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ADAR-Mediated A>I(G) RNA Editing in the Genotoxic Drug Response of Breast Cancer
Get PDFEpitranscriptomics is a field that delves into post-transcriptional changes. Among these modifications, the conversion of adenosine to inosine, traduced as guanosine (A>I(G)), is one of the known RNA-editing mechanisms, catalyzed by ADARs. This type of RNA editing is the most common type of editing in mammals and contributes to biological diversity. Disruption in the A>I(G) RNA-editing balance has been linked to diseases, including several types of cancer. Drug resistance in patients with cancer represents a significant public health concern, contributing to increased mortality rates resulting from therapy non-responsiveness and disease progression, representing the greatest challenge for researchers in this field. The A>I(G) RNA editing is involved in several mechanisms over the immunotherapy and genotoxic drug response and drug resistance. This review investigates the relationship between ADAR1 and specific A>I(G) RNA-edited sites, focusing particularly on breast cancer, and the impact of these sites on DNA damage repair and the immune response over anti-cancer therapy. We address the underlying mechanisms, bioinformatics, and in vitro strategies for the identification and validation of A>I(G) RNA-edited sites. We gathered databases related to A>I(G) RNA editing and cancer and discussed the potential clinical and research implications of understanding A>I(G) RNA-editing patterns. Understanding the intricate role of ADAR1-mediated A>I(G) RNA editing in breast cancer holds significant promise for the development of personalized treatment approaches tailored to individual patients' A>I(G) RNA-editing profiles.Versión Publicad
Deep phenotyping of post-infectious myalgic encephalomyelitis/chronic fatigue syndrome
Get PDFMalik, Nasir; Mammen, Andrew; McCulloch, John; McGurrin, Patrick; Milner, Joshua; Moaddel, Ruin; Mueller, Geoffrey; Mukherjee, Amrita; Muñoz, Sandra; Norato, Gina; Pak, Katherine; Pinal, Lago; Popa,Traian; N Sack, Michael; Safavi, Farinaz; Saligan, Leorey; Sellers, Brian; Sinclair, Stephen; Smith, Bryan; Snow, Joseph; Solin, Stacey; Stussman, Barbara; Trinchieri, Giorgio; Turner, Sara, Vetter, Stephenie; Vizioli, Carlotta, Williams, Ashley; Yang, Shanna; Center for Human Immunology, Autoimmunity, and Inflammation (CHI) Consortium; Avindra Nath.Post-infectious myalgic encephalomyelitis/chronic fatigue syndrome (PI-ME/CFS) is a disabling disorder, yet the clinical phenotype is poorly defined, the pathophysiology is unknown, and no disease-modifying treatments are available. We used rigorous criteria to recruit PI-ME/CFS participants with matched controls to conduct deep phenotyping. Among the many physical and cognitive complaints, one defining feature of PI-ME/CFS was an alteration of effort preference, rather than physical or central fatigue, due to dysfunction of integrative brain regions potentially associated with central catechol pathway dysregulation, with consequences on autonomic functioning and physical conditioning. Immune profiling suggested chronic antigenic stimulation with increase in naïve and decrease in switched memory B-cells. Alterations in gene expression profiles of peripheral blood mononuclear cells and metabolic pathways were consistent with cellular phenotypic studies and demonstrated differences according to sex. Together these clinical abnormalities and biomarker differences provide unique insight into the underlying pathophysiology of PI-ME/CFS, which may guide future intervention.Versión Aceptad
The Immunoregulatory and Regenerative Potential of Activated Human Stem Cell Secretome Mitigates Acute-on-Chronic Liver Failure in a Rat Mode
No full textAcute-on-chronic liver failure (ACLF) is a syndrome marked by sudden liver function decline and multiorgan failure, predominantly acute kidney injury (AKY), in patients with chronic liver disease. Unregulated inflammation is a hallmark of ACLF; however, the key drivers of ACLF are not fully understood. This study explores the therapeutic properties of human mesenchymal stem cell (MSC) secretome, particularly focusing on its enhanced anti-inflammatory and pro-regenerative properties after the in vitro preconditioning of the cells. We evaluated the efficacy of the systemic administration of MSC secretome in preventing liver failure and AKI in a rat ACLF model where chronic liver disease was induced using by the administration of porcine serum, followed by D-galN/LPS administration to induce acute failure. After ACLF induction, animals were treated with saline (ACLF group) or MSC-derived secretome (ACLF-secretome group). The study revealed that MSC-secretome administration strongly reduced liver histological damage in the ACLF group, which was correlated with higher hepatocyte proliferation, increased hepatic and systemic anti-inflammatory molecule levels, and reduced neutrophil and macrophage infiltration. Additionally, renal examination revealed that MSC-secretome treatment mitigated tubular injuries, reduced apoptosis, and downregulated injury markers. These improvements were linked to increased survival rates in the ACLF-secretome group, endorsing MSC secretomes as a promising therapy for multiorgan failure in ACLF.Versión Publicad
When another one bites the dust: Environmental impact of global copper demand on local communities in the Atacama mining hotspot as registered by tree rings
Get PDFAssessing the impact of mining activity on the availability of environmental pollutants is crucial for informing health policies in anticipation of future production scenarios of critical minerals essential for the transition to a net-zero carbon society. However, temporal and spatial monitoring is often sparse, and measurements may not extend far enough back in time. In this study, we utilize variations of chemical elements contained in tree-rings collected in local villages from an area heavily affected by copper mining in the Atacama Desert since the early 20th century to evaluate the temporal distribution of pollutants and their relationship with local drivers. By combining time-varying data on local drivers, such as copper production and the dry tailings deposit area, we show how the surge in copper production during the 1990s, fueled by trade liberalization and increased international demand, led to a significant increment in the availability of metal(loid)s related to mining activities on indigenous lands. Our findings suggest that the environmental legislation in Chile may be underestimating the environmental impact of tailing dams in neighboring populations, affecting the well-being of Indigenous Peoples from the Atacama mining hotspot region. We argue that future changes in production rates driven by international demand could have negative repercussions on the environment and local communities. Therefore, mining emissions and the management of tailing dams should be carefully considered to anticipate their potential negative effects on human and ecosystem health.Versión publicad
Copulation Call in Female Hamadryas Baboons (Papio hamadryas): Adaptive Function and Information Content
Get PDFThesis Project submitted to the Faculty of Government at Universidad del Desarrollo in partial fulfillment of the requirements for the degree of Doctor in Social Complexity SciencesIntroduction: In primates, copulation calls are vocalizations emitted by females at the end of copulation, being common in promiscuous species organized in multi-male, multi-female groups.
These calls are thought to increase male competition for access to females, enhancing either male guarding or sperm competition around ovulation, which could respectively increase or confuse paternity certainty and reduce the risk of infanticide. Female hamadryas baboons also produce these calls. However, this species is organized in one-male units, where leader males sexually monopolize the females in their units, resulting in high paternity certainty. Therefore, these vocalizations appear to provide no obvious benefit in hamadryas baboons regarding risk of infanticide, raising the question of their role in this species.
Objective: This study aims to investigate the adaptive function of copulation calls in hamadryas baboons by examining their use (chapter 2) and the information they convey (chapter 3). We propose that if these vocalizations increase male competition in other primate species, in hamadryas baboons, they might be related to the coercive takeovers of females, as this is the primary consequence of male competition.
Methods: This study was based on an observational design using behavioral sampling to collect data on copulations and their acoustic behavior in the Hamadryas baboon colony at Madrid Zoo during July and September 1999. Additionally, previous databases from the colony’s longitudinal study and grooming interaction records were included. Using these data, we analyzed the presence of copulation calls in each event, their acoustic structure, the male’s and female’s social status, the occurrence of ejaculation, the female’s reproductive status, the presence of related females in the unit, and female transfers to other units.
Results: We observed that copulation calls are more likely in peripheral females within large units and central females in small units, occurring more frequently when the male ejaculates and during female’s maximal sexual swelling. These vocalizations were also associated with an increased likelihood of females transferring to other units, although such transfers occurred only in females belonging to small units. On the other hand, no evidence was found that copulation calls convey nformation about the male’s or female’s social status, but they did convey information about male ejaculation. Furthermore, significant acoustic variability was observed among females.
Conclusion: We conclude that copulation calls in hamadryas baboons are used and contain information different from that observed in other primates with promiscuous mating systems, suggesting a potentially distinct adaptive role. The evidence indicates that these vocalizations might be primarily related to promoting female transfers to other units, where their reproductive success could be increased. However, due to the limitations of our study, definitive conclusions cannot be drawn, and we highlight the need for longitudinal studies with longer observation periods to better understand their function
Observatorio vulconológico Vultur Andino
No full textTesina presentada a la Facultad de Arquitectura y Arte de la Universidad del Desarrollo para optar al grado académico / título profesional de Arquitecta con mención en Innovación y Emprendimiento.Chile, ubicado en el cinturón de fuego del Pacífico, alberga una amplia cantidad de volcanes, siendo el segundo país con mayor número en el mundo. Sin embargo, actualmente solo cuenta con una entidad responsable del monitoreo volcánico; cuyo objetivo es pronosticar la actividad volcánica y de este modo alertar a las comunidades que habitan las áreas aledañas.
No obstante, no solo los seres humanos habitan estos terrenos volcánicos, también son hogar de una gran diversidad de especies, entre las cuales destaca el cóndor andino, único en su tipo capaz de adaptarse a tales condiciones extremas de altitud y terreno inestable.
De este modo se desarrolla un proceso que relaciona la arquitectura de alta montaña para el monitoreo volcánico, con las soluciones biológicas que entrega el cóndor para la adaptación a las condiciones naturales. Este proceso se logra mediante la biomimesis, un enfoque arquitectónico que busca resolver problemas humanos a través de estrategias biológicas.
Para lograrlo, se realiza un análisis a cabalidad de diversas variables del cóndor, incluyendo su comportamiento en el aire y en tierra, así como sus características biológicas. Estas se interpretan para obtener diferentes opciones de geometrización que brinden soluciones a la problemática abordada en esta investigación
Cohesión grupal en educación: intervención en aula de un 1° medio de un colegio particular subvencionado de la comuna de La Florida
Get PDFTrabajo de Grado presentado a la Facultad de Psicología de la Universidad del Desarrollo para optar al grado de Magíster en Psicología EducacionalEl presente trabajo expone una intervención en la baja cohesión grupal en un I° Medio de un colegio particular subvencionado de la comuna la Florida.
A través de la “Escala de Cohesión Social percibida en la escuela” adaptada para el grupo de estudio, y otros instrumentos de recogida de información se encontraron resultados que corroboraron la hipótesis inicial respecto a la baja cohesión de los estudiantes de I° Medio.
Según Cloete (2014) dentro de las dimensiones que sustentan la cohesión social se encuentran la confianza, participación, sentido de pertenencia y colaboración, siendo las dos últimas las más afectadas en el caso estudiado.
Entre los principales hallazgos se identificó la división del curso en grupos muy marcados, falta de colaboración entre ellos y de compromiso con las tareas comunes, así como también, escaso apoyo a los estudiantes participantes en las distintas actividades. Con relación al sentido de pertenencia, los estudiantes evidenciaron sentirse parte de su grupo de amigos, pero no cómodos ni parte importante del curso.
La intervención posterior se realizó a través de 2 talleres, de 3 sesiones de 45 minutos cada uno, abordándose en ellos las dimensiones más afectadas. El primero de ellos tuvo como objetivo “Desplegar acciones de colaboración con todos los integrantes del curso”, y el segundo “Acrecentar el sentido de pertenencia de los estudiantes con su curso”.
Ambos objetivos se lograron, lo que se verificó a través de encuestas aplicadas a los estudiantes al finalizar la intervención.
Se concluye que, acciones sencillas pero oportunas pueden ser el punto de partida para iniciar cambios en las actitudes y comportamientos de los estudiantes, y, que estas producen mejoras en la percepción de estos respecto de si mismos, mayor conciencia de sus fortalezas y debilidades, así como también mejor disposición para realizar actividades de manera compartida con sus pares. Sin embargo, para que estas acciones tengan un efecto a largo plazo, es necesario que el establecimiento educacional de continuidad a la intervención y desarrolle un plan de acción a largo plazo que permita que los progresos vistos se puedan consolidar
Impacts of a Large-Scale Parenting Program: Experimental Evidence from Chile
No full textThis paper presents results from a large-scale experimental evaluation of the impacts on parents and children of a national parenting program in Chile. The program is low cost: it lasts only for six to eight weeks, and it is administered to groups (of 8 to 12 parents) rather than individuals. It is implemented by the national health system, taking advantage of its existing physical infrastructure, and the deep staff knowledge about the constraints faced by parents and children in each location. We find that children whose parents are offered the opportunity to participate in this program experience increases in their vocabulary and socio-emotional development scores of 0.1 standard deviations (SD), which are mirrored by improvements in parenting behaviors and parenting beliefs of the same magnitude. These impacts are observed almost three years after the intervention ends, far outlasting its duration.Versión Publicad
Organizaciones de la sociedad civil en el contexto del Plan Nacional del Cáncer (PNC). Reporte abreviado de estudio: Percepciones de roles, barreras y oportunidades de acción para la participación en la toma de decisiones en salud
No full textEl presente documento resume los resultados obtenidos del estudio que tenía como propósito conocer la percepción del rol, barreras y oportunidades de participación de las organizaciones de la sociedad civil relacionadas al cáncer en Chile, inscritas y no inscritas en el registro nacional de organizaciones vinculadas a salud (Ley Ricarte Soto N°20850), en el marco de la propuesta de participación ciudadana del Plan Nacional del Cánce
Clinical and radiographic characterization of external root resorption
No full textINTRODUCCIÓN La siguiente revisión bibliográfica se realizó con el propósito de reconocer las características clínicas y radiográficas que deben ser evaluadas para el diagnóstico de las reabsorciones radiculares externas incluyendo también sus tratamientos.
METODOLOGÍA Se llevó a cabo una búsqueda en las bases de datos MEDLINE/PubMed, Cochrane Library y Google Scholar bajo el término external root resorption, incluyendo estudios experimentales y revisiones bibliográficas desde 2010 a 2022 en español e inglés, incluyendo finalmente 17 artículos.
RESULTADOS Los resultados obtenidos señalaron que cada tipo de reabsorción radicular externa presenta características clínicas específicas que las diferencian. Estas diferencias son: para la reabsorción externa inflamatoria la vitalidad pulpar negativa; para la reabsorción externa de reemplazo la ausencia de movilidad y percusión metálica; para la reabsorción externa cervical una coloración rosada de la corona; la reabsorción externa superficial no presenta ningún tipo de sintomatología clínica y la reabsorción de colapso apical transitorio presenta un cambio de coloración transitorio.
CONCLUSIÓN Las reabsorciones radiculares externas requieren un diagnóstico preciso y temprano. Se debe realizar un examen clínico con énfasis en sondaje, coloración, movilidad y pruebas de vitalidadVersión aceptad