Publications by authors named "Vergara C"

Accurate reconstruction of the right heart geometry and motion from time-resolved medical images is crucial for diagnostic enhancement and computational analysis of cardiac blood dynamics. Commonly used segmentation and/or reconstruction techniques, exclusively relying on short-axis cine-MRI, lack precision in critical regions of the right heart, such as the ventricular base and the outflow tract, due to its unique morphology and motion. Furthermore, the reconstruction procedure is time-consuming and necessitates significant manual intervention for generating computational domains.

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Objectives: Pediatric tuberculosis (TB) diagnosis is complicated by challenges in obtaining invasive respiratory specimens that frequently contain few Mycobacterium tuberculosis (Mtb) bacilli. We report the diagnostic performance of an Mtb antigen-derived peptide (MAP-TB) assay and its ability to monitor TB treatment response.

Methods: Study cohorts enrolled children who presented with presumptive TB at two hospitals in South Africa from 2012 to 2017 (157 children aged <13 years) and at community-based clinics in the Dominican Republic from 2019 to 2023 (101 children aged <18 years).

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Land use change threatens global biodiversity and compromises ecosystem functions, including pollination and food production. Reduced taxonomic α-diversity is often reported under land use change, yet the impacts could be different at larger spatial scales (i.e.

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Coronavirus disease 2019 is a highly contagious respiratory illness caused by the coronavirus SARS-CoV-2. Symptoms can range from mild to severe and typically appear 2-14 days after virus exposure. While vaccination has significantly reduced the incidence of severe complications, strategies for the identification of new biomarkers to assess disease severity remains a critical area of research.

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Background And Objectives: Structural Valve Deterioration (SVD) is the main limiting factor to the long-term durability of the bioprosthetic valves used for Transcatheter Aortic Valve Implantation (TAVI), a minimally invasive technique for the treatment of severe aortic stenosis. The aim of this retrospective study is to perform patient-specific computational analyses of blood dynamics shortly after TAVI to identify hemodynamic indices that correlate with a premature onset of SVD which is detected at 5-10 years long-term follow-up exam after TAVI.

Methods: The study population comprises fourteen patients: seven cases with SVD at long-term follow-up were identified and seven cases without SVD were randomly extracted from the same cohort.

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Background: Pleural effusions are challenging to diagnose, with approximately 20-50% of malignant effusions not diagnosed by cytology. Human epididymal protein 4 (HE4) may be useful in the differential diagnosis of pleural effusions. In serum, this biomarker shows false-positive results in some benign diseases.

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Antibiotic treatment is one of the main causes of intestinal dysbiosis, leading, in turn, to other intestinal alterations given the multiple relationships of the microbiota with gut health. Whey and buttermilk are two by-products from the dairy industry with numerous bioactive components. This study aimed to assess the potential of two formulas, containing a mixture of lactoferrin, milk fat globule membrane (MFGM), and whey or buttermilk, to reverse the negative effects of clindamycin on gut motility, Toll-like receptors () expression, and oxidative stress in the intestine.

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Article Synopsis
  • Dengue is a viral infection that can be mild or severe, and this study focused on pediatric cases during an outbreak in Buenos Aires from March to May 2023.
  • A total of 112 patients were evaluated, mostly boys around 12 years old, with common symptoms including fever, headache, and muscle pain; leukopenia and elevated liver enzymes were the frequent lab findings.
  • Early identification of clinical signs and lab results related to more severe cases is crucial for effective treatment, but no severe dengue cases were reported in this study.
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Mutations in mitochondrial energy-producing genes lead to a heterogeneous group of untreatable disorders known as primary mitochondrial diseases (MD). Leigh syndrome (LS) is the most common pediatric MD and is characterized by progressive neuromuscular affectation and premature death. Here, we show that daily cannabidiol (CBD) administration significantly extends lifespan and ameliorates pathology in two LS mouse models, and improves cellular function in fibroblasts from LS patients.

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In this study, we present a computational framework designed to evaluate virtual scenarios of cardiac resynchronization therapy (CRT) and compare their effectiveness based on relevant clinical biomarkers. Our approach involves electro-mechanical numerical simulations personalized, for patients with left bundle branch block, by means of a calibration obtained using data from Electro-Anatomical Mapping System (EAMS) measures acquired by cardiologists during the CRT procedure, as well as ventricular pressures and volumes, both obtained pre-implantation. We validate the calibration by using EAMS data coming from right pacing conditions.

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OBJECTIVE : The treatment of mitral valve prolapse involves two distinct repair techniques: chordal replacement (Neochordae technique) and leaflet resection (Resection technique). However, there is still a debate in the literature about which is the optimal one. In this context, we performed an image-based computational fluid dynamic study to evaluate blood dynamics in the two surgical techniques.

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Background: Dengue fever remains a significant public health challenge in tropical and subtropical regions, with its transmission dynamics being influenced by both environmental factors and human mobility. The Dominican Republic, a biodiversity hotspot in the Caribbean, has experienced recurrent dengue outbreaks, yet detailed understanding of the virus's transmission pathways and the impact of climatic factors remains limited. This study aims to elucidate the recent transmission dynamics of the dengue virus (DENV) in the Dominican Republic, utilizing a combination of genomic sequencing and epidemiological data analysis, alongside an examination of historical climate patterns.

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Pulmonary valve replacement (PVR) consists of substituting a patient's original valve with a prosthetic one, primarily addressing pulmonary valve insufficiency, which is crucially relevant in Tetralogy of Fallot repairment. While extensive clinical and computational literature on aortic and mitral valve replacements is available, PVR's post-procedural haemodynamics in the pulmonary artery and the impact of prosthetic valve dynamics remain significantly understudied. Addressing this gap, we introduce a reduced Fluid-Structure Interaction (rFSI) model, applied for the first time to the pulmonary valve.

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Accurate modeling of blood dynamics in the coronary microcirculation is a crucial step toward the clinical application of in silico methods for the diagnosis of coronary artery disease. In this work, we present a new mathematical model of microcirculatory hemodynamics accounting for microvasculature compliance and cardiac contraction; we also present its application to a full simulation of hyperemic coronary blood flow and 3D myocardial perfusion in real clinical cases. Microvasculature hemodynamics is modeled with a compliant multi-compartment Darcy formulation, with the new compliance terms depending on the local intramyocardial pressure generated by cardiac contraction.

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Purpose: COVID-19 continues to affect millions of individuals worldwide, both in the short and long term. The post-acute complications of SARS-CoV-2 infection, referred to as long COVID, result in diverse symptoms affecting multiple organ systems. Little is known regarding how the symptoms associated with long COVID progress and resolve over time.

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During ripening, 'Hass' avocado skin changes from green to purple/black. Low-temperature storage with a controlled atmosphere (CA) is the most widely used method for avocado storage; however, few studies have simulated this technology and considered the days of regular air (RA) storage prior to CA storage. Herein, the effect of delaying the storage of 'Hass' avocado (>30% dry matter) in a CA was examined.

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Purpose: COVID-19 disease continues to affect millions of individuals worldwide, both in the short and long term. The post-acute complications of SARS-CoV-2 infection, referred to as long COVID, result in diverse symptoms affecting multiple organ systems. Little is known regarding how the symptoms associated with long COVID progress and resolve over time.

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Nearly 300 million individuals live with chronic hepatitis B virus (HBV) infection (CHB), for which no curative therapy is available. As viral diversity is associated with pathogenesis and immunological control of infection, improved methods to characterize this diversity could aid drug development efforts. Conventionally, viral sequencing data are mapped/aligned to a reference genome, and only the aligned sequences are retained for analysis.

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Impaired cardiac function has been described as a frequent complication of COVID-19-related pneumonia. To investigate possible underlying mechanisms, we represented the cardiovascular system by means of a lumped-parameter 0D mathematical model. The model was calibrated using clinical data, recorded in 58 patients hospitalized for COVID-19-related pneumonia, to make it patient-specific and to compute model outputs of clinical interest related to the cardiocirculatory system.

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Background And Objective: In the current work, we present a descriptive fluid-structure interaction computational study of the end-to-side radio-cephalic arteriovenous fistula. This allows us to account for the different thicknesses and elastic properties of the radial artery and cephalic vein.

Methods: The core of the work consists in simulating different arteriovenous fistula configurations obtained by virtually varying the anastomosis angle, i.

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In searching for compounds with antioxidant and antifungal activity, our study focused on the subshrub species Vahl ex Willd. (Ericaceae). We measured the antioxidant activity of its methanolic extract (MEE) obtained from the aerial parts (leaves and stems) and of its methanolic extract (MEF) obtained from the lyophilized fruits.

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This work reports an optimized method to experimentally quantify the Gd-nanoparticle dose enhancement generated by electronic brachytherapy. The dose enhancement was evaluated considering energy beams of 50 kVp and 70 kVp, determining the Gd-nanoparticle concentration ranges that would optimize the process for each energy. The evaluation was performed using delaminated radiochromic films and a Poly(methyl methacrylate) (PMMA) phantom covered on one side by a thin 2.

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Introduction: Fractional Flow Reserve (FFR) is used to characterize the functional significance of coronary artery stenoses. FFR is assessed under hyperemic conditions by invasive measurements of trans-stenotic pressure thanks to the insertion of a pressure guidewire across the coronary stenosis during catheterization. In order to overcome the potential risk related to the invasive procedure and to reduce the associated high costs, three-dimensional blood flow simulations that incorporate clinical imaging and patient-specific characteristics have been proposed.

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