useful tools to study synaptic function and have potential as leads for the development of drugs to treat schizophrenia and disorders that lead to a loss of cognitive function. In addition, SAR studies have identified a series of styryl substituted compounds with partial NAM activity and a preference for inhibition of GluN2D versus the other GluN2 subunits. In particular, the 3-and 2-nitrostyryl derivatives UBP783 (79i) and UBP792 (79h) had IC50s of 1.4â€ŻÎŒM and 2.9â€ŻÎŒM, respectively, for inhibition of GluN2D but showed only 70-80% maximal inhibition. GluN2D has been shown to play a role in excessive pain transmission due to nerve injury and potentially in neurodegenerative disorders. Partial GluN2D inhibitors may be leads for the development of drugs to treat these disorders without the adverse effects observed with full NMDAR antagonists.National Institute of Mental Health of the National Institutes of Health under Award Number R01MH060252, the Medical Research Council, United Kingdom (Grants G0601509, G0601812) and the BBSRC (grant BB/L001977/1)

    Consumer perceptions of co-branding alliances: Organizational dissimilarity signals and brand fit

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    This study explores how consumers evaluate co-branding alliances between dissimilar partner firms. Customers are well aware that different firms are behind a co-branded product and observe the partner firms’ characteristics. Drawing on signaling theory, we assert that consumers use organizational characteristics as signals in their assessment of brand fit and for their purchasing decisions. Some organizational signals are beyond the control of the co-branding partners or at least they cannot alter them on short notice. We use a quasi-experimental design and test how co-branding partner dissimilarity affects brand fit perception. The results show that co-branding partner dissimilarity in terms of firm size, industry scope, and country-of-origin image negatively affects brand fit perception. Firm age dissimilarity does not exert significant influence. Because brand fit generally fosters a benevolent consumer attitude towards a co-branding alliance, the findings suggest that high partner dissimilarity may reduce overall co-branding alliance performance
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