Patricia Eugenia Vélez

Prof. Dr. Patricia Eugenia Vélez

orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 October 2011 in BMC Genomics
Verified
Journal Article
Open access
PDF file
PMPedro A. Moreno
Pedro A. Moreno
PVPatricia Eugenia Vélez
Patricia Eugenia Vélez
EMEmber Martínez
Ember Martínez
LGLuis E Garreta
Luis E Garreta
NDNéstor Díaz
Néstor Díaz
FGFelipe García
Felipe García
Several studies have shown that genomes can be studied via a multifractal formalism. Recently, we used a multifractal approach to study the genetic information content of the Caenorhabditis elegans genome. Here we investigate the possibility that the human genome shows a similar behavior to that observed in the nematode.

11 December 2018 in BMC Genomics
Verified
Journal Article
Open access
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FTFabian Tobar Tosse
Fabian Tobar Tosse
PVPatricia Eugenia Vélez
Patricia Eugenia Vélez
EOEliana Ocampo-Toro
Eliana Ocampo-Toro
PMPedro A. Moreno
Pedro A. Moreno
Repetitive DNA sequences (Repeats) are significant regions in the human genome that have a specific genomic distribution, structure, and several binding sites for genome architecture and function. In consequence, the possible configurations of Repeats in specific and dynamic regions like the gene promoters could define footprints for molecular mechanisms, pathways, and cell function beyond their density in the genome. Here we explored the distribution of Repeats in the upstream promoter region of the human coding genes with the aim to identify specific configurations, clusters and functional meaning of those elements. Our method includes structural descriptions, hierarchical clustering, pathway association, and functional enrichment analysis. We report here several configurations of Repeats in the upstream promoter region (UPR), which define 2729 patterns for the 80% of the human coding genes. There are 47 types of Repeats in these configurations, where the most frequent were Alu, Low_complexity, MIR, Simple_repeat, LINE/L2, LINE/L1, hAT-Charlie, and ERV1. The distribution, length, and the high frequency of Repeats in the UPR defines several patterns and clusters, where the minimum frequency of configuration among Repeats was higher than 0.7. We found those clusters associated with cellular pathways and ontologies; thus, it was plausible to determine groups of Repeats to specific functional insights, for example, pathways for Genetic Information Processing or Metabolism shows particular groups of Repeats with specific configurations. Based on these findings, we propose that specific configurations of repetitive elements describe frequent patterns in the upstream promoter for sets of human coding genes, which those correlated to specific and essential cell pathways and functions.

30 April 2020 in Biomolecules
Verified
Journal Article
Open access
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CUCarolina Cortes Urrea
Carolina Cortes Urrea
FGFernando Bueno Gutierrez
Fernando Bueno Gutierrez
MSMelissa Solarte
Melissa Solarte
Miguel Eduardo GuevaraMiguel Eduardo Guevara
Miguel Eduardo Guevara
FTFabian Tobar Tosse
Fabian Tobar Tosse
Javier De Las RivasJavier De Las Rivas
Javier De Las Rivas
Cancer is one of the leading causes of mortality worldwide. Breast cancer is the most frequent cancer in women, and in recent years it has become a serious public health problem in Colombia. The development of large-scale omic techniques allows simultaneous analysis of all active genes in tumor cells versus normal cells, providing new ways to discover the drivers of malignant transformations. Whole exome sequencing (WES) was obtained to provide a deep view of the mutational genomic profile in a set of cancer samples from Southwest Colombian women. WES was performed on 52 tumor samples from patients diagnosed with invasive breast cancer, which in most cases (33/52) were ductal luminal breast carcinomas (IDC-LM-BRCA). Global variant call was calculated, and six different algorithms were applied to filter out false positives and identify pathogenic variants. To compare and expand the somatic tumor variants found in the Colombian cohort, exome mutations and genome-wide expression alterations were detected in a larger set of tumor samples of the same breast cancer subtype from TCGA (that included DNA-seq and RNA-seq data). Genes with significant changes in both the mutational and expression profiles were identified, providing a set of genes and mutations associated with the etiology of ductal luminal breast cancer. This set included 19 single mutations identified as tumor driver mutations in 17 genes. Some of the genes (ATM, ERBB3, ESR1, TP53) are well-known cancer genes, while others (CBLB, PRPF8) presented driver mutations that had not been reported before. In the case of the CBLB gene, several mutations were identified in TCGA IDC-LM-BRCA samples associated with overexpression of this gene and repression of tumor suppressive activity of TGF-β pathway.

3 June 2025 in Applied Sciences
Verified
Journal Article
Open access
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KCKebin Contreras
Kebin Contreras
JGJulio Gutierrez-Rengifo
Julio Gutierrez-Rengifo
OCO Casanova-Carvajal
O Casanova-Carvajal
AAAngel Luis Alvarez
Angel Luis Alvarez
PVPatricia Eugenia Vélez
Patricia Eugenia Vélez
ABAna Lorena Urbano Bojorge
Ana Lorena Urbano Bojorge
Glioblastoma, IDH-wildtype (GBM), is the most aggressive and complex brain tumour classified by the World Health Organization (WHO), characterised by high mortality rates and diagnostic limitations inherent to invasive conventional procedures. Early detection is essential for improving patient outcomes, underscoring the need for non-invasive diagnostic tools. This study presents a convolutional neural network (CNN) specifically optimised for GBM detection from T1-weighted magnetic resonance imaging (MRI), with systematic evaluations of layer depth, activation functions, and hyperparameters. The model was trained on the RSNA-MICCAI data set and externally validated on the Erasmus Glioma Database (EGD), which includes gliomas of various grades and preserves cranial structures, unlike the skull-stripped RSNA-MICCAI images. This morphological discrepancy demonstrates the generalisation capacity of the model across anatomical and acquisition differences, achieving an F1-score of 0.88. Furthermore, statistical tests, such as Shapiro–Wilk, Mann–Whitney U, and Chi-square, confirmed the absence of demographic bias in model predictions, based on p-values, confidence intervals, and statistical power analyses supporting its demographic fairness. The proposed model achieved an area under the curve–receiver operating characteristic (AUC-ROC) of 0.63 on the RSNA-MICCAI test set, surpassing all prior results submitted to the BraTS 2021 challenge, and establishing a reliable and generalisable approach for non-invasive GBM detection.

14 April 2025 in Life
Verified
Journal Article
Open access
PDF file
KCKebin Contreras
Kebin Contreras
PVPatricia Eugenia Vélez
Patricia Eugenia Vélez
OCO Casanova-Carvajal
O Casanova-Carvajal
AAAngel Luis Alvarez
Angel Luis Alvarez
ABAna Lorena Urbano Bojorge
Ana Lorena Urbano Bojorge
Background: Glioblastoma multiforme (GBM) is an aggressive brain tumor with a poor prognosis. Traditional diagnosis relies on invasive biopsies, which pose surgical risks. Advances in artificial intelligence (AI) and machine learning (ML) have improved non-invasive GBM diagnosis using magnetic resonance imaging (MRI), offering potential advantages in accuracy and efficiency. Objective: This review aims to identify the methodologies and technologies employed in AI-based GBM diagnostics. It further evaluates the performance of AI models using standard metrics, highlighting both their strengths and limitations. Methodology: In accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, a systematic review was conducted across major academic databases. A total of 104 articles were identified in the initial search, and 15 studies were selected for final analysis after applying inclusion and exclusion criteria. Outcomes: The included studies indicated that the signal T1-weighted imaging (T1WI) is the most frequently used MRI modality in AI-based GBM diagnostics. Multimodal approaches integrating T1WI with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) have demonstrated improved classification performance. Additionally, AI models have shown potential in surpassing conventional diagnostic methods, enabling automated tumor classification and enhancing prognostic predictions.

1 November 2024 in JPRAS Open
Verified
Journal Article
Open access
AGAlan Gonzalez
Alan Gonzalez
LOLaura Ortega-Muñoz
Laura Ortega-Muñoz
DQDaniela Quibano-Ordoñez
Daniela Quibano-Ordoñez
PMPedro A. Moreno
Pedro A. Moreno
PVPatricia Eugenia Vélez
Patricia Eugenia Vélez
The impact of breast implants on the immune system has been debated since their introduction in the 1960s, linking silicone to systemic autoimmune diseases. Recent studies have shown that silicone gel can migrate from the implant capsule, triggering immune responses by proliferating immune cells and releasing cytokines, affecting T-cell function. Silicone particles can induce the release of IL-1 beta and activate the NALP3 inflammasome and B cells, causing an imbalance in regulatory T cells, responder T cells, and Th17 cells. A 41-year-old female patient with a history of breast implants presented with hyperpigmented, irregular, expanding lesions and was diagnosed withmorphea in 2017. The patient also experienced symptoms such as headaches, vertigo, polyarticular pain, dry skin, and fatigue. The medical history included silicone breast implants in 2005 (PIP brand, 395 cc) and 2014 (Silimed brand, 325 cc). The patient was diagnosed with psoriasis and Sj & ouml;gren's syndrome in 2018, and ASIA syndrome in 2021 and subsequently underwent implant removal, leading to clinical improvement. The patient exhibited poliautoimmunity, with multiple autoimmune con ditions. Postsurgery, the patient experienced controlled polyarticu- lar pain, with no new skin plaques and improved clinical status. The temporal correlation between implant placement and autoim- mune symptoms, alongside clinical improvement post-breast im- plant removal, supports the hypothesis that implants function as immune adjuvants. Genetic susceptibility and environmental fac- tors, such as silicone exposure, likely contribute to this pathology. This case highlights the potential for silicone implants to act as im- mune adjuvants and highlights the importance of multidisciplinary approaches in diagnosing and treating patients with autoimmune manifestations and exposure to adjuvants. (c) 2024 The Authors. Published by Elsevier Ltd on behalf of British Association of Plastic, Reconstructive and Aesthetic Surgeons. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)