164 research outputs found

    Breast Cancer Detection by Means of Artificial Neural Networks

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    Breast cancer is a fatal disease causing high mortality in women. Constant efforts are being made for creating more efficient techniques for early and accurate diagnosis. Classical methods require oncologists to examine the breast lesions for detection and classification of various stages of cancer. Such manual attempts are time consuming and inefficient in many cases. Hence, there is a need for efficient methods that diagnoses the cancerous cells without human involvement with high accuracies. In this research, image processing techniques were used to develop imaging biomarkers through mammography analysis and based on artificial intelligence technology aiming to detect breast cancer in early stages to support diagnosis and prioritization of high-risk patients. For automatic classification of breast cancer on mammograms, a generalized regression artificial neural network was trained and tested to separate malignant and benign tumors reaching an accuracy of 95.83%. With the biomarker and trained neural net, a computer-aided diagnosis system is being designed. The results obtained show that generalized regression artificial neural network is a promising and robust system for breast cancer detection. The Laboratorio de Innovacion y Desarrollo Tecnologico en Inteligencia Artificial is seeking collaboration with research groups interested in validating the technology being developed

    DOCK8 deficiency impairs CD8 T cell survival and function in humans and mice

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    In humans, DOCK8 immunodeficiency syndrome is characterized by severe cutaneous viral infections. Thus, CD8 T cell function may be compromised in the absence of DOCK8. In this study, by analyzing mutant mice and humans, we demonstrate a critical, intrinsic role for DOCK8 in peripheral CD8 T cell survival and function. DOCK8 mutation selectively diminished the abundance of circulating naive CD8 T cells in both species, and in DOCK8-deficient humans, most CD8 T cells displayed an exhausted CD45RA+CCR7? phenotype. Analyses in mice revealed the CD8 T cell abnormalities to be cell autonomous and primarily postthymic. DOCK8 mutant naive CD8 T cells had a shorter lifespan and, upon encounter with antigen on dendritic cells, exhibited poor LFA-1 synaptic polarization and a delay in the first cell division. Although DOCK8 mutant T cells underwent near-normal primary clonal expansion after primary infection with recombinant influenza virus in vivo, they showed greatly reduced memory cell persistence and recall. These findings highlight a key role for DOCK8 in the survival and function of human and mouse CD8 T cells

    Estudios sobre violencia en la educación. Enfoques, textos y contextos

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    El concepto de la violencia ha estado sobre la palestra desde el principio de nuestras sociedades. No obstante, en la práctica sus facetas son múltiples y en diversos ámbitos, lo que ha dado lugar a especulaciones acerca de los medios y los fines. Esto mismo incita a reflexionar en lo axiológico, pues la violencia alberga en sí un elemento adicional de arbitrariedad y, por lo tanto, se relaciona con aspectos fundamentales del derecho o los derechos humanos. En los ámbitos educativos han aparecido nuevas formas de violencia personal, que se reflejan en el bullying y el mobbing. En el ámbito universitario, existe un malestar que no se palía con estímulos o clientelismos y que se refiere a un tipo de violencia particular soterrada por las políticas públicas y el intervencionismo del Estado, los cuales han provocado tensiones entre las comunidades académicas; éstas tienen que ver con la defensa de los principios de libertad y autonomía de cátedra e investigación. En algunos casos, dichas voces han formulado críticas a los programas impuestos, ya que éstos se establecen sin reflexionar en los costos sociales que provocan en el trabajo académico y científico. De esas formas de violencia se quiere dar cuenta en esta obra, la cual fue desarrollada por la Red de Cuerpos Académicos en Política, Educación y Universidad

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

    Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

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    Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

    Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

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    There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity
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