Publications by authors named "Barajas R"
COI-barcode-like sequences appear to show substantially more species diversity among Mesoamerican bumblebees than had been reported previously from morphological studies. Closer examination shows that some of this apparent diversity may be pseudospecies (groups falsely misinterpreted as separate species), often supported by paralogous 'numts' (nuclear copies of mitochondrial sequences). For the well-sampled weisi-complex, we seek to filter out pseudogenes in order to use the orthologous COI-barcode sequences for identifying estimates of evolutionary relationships and likely species' gene coalescents for candidate species.
View Article and Find Full Text PDFLatinas are less likely to receive genetic counseling and genetic testing (GCT) compared to non-Latina Whites because of systemic and patient-level barriers. We developed and tested fotonovelas to increase awareness of GCT among Latinas at-risk of hereditary breast and ovarian cancer (HBOC). Content for the fotonovelas was drawn from an existing culturally targeted narrative video focused on improving GCT use among Latinas at-risk of HBOC.
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- This study introduces a new way to classify patients with a type of brain cancer called IDH-wildtype glioblastomas by looking at how much of the tumor is removed during surgery.
- It involves 622 patients from one hospital and another 536 patients from three different hospitals, all of whom received standard cancer treatments and had tests to check their tumor characteristics.
- The new classification model shows that younger patients with certain tumor features have a better chance of living longer after surgery, compared to older patients or those with less successful surgeries.
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- * Imaging genomics explores how genetic and molecular features relate to imaging data, potentially transforming brain tumor diagnosis and treatment.
- * The article reviews imaging genomics methods, recommends analytic techniques, discusses their clinical relevance, and proposes future research directions in tumor habitat analysis.
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- The study compares the effectiveness of two contrast agents, Gadolinium (GBCA) and Ferumoxytol (FBCA), in enhancing MRI images for high-grade glioma at different field strengths (3T and 7T).
- It involved 10 patients, where lesions received both GBCA on the first day and varying doses of FBCA on the second day; CNR and nCBV were analyzed for different types of lesions.
- Results showed GBCA provided higher contrast-to-noise ratio (CNR) than FBCA at 7T, but both agents had similar performances at 3T, particularly with the higher dosage of FBCA being most effective for imaging.
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- Individuals with serious mental illness (SMI) who encounter the criminal justice system can benefit from targeted mental health interventions, but more research is needed to determine their overall effectiveness.
- The review identified 13 studies focusing on various intervention types, such as cognitive/behavioral and psychoeducational approaches, with some showing significant mental health improvements, particularly those using interpersonal therapy (IPT).
- Challenges in evaluating these interventions include the need for larger, randomized studies and the inclusion of non-clinical personnel, emphasizing gaps in the current mental health treatment literature for this population.
Background: Ultrasound can overcome barriers to visualizing the internal jugular vein, allowing hepato-jugular reflux and jugular venous pressure measurement. We aimed to determine operating characteristics of the ultrasound hepato-jugular reflux and ultrasound jugular venous pressure predicting right atrial and pulmonary capillary occlusion pressures.
Methods: In a prospective observational cohort at three US academic hospitals the hepato-jugular reflux and jugular venous pressure were measured with ultrasound before right heart catheterization.
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- MRI is commonly used in high-grade glioma treatments to map tumor boundaries and assist in surgery, revealing important tumor biology through its measurements.
- The study found that specific MRI techniques (like T1+C) not only visualize the tumor's blood flow disruption but also indicate immune cell infiltration, enhancing our understanding of how these factors interact within the tumor environment.
- The research offers a new, unbiased methodology for linking MRI results with tumor biology, laying the groundwork for future advancements in noninvasive diagnostics and treatment strategies for patients with high-grade gliomas.
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- MRI with gadolinium (Gd) is commonly used to monitor glioblastoma treatment but lacks specificity in revealing the tumor's immune environment; ferumoxytol (Fe), an iron nanoparticle, targets macrophages and microglia within glioblastomas.
- In a study involving stereotactic biopsy samples and RNA microarray analysis, researchers examined how different MRI contrast agents (Gd versus Fe) correlated with immune pathways and gene expression patterns in glioblastoma patients.
- Findings indicated that Fe-enhanced imaging provided a better understanding of immune processes, showing higher levels of immune-related gene sets and M2 polarized macrophages, highlighting its potential to inform treatment and tumor biology more effectively than standard Gd-based imaging.
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- Poor clinical outcomes in glioblastoma patients may result from issues within the tumor's immune environment; understanding this could lead to better patient assessment through imaging techniques.
- The study involved patients with newly diagnosed glioblastoma who underwent MRI and tissue sampling to analyze gene expression and identify different immune signatures associated with specific MRI features.
- Results showed that different MRI phenotypes correlate with varying immune responses, with enhancing lesions reflecting a stronger immune signature compared to non-enhancing areas, indicating that MRI can be a valuable tool for assessing glioblastoma's immune microenvironment.
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- Pulsed field ablation (PFA) is a heart treatment showing promise for safety, but concerns exist about its potential to create harmful gas microbubbles that may lead to brain emboli.
- In an experiment using swine models, researchers monitored the effects of PFA in the left ventricle, finding that PFA didn’t produce any microbubbles or associated cerebral abnormalities, while control swine injected with air microbubbles did show signs of brain emboli.
- The study concluded that PFA, when applied to both healthy and heart-injured tissues, doesn’t appear to cause brain emboli, suggesting it may be a safer option for cardiac procedures.
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- Pathogenic mutations in key genes linked to Lynch syndrome impair DNA mismatch repair and increase cancer risk, including endometrial and colorectal cancers.
- A case study highlights an adult female with no previous cancer history who developed a multicentric glioma in different brain regions, showing distinct tumor characteristics but sharing a common genetic mutation associated with Lynch syndrome.
- The findings underscore the relevance of genetic profiling in gliomas, demonstrating that mismatched repair gene alterations may play a crucial role in the development of these brain tumors.
The African turquoise killifish () is the shortest-lived vertebrate bred in captivity, with a median life span of 4-6 mo. Within its short life span, the killifish recapitulates critical aspects of human aging, including neurodegeneration and increased frailty. Developing standardized protocols for life span assessment in killifish is critical for identifying environmental and genetic factors that impact vertebrate life span.
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- Conventional MRI is useful for assessing multiple sclerosis (MS), but it has limitations in detecting early neurodegeneration and mainly shows late-stage brain atrophy.
- There is a pressing need for biomarkers that can identify neurodegenerative processes before they become irreversible, particularly with the role of oxidative stress in MS pathogenesis being underexplored.
- Recent advancements in imaging markers related to inflammation and neuronal integrity highlight the potential for non-invasive imaging to assess oxidative stress in real-time, which could enhance the understanding and management of MS and other neurodegenerative diseases.
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- CE-MRI is the preferred imaging method for diagnosing and monitoring primary central nervous system lymphoma, but it may not accurately reflect the true tumor size due to its reliance on specific anatomical measurements.
- While standard T1 and T2 MRI techniques are commonly used, incorporating additional methods like diffusion-weighted and perfusion-weighted imaging could enhance understanding of tumor behavior and response to treatment.
- There is a pressing need for standardizing imaging practices and reporting, as current inconsistencies hinder effective treatment planning and clinical trial outcomes for patients with PCNSL.
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- Response assessment after immunotherapy for glioblastoma is difficult due to the occurrence of pseudoprogression, which can complicate diagnosis.
- Current imaging methods like gadolinium-enhanced MRI are limited in their ability to accurately characterize this condition.
- A study using FMISO PET showed potential for measuring hypoxia in tumors, indicating that it could help differentiate between pseudoprogression and actual tumor recurrence more effectively.
Background: Through the systematic large-scale profiling of metabolites, metabolomics provides a tool for biomarker discovery and improving disease monitoring, diagnosis, prognosis, and treatment response, as well as for delineating disease mechanisms and etiology. As a downstream product of the genome and epigenome, transcriptome, and proteome activity, the metabolome can be considered as being the most proximal correlate to the phenotype. Integration of metabolomics data with other -omics data in multi-omics analyses has the potential to advance understanding of human disease development and treatment.
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- High-grade glioma (HGG) patients often have similar MRI results for disease progression and treatment-related changes, complicating treatment response evaluations.* -
- The review analyzed 28 studies, involving 638 patients with true progression and 430 with treatment-related changes, to assess the effectiveness of dynamic susceptibility contrast (DSC) MRI.* -
- Results showed DSC MRI had a combined area under the receiver operating curve (AUROC) of 0.85, with sensitivity and specificity rates of 0.84 and 0.78, respectively, indicating it is effective in distinguishing between true tumor progression and treatment-related changes.*
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- PET imaging is now a key diagnostic tool in precise medicine, with various pre-targeting methods developed to improve traditional immuno-PET's limitations.
- The new Dual-Receptor Pre-Targeting (DRPT) system enhances tumor radioligand uptake and retention by using a tumor-receptor-specific peptide, outperforming previous methods.
- DRPT is compatible with short-lived isotopes, could reduce the necessary amount of pre-administered antibodies, and offers a potential cost-saving approach in antibody-based molecular imaging.
Systems epidemiology offers a more comprehensive and holistic approach to studies of cancer in populations by considering high dimensionality measures from multiple domains, assessing the inter-relationships among risk factors, and considering changes over time. These approaches offer a framework to account for the complexity of cancer and contribute to a broader understanding of the disease. Therefore, NCI sponsored a workshop in February 2019 to facilitate discussion about the opportunities and challenges of the application of systems epidemiology approaches for cancer research.
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- The article discusses the challenges faced in imaging brain tumors due to the rise of immune-modulating therapies and the need for personalized treatment plans.
- It highlights the limitations of existing imaging techniques like gadolinium contrast-enhanced MRI and FDG PET, and emphasizes the importance of understanding the tumor's interaction with the immune system.
- The article aims to provide insights on imaging methods for detecting neuroinflammation in brain tumors and offers practical guidance on using iron nanoparticle imaging as a tool for diagnosing and monitoring these malignancies.
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- A case study of a 6-year-old girl presented severe symptoms from a high-grade AVM, leading to surgery and initial SRS treatment, but she later developed recurrent symptoms due to a new AVM nidus.
- The treatment for her persistent RIN shifted from steroids to bevacizumab, resulting in a significant improvement in her symptoms and reduced side effects associated with long-term steroid use.
Objectives: Systems epidemiology approaches may lead to a better understanding of the complex and dynamic multi-level constellation of contributors to cancer risk and outcomes and help target interventions. This grant portfolio analysis aimed to describe the National Institutes of Health (NIH) and the National Cancer Institute (NCI) investments in systems epidemiology and to identify gaps in the cancer systems epidemiology portfolio.
Methods: The analysis examined grants funded (2013-2018) through seven NIH systems science Funding Opportunity Announcements (FOAs) as well as cancer-specific systems epidemiology grants funded by NCI during that same time.