1,721,001 research outputs found
Prognostic significance of a signature based on senescence-related genes in colorectal cancer
Full text linkColorectal cancer, recognized as a quintessential age-related disease, underscores the intricate interplay between aging mechanisms and disease pathogenesis. Cellular senescence, a DNA damage-induced cellular stress response, is characterized by cell cycle arrest, the expression of an inflammatory senescence-associated secretory phenotype, and alterations in extracellular matrix metabolism. It is widely recognized as a fundamental and evolutionarily conserved mechanism of aging. Guided by geroscience principles, which assert that the pathogenesis of age-related diseases involves cellular mechanisms of aging, this study delves into the role of senescence-related genes in colon cancer progression. Leveraging a gene set reflective of senescence-associated pathways, we employed uni- and multivariate Cox proportional hazards survival analysis combined with the determination of the false discovery rate to analyze correlations between gene expression and survival. The integrated database of 1130 colon cancer specimens with available relapse-free survival time and relapse event data from ten independent cohorts provided a robust platform for survival analyses. We identified senescence-related genes associated with differential expression levels linked to shorter survival. Our findings unveil a prognostic signature utilizing cellular senescence-related genes (hazard ratio: 2.73, 95% CI 2.12–3.52, p = 6.4E − 16), offering valuable insights into survival prediction in colon cancer. Multivariate analysis underscored the independence of the senescence-related signature from available epidemiological and pathological variables. This study highlights the potential of senescence-related genes as prognostic biomarkers. Overall, our results underscore the pivotal role of cellular senescence, a fundamental mechanism of aging, in colon cancer progression
Role of oxidative-nitrosative stress and downstream pathways in various forms of cardiomyopathy and heart failure.
No full textPCSK9 expression and cancer survival: a prognostic biomarker at the intersection of oncology and geroscience
Full text linkProprotein convertase subtilisin/kexin type 9 (PCSK9) is primarily recognized for its role in cholesterol metabolism; however, emerging evidence suggests it plays a broader role in the regulation of cellular aging mechanisms and the pathogenesis of age-related diseases. Given that cancer is an age-related disease, PCSK9 has garnered attention for its potential impact on tumor progression and patient survival. In this study, we conducted a comprehensive analysis of PCSK9 expression across multiple tumor types, assessing its prognostic significance using RNA sequencing data from The Cancer Genome Atlas (TCGA) and gene expression microarray data from the Gene Expression Omnibus (GEO). Cox proportional hazards regression models and Kaplan–Meier survival analyses were employed to evaluate overall survival (OS) associations. Our findings reveal that elevated PCSK9 expression is associated with improved OS in breast and ovarian cancers, particularly in Luminal B breast cancer subtypes. Conversely, high PCSK9 expression correlates with worse OS in bladder cancer, renal clear cell carcinoma, melanoma, and pancreatic cancer. Notably, while PCSK9 expression is significantly upregulated in melanoma and bladder tumors, it is downregulated in renal clear cell carcinoma, yet relatively higher expression among renal tumors still predicts poorer survival. No significant associations between PCSK9 expression and OS were observed in colon, liver, gastric, lung, prostate, head and neck cancers, or low-grade gliomas in the available datasets.In conclusion, our study identifies PCSK9 as a prognostic biomarker with distinct, tumor-specific survival implications. Its dual role—associating with improved survival in some cancers while correlating with worse outcomes in others—suggests that PCSK9 may influence cancer progression through context-dependent mechanisms. Future research should focus on elucidating the mechanistic underpinnings of these associations and exploring the diagnostic and therapeutic potential of targeting PCSK9 in oncology
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
Resveratrol confers endothelial protection via activation of the antioxidant transcription factor Nrf2
No full textVariations 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
- …
