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Iron-Reduced Graphene Oxide Core-Shell Micromotors Designed for Magnetic Guidance and Photothermal Therapy under Second Near-Infrared Light
No full textCore-shell micro/nanomotors have garnered significant interest in biomedicine owing to their versatile task-performing capabilities. However, their effectiveness for photothermal therapy (PTT) still faces challenges because of their poor tumor accumulation, lower light-to-heat conversion, and due to the limited penetration of near-infrared (NIR) light. In this study, we present a novel core-shell micromotor that combines magnetic and photothermal properties. It is synthesized via the template-assisted electrodeposition of iron (Fe) and reduced graphene oxide (rGO) on a microtubular pore-shaped membrane. The resulting Fe-rGO micromotor consists of a core of oval-shaped zero-valent iron nanoparticles with large magnetization. At the same time, the outer layer has a uniform reduced graphene oxide (rGO) topography. Combined, these Fe-rGO core-shell micromotors respond to magnetic forces and near-infrared (NIR) light (1064 nm), achieving a remarkable photothermal conversion efficiency of 78% at a concentration of 434 µg mL-1. They can also carry doxorubicin (DOX) and rapidly release it upon NIR irradiation. Additionally, preliminary results regarding the biocompatibility of these micromotors through in vitro tests on a 3D breast cancer model demonstrate low cytotoxicity and strong accumulation. These promising results suggest that such Fe-rGO core-shell micromotors could hold great potential for combined photothermal therapy.Versión Publicad
Manual de Neurología: para el interno y médico general
Get PDFEn 2019, a partir de un proyecto postulado por un estudiante, nace este manual como un apoyo a la formación en neurología que se imparte en el pregrado de medicina. De esta manera, junto al grupo de alumnos-ayudantes de la unidad de neurología se inicia el desarrollo de los primeros capítulos. Para 2023 se decide formalizar el manual, incluyendo a los médicos del postgrado en Neurología Adultos de la misma facultad, formando una alianza que abarca desde estudiantes de pregrado hasta neurólogos subespecialistas, con lo cual el manual de neurología adquiere un nuevo impulso que nos lleva a la selección y publicación de 9 capítulos cuyo objetivo es transmitir los conceptos esenciales de los síndromes y patologías abarcados en éstos, adaptándolos a la realidad nacional.https://medicina.udd.cl/files/2024/10/2024-07-31-manual-neurologia.pd
Advances in machine learning for tumour classification in cancer of unknown primary: A mini-review
Get PDFCancers of unknown primary (CUP) are a heterogeneous group of aggressive metastatic cancers where standardised diagnostic techniques fail to identify the organ where it originated, resulting in a poor prognosis and resistance to treatment. Recent advances in large-scale sequencing techniques have enabled the identification of mutational signatures specific to particular tumour subtypes, even from liquid biopsy samples such as blood. This breakthrough paves the way for the development of new cost-effective diagnostic strategies. This mini-review explores recent advancements in Machine Learning (ML) and its application to tumour classification methods for CUP patients, identifying its weaknesses and strengths when classifying the tumour type. In the era of multi-omics, integrating several sources of information (e.g., imaging, molecular biomarkers, and family history) requires important theoretical advancements: increasing the dimensionality of the problem can result in lowering the predictive accuracy and robustness when data is scarce. Here, we review and discuss different architectures and strategies for incorporating cutting-edge machine learning into CUP diagnosis, aiming to bridge the gap between theory and clinical practice.Versión Aceptad
Food insecurity and sociodemographic factors in Latin America during the COVID-19 pandemic
Get PDFObjective. To understand the association of food insecurity with sociodemographic factors in a sample population in Latin America during the COVID-19 pandemic.
Methods. This was a multicenter cross-sectional study conducted in 10 countries in Latin America using an online survey through various digital platforms from October 14, 2020 to February 15, 2021. Statistical analysis of data was performed by applying descriptive statistics, chi-square test, and logistic regression analysis.
Results. Of a total of 6 357 surveys, 58.2% of respondents experienced food security, 29.3% were slightly food insecure, 9.2% were moderately food insecure, and 3.3% were severely food insecure. Concerning the association food insecurity and sociodemographic variables, there is a significant association in the variables studied, including area of residence, education level, occupation, number of persons in the household, house hold with children younger than 10 years of age, and socioeconomic level.
Conclusions. These findings indicate that sociodemographic factors associated with food insecurity during the COVID-19 pandemic in Latin America were rural residence; complete and incomplete basic and secondary schooling; occupation (homemaker, unemployed, and self-employed); low, medium-low, and medium socioeconomic level; household with more than four persons; and household with children younger than 10 years of age.Versión publicad
Molecular Analysis of PIK3CA in Metastatic Hormone Receptor-Positive Breast Cancer in Chile: Clinical and Pathological Insights
Get PDFBreast cancer is the most common cancer among women and a leading cause of cancerrelated deaths. PIK3CA gene mutations, which are often present in advanced HR+ breast cancer, can be targeted by alpelisib. However, data on PIK3CA mutations in Chile are limited. Here, we aim to assess the mutational status of PIK3CA in metastatic breast cancer tissues from Chilean patients and describe their clinicopathological characteristics and survival outcomes. We analyzed 102 formalinfixed, paraffin-embedded metastatic breast cancer samples from 96 patients diagnosed at three Chilean hospitals between 2007 and 2023. PIK3CA mutations were identified using targeted sequencing, and clinicopathological data were collected. We evaluated associations between mutational status,
clinicopathological features, and survival. The median age at diagnosis was 56 years. The most common metastatic sites were liver (29.4%), bone (17.6%), and lung/pleura (16.7%). Most patients
were HR+ HER2− (83.3%), with 57.3% showing HER2-low status. PIK3CA mutations were present in 40.6% of patients, mainly in exons 7, 9, and 20. No significant associations were found between
PIK3CA mutations and clinicopathological characteristics or survival. Our study reveals a high frequency of PIK3CA mutations in HR+ metastatic breast cancer, consistent with global data. The
majority of mutations are targetable with alpelisib. The proportion of HER2-low status patients suggests potential benefits from novel HER2-targeted therapies. These findings highlight the need
for routine molecular diagnostics in Chile to improve personalized treatment and address economic and access challenges.Versión Publicad
Ma.Pa: Fortaleciendo el vínculo de la pareja en el tránsito del embarazo y postparto
No full textMemoria presentada a la Facultad de Diseño de la Universidad del Desarrollo para optar al Título Profesional de DiseñadorLa llegada del primer hijo es a lo largo del embarazo, un período difícil y desafiante para las parejas.
A lo largo del trabajo de parto y el posparto, ambos deben adaptarse a la nueva realidad de tener un recién nacido. Esta transición viene con desafíos emocionales, psicológicos y sociales para ambos miembros de la pareja. La experiencia de crianza enfrenta desafíos prácticos y emocionales a medida que aprenden a experimentar juntos esa nueva fase. Sin embargo, en el transcurso del parto, el foco está en la madre y el bebé, y la integración de la pareja puede retrasarse. Esto logra causar sentimientos de aislamiento, inseguridad, ansiedad y estrés en el hombre. Por otro lado, la mujer puede sentirse sola, sin apoyo de su pareja, agotada y frustrada, lo que puede generar distanciamiento en la relación.
Este proyecto busca abordar el tema del vínculo de pareja en el embarazo y el postparto, enfocado en la llegada del primer hijo, ya que este puede redefinir la relación entre la pareja, aspecto que a menudo se pasa por alto. “Ma.Pa” busca abordar estos desafíos para que a través del diseño se pueda fortalecer
la relación a través de la entrega de información y el manejo de la comunicación para desarrollar una base sólida para la familia en crecimiento
Risk Factors for Failure of Non-operative Management in Isolated Unilateral Non-displaced Facet Fractures of the Subaxial Cervical Spine: Systematic Review and Meta-Analysis
Get PDFStudy Design: systematic review.Objective: To evaluate risk factors associated with failure of non-operative management of isolated unilateral facet fractures ofthe subaxial cervical spine in neurologically intact patients.Methods: A systematic review of the PubMed, Embase, LILACS, and Cochrane Library databases was conducted in order todetermine risk factors associated with failure of non-operative management in isolated unilateral facet fractures of the subaxialcervical spine without facet and/or vertebral displacement, in neurologically intact patients. Our research was in line with thePRISMA Statement and registered on PROSPERO (CRD42023405699).Results: A total of 1639 studies were identified through a database search on May 5, 2023. In total, 7 studies from the databaseswere included, along with 1 study found through a manual citation search. The evidence showed high clinical heterogeneity, aserious risk of bias according to the ROBINS-I tool, and a predominance of retrospective cohort studies. In comparison to lesscomplex facet fractures, lateral floating mass fractures were found to have 5.41 times higher odds of failure of non-operativemanagement (OR = 5.41; 95% CI = 1.32, 22.19). We calculated the potential association between lower absolute fracture heightand non-operative treatment success [Fracture height (percentage) Mean Difference = 17.51 ( 28.22, 6.79 95% CI); Absolute height Mean Difference: 0.46 ( 0.60, 0.31 95% CI)]. Other risk factors were not included in the meta-analysis dueto lack of data. The level of certainty was rated as “very low”.Conclusions: Lateral floating mass cervical facet fractures and larger fracture fragment size (measured either in absolute termsor as a percentage) are significant risk factors for failure of non-operative treatment.Versión publicad
Constitutional fiscal stability rules : comparative experiences
Get PDFEl artículo analiza críticamente la consagración constitucional de reglas de responsabilidad fiscal en cuatro países: Suiza, Alemania, España e Italia.
Se examinan los textos constitucionales, así como las apreciaciones doctrinarias.Se discuten algunas de sus complejidades recurrentes, tales como: flexibilizaciones, excepciones, el papel del Parlamento y soluciones frente a incumplimientos. Se concluye formulando una serie de recomendaciones para Chile, fundamentadas en ciertos supuestos que se explicitan.Versión publicad
Construcción y validación guía para las buenas prácticas de comunicación de riesgo durante crisis sanitarias
Get PDFINTRODUCCIÓN. La pandemia COVID-19 evidenció la necesidad de contar con estrategias de comunicación de riesgo efectivas y contextualizadas al territorio, para la toma de decisión informada de la comunidad.
OBJETIVO. describir la construcción y validación por expertos de una Guía de Buenas Prácticas para Comunicación de Riesgo durante una crisis sanitaria (GBP-CR) en el contexto chileno.
MATERIAL Y MÉTODOS. Estudio multi método y de validez de constructo para los elementos de evaluación de la guía.
RESULTADOS. Se construyó una GBP-CR que aborda contenidos teóricos sobre comunicación de riesgo (CR), institucionalización de la estrategia, su enfoque y análisis del contexto de implementación. Incluye recomendaciones para construir, transmitir y evaluar el mensaje para una CR efectiva y rúbricas para valorar tres aspectos centrales de los comunicados.
CONCLUSIÓN. Se construyó la primera Guía de Buenas Prácticas para la Comunicación de Riesgo durante una crisis sanitaria basada en evidencia y ajustada a la realidad local.
INTRODUCTION. The COVID-19 pandemic evidenced the need for effective risk communication strategies that promote informed community decision making.
OBJECTIVE. to describe the construction and validation process by experts of a Guideline for Best Practice for Risk Communication during a health crisis (GBP-RC) in the Chilean context.
METHODS. A multi methods study and validity study was carried out for the evaluation elements of the guideline.
RESULTS. A GBP-RC was built that addresses central theoretical contents on risk communication (RC), ways of institutionalizing the strategy, its approach, and analysis of the implementation context. It includes recommendations on how to build, transmit and evaluate the message for an effective RC and rubrics to assess three central aspects of the CONCLUSION. The first Guideline for Best Practices for Risk Communication was built during a health crisis based on evidence and adjusted to the local realityVersión Aceptad
Barreras para una alimentación saludable: un análisis cualitativo de las semánticas emergentes en las comunidades escolares de Ciudad Sur
Get PDFObjetivo: Identificar las percepciones de padres, madres y apoderados, profesionales de establecimientos educacionales, funcionarios municipales, y feriantes pertenecientes a la zona sur de Santiago de Chile, respecto a las barreras y limitaciones de la puesta en práctica de una alimentación saludable en el ambiente alimentario escolar.
Método: Se realizaron seis grupos focales agrupando a 50 actores claves vinculados a los establecimientos educacionales de Ciudad Sur utilizando una muestra no probabilística. Se aplicó un análisis de contenido mediante la técnica de codificación temática buscando relevar los universos semánticos emergentes.
Resultados: Se identificaron nueve barreras, o semánticas, que caracterizan limitantes a la realización de la alimentación saludable en los entornos escolares desde la perspectiva de los participantes: la familia, kioscos escolares, la salida de los establecimientos escolares, gusto, determinantes socioeconómicos, política pública, falta de conocimiento, publicidad y disponibilidad de productos sin sellos.
Conclusiones: Las limitaciones asociadas al ambiente alimentario doméstico tienen una representación significativamente alta (47,9%) y contienen un carácter de responsabilización individual en su enunciación. Esta cultura explicativa es opuesta a la evidencia científica y académica respecto al funcionamiento de la conducta alimentaria, y a la centralidad de los ambientes alimentarios respecto a la facilitación u obstaculización del consumo de alimentos saludables o adecuados.Publicad