ABSTRACT
Surface-modified PAMAM dendrimers have important applications in drug delivery, yet a gap remains about the role that surface functionalization plays on their cell internalization capacity. We examined the cell internalization kinetics of PAMAM dendrimers that were surface-modified with acetyl, folate and poly(ethylene glycol), as model functional groups differing in size, charge, and chemical functionality. Dendrimers with 25% functionalization were internalized by HEK cells, but with slower rates and lower maximum uptakes than the native dendrimer between 1-6 h of incubation. Dendrimers with 50% functionalization exhibited negligible internalization capacities at all incubation times. Molecular dynamics simulations revealed that the solvent accessibility of the cationic surface charges is a key factor affecting cell internalization, unlike the total charge, functionality or size of surface-modified PAMAM dendrimers. These findings provide valuable insights to assist the design of PAMAM-based systems for drug delivery applications.
Subject(s)
Dendrimers , Dendrimers/chemistry , Drug Delivery Systems , Polyethylene Glycols/chemistry , SolventsABSTRACT
Introducción: El ambiente educacional (AE) se define como todo lo que rodea al estudiante en la academia. Conocer la percepción de los estudiantes sobre el AE es relevante para crear planes de estudios de calidad. El AE puede medirse con distintos instrumentos, uno de los cuales es el Dundee Ready Education Environment Measure (DREEM). En Odontología, este aspecto tiene un sentido especial, porque sus estudiantes se enfrentan a un AE complejo que varía durante los años. Por todo lo anterior, el objetivo de esta investigación fue identificar, basándonos en la bibliografía, las áreas más problemáticas del ambiente educacional según la percepción de los estudiantes de Odontología según el cuestionario DREEM.Materiales y métodos.Se realizó una revisión bibliográfica, con estrategias de búsquedas relacionadas con DREEM y educación dental en las bases de datos PubMed, EBSCO, Scielo y Web of Science, en el período comprendido entre enero de 2010 y octubre de 2020.Resultados.De 305 estudios, 11 cumplieron con los criterios de elegibilidad y fueron seleccionados para su análisis. La totalidad de los estudios examinó el AE con el cuestionario DREEM en estudiantes de Odontología de pregrado. De esto se extrajo que los ítems más problemáticos (puntuación menor de 2) fueron los ítems 3, 4, 42, 48, 25 y 9.Conclusión.Los estudiantes percibieron como áreas problemáticas aspectos relacionados con el estrés académico, docentes y el método de enseñanza. Estas dificultades son comunes dentro de las facultades de Odontología y la bibliografía ha propuesto múltiples soluciones con el fin de mejorar el AE. (AU)
Introduction: The educational environment (AE) is defined as everything that surrounds the student in the academy. Knowing the perception of students about AE is relevant to create quality study plans, this can be measured with different instruments, one of them is the Dundee Ready Education Environment Measure (DREEM). In dentistry this aspect has a special meaning because its students face a complex AE that changes over the years. Therefore, the objective of this research was to identify, based on the literature, the most problematic areas of the AE according to the perception of dental students based on the DREEM questionnaire.Materials and methods.A bibliographic review was carried out, with search strategies related to DREEM and dental education in the PubMed, EBSCO, Scielo and Web of Science databases; with articles published from January 2010 to October 2020.Results.Of 305 studies, 11 fulfilled the eligibility criteria and were selected for analysis. All the studies examined EA with the DREEM questionnaire in undergraduate dental students. From this it was extracted that the most problematic items (score less than 2) were items 3,4,42,48,25 and 9.Conclusion.Students perceived aspects related to academic stress, teachers and the teaching method as problem areas. These difficulties are common in dental schools and the literature has proposed multiple solutions in order to improve EA. (AU)
