Repositorio Institucional
Nuestra plataforma Reúne, conserva y difunde la producción intelectual en formato digital de estudiantes, académicos e investigadores de la Universidad del Desarrollo. Es una plataforma web colaborativa diseñada y administrada por el Sistema de Bibliotecas, en el que participan las unidades académicas como proveedoras de contenido, ejerciendo el rol de editor en su respectiva “comunidad” Leer Más...
¿Qué estás buscando?
Recent Submissions
How I Do It: Evaluating Cardiac Implantable Devices and Noncardiac Mimics on Chest Radiographs
(2025) Silva, Claudio; Christensen, Jared
Cardiac implantable electronic devices (CIEDs), including pacemakers and defibrillators, are increasingly used to manage various cardiac conditions. This article reviews the radiographic appearance, typical components, and placement of CIEDs, including newer technologies like leadless pacemakers and MRI-conditional devices. The article also highlights the imaging findings of common complications such as lead dislodgement, fracture, and perforation, emphasizing the role of imaging in early detection and intervention. Additionally, the radiographic identification of other cardiac and noncardiac devices with similar-appearing imaging features is addressed. Other cardiac devices covered in this article include those for cardiac monitoring, ventricular assistance, and cardiac repair. Noncardiac mimics include deep brain, vagal nerve, and phrenic nerve stimulators as well as breast implant radiofrequency markers. Accurately identifying these devices and their positioning on chest radiographs facilitates the early detection of complications and directs appropriate patient care.
Defunciones por hidrocefalia en chile entre 1997 y 2022 y caracterización de variables epidemiológicas
(2026) Ávalos, Nicolás; Betancourt, Lucas; Bello, Winston; Pierotic, Antonia; Gallegos, Juan
Introducción: La hidrocefalia es una enfermedad compleja con prevalencia bimodal que afecta a recién nacidos y adultos mayores y que, a pesar de los avances en tratamiento y prevención, sigue siendo una causa importante de mortalidad en el mundo. En Chile, la información sobre la hidrocefalia sigue siendo escasa desde el punto de vista epidemiológico, generando un vacío de información que puede llevar a errores en la planificación de la salud pública del país. Objetivo: Caracterizar el comportamiento de las defunciones por hidrocefalia en Chile entre 1997 y 2022 para identificar grupos etarios más afectados y proponer medidas de prevención. Metodología: Estudio observacional, descriptivo, ecológico, de serie temporal a partir de datos anónimos obtenidos del Departamento de Estadística e Información en Salud de defunciones por hidrocefalia en Chile entre 1997 y 2022, separándolas en variables por año, rango etario, sexo y región expresadas en tasas de mortalidad. Resultado: Se registraron 707 defunciones, siendo el año 2022 el de tasa máxima (2,5 defunciones por cada millón de
habitantes). Fue más frecuente en hombres (55,9%), el grupo etario más afectado fue el de ≥80 años y la región con mayor tasa de mortalidad fue Biobío. Conclusión: La hidrocefalia sigue siendo un problema de salud pública, que afecta principalmente a hombres mayores de 60 años y cuya causa más frecuente de muerte es por hidrocefalia “No especificada”, lo que evidencia la necesidad de desarrollar un registro epidemiológico más completo y la formulación de estrategias para la prevención de la enfermedad en grupos de riesgo.
Introduction: Hydrocephalus is a complex disease that presents a bimodal prevalence affecting newborns and older adults; which, despite improvements regarding its treatment and prevention, continues to be an important cause of mortality around the world. In Chile, information on hydrocephalus remains scarce from an epidemiological point of view, generating an information gap that can lead to errors in public health planning in the country. Objective: To characterize the behavior of deaths due to hydrocephalus in Chile between 1997 and 2022 to identify the most affected age groups and propose prevention measures. Methodology: An observational, descriptive, ecological, time series study based on anonymous data obtained from Department of Health Statistics and Information of deaths due to hydrocephalus in Chile between 1997 and 2022, separating them into variables by year, age range, sex and region expressed as mortality rates. Result: A total of 707 deaths were recorded, with the year 2022 being the one with the highest rate (2,5 deaths per one million inhabitants). It was more frequent in the male sex (55,9%), the most affected age group was ≥80 years, and the region with the highest mortality rate was Biobío. Conclusion: Hydrocephalus continues to be a public health problem, which mainly affects men over 60 years of age and whose most frequent cause of death is due to “Unspecified” hydrocephalus, which shows the need to develop a more complete epidemiological registry and the formulation of strategies for the prevention of the disease in risk groups.
Magnetic resonance imaging of paraurethral and paravaginal lesion: relevant diagnoses, key findings and surgical correlation
(https://doi.org/10.21037/tau-2024-726, 2025) Labra, Andrés; Cocio, Rolando; Saavedra, Álvaro; Schiappacasse, Giancarlo; Blaskovic, Fernanda
Paraurethral and paravaginal lesions are uncommon entities that often present diagnostic challenges due to their anatomical complexity, varied etiologies, and overlapping clinical presentations. Accurate identification and characterization of these lesions are essential for appropriate management and surgical planning. A structured diagnostic approach, based on clinical history, lesion location, and imaging features, is critical to avoid misdiagnosis and unnecessary interventions. Magnetic resonance imaging (MRI) has emerged as the modality of choice due to its excellent soft-tissue contrast, multiplanar capabilities, and non-invasive nature, offering superior delineation of lesion extent and relationship with adjacent pelvic structures. This pictorial review seeks to support radiologists and clinicians by offering a comprehensive yet practical guide to the imaging evaluation of paraurethral and paravaginal lesions. Through high-resolution MRI images and original anatomical illustrations, we aim to reduce the gap between imaging interpretation and clinical decision-making. We summarize the primary MRI indications for evaluating female urethral pathology, provide an overview of common and rare differential diagnoses, and highlight relevant MRI protocol considerations. Additionally, we include correlations with surgical findings when available, to enhance clinical applicability. Rather than providing an exhaustive catalog of entities, our focus is to promote standardized imaging assessment and highlight key anatomical and diagnostic considerations that may facilitate a more confident and informed multidisciplinary approach to these often-overlooked pelvic pathologies.
CCTA-Guided Selective Invasive Coronary Catheterization: A Strategy to Reduce Contrast Volume and Improve Efficiency
(2025) Dahdal, Jorge; Jukema, Ruurt; Somsen, Aernout; Kooijman, Eline; Wahedi, Ellaha; Lemkes, Jorrit; Raijmakers, Pieter; Heestermans, Ton; Van Royen, Niels; Knaapen, Paul; Danad, Ibrahim
Background: Symptomatic patients with unilateral obstructive coronary artery disease (CAD) identified by coronary computed tomography angiography (CCTA), involving either the right or left coronary artery, typically undergo per-protocol bilateral coronary visualization during invasive coronary angiography (ICA). However, a selective visualization approach may be sufficient. Objectives: The objectives of this study were to assess the accuracy of CCTA in excluding hemodynamically significant coronary stenosis in patients with unilateral CAD and to evaluate whether a CCTA-guided selective ICA strategy can reduce procedure time and contrast agent use. Methods: In this cross-sectional cohort study, 454 patients with clinically suspected stable CAD who underwent CCTA prior to ICA were included. The study population consisted of 190 patients with unilateral obstructive CAD, defined as ≥50% diameter stenosis on CCTA, and an absence of obstructive CAD on the contralateral side. ICA with invasive functional assessment was used as the reference standard. Results: CCTA demonstrated a high accuracy, 97.4% (95% CI: 94-99%), in excluding hemodynamically significant disease in the contralateral arteries without obstructive CAD. Compared to the conventional ICA approach, a CCTA-guided selective visualization strategy resulted in significant reductions in procedure time and contrast agent usage: procedure time and contrast agent usage were reduced by 27% (95% CI: 12.1-47.5%) and 46.8% (95% CI: 27.5-67.0%), respectively. Conclusions: In patients with unilateral obstructive CAD identified by CCTA, a CCTA-guided selective ICA visualization strategy is highly accurate in ruling out hemodynamically significant CAD on the contralateral side. Additionally, this unilateral ICA approach has the potential to reduce both contrast agent usage and procedure time compared to the conventional bilateral visualization strategy.
From cadaveric donation to cryopreserved total skin allografts: Transforming the Chilean skin donation model
(2025) Fonseca, Marcelo; Cañete, Aldo; Mandriaza, Luana; Gómez, Jennifer; Masiá, Jaume; Marcelain, Katherine; Ibaceta, Dino; Erazo, Cristian; Gámez, Brenda; Soto, Carolina; Valdés, Cristóbal
Background: The clinical utility of skin allografts (SA) is well established. However, the donation and procurement of cadaveric skin-historically the primary source of SA-remain limited in many countries. A skin donation model based on the use of excess surgical tissue from body contouring procedures was introduced and compared with the traditional cadaveric donation model.
Methods: A retrospective review of skin donations in Chile was conducted over two periods (2017-2019 and 2022-2024), analyzing the performance and characteristics of two donation pathways: cadaveric and living donors.
Results: During the first period (2017-2019), four cadaveric donors provided a total of 10,959 cm² of skin. In the second period (2022-2024), 353 donors contributed 153,585 cm² of skin, of which 348 were living donors (131,997 cm²) and five were cadaveric (21,588 cm²).
Conclusions: Initially conceived as a complementary strategy, the living donor model has evolved to become the primary source of skin allografts in Chile. This approach significantly increases the availability of SA, broadens therapeutic indications, and promotes the concept of transforming excess surgical tissue into valuable therapeutic resources. Moreover, it enables the production of cryopreserved full-thickness skin allografts (CTSA), which serve not only as temporary wound coverage but also as dermal regenerative scaffolds, particularly beneficial in the treatment of burns affecting functionally and aesthetically critical areas. This new paradigm supports a more accessible and sustainable culture of skin donation while offering promising benefits for regenerative burn care.
Time to Surgery for Subaxial Cervical Fractures: A Multicenter Study
(2025) Quinteros, Guisela; Ricciardi, Guillermo; Cirillo, Ignacio; Marquez, Edgar; Cabrera, Juan; Carazzo, Charles; Yurac, Ratko; Guiroy, Alfredo
Objective: To identify delays for surgery to stabilize subaxial cervical fractures and the main reasons for them across Latin America.
Methods: This is a retrospective multicenter cohort study of patients surgically treated for subaxial cervical fractures from 13 spine centers across Latin America from January 1, 2014 to January 1, 2023. Causes of delay to surgery beyond 24 hours were documented.
Results: We included 529 patients from 13 institutions in Latin American countries; 408 (77.1%) males and 121 (22.9%) females with a mean age of 43.4 (standard deviation = ±16.2). Predominantly caused by traffic accident (n = 256; 48.4%), followed by fall from height (n = 233; 44%). Mostly, suffered type C fractures (n = 348; 65.8%) and/or neurological injury (n = 384; 72.6%). The time from admission to surgery was >72 hours in 70% of the patients included (n = 375; 70.9%). More than 45% waited longer than a week (n = 257; 48.6%) for spine surgery. Only 12.5% (n = 66) of the patients received surgery in the first 24 hours from admission. The primary reasons for the surgical delay were the necessity for other surgical procedures (n = 161; 34.8%), the unavailability of surgical implants (n = 60; 13.0%), patient clinical instability (n = 55; 11.9%), and delays in referral (n = 38; 8.2%).
Conclusions: We documented significant and concerning delays in providing spinal decompression and stabilization surgery to patients with cervical spine fractures. Only 17% of patients have surgery in the recommended time <24 hours, more than half of the patients must wait for more than 72 hours, and nearly half of patients wait for longer than a week.
Predicting Response to Intravesical Bacillus Calmette-Guérin in High-Risk Nonmuscle-Invasive Bladder Cancer Using an Artificial Intelligence-Powered Pathology Assay: Development and Validation in an International 12-Center Cohort
(2025) Lotan, Yair; Krishna, Viswesh; Abuzeid, Waleed; Launer, Bryn; Chang, Sam; Krishna, Vrishab; Shingi, Siddhant; Gordetsk, Jennifer; Gerald, Thomas; Woldu, Solomon; Shkolyar, Eugene; Hayne, Dickon; Redfern, Andrew; Spalding, Lisa; Stewart, Courtney; Eyzaguirre, Eduardo; Imtiaz, Shamsunnahar; Narayan, Vikram; Packiam, Vignesh; O'Donnell, Michael; Li, Roger; Baekelandt, Loic; Joniau, Steven; Zuiverloon. Tahlita; Fernandez, Mario; Schultz, Marcela; Hensley, Patrick; Allison, Derek; Taylor, John; Hamza, Ameer; Kamat, Ashish; Nimgaonkar, Vivek; Sonawane, Snehal; Miller, Daniel; Watson, Drew; Vrabac, Damir; Joshi, Anirudh; Shah, Jay; Williams, Stephen
Purpose: There are few markers to identify those likely to recur or progress after treatment with intravesical bacillus Calmette-Guérin (BCG). We developed and validated artificial intelligence (AI)-based histologic assays that extract interpretable features from transurethral resection of bladder tumor digitized pathology images to predict risk of recurrence, progression, development of BCG-unresponsive disease, and cystectomy.
Materials and methods: Pre-BCG resection-derived whole-slide images and clinical data were obtained for high-risk nonmuscle-invasive bladder cancer cases treated with BCG from 12 centers and were analyzed through a segmentation and feature extraction pipeline. Features associated with clinical outcomes were defined and tested on independent development and validation cohorts. Cases were classified into high or low risk for recurrence, progression, BCG-unresponsive disease, and cystectomy.
Results: Nine hundred forty-four cases (development: 303, validation: 641, median follow-up: 36 months) representative of the intended use population were included (high-grade Ta: 34.1%, high-grade T1: 54.8%; carcinoma in situ only: 11.1%, any carcinoma in situ: 31.4%). In the validation cohort, "high recurrence risk" cases had inferior high-grade recurrence-free survival vs "low recurrence risk" cases (HR, 2.08, P < .0001). "High progression risk" patients had poorer progression-free survival (HR, 3.87, P < .001) and higher risk of cystectomy (HR, 3.35, P < .001) than "low progression risk" patients. Cases harboring the BCG-unresponsive disease signature had a shorter time to development of BCG-unresponsive disease than cases without the signature (HR, 2.31, P < .0001). AI assays provided predictive information beyond clinicopathologic factors.
Conclusions: We developed and validated AI-based histologic assays that identify high-risk nonmuscle-invasive bladder cancer cases at higher risk of recurrence, progression, BCG-unresponsive disease, and cystectomy, potentially aiding clinical decision making
KLHL24 mutation drives intermediate filament degradation, mitochondrial dysfunction and fibrosis in heart failure patients
(2025) Ramovs, Veronika; Chen, Sophia; Patra, Athina; Tjokrodirijo, Rayman; Van Veelen, Peter; Mulder, Aat; Koning, Roman; Stöger, Lauran; Hubner, Catalina; Ibañez, Rodrigo; Morales, Bernardo; Morandé, Pilar; Dell'Oro, Rosario; Poblete, Cristian; Schuster, Andrés; Joao, María; Palisson, Francis; Has, Cristina; Jongbloed, Monique; Fuentes, Ignacia; Mummery, Christine; Raymond, Karine
Aims: A striking aspect of epidermolysis bullosa patients with a mutation in KLHL24 (KLHL24mut) is their life-threatening deterioration of heart function. KLHL24 is a component of the ubiquitin-proteasome system and acts as a substrate-specific adaptor protein for E3 ubiquitin ligase. KLHL24mut is thought to represent a gain-of-function mutation, with associated cardiac and skin pathologies arising from the excessive degradation of its target proteins. Although reduced desmin levels in cardiomyocytes (CMs) have already been documented, the potential involvement of additional mechanisms in KLHL24mut -driven heart pathology remains unexplored.
Methods and results: We report on two patients with KLHL24mut who recently manifested heart failure. To gain insights into their physiopathology, we integrated clinical data with proteomic analyses of heart tissue as well as human induced pluripotent stem cell (hiPSC) models carrying KLHL24mut. Mass spectrometry analysis of CMs differentiated from patient-derived hiPSCs mirrored the proteomic profile of their corresponding left ventricle tissue samples. KLHL24mut resulted in a reduction of several intermediate filaments (IF), mitochondrial and muscle fibre proteins as well as the emergence of an early fibrotic signature. By utilising various hiPSC-derived cardiac models along with flow cytometry, immunofluorescence, and western blot analyses, we confirmed that the excessive proteasomal activity of endogenous KLHL24mut caused a decrease in levels of desmin, synemin and vimentin, IF proteins of CMs and cardiac fibroblasts. Moreover, KLHL24mut led to mitochondrial mislocalization and increased mitophagy, reduced PKA activity, and sarcomere shortening in CMs.
Conclusion: The deterioration of heart function in patients with KLHL24mut is driven by excessive proteasome-dependent degradation of multiple IF proteins across various cardiac cell types. Monotypic hiPSC-derived CMs and end-stage patient-derived cardiac explants from patients exhibit similar features, uncovering early pathological mechanisms and identifying a list of potential novel KLHL24mut target proteins. Finally, our findings validate that hiPSC-derived CMs represent a relevant model for future studies.
T1b gallbladder cancer: is extended resection warranted?
(2025) Chavez, Montserrat; De Aretxabala, Xabier; Losada, Hector; Portillo, Norberto; Castillo, Felipe; Bustos, Luis; Roa, Ivan
Background: Although the prognosis for gallbladder cancer (GBCA) improves with early diagnosis and aggressive surgical treatment, the management of patients with muscle layer invasion (T1b) remains controversial. This study aimed to analyze the optimal surgical approach for these patients.
Methods: A database was queried for patients with early T1b GBCA treated at four Chilean hospitals. Patients were prospectively treated and registered by the same surgical team at each hospital. Clinical outcomes, including survival rates according to the type of surgery, were analyzed.
Results: Between 1988 and 2023, 129 Chilean patients were pathologically diagnosed with T1b GBCA. Simple cholecystectomy (SC) was performed in 86 patients (66.7 %), while extended cholecystectomy (EC) was performed in 43 patients. The overall 5-year survival rate was 83 %, with no significant difference between SC and EC patients.
Conclusion: Simple cholecystectomy demonstrated survival rates comparable to extended cholecystectomy for patients with T1b GBCA. More extensive resections did not improve the prognosis.
Exploring the feasibility and effectiveness of a naturalistic family centered intervention to enhance early interactions in toddlers with Down syndrome
(2025) Mendoza-García, Ana; Aparicio, Andrés; Arango, Paulina Sofía; Tenorio, Marcela
This study analyses the feasibility and effectiveness of BabyMICARE, a manualised intervention programme aimed at improving the interactions between caregivers and infants and toddlers with Down syndrome. The programme’s goal is to enhance caregivers’ sensitivity and reduce directivity during early interactions, particularly during play and daily routines. A pre-test and post-test design was used with 40 dyads of infants with Down syndrome and their caregivers, who were divided into a control group (n = 20) and an intervention group (n = 20), based on baseline scores in key interaction subscales. Sessions were conducted over 10 weeks by trained psychologists. Parent-infant interaction was assessed using the MACI coding system, which measures aspects such as sensitive responsiveness, directivity and the level of reciprocity between the parent and the child. The programme showed high feasibility, with a 100% attendance rate but some rescheduling. Caregivers evaluated it positively. The intervention group demonstrated significant improvements in five of eight MACI scales, particularly in sensitive responsiveness and nondirectiveness, while no changes were observed in the control group.
The results suggest that BabyMICARE is a feasible and effective intervention for promoting more responsive, less directive interactions, which may be crucial in fostering children’s development.
Your baby has down syndrome: a reflexive thematic analysis of breaking the news to parents
(2025) Tenorio, Marcela; Sagner-Tapia, Johanna; Garibaldi, Renata; Totsika, Vaso
The communication of a Down syndrome diagnosis to mothers is a pivotal moment that can impact their emotional well-being and the subsequent care for their child. This study aimed to explore maternal experiences with receiving a Down syndrome diagnosis. A total of 40 mothers participated, 42.5% received a prenatal diagnosis, 17.5% received the diagnosis during labor and delivery, and 40% received the information at the early postnatal period. Through reflexive thematic analysis, four key themes emerged: (1) About Who and How the News Was Delivered (2), About When the News Was Delivered (3), On Where the News Should Be Delivered (4), parents’ positive experiences emerging from this, predominantly, negative episode. Our findings emphasize the need for improved training for healthcare professionals in delivering sensitive diagnoses, with an emphasis on empathy, accurate information, and support resources for families.
Análisis epidemiológico de hospitalizaciones por fracturas de columna cervical: estudio descriptivo de tendencias temporales 2021-2024
(2026) Sotomayor, Sebastián; Sotomayor, Juan
Introducción: Las fracturas de columna cervical constituyen un problema relevante de trauma por su asociación con lesión neurológica, necesidad de hospitalización y utilización de recursos. Objetivo: Describir la carga hospitalaria por fracturas de columna cervical en Chile durante 2021-2024, según sexo, grupo etario, diagnóstico y estadía. Metodología: Estudio observacional, descriptivo y retrospectivo basado en registros secundarios agregados de egresos/hospitalizaciones del Departamento de Estadísticas e Información de Salud. Se analizaron frecuencias, promedios de días de estadía y tendencia temporal mediante modelo de Poisson. Resultado: Se registraron 2018 hospitalizaciones. Predominó el sexo masculino (70,7%; razón 2,41:1). El número anual aumentó de 454 (2021) a 560 (2024), con una razón de tasas de incidencia de 1,064 (p=0,0019). El grupo etario más afectado fue de 20-44 años (39,3%). El diagnóstico más frecuente fue “Fractura de otras vértebras cervicales especificadas” (29,2%). El promedio de estadía fue 14,1 días. Discusión: El predominio masculino, la concentración de hospitalizaciones en adultos de edad productiva y la tendencia creciente observada durante el período estudiado evidencian una importante carga asistencial para el sistema de salud, destacando la necesidad de fortalecer las estrategias de prevención y vigilancia epidemiológica. Conclusión: Las hospitalizaciones por fracturas de columna cervical en Chile mostraron una tendencia creciente durante 2021–2024, con predominio del sexo masculino y mayor frecuencia en adultos de 20 a 44 años. Estos hallazgos aportan evidencia epidemiológica nacional útil para la planificación de recursos sanitarios y el diseño de estrategias preventivas dirigidas a los grupos de mayor riesgo.
Introduction: Cervical spine fractures represent a major traumatic injury due to their association with neurological damage, the need for hospitalization, and substantial healthcare resource utilization. Objective: To describe the hospital burden of cervical spine fractures in Chile from 2021 to 2024 according to sex, age group, diagnosis, and length of hospital stay. Methodology: An observational, descriptive, and retrospective study was conducted using aggregated secondary hospital discharge records from Department of Health Statistics and Information. Frequencies, mean length of hospital stay, and temporal trends were analyzed using a Poisson regression model. Result: A total of 2.018 hospitalizations were recorded. Males accounted for 70,7% of cases (male-to-female ratio: 2,41:1). Annual hospitalizations increased from 454 in 2021 to 560 in 2024, with an incidence rate ratio of 1,064 (p=0,0019). The most affected age group was 20-44 years (39,3%). The most frequent diagnosis was "Fracture of other specified cervical vertebrae" (29,2%). The mean length of hospital stay was 14,1 days. Discussion: The predominance of male patients, the concentration of hospitalizations among working-age adults, and the increasing trend observed during the study period indicate a substantial burden on the healthcare system, highlighting the need to strengthen prevention strategies and epidemiological surveillance. Conclusion: Hospitalizations due to cervical spine fractures in Chile showed an increasing trend between 2021 and 2024, with a predominance of male patients and the highest frequency among adults aged 20-44 years. These findings provide national epidemiological evidence to support healthcare resource planning and the development of targeted prevention strategies for high-risk populations.
Implementación de un modelo in-vitro de ciclos erosivoabrasivos para el estudio del desgaste dental erosivo.
(2025) Cabello, Rodrigo; Díaz, Mario; Gómez, Valeria
Objetivo:
Generar lesiones erosivas artificiales en bloques de esmalte dental humano por medio de la implementación de un modelo de ciclos erosivo-abrasivos utilizando pasta dental sin fluoruros in-vitro.
Materiales y Métodos:
Se prepararon 8 muestras de esmalte dental humano y se sometieron cíclicamente a seis ataques erosivos diarios mediante la inmersión de 2 minutos en ácido cítrico al 0,5%, cuyo pH=2,4 alternando con la exposición a saliva artificial durante una hora, proceso que fue realizado durante diez días. Adicionalmente, las muestras fueron expuestas a dos cepillados diarios con una pasta de dientes sin flúor. La cuantificación de la pérdida de tejido mineral se realizó con microtomografía computarizada y perfilometría de contacto.
Resultados:
Luego de la aplicación del modelo, se visualiza la generación de lesiones erosivas cuya media de pérdida de tejido fue de 18,08 μm (DE 4,71 μm) observada en Micro-CT y 21,9 μm (DE 2,59 µm) cuantificada utilizando perfilometría de contacto.
Conclusiones:
Los resultados obtenidos demuestran la efectividad del modelo para generar lesiones erosivas artificiales in-vitro.
Objective:
To generate artificial erosive lesions in human dental enamel samples by implementing an erosive-abrasive cycle model using fluoride-free toothpaste in-vitro.
Materials and Methods:
Eight human dental enamel samples were prepared and subjected to six daily erosive challenges. These challenges involved immersing the samples in 0.5% citric acid at pH 2.4 for 2 minutes, alternating with exposure to artificial saliva for one hour, over a period of ten days. Additionally, the samples were subjected to two daily brushings with fluoride-free toothpaste. Tissue loss was measured using micro-computed tomography (Micro-CT) and contact stylus profilometry.
Results:
Following the application of the model, the generation of erosive lesions was observed, with a mean tissue loss of 18.08 μm (SD 4.71 µm) as seen in Micro-CT and 21.9 μm (SD 2.59 µm) as quantified using contact profilometry.
Conclusions:
The results demonstrate the effectiveness of the model in generating artificial erosive lesions in-vitro.
La taxatividad legal de las causales de implicancia y recusación y el control de la idoneidad moral del juez
(2025) Jenkins Peña y Lillo, Gaspar; Miranda Reyes, Diego
El presente trabajo examina el derecho de las partes de un juicio a presentar una implicancia o recusación contra el juez, como un mecanismo para garantizar el derecho a un juez independiente, imparcial e idóneo, integrante del contenido sustantivo del debido proceso. Este análisis constata la problemática derivada de la taxatividad de las hipótesis legales que permiten invocar una implicancia y recusación, que limita la posibilidad de señalar situaciones distintas que también podrían evidenciar la parcialidad o falta de idoneidad del juez.
Finalmente, se consideran distintas alternativas para lograr proponer posibles soluciones.
El principio de legalidad impositiva, interpretación administrativa y cambio de criterios administrativos: Un análisis jurisprudencial
(2025) Céspedes Proto, Rodrigo; García Escobar, Jaime
Se analiza una sentencia de protección de la Corte de Santiago, acción interpuesta por Watt's S.A. contra el SII, a ráz de una Circular que modificó el criterio sobre la aplicación de un impuesto adicional a ciertos productos. El fallo aborda temas fundamentales del derecho tributario y administrativo. La Corte acogió el recurso por estimar que la nueva interpretación excedía las facultades del SII y vulneraba garantías constitucionales.
Rol de la biopsia de linfonodo centinela en el manejo del carcinoma escamoso cutáneo de cabeza y cuello
(2025) Quezada, Andrés; Molina, Luis; Araya, Cristóbal; Chang, Mauricio; Valdes, Fabio; Tapia, Mario
El cáncer de piel de tipo no melanoma corresponde al cáncer más común a nivel mundial. Dentro de ellos, el carcinoma escamoso cutáneo (CEC) representa aproximadamente el 20% de los casos, con una incidencia en aumento y mayor afectación en áreas fotoexpuestas de la cabeza y el cuello. Aunque la mayoría de los casos se trata con éxito mediante cirugía, existe un grupo de pacientes que enfrenta un mayor riesgo de recurrencia, metástasis y mortalidad. La presencia de metástasis linfática reduce significativamente la supervivencia, lo que ha impulsado el desarrollo de estrategias de evaluación y manejo en pacientes sin evidencia de compromiso linfonodal. Estas incluyen la identificación de grupos de alto riesgo, el estudio imagenológico, la observación clínica y la disección cervical electiva. En los últimos años, se ha investigado la utilidad de la biopsia de linfonodo centinela (BLC) en el manejo del CEC en cabeza y cuello. Sin embargo, actualmente no existe evidencia suficiente que permita establecer su uso generalizado. Este artículo revisa la literatura actual con objeto de ayudar a los equipos de cirugía oncológica de cabeza y cuello en su toma de decisiones.
Non-melanoma skin cancer is the most common cancer worldwide. Among them, cutaneous squamous cell carcinoma (SCC) represents approximately 20% of cases, with an increasing incidence and greater impact on sun-exposed areas of the head and neck. While most cases are successfully treated with surgery, a subset of patients faces higher risks of recurrence, metastasis, and mortality. The presence of nodal metastasis significantly reduces survival, prompting the development of various management strategies for patients without clinical evidence of nodal involvement. These strategies include identifying high-risk groups, imaging evaluation, clinical observation, and elective cervical dissection. In recent years, the utility of sentinel lymph node biopsy (SLNB) has been investigated in managing SCC in the head and neck. However, there is insufficient evidence to establish its widespread use. This article reviews the current literature to assist head and neck surgical oncology teams in decision-making.
La intervención de terceros cotitulares de la acción de interés colectivo y difuso
(2025) Carrasco Poblete, Jaime; Contardo-González, Juan Ignacio
La investigación busca reflexionar sobre la intervención de terceros cotitulares de la acción colectiva o difusa en el ámbito del consumo y establecer según la dogmática procesal cómo deben comparecer en un proceso pendiente. Para ello, se analiza la legitimación activa de los sujetos que pueden ejercer acciones de interés colectivo y difuso en el ámbito del consumo, se objetan las formas tradicionales de intervención de terceros que la jurisprudencia ha aplicado al tercero
cotitular de estas acciones, se postula que la figura correcta es la del tercero adhesivo litisconsorcial y se señalan las principales características de ese tipo de intervención.
Análisis comparativo de la desinformación verificada por plataformas de chequeo durante los plebiscitos constituyentes 2022 y 2023 en Chile
(2025) Labrador, María José; Jaramillo Castro, Oscar; Sibrian, Nairbis
El presente estudio analiza los desórdenes informativos y las metodologías de verificación utilizadas por las plataformas chilenas Mala Espina Check y Fact Check.CL durante los plebiscitos constitucionales de 2022 y 2023. Se empleó un enfoque cuanti-tativo-comparativo y la técnica de análisis de contenido. La muestra consistió en 237 casos de desinformación verificados por ambas plataformas. Los resultados indican que la desinformación en temas electorales circula principalmente en redes sociales y, en menor medida, en medios de comunicación. Estos contenidos se originan en fuentes difusas o son compartidos por personalidades públicas y se presentan en formato de imagen. Se clasifican mayoritariamente como contenido engañoso e impostor, con una intencionalidad media. Las plataformas verificaron estos casos mediante la búsqueda inversa de imágenes y la revisión de documentos oficiales. Las conclu-siones sugieren que los procesos políticos son los principales focos de desinformación intencionada, proveniente de fuentes difusas. El estudio también revela la necesidad de implementar metodologías complementarias para una selección, caracterización y clasificación más rigurosa de la desinformación. Esto permitirá análisis más complejos y detallados en futuros estudios sobre contextos electorales
Unequal expression: Social position modulates APOE genotype risk of dementia
(2025) Aravena, José M.; Chen, Xi; Levy, Becca R.
Background
Although social position plays a pivotal role in cognitive aging, most dementia prevention strategies and risk prediction models continue to emphasize biomedical and genetic factors (particularly APOE status). This disconnect raises critical questions about how social environments may shape the effect of genetic risk on dementia. We examined how APOE alleles interact with social adversity to determine dementia risk.
Methods
We conducted an observational analysis using two large cohort studies—the Health and Retirement Study (HRS) and the English Longitudinal Study of Ageing (ELSA)—including individuals aged 55 years or older without dementia at baseline. A social adversity index was constructed based on the five domains of social determinants of health outlined in the Healthy People 2030 framework: education access, economic stability, healthcare quality, neighborhood environment, and social context. Participants were classified as having low (APOE-ε2), intermediate (APOE-ε3/ε3), or high (APOE-ε4) genetic risk of dementia. Dementia was ascertained via clinical diagnosis, cognitive testing, or validated caregiver report. Cox proportional hazards models were used in each cohort, and estimates were pooled using random-effects adjusting for covariates.
Results
A total of 9,849 participants (HRS = 5,797; ELSA = 4,052) were followed for up to 12 years. Genetic effects were most pronounced among individuals with social advantage (reference: APOE-ε3/ε3 with social advantage; APOE-ε2 HR = 0.67, 95%CI = 0.48–0.93; APOE-ε4 HR = 1.68, 95%CI = 1.37–2.06). In contrast, those experiencing high social adversity had elevated dementia risk regardless of genotype (reference: APOE-ε3/ε3 with social advantage; APOE-ε2 HR = 3.26, 95%CI = 2.06–5.16; APOE-ε3/ε3 HR = 3.12, 95%CI = 2.47–3.95; APOE-ε4 HR = 3.21, 95%CI = 2.34–4.41). Notably, individuals with high genetic risk but social advantage had a lower dementia risk than those with low genetic risk but high social adversity.
Conclusions
The influence of genetic risk on dementia appears shaped by social position. Addressing social adversity may reduce dementia risk across genotypes and enhance equity in dementia prevention strategies.
Incorporación del enfoque de derechos en la gestión local migratoria en Chile
(2025) Colmenares Mejías, Neida Josefina; Sibrian, Nairbis; Gissi Barbieri, Nicolás
In Chile, migrants constitute 10% of the population with 75% residing just 14% of the country’s municipalities. This high territorial concentration of migration is a distinctive feature of the Chilean context; however, research on the subject remains scarce and there is no national policy that effectively guides public migration management at the territorial level. For this reason, the article contributes to determining the characteristics of Chilean local migration management and its possible rights-based approach from the perspective of public officials who worked directly with the migrant and refugee population between 2023 and 2024. An exploratory and descriptive research design with a quantitative approach was employed. Data were collected through a survey in which 465 civil servants from 158 municipalities participated. The results show that Venezuelan, Colombian and Haitian women are the ones who request social assistance the most and that municipalities with larger migrant populations experience greater demand for regularization and protection against gender-based violence. However, municipal service provision remains fragmented and insufficiently coordinated with the central government. A gender approach implementation index was developed and an appraisal of the implementation level of the rights-based approach was conducted, obtaining average levels with territorial asymmetries. Messages from the media and opposition politicians emerge as the main obstacle in local work with the migrant population, and the main challenges are training and strengthening municipal institutions.