223 research outputs found

    Bivariant Hopf cyclic cohomology

    No full text

    Determination of Quality Indicators for a Teacher Training System

    Get PDF
    ABSTRACT With respect to the increasing local and global demands for qualified teachers throughout the world, there are expected from teacher training centers to establish quality indicators and standards, to ensure the quality of future teachers. Essentially the effective teachers are developed in institutions where professional programs are consistent with state/national/global standards and there are connections across curriculum, instruction, and field/clinical experiences; inquiry, reflection, research, and assessment result in continuing professional growth and development; commitment to professional and school/community engagement is modeled and supported by everyone participating in the program; individual differences and diversity are valued; and emphasis is placed upon lifelong learning and growth in professional development. The purpose of this article was factoring and modeling of quality indicators for a teacher training system in Iran. The research type was Mixed method. The populations units were the elite's teacher training system of Iran. The sample was selected by purposive sampling. Finally the result factored 18 quality indicators, definition to Teacher Training System

    Curvature in Noncommutative Geometry

    Full text link
    Our understanding of the notion of curvature in a noncommutative setting has progressed substantially in the past ten years. This new episode in noncommutative geometry started when a Gauss-Bonnet theorem was proved by Connes and Tretkoff for a curved noncommutative two torus. Ideas from spectral geometry and heat kernel asymptotic expansions suggest a general way of defining local curvature invariants for noncommutative Riemannian type spaces where the metric structure is encoded by a Dirac type operator. To carry explicit computations however one needs quite intriguing new ideas. We give an account of the most recent developments on the notion of curvature in noncommutative geometry in this paper.Comment: 76 pages, 8 figures, final version, one section on open problems added, and references expanded. Appears in "Advances in Noncommutative Geometry - on the occasion of Alain Connes' 70th birthday

    Imaging in situ breast carcinoma (with or without an invasive component) with technetium-99m pentavalent dimercaptosuccinic acid and technetium-99m 2-methoxy isobutyl isonitrile scintimammography

    Get PDF
    INTRODUCTION: The aim of the study was to retrospectively define specific features of the technetium-99m pentavalent dimercaptosuccinic acid ((99m)Tc-(V)DMSA) and technetium-99m 2-methoxy isobutyl isonitrile ((99m)Tc-Sestamibi [(99m)Tc-MIBI]) distribution in ductal breast carcinoma in situ and lobular breast carcinoma in situ (DCIS/LCIS), in relation to mammographic, histological and immunohistochemical parameters. MATERIALS AND METHODS: One hundred and two patients with suspicious palpation or mammographic findings were submitted preoperatively to scintimammography (a total of 72 patients with (99m)Tc-(V)DMSA and a total of 75 patients with (99m)Tc-Sestamibi, 45 patients receiving both radiotracers). Images were acquired at 10 min and 60 min, and were evaluated for a pattern of diffuse radiotracer accumulation. The tumor-to-background ratios were correlated (T-pair test) with mammographic, histological and immunohistochemical characteristics. RESULTS: Histology confirmed malignancy in 46/102 patients: 20/46 patients had DCIS/LCIS, with or without coexistent invasive lesions, and 26/46 patients had isolated invasive carcinomas. Diffuse (99m)Tc-(V)DMSA accumulation was noticed in 18/19 cases and (99m)Tc-Sestamibi in 6/13 DCIS/LCIS cases. Epithelial hyperplasia demonstrated a similar accumulation pattern. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value for each tracer were calculated. Solely for (99m)Tc-(V)DMSA, the tumor-to-background ratio was significantly higher at 60 min than at 10 min and the diffuse uptake was significantly associated with suspicious microcalcifications, with the cell proliferation index ≥ 40% and with c-erbB-2 ≥ 10%. CONCLUSION: (99m)Tc-(V)DMSA showed high sensitivity and (99m)Tc-Sestamibi showed high specificity in detecting in situ breast carcinoma ((99m)Tc-(V)DMSA especially in cases with increased cell proliferation), and these radiotracers could provide clinicians with preoperative information not always obtainable by mammography

    On the algebraic index for riemannian \'etale groupoids

    Get PDF
    In this paper we construct an explicit quasi-isomorphism to study the cyclic cohomology of a deformation quantization over a riemannian \'etale groupoid. Such a quasi-isomorphism allows us to propose a general algebraic index problem for riemannian \'etale groupoids. We discuss solutions to that index problem when the groupoid is proper or defined by a constant Dirac structure on a 3-dim torus.Comment: 19 page

    Differential and holomorphic differential operators on noncommutative algebras

    Get PDF
    Abstract This paper deals with sheaves of differential operators on noncommutative algebras, in a manner related to the classical theory of D-modules. The sheaves are defined by quotienting the tensor algebra of vector fields (suitably deformed by a covariant derivative). As an example we can obtain enveloping algebra like relations for Hopf algebras with differential structures which are not bicovariant. Symbols of differential operators are defined, but not studied. These sheaves are shown to be in the center of a category of bimodules with flat bimodule covariant derivatives. Also holomorphic differential operators are considered

    Continued 26S proteasome dysfunction in mouse brain cortical neurons impairs autophagy and the Keap1-Nrf2 oxidative defence pathway

    Get PDF
    The ubiquitin–proteasome system (UPS) and macroautophagy (autophagy) are central to normal proteostasis and interdependent in that autophagy is known to compensate for the UPS to alleviate ensuing proteotoxic stress that impairs cell function. UPS and autophagy dysfunctions are believed to have a major role in the pathomechanisms of neurodegenerative disease. Here we show that continued 26S proteasome dysfunction in mouse brain cortical neurons causes paranuclear accumulation of fragmented dysfunctional mitochondria, associated with earlier recruitment of Parkin and lysine 48-linked ubiquitination of mitochondrial outer membrane (MOM) proteins, including Mitofusin-2. Early events also include phosphorylation of p62/SQSTM1 (p62) and increased optineurin, as well as autophagosomal LC3B and removal of some mitochondria, supporting the induction of selective autophagy. Inhibition of the degradation of ubiquitinated MOM proteins with continued 26S proteasome dysfunction at later stages may impede efficient mitophagy. However, continued 26S proteasome dysfunction also decreases the levels of essential autophagy proteins ATG9 and LC3B, which is characterised by decreases in their gene expression, ultimately leading to impaired autophagy. Intriguingly, serine 351 phosphorylation of p62 did not enhance its binding to Keap1 or stabilise the nuclear factor erythroid 2-related factor 2 (Nrf2) transcription factor in this neuronal context. Nrf2 protein levels were markedly decreased despite transcriptional activation of the Nrf2 gene. Our study reveals novel insights into the interplay between the UPS and autophagy in neurons and is imperative to understanding neurodegenerative disease where long-term proteasome inhibition has been implicated

    Novel gold nanoparticles coated with somatostatin as a potential delivery system for targeting somatostatin receptors

    Get PDF
    Targeting of G-protein coupled receptors (GPCRs) like somatostatin-14 (SST-14) could have a potential interest in delivery of anti-cancer agents to tumor cells. Attachment of SST to different nano-carriers e.g., polymeric nanoparticles is limited due to the difficulty of interaction between SST itself and those nano-carriers. Furthermore, the instability problems associated with the final formulation. Attaching of SST to gold nanoparticles (AuNPs) using the positive and negative charge of SST and citrate-AuNPs could be considered a new technique to get stable non-aggregated AuNPs coated with SST. Different analyses techniques have been performed to proof the principle of coating between AuNPs and SST. Furthermore, cellular uptake study on HCC-1809 cell lines has been investigated to show the ability of AuNPs coated SST to enter the cells via SST receptors. Dynamic light scattering (DLS) indicated a successful coating of SST on the MUA-AuNPs surface. Furthermore, all the performed analysis including DLS, SDS-PAGE and UV-VIS absorption spectra indicated a successful coating of AuNPs with SST. Cellular uptake study on HCC-1806 cell lines showed that the number of AuNPs-SST per cell is significantly higher compared to citrate-AuNPs when quantified using inductively coupled plasma spectroscopy. Moreover, the binding of AuNPs-SST to cells can be suppressed by addition of antagonist, indicating that the binding of AuNPs-SST to cells is due to receptor-specific binding. In conclusion, AuNPs could be attached to SST via adsorption to get stable AuNPs coated SST. This new formulation has a potential to target SST receptors localized in many normal and tumor cells

    A synergistic antiproliferation effect of curcumin and docosahexaenoic acid in SK-BR-3 breast cancer cells: unique signaling not explained by the effects of either compound alone

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Breast cancer is a collection of diseases in which molecular phenotypes can act as both indicators and mediators of therapeutic strategy. Therefore, candidate therapeutics must be assessed in the context of multiple cell lines with known molecular phenotypes. Docosahexaenoic acid (DHA) and curcumin (CCM) are dietary compounds known to antagonize breast cancer cell proliferation. We report that these compounds in combination exert a variable antiproliferative effect across multiple breast cell lines, which is synergistic in SK-BR-3 cells and triggers cell signaling events not predicted by the activity of either compound alone.</p> <p>Methods</p> <p>Dose response curves for CCM and DHA were generated for five breast cell lines. Effects of the DHA+ CCM combination on cell proliferation were evaluated using varying concentrations, at a fixed ratio, of CCM and DHA based on their individual ED<sub>50</sub>. Detection of synergy was performed using nonlinear regression of a sigmoid dose response model and Combination Index approaches. Cell molecular network responses were investigated through whole genome microarray analysis of transcript level changes. Gene expression results were validated by RT-PCR, and western blot analysis was performed for potential signaling mediators. Cellular curcumin uptake, with and without DHA, was analyzed via flow cytometry and HPLC.</p> <p>Results</p> <p>CCM+DHA had an antiproliferative effect in SK-BR-3, MDA-MB-231, MDA-MB-361, MCF7 and MCF10AT cells. The effect was synergistic for SK-BR-3 (ER<sup>- </sup>PR<sup>- </sup>Her2<sup>+</sup>) relative to the two compounds individually. A whole genome microarray approach was used to investigate changes in gene expression for the synergistic effects of CCM+DHA in SK-BR-3 cells lines. CCM+DHA triggered transcript-level responses, in disease-relevant functional categories, that were largely non-overlapping with changes caused by CCM or DHA individually. Genes involved in cell cycle arrest, apoptosis, inhibition of metastasis, and cell adhesion were upregulated, whereas genes involved in cancer development and progression, metastasis, and cell cycle progression were downregulated. Cellular pools of PPARγ and phospho-p53 were increased by CCM+DHA relative to either compound alone. DHA enhanced cellular uptake of CCM in SK-BR-3 cells without significantly enhancing CCM uptake in other cell lines.</p> <p>Conclusions</p> <p>The combination of DHA and CCM is potentially a dietary supplemental treatment for some breast cancers, likely dependent upon molecular phenotype. DHA enhancement of cellular curcumin uptake is one potential mechanism for observed synergy in SK-BR-3 cells; however, transcriptomic data show that the antiproliferation synergy accompanies many signaling events unique to the combined presence of the two compounds.</p

    The utility of pathway selective estrogen receptor ligands that inhibit nuclear factor-κB transcriptional activity in models of rheumatoid arthritis

    Get PDF
    Rheumatoid arthritis (RA) is a chronic inflammatory disease that produces synovial proliferation and joint erosions. The pathologic lesions of RA are driven through the production of inflammatory mediators in the synovium mediated, in part, by the transcription factor NF-κB. We have identified a non-steroidal estrogen receptor ligand, WAY-169916, that selectively inhibits NF-κB transcriptional activity but is devoid of conventional estrogenic activity. The activity of WAY-169916 was monitored in two models of arthritis, the HLA-B27 transgenic rat and the Lewis rat adjuvant-induced model, after daily oral administration. In both models, a near complete reversal in hindpaw scores was observed as well as marked improvements in the histological scores. In the Lewis rat adjuvant model, WAY-169916 markedly suppresses the adjuvant induction of three serum acute phase proteins: haptoglobin, α1-acid glycoprotein (α1-AGP), and C-reactive protein (CRP). Gene expression experiments also demonstrate a global suppression of adjuvant-induced gene expression in the spleen, liver, and popliteal lymph nodes. Finally, WAY-169916 was effective in suppressing tumor necrosis factor-α-mediated inflammatory gene expression in fibroblast-like synoviocytes isolated from patients with RA. Together, these data suggest the utility of WAY-169916, and other compounds in its class, in treating RA through global suppression of inflammation via selective blockade of NF-κB transcriptional activity
    corecore