1,721,220 research outputs found
Letter to the editor. ASA scores in the preoperative patient: feedback to clinicians can improve data quality
No full textComputer-aided diagnosis of prostate cancer using multiparametric MRI and clinical features:A patient-level classification framework
No full textComputer-aided diagnosis (CAD) of prostate cancer (PCa) using multiparametric magnetic resonance imaging (mpMRI) is actively being investigated as a means to provide clinical decision support to radiologists. Typically, these systems are trained using lesion annotations. However, lesion annotations are expensive to obtain and inadequate for characterizing certain tumor types e.g. diffuse tumors and MRI invisible tumors. In this work, we introduce a novel patient-level classification framework, denoted PCF, that is trained using patient-level labels only. In PCF, features are extracted from three-dimensional mpMRI and derived parameter maps using convolutional neural networks and subsequently, combined with clinical features by a multi-classifier support vector machine scheme. The output of PCF is a probability value that indicates whether a patient is harboring clinically significant PCa (Gleason score ≥3+4) or not. PCF achieved mean area under the receiver operating characteristic curves of 0.79 and 0.86 on the PICTURE and PROSTATEx datasets respectively, using five-fold cross-validation. Clinical evaluation over a temporally separated PICTURE dataset cohort demonstrated comparable sensitivity and specificity to an experienced radiologist. We envision PCF finding most utility as a second reader during routine diagnosis or as a triage tool to identify low-risk patients who do not require a clinical read.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Prostatic high-resolution micro-ultrasound: an attractive step-forward in the management of prostate cancer patients
No full textProstatic high resolution micro-ultrasound (MUS) was first described by Pavlovich et al. in 2014 [1]. Thanks to scanners operating at high frequency (29 MHz) and the resulting real-time spatial resolution up to 70 microns (near 300% higher than existing platforms) it allows to better evaluate the microstructures and tissue planes. Consequently, MUS is capable of highlighting the alterations of the prostatic histology that are typically associated with high-grade prostate cancer (PCa) such as loss of normal acinar lumen and tighter cellular packing
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Augmenting the Effect of Sonodynamic Therapy for the Treatment of Prostate Cancer
No full textSonodynamic therapy (SDT) uses low-intensity ultrasound to activate sensitisers and generate reactive oxygen species (ROS), inducing targeted cytotoxicity. Nanoparticle-based delivery improves hydrophobic drug solubility and enhances tumour accumulation via the enhanced permeability and retention (EPR) effect. This thesis investigates hematoporphyrin-containing poly(L-glutamic acid-L-tyrosine) [Poly(Glu, Tyr)] nanoparticles (HPNPs), designed to exploit tumour-specific features such as hypoxia, acidity, and abundant cathepsin B.
HPNPs are selectively degraded by cathepsin B, particularly under acidic tumour conditions, producing smaller fragments with exposed hematoporphyrin and reduced negative charge. These changes enhance intratumoural diffusion and cellular uptake, facilitating targeted release and efficient ultrasound-triggered ablation. Upon ultrasound exposure, HPNPs generated ROS, particularly singlet oxygen, at levels comparable to free hematoporphyrin, the primary mediator of SDT-induced cytotoxicity. In addition to its therapeutic potential, HPNPs were shown to suppress cell invasion, potentially through effects of Poly(Glu, Tyr) on the post-translational polyglutamylation of tubulins, a hypothesis that requires further investigation.
In vitro SDT across multiple prostate cancer cell lines demonstrated enhanced cytotoxicity under hypoxic and acidic conditions. Analysis of neuroendocrine markers and oxidative stress modulators identified chromogranin A-derived fragments, particularly serpinin and its active pyroglutamated form (pGlu-serpinin), as potential contributors to SDT resistance. Although direct detection of pGlu-serpinin remains challenging, its hypothesised role in attenuating ROS-mediated cytotoxicity may explain increased SDT resistance under hypoxia.
To overcome resistance phenomena, certain inhibitors targeting cellular defence mechanisms were tested. Glutathione depletion offered minimal benefit, whereas inhibition of the ABCG2 efflux pump (Ko143) and mitoKATP channels (5-hydroxydecanoate, 5-HD) significantly enhanced SDT efficacy, especially under hypoxia. In vivo PC3 xenograft studies confirmed these findings: 5-HD co-treatment markedly improved tumour suppression in larger, hypoxic tumours, suggesting mitoKATP activity as a hypoxia-dependent therapeutic target. The combination of SDT and 5-HD induced sustained tumour volume reduction, highlighting its promise as a priming strategy for further combination therapies such as chemotherapy
- …
