1,721,070 research outputs found
Iron and Neurodegeneration: Is Ferritinophagy the Link?
No full textMounting evidence indicates that the lysosome-autophagy pathway plays a critical role in iron release from ferritin, the main iron storage cellular protein, hence in the distribution of iron to the cells. The recent identification of nuclear receptor co-activator 4 as the receptor for ferritin delivery to selective autophagy sheds further light on the understanding of the mechanisms underlying this pathway. The emerging view is that iron release from ferritin through the lysosomes is a general mechanism in normal and tumour cells of different tissue origins, but it has not yet been investigated in brain cells. Defects in the lysosome-autophagy pathway are often involved in the pathogenesis of neurodegenerative disorders, and brain iron homeostasis disruption is a hallmark of many of these diseases. However, in most cases, it has not been established whether iron dysregulation is directly involved in the pathogenesis of the diseases or if it is a secondary effect derived from other pathogenic mechanisms. The recent evidence of the crucial involvement of autophagy in cellular iron handling offers new perspectives about the role of iron in neurodegeneration, suggesting that autophagy dysregulation could cause iron dyshomeostasis. In this review, we recapitulate our current knowledge on the routes through which iron is released from ferritin, focusing on the most recent advances. We summarise the current evidence concerning lysosome-autophagy pathway dysfunctions and those of iron metabolism and discuss their potential interconnections in several neurodegenerative disorders, such as Alzheimer's, Parkinson's and Huntington's diseases; amyotrophic lateral sclerosis; and frontotemporal lobar dementia
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
Association of APOE genotype with blood-brain barrier permeability in neurodegenerative disorders
Full text linkApolipoprotein E (APOE) is recognized for its role in modulating blood-brain barrier (BBB) permeability in vitro, which may have significant implications for the pathogenesis and progression of neurodegenerative disorders. However, evidence in vivo is contrasting. This study explores the impact of APOE genotypes on BBB integrity among 230 participants experiencing cognitive impairment, encompassing cases of Alzheimer's disease (AD) as well as various non-AD neurodegenerative conditions. To assess BBB integrity, we utilized cerebrospinal fluid (CSF)/serum albumin ratios and CSF/serum kappa and lambda free light chains (FLCs) as indirect markers. Our findings show a dose-dependent increase in BBB permeability in individuals carrying the APOE e4 allele, marked by elevated CSF/serum albumin and FLCs ratios, with this trend being especially pronounced in AD patients. These results highlight the association of APOE epsilon 4 with BBB permeability, providing valuable insights into the pathophysiology of neurodegenerative diseases
Evaluation of the Ion Torrent PGM sequencing workflow for the routine rapid detection of BRCA1 and BRCA2 germline mutations
No full textSIRIO(opens in a new window)|View at Publisher|
Export
| Download | Add to List | More...
Experimental and Molecular Pathology
Volume 102, Issue 2, 1 April 2017, Pages 314-320
Evaluation of the Ion Torrent PGM sequencing workflow for the routine rapid detection of BRCA1 and BRCA2 germline mutations (Article)
Zanella, I.ab , Merola, F.a, Biasiotto, G.ab, Archetti, S.a, Spinelli, E.c, Di Lorenzo, D.a
a Biotechnology Laboratory and Department of Diagnostics, Civic Hospital of Brescia, Brescia, Italy
b Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
c Servizio Malattie Rare, Civic Hospital of Brescia, Brescia, Italy
View additional affiliations
Abstract
Purpose Conventional methods used to identify BRCA1/2 germline mutations in hereditary cancers are time-consuming and expensive, due to the large size of the genes. The recent introduction of next generation sequencing (NGS) benchtop platforms is a great promise, which is rapidly revolutionizing genetic screening in diagnostic and clinical applications. We recently transferred our methodology for routine BRCA1/2 mutation screening (denaturing High Performance Liquid Chromatography plus Sanger sequencing) to the Ion Torrent PGM platform with the Ion Ampliseq BRCA1 and BRCA2 panel and tested the performance of the system. Methods We first validated the NGS approach in a cohort of 33 patients who had previously undergone genetic diagnosis in our laboratory by conventional methods. Then, we tested 29 newly diagnosed and uncharacterized patients by NGS, and Sanger sequencing was used to confirm results from the NGS platform. Results In the validation cohort, all previously identified single nucleotide variants, insertions and deletions (also composed of multiple bases and within complex homopolymeric stretches) were identified by NGS in their correct zygosity status except for variants in a complex multinucleotide region within intron 7 of BRCA1 gene. NGS approach was further able to identify previously undetected variants. In the prospective cohort, almost all (99.3%) called variants were confirmed by Sanger. In both cohorts, in addition to the false positive (31) and false negative (110) results in the intron 7 of BRCA1 gene, the NGS method detected 10 false positives, that were solved by Sanger. Conclusions The Ion Torrent PGM NGS approach in BRCA1/2 germline mutation identification is highly sensitive, easy to use, faster and cheaper than traditional approaches. Therefore, according to other recently published works, we highly recommend this system for routine diagnostic testing on BRCA1/2 genes, along with Sanger confirmation of the called variants, and support the usefulness of the approach also in other routine genetic 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
- …
