517 research outputs found
Atropselective syntheses of (-) and (+) rugulotrosin A utilizing point-to-axial chirality transfer
Chiral, dimeric natural products containing complex structures and interesting biological properties have inspired chemists and biologists for decades. A seven-step total synthesis of the axially chiral, dimeric tetrahydroxanthone natural product rugulotrosin A is described. The synthesis employs a one-pot Suzuki coupling/dimerization to generate the requisite 2,2'-biaryl linkage. Highly selective point-to-axial chirality transfer was achieved using palladium catalysis with achiral phosphine ligands. Single X-ray crystal diffraction data were obtained to confirm both the atropisomeric configuration and absolute stereochemistry of rugulotrosin A. Computational studies are described to rationalize the atropselectivity observed in the key dimerization step. Comparison of the crude fungal extract with synthetic rugulotrosin A and its atropisomer verified that nature generates a single atropisomer of the natural product.P50 GM067041 - NIGMS NIH HHS; R01 GM099920 - NIGMS NIH HHS; GM-067041 - NIGMS NIH HHS; GM-099920 - NIGMS NIH HH
In-play sports betting: a scoping study
Technology has changed the nature of gambling practices over the last decade and is continuing to do so. The online sports betting industry has become a rapidly growing sector of the global economy, with online sports betting contributing 37% of the annual online gambling market in Europe. There has been an integration of social and technological processes that has enabled the cultural saliency of contemporary online betting. One of the more newly introduced forms of online sports betting is in-play sports betting behaviour (the betting on events within a sporting event such as football and cricket). In-play sports betting features (such as 'cash out') are increasing in popularity amongst online gambling operators. A scoping study was carried out examining the evolution of this new form of gambling practice which included both a systematic literature review and the examination of 338 online gambling websites that offered sports betting. The present study identified a comprehensive list of what in-play betting features are currently being offered on online gambling websites as well as other information concerning in-play sports betting. A total of 16 academic papers and two 'grey literature' reports and were identified in the systematic review. Out of 338 online gambling websites that were visited, 26% of these offered at least on in-play betting feature. Results from the systematic review suggest that in-play sports betting has the potential to be more harmful than other ways of gambling because of the inherent structural characteristics
In-play sports betting: a scoping study
Technology has changed the nature of gambling practices over the last decade and is continuing to do so. The online sports betting industry has become a rapidly growing sector of the global economy, with online sports betting contributing 37% of the annual online gambling market in Europe. There has been an integration of social and technological processes that has enabled the cultural saliency of contemporary online betting. One of the more newly introduced forms of online sports betting is in-play sports betting behaviour (the betting on events within a sporting event such as football and cricket). In-play sports betting features (such as 'cash out') are increasing in popularity amongst online gambling operators. A scoping study was carried out examining the evolution of this new form of gambling practice which included both a systematic literature review and the examination of 338 online gambling websites that offered sports betting. The present study identified a comprehensive list of what in-play betting features are currently being offered on online gambling websites as well as other information concerning in-play sports betting. A total of 16 academic papers and two 'grey literature' reports and were identified in the systematic review. Out of 338 online gambling websites that were visited, 26% of these offered at least on in-play betting feature. Results from the systematic review suggest that in-play sports betting has the potential to be more harmful than other ways of gambling because of the inherent structural characteristics
Kinome rewiring reveals AURKA limits PI3K-pathway inhibitor efficacy in breast cancer.
Dysregulation of the PI3K-AKT-mTOR signaling network is a prominent feature of breast cancers. However, clinical responses to drugs targeting this pathway have been modest, possibly because of dynamic changes in cellular signaling that drive resistance and limit drug efficacy. Using a quantitative chemoproteomics approach, we mapped kinome dynamics in response to inhibitors of this pathway and identified signaling changes that correlate with drug sensitivity. Maintenance of AURKA after drug treatment was associated with resistance in breast cancer models. Incomplete inhibition of AURKA was a common source of therapy failure, and combinations of PI3K, AKT or mTOR inhibitors with the AURKA inhibitor MLN8237 were highly synergistic and durably suppressed mTOR signaling, resulting in apoptosis and tumor regression in vivo. This signaling map identifies survival factors whose presence limits the efficacy of targeted therapies and reveals new drug combinations that may unlock the full potential of PI3K-AKT-mTOR pathway inhibitors in breast cancer
Gestion des données de recherche en milieu collégial : Réflexions sur la mise en place de services par les bibliothèques
Comprend des références bibliographiques.Communication orale dans la cadre du Congrès des professionnels de l’information, Centre Mont-Royal, Montréal, 30 octobre 2019
Epigenetic and Genetic Factors Predict Women's Salivary Cortisol following a Threat to the Social Self
10.1371/journal.pone.0048597PLoS ONE711
Characterisation of bioenergetic pathways and related regulators by multiple assays in human tumour cells
Background: Alterations in cellular metabolism are considered as hallmarks of cancers, however, to recognize these alterations and understand their mechanisms appropriate techniques are required. Our hypothesis was to determine whether dominant bioenergetic mechanism may be estimated by comparing the substrate utilisation with different methods to detect the labelled carbon incorporation and their application in tumour cells. Methods: To define the bioenergetic pathways different metabolic tests were applied: (a) measuring CO2 production from [1-14C]-glucose and [1-14C]-acetate; (b) studying the effect of glucose and acetate on adenylate energy charge; (c) analysing glycolytic and TCA cycle metabolites and the number of incorporated 13C atoms after [U-13C]-glucose/[2-13C]-acetate labelling. Based on [1-14C]-substrate oxidation two selected cell lines out of seven were analysed in details, in which the highest difference was detected at their substrate utilization. To elucidate the relevance of metabolic characterisation the expression of certain regulatory factors, bioenergetic enzymes, mammalian target of rapamycin (mTOR) complexes (C1/C2) and related targets as important elements at the crossroad of cellular signalling network were also investigated. Results: Both [U-13C]-glucose and [1-14C]-substrate labelling indicated high glycolytic capacity of tumour cells. However, the ratio of certain 13C-labelled metabolites showed detailed metabolic differences in the two selected cell lines in further characterisation. The detected differences of GAPDH, β-F1-ATP-ase expression and adenylate energy charge in HT-1080 and ZR-75.1 tumour cells also confirmed the altered metabolism. Moreover, the highly limited labelling of citrate by [2-13C]-acetate-representing a novel functional test in malignant cells-confirmed the defect of TCA cycle of HT-1080 in contrast to ZR-75.1 cells. Noteworthy, the impaired TCA cycle in HT-1080 cells were associated with high mTORC1 activity, negligible protein level and activity of mTORC2, high expression of interleukin-1β, interleukin-6 and heme oxygenase-1 which may contribute to the compensatory mechanism of TCA deficiency. Conclusions: The applied methods of energy substrate utilisation and other measurements represent simple assay system using 13C-acetate and glucose to recognize dominant bioenergetic pathways in tumour cells. These may offer a possibility to characterise metabolic subtypes of human tumours and provide guidelines to find biomarkers for prediction and development of new metabolism related targets in personalized therapy. © 2016 Jeney et al
Characteristic mTOR activity in Hodgkin-lymphomas offers a potential therapeutic target in high risk disease – a combined tissue microarray, in vitro and in vivo study
BACKGROUND: Targeting signaling pathways is an attractive approach in many malignancies. The PI3K/Akt/mTOR pathway is activated in a number of human neoplasms, accompanied by lower overall and/or disease free survival. mTOR kinase inhibitors have been introduced in the therapy of renal cell carcinoma and mantle cell lymphoma, and several trials are currently underway. However, the pathological characterization of mTOR activity in lymphomas is still incomplete. METHODS: mTOR activity and the elements of mTOR complexes were investigated by immunohistochemistry on tissue microarrays representing different human non-Hodgkin-lymphomas (81 cases) and Hodgkin-lymphomas (87 cases). The expression of phospho-mTOR, phospho-4EBP1, phospho-p70S6K, phospho-S6, Rictor, Raptor and Bcl-2, Bcl-xL, Survivin and NF-kappaB-p50 were evaluated, and mTOR activity was statistically analyzed along with 5-year survival data. The in vitro and in vivo effect of the mTOR inhibitor rapamycin was also examined in human Hodgkin-lymphoma cell lines. RESULTS: The majority (>50%) of mantle cell lymphoma, Burkitt lymphoma, diffuse large B-cell lymphoma, anaplastic large-cell lymphoma and Hodgkin-lymphoma cases showed higher mTOR activity compared to normal lymphoid tissues. Hodgkin-lymphoma was characterized by high mTOR activity in 93% of the cases, and Bcl-xL and NF-kappaB expression correlated with this mTOR activity. High mTOR activity was observed in the case of both favorable and unfavorable clinical response. Low mTOR activity was accompanied by complete remission and at least 5-year disease free survival in Hodgkin-lymphoma patients. However, statistical analysis did not identify correlation beetween mTOR activity and different clinical data of HL patients, such as survival. We also found that Rictor (mTORC2) was not overexpressed in Hodgkin-lymphoma biopsies and cell lines. Rapamycin inhibited proliferation and induced apoptosis in Hodgkin-lymphoma cells both in vitro and in vivo, moreover, it increased the apoptotic effect of chemotherapeutic agents. CONCLUSIONS: Targeting mTOR activity may be a potential therapeutic tool in lymphomas. The presence of mTOR activity probably indicates that the inclusion of mTOR inhibition in the therapy of Hodgkin-lymphomas may be feasible and beneficial, especially when standard protocols are ineffective, and it may also allow dose reduction in order to decrease late treatment toxicity. Most likely, the combination of mTOR inhibitors with other agents will offer the highest efficiency for achieving the best clinical response
Determining the Predominant Conformations of Mortiamides A-D in Solution Using NMR Data and Molecular Modeling Tools
Macrocyclic peptidomimetics have been seriously contributingtoour arsenal of drugs to combat diseases. The search for nature'sdiscoveries led us to mortiamides A-D (found in a novel fungusfrom Northern Canada), which is a family of cyclic peptides that clearlyhave demonstrated impressive pharmaceutical potential. This promptedus to learn more about their solution-state properties as these arecentral for binding to target molecules. Here, we secured and isolatedmortiamide D, and then acquired high-resolution nuclear magnetic resonance(NMR) data to learn more about its structure and dynamics attributes.Sets of two-dimensional NMR experiments provided atomic-level (through-bondand through-space) data to confirm the primary structure, and NMR-drivenmolecular dynamics (MD) simulations suggested that more than one predominantthree-dimensional (3D) structure exist in solution. Further stepsof MD simulations are consistent with the finding that the backbonesof mortiamides A-C also have at least two prominent macrocyclicshapes, but the side-chain structures and dynamics differed significantly.Knowledge of these solution properties can be exploited for drug designand discovery.</br
How Do Gamblers End Gambling: Longitudinal Analysis of Internet Gambling Behaviors Prior to Account Closure Due to Gambling Related Problems
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