1,721,006 research outputs found
Mitochondrial caseinolytic protease p: A possible novel prognostic marker and therapeutic target in cancer
Full text linkCaseinolytic protease P (ClpP) is a mitochondrial serine protease. In mammalian cells, the heterodimerization of ClpP and its AAA+ ClpX chaperone results in a complex called ClpXP, which has a relevant role in protein homeostasis and in maintaining mitochondrial functionality through the degradation of mitochondrial misfolded or damaged proteins. Recent studies demonstrate that ClpP is upregulated in primary and metastatic human tumors, supports tumor cell proliferation, and its overexpression desensitizes cells to cisplatin. Interestingly, small modulators of ClpP activity, both activators and inhibitors, are able to impair oxidative phosphorylation in cancer cells and to induce apoptosis. This review provides an overview of the role of ClpP in regulating mitochondrial functionality, in supporting tumor cell proliferation and cisplatin resistance; finally, we discuss whether this protease could represent a new prognostic marker and therapeutic target for the treatment of cancer
Is acetyl-L-carnitine able to reduce oxidative stress in the liver of aging rat by favouring mitochondrial biogenesis?
No full textAge, mitochondria and bladder cancer
Full text linkBladder cancer (BC) is a major cause of mortality worldwide. Risk factors for BC development are male gender, age and exposure to carcinogens and especially cigarette smoking. Since it is not clearly understood why aging is an important BC risk factor, in this review we try to find common features between BC and aging. Evidence suggest that oxidative stress and mitochondrial dysfunction may link aging to BC, thus opening new perspectives in terms of preventive measures and novel potential therapeutic targets
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
DmTTF, a novel mitochondrial transcription termination factor that recognises two sequences of Drosophila melanogaster mitochondrial DNA
Full text linkUsing a combination of bioinformatic and molecular biology approaches a Drosophila melanogaster
protein, DmTTF, has been identified, which exhibits sequence and structural similarity with two mitochondrial
transcription termination factors, mTERF (human) and mtDBP (sea urchin). Import/processing
assays indicate that DmTTF is synthesised as a precursor of 410 amino acids and is imported into
mitochondria, giving rise to a mature product of 366 residues. Band-shift and DNase I protection experiments
show that DmTTF binds two homologous, short, non-coding sequences of Drosophila mitochondrial
DNA, located at the 3' end of blocks of
genes transcribed on opposite strands. The location of the target sequences coincides with that of two of
the putative transcription termination sites previously hypothesised. These results indicate that DmTTF is the termination factor of mitochondrial
transcription in Drosophila. The existence of two DmTTF binding sites might serve not only to stop
transcription but also to control the overlapping of a large number of transcripts generated by the
peculiar transcription mechanism operating in this organism
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