Factors affecting students' perception of flipped learning over time in a teacher training program.

The flipped learning methodology could play a key role in teacher training, as it exposes future teachers to experience this active methodology as students. With the purpose of shedding light on how students' perceptions may vary over time and how they can be related to the improvement of the flipped learning methodology, our study explores different factors in an eight-year period. Specifically, we analyse teaching performance considering data on students' perceptions from the 2015-2016 academic year to 2022-2023 of a course embedded within a master s degree in teacher training in Spain. Once future teachers had experienced flipped learning as students, a sample of 338 completed a survey regarding their perceptions of the flipped classroom approach and the instructor role. In our study, the more experienced the instructor, the better perception the students showed on both the flipped learning methodology and the performance of their teacher. In particular, we found that future teachers had (i) a good or very good opinion about flipped learning, regardless of their gender (ii) a more positive perception about flipped learning, teaching performance and course development in the last five academic years, (iii) no remarkable differences between study specialisations in those last academic years, and (iv) a better opinion about the flipped learning model when they have best grades. We discuss our findings according to six factors that affect the flipped learning experience and, thus, students' perception of flipped learning over time: "student characteristics", "teacher characteristics", "implementation", "task characteristics", "out-of-class activities" and "in-class activities"-factors already unveiled by a recent state-of-the-art review to enhance the effectiveness of flipped classroom. We can conclude that the instructor's teaching experience is a key factor that affects the implementation of flipped learning, influencing students' perception and, consequently, the success of this active methodology.

Perioperative management of children with urea cycle disorders.

BACKGROUND: Urea cycle disorders are congenital metabolism errors that affect ammonia elimination. Clinical signs and prognosis are strongly influenced by peak ammonia levels. Numerous triggers associated with metabolic decompensation have been described with many of them, including fasting or stress, being related to the perioperative period. AIMS: We aimed to assess perioperative complications in pediatric patients with urea cycle disorders requiring general anesthesia in our center. METHODS: We reviewed the clinical history of all the pediatric patients with a confirmed urea cycle disorders diagnosis requiring surgery or a diagnostic procedure with anesthesia between January 2002 and June 2018. RESULTS: We included 33 operations (major surgery, minor surgery, and diagnostic procedures) carried out on 10 patients via different anesthetic techniques. We observed the following complications: intraoperative hyperglycemia in one case, postoperative vomiting in eight cases, and slightly increased postoperative ammonia levels (54, 59, and 69 µmol/L) with normal preoperative levels in three cases without associated metabolic decompensation. There were two cases of perioperative hyperammonemia (72 and 69 µmol/L) secondary to preoperative metabolic decompensation (137 and 92 µmol/L) with the levels progressively dropping and normalizing in the first 24-48 hours, respectively. CONCLUSIONS: Procedures under anesthesia on pediatric patients with urea cycle diseases should be performed by experienced multidisciplinary teams at specialized centers. Perioperative management focused on avoiding catabolism (especially during fasting) and monitoring signs associated with metabolic decompensation to allow for its early treatment should be included in routine anesthetic techniques for children with urea cycle disorders.

Obtención de una versión IgG1 de ratón del rituximab para detectar la molécula CD20 humana / Obtaining a mouse IgG1 version of rituximab to detect the human CD20 molecule

Introducción: El rituximab, anticuerpo quimérico que reconoce la molécula CD20 humana, se ha utilizado en el tratamiento de diversos trastornos linfoproliferativos de células B. Para la selección de los potenciales beneficiarios del tratamiento con rituximab se han desarrollado técnicas que, mediante el uso de anticuerpos monoclonales, detectan la presencia del CD20 en los linfocitos de estos pacientes. Objetivo: Obtener y caracterizar un anticuerpo recombinante IgG1 de ratón específico para la molécula CD20 humana, que contenga las regiones variables del anticuerpo rituximab. Métodos: Para la expresión estable del anticuerpo recombinante se empleó la transducción lentiviral de células de embrión de riñón humano (HEK293). La caracterización inmunoquímica del anticuerpo se realizó por la técnica de Western Blot y su capacidad de reconocimiento de la molécula CD20 humana se evaluó por citometría de flujo e inmunohistoquímica. Resultados: Se obtuvo el anticuerpo 1F5 que reconoce, por citometría de flujo, la molécula CD20 en líneas celulares humanas de origen linfoide, así como en células de sangre periférica de humanos sanos y pacientes con trstornos linfoproliferativos de células B. Sin embargo, la técnica de inmunohistoquímica solo permitió detectar con este anticuerpo la molécula CD20 en tejidos frescos, no así en los embebidos en parafina. Conclusiones: Este trabajo sugiere las potencialidades del uso del anticuerpo 1F5 para las mediciones de la expresión de CD20 por citometría de flujo en pacientes con leucemias B o linfomas B avanzados en fase de leucemización. Esto complementaría los estudios para la selección apropiada de pacientes para el tratamiento con el rituximab(AU)

Introduction: Rituximab, chimeric antibody specific for human CD20 molecule, has been widely used in the treatment of several B-cell linfoproliferative disorders. For the selection of patients with the greatest potential to benefit from the therapy with rituximab, a number of techniques using monoclonal antibodies have been developed to detect the CD20 molecule. Objective: To obtain and to characterize a mouse IgG1 recombinant antibody, specific for human CD20, that contains the variable regions of rituximab. Methods: The lentiviral transduction of human embryonic kidney cells (HEK293) was used for the stable expression of the recombinant antibody. The immunochemical characterization of the antibody was performed by Western Blot and the recognition of CD20 was evaluated by immunohistochemistry and flow cytometry. Results: We generated the antibody 1F5, able to recognize by flow cytometry the CD20 molecule expressed on lymphoid human cell lines, as well as peripheral blood mononuclear cells from healthy donors and patients with B-cell lymphoproliferative disorders. However, 1F5 antibody detected the CD20 molecule on fresh tissues, but not on formalin-fixed paraffin embedded tissues,by immunohistochemistry. Conclusions: This work suggests the potential use of 1F5 antibody for the measurement of CD20 expression by flow cytometry in patients with B-cell leukemias or B-cell lymphomas in phase of leukemization. This could complement the studies to ensure the appropriate selection of patients for the treatment with rituximab(AU)

The role of ecological theory and practice in poverty alleviation and environmental conservation.

The fight against global poverty has gained momentum following the creation of the Millennium Development Goals, which aim to halve extreme poverty by 2015. Traditionally, ecologists have not played leading roles in poverty alleviation. Yet, knowledge of ecosystem functions and processes can be applied to improve the lives of millions of people, suffering from hunger, lacking clean drinking water and reliable, efficient energy sources, dying from preventable diseases, and suffering disproportionately from natural disasters. Here, we describe ways in which ecologists can apply ecological theory and tools to help improve the efficacy of poverty alleviation programs.

Purificación parcial de una tóxina hemolítica y un inhibidor de proteasas a partir de la anemona de mar stoichactis helianthus / Partial purification of a hemolytic toxin and a protease inhibitor from stoichactis helianthus a sea anemona

La obtención de sustancias de origen natural con algún tipo de actividad biológica en células completas o membranas, ha sido motivo de la atención de muchos investigadores, los invertebrados marinos son una fuente de obtención de este tipo de sustancias. En este reporte se describe la purificación parcial de una toxina hemolítica de peso molecular de 11 000 y de un inhibidor de proteasas de peso molecular 4 000, obtenidos a partir de la anémona de mar Stoichactis helianthus. Se determinó la termoestabilidad de ambas sustancias, así como el efecto tóxico la membrana celular de la tóxina hemolítica, lo que hace que sea interesante para la construcción de moléculas híbridas por su unión covalente a anticuerpos y factores de crecimiento; no es así para el inhibidor de proteasa cuya estabilidad constituye una limitante