130,509 research outputs found
An update on therapeutic opportunities offered by cancer glycolytic metabolism
No full textAlmost all invasive cancers, regardless of tissue origin, are characterized by specific modifications of their cellular energy metabolism. In fact, a strong predominance of aerobic glycolysis over oxidative phosphorylation (Warburg effect) is usually associated with aggressive tumour phenotypes. This metabolic shift offers a survival advantage to cancer cells, since they may continue to produce energy and anabolites even when they are exposed to either transient or permanent hypoxic conditions. Moreover, it ensures a high production rate of glycolysis intermediates, useful as building blocks for fast cell proliferation of cancer cells. This peculiar metabolic profile may constitute an ideal target for therapeutic interventions that selectively hit cancer cells with minimal residual systemic toxicity. In this review we provide an update about some of the most recent advances in the discovery of new bioactive molecules that are able to interfere with cancer glycolysis
Homolytic aromatic alkylation of 1- and 2-alkoxynaphthalenes by manganese(III) oxidation of methanes or ethanes 1,1-disubstituted with electron-withdrawing groups
No full textThermal decompn. of Mn(OAc)3 in AcOH in the presence of MeCH(CO2Et)2 or CH2RR1 (R = Ac, R1 = H, Ac, CO2Et; R = CO2Et, R1 = cyano, CO2Et) and alkoxynaphthalenes I (R2 = H, R3 = OMe, OEt) and II (R4 = H, R5 = OMe, OCMe3) gave arom. substitution products, e.g., I [R2 = CMe(CO2Et)2, CHRR1, CRR1OAc, R3 = OMe, OEt] and II [R4 = CH(CO2Et)2, C(OAc)(CO2Et)2, R5 = OMe, OCMe3]. These reactions can also be performed with Mn(III) acetylacetonate and acetoacetate complexe
New developments in HPLC technology
No full textA review with no refs. The new technol. developments in HPLC, mainly the use of computerized methodol., and instrumental characteristics are discussed. As examples, two practical chem. and biochem. applications are reported. The chem. example refers to the det. of kinetic parameters in the diethylnafthoxyethyl malonate with Mn(OAc)3. The biochem. application refers to the detn. of urinary cothecholamines with C18-microcolumns and amperometric detecto
Manganese(III) acetate-induced cyclization of α-(arylalkyl) and α-(aryloxy)alkyl β-dicarbonyl derivatives
No full textThe oxidation of the title compounds by manganese(III) acetate in acetic acid at 50-80°C affords products of intramolecular aromatic alkylation. High yield and selectivity are observed in six-membered ring closures, whereas five- and seven-membered ring closures are associated with side products of dimerization and/or hydrogen abstraction. The aromatic substitution is favored in all cases by a high electron density of the aromatic carbon atom a to the carbonylalkyl substituent. The activation parameters for the oxidative cyclization of diethyl α-(2-naphthoxyethyl)malonate were determined (ΔH‡ = 25.2 ± 0.3 kcal/mol, ΔS‡ = 2.1 ± 0.5 cal/K mol). The reaction is interpreted to proceed through electrophilic Mn(III)-complexed β-dicarbonylalkyl radicals, formed by reversible inner-sphere electron transfer of Mn(III) carbonyl complexes, which add reversibly to the aromatic rin
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Scholarly Communication and Publishing Lunch and Learn Talk #11: The ULS Open Access Author Fee Fund
No full textAt the May 2014 talk, you will learn about the ULS Open Access Author Fee Fund--what it is, why we do it, how it works, and how the program is going so far
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