Escape Room como Herramienta Didáctica en la Enseñanza de la Histología / Escape Room as a Didactic Tool in Histology Teaching

En el marco de un proceso de aprendizaje activo, se investigó el rendimiento académico a corto y a largo plazo de los estudiantes en dos sesiones prácticas de la asignatura de Histología a las que se incorporó un escape room. También se evaluó su impacto en la motivación y la retención del conocimiento. Los estudiantes fueron clasificados en un grupo control, que siguió una metodología de enseñanza tradicional, y un grupo experimental, que participó en la actividad del escape room. Los resultados revelaron mejoras significativas en las calificaciones posteriores a la intervención en el grupo experimental. El estudio también evaluó la percepción estudiantil de la experiencia del escape room que demostró valoraciones muy satisfactorias.

SUMMARY: In the context of an active learning process, this study investigated the short-term and long-term academic performance of students in two practical sessions of the Histology course, which included an escape room activity. The impact of this approach on motivation and knowledge retention was also assessed. Students were divided into a control group, which followed a traditional teaching methodology, and an experimental group, which participated in the escape room activity. The results revealed significant improvements in post-intervention grades in the experimental group. Additionally, the study assessed students' perceptions of the escape room experience, which showed highly satisfactory evaluations.

Gamificación educativa en el laboratorio de biología celular / Educational gamification in the cell biology laboratory

La incorporación de estrategias de gamificación en la docencia se ha descrito como una herramienta para aumentar la motivación y el compromiso de los alumnos con la materia. Bajo esta premisa, se ha desarrollado una experiencia de innovación educativa mediante la plataforma Kahoot! en la primera y última práctica de laboratorio de la asignatura de Biología Celular del Grado en Biología. Los participantes fueron 135 alumnos repartidos en 12 grupos de laboratorio, que se dividieron entre experimentales y controles. Todos los grupos resolvieron un cuestionario en papel acerca de los conceptos explicados en clase, al finalizar ambas prácticas (post-test), pero sólo aquellos grupos experimentales resolvían un cuestionario antes de la clase (pre-test). Antes de la primera práctica, los alumnos de los grupos experimentales respondieron al pre-test mediante el Kahoot! Sin embargo, para la última práctica algunos grupos lo resolvieron jugando al Kahoot! y otros, con papel y bolígrafo. Los resultados mostraron que aquellos alumnos que fueron seleccionados para jugar a Kahoot!, obtuvieron un mayor número de aciertos en el test realizado tras la sesión práctica (post-test) con respecto a aquellos que no resolvieron ningún pre-test o, que lo hicieron de un modo clásico. Por lo tanto, nuestros resultados sugieren que implementar la jugabilidad en la docencia incrementa considerablemente la motivación del alumnado debido, probablemente, a cambios fisiológicos experimentados por el cerebro durante el juego y a la creación de un clima positivo, que facilitan el proceso de aprendizaje.

SUMMARY: The incorporation of gamification strategies in teaching has been described as a tool to increase the motivation and engagement of students with the subject. Under this premise, an educational innovation experience has been developed using the Kahoot! platform in the first and last laboratory practice of the Cell Biology course of the Biology degree. The participants were 135 students divided into 12 laboratory groups, which were divided into experimental and control groups. All groups solved a questionnaire on paper about the concepts explained in class, at the end of both practices (post-test), but only the experimental groups solved a questionnaire before the class (pre-test). Before the first practice, students in the experimental groups answered the pre-test using Kahoot! However, for the last practice, some groups solved it by playing Kahoot! and others with pen and paper. The results showed that those students who were selected to play Kahoot! obtained a higher number of correct answers in the test performed after the practical session (post-test) than those who did not solve any pre- test or who did it in a classical way. Therefore, our results suggest that implementing gamification in teaching considerably increases student motivation, probably due to physiological changes experienced by the brain during the game and the creation of a positive climate, which facilitates the learning process.

Cone distribution and visual resolution of the yellow-legged gull, Larus michahellis (Naumann, 1840).

The morphological characteristics of the yellow-legged gull's photoreceptors and cone distribution were studied using light and electron microscopy. In wholemount fresh retinas, five different coloured oil droplets located in the cone inner segments could be seen and characterized by colour, diameter and stratification. The photoreceptors were classified by comparing the fresh and fixed vertical sections under a light and electron microscope. Rods were easily distinguished from cones based on the outer segment morphology and the absence of oil droplets in their inner segments. Four types of single cones were associated with red, yellow, colourless and transparent oil droplets. Unequal double cones comprised a long principal member with a green oil droplet and an accessory short member containing a green microdroplet which was highly electron-dense under electron microscopy. The different types of oil droplets were counted from microphotographs of fresh retinal samples in 20 regions. The density, percentage and diameter of the oil droplets were determined. The results showed that central regions had the highest oil droplet density which decreased towards the retinal periphery in all quadrants. Moreover, the oil droplet density was higher in the dorsotemporal quadrant than in other retinal regions. The average density of the red oil droplets was highest in the central areas, whereas colourless oil droplets had the highest density throughout the retina. In contrast, transparent oil droplets had the lowest density across all the regions of the retina. Finally, the retinal resolution was 52.61 cycles/degree. It was calculated using the posterior nodal distance and the oil droplet diameter. The work concludes by discussing the significance of the relative proportion of different cone types across the retina.

A comparative ultrastructural study of the pecten oculi in adult, juvenile, and nestling yellow-legged gulls, Larus michahellis (Naumann, 1840).

This study aimed at examining the histological structure of the pecten oculi in the adult yellow-legged gull, Larus michahellis, and at two moments of postnatal development: during the posthatch (nestling) and juvenile periods. Particular attention was paid to differences in the diameter of vessels, the thickness of the basement membrane, and ultrastructural features of endothelial and pigmented stromal cells. Capillary endothelial cells displayed numerous microvillous-like folds projecting from their internal and external surfaces. Intercellular spaces between capillaries were occupied by pigmented stromal cells. The ultrastructure of pecten oculi underwent noticeable changes during postnatal development. The examination of the capillaries in nestlings, juveniles, and adults revealed that the formation process of vessels and pigmented stromal cells did not complete itself in the posthaching phase. The prominent feature of endothelial cells of capillaries in nestlings was that the microvilli were longer than in juvenile and adult cells, and the capillary lumen was therefore reduced. In this sense, their pigmented stromal cells showed fewer melanosomes, lacked intercellular spaces, and cellular junctions could still be observed. These results provide evidence that the pecten oculi during the posthatching phase maintains immature morphological features consistent with a role of pigmented stromal cells in the blood-retina barrier.

Molecular neurochemistry of the lanthanides.

Lanthanides, once termed rare-earth elements, are not as sparce in the environment as their traditional name suggests. Mean litospheric concentrations are in fact comparable to the physiologically fundamental elements such as iodine, cobalt, and selenium. Recent advances in medical technology have resulted in accumulation of lanthanides presenting potential exposure to both our central and peripheral nervous systems. Extensive and detailed studies on these peculiar active metals in the context of their influence on neural functions are therefore urgently required. Almost all neurochemical effects of trivalent lanthanide ions appear to result from the similarity of their radii to the key signaling ion calcium. Lanthanides, especially La3+ and Gd3+ block different types of calcium, potassium, and sodium channels in human and animal neurons, regulate neurotransmitter turnover and release, as well as synaptic activity. Lanthanides also act as modulators of several ionotropic receptors, e.g., GABA, NMDA, and kainate and can also affect numerous signaling mechanisms including NF-κB and apoptotic-related endoplasmic reticulum IRE1-XBP1, PERK, and ATF6 pathways. Several lanthanide ions may cause oxidative neuronal injuries and functional impairment by promoting reactive oxygen species production. However, cerium and yttrium oxides have some unique and promising neuroprotective properties, being able to decrease free radical cell injury and even alleviate motor impairment and cognitive function in animal models of multiple sclerosis and mild traumatic brain damage, respectively. In conclusion, lanthanides affect various neurophysiological processes, altering a large spectrum of brain functions. Thus, a deeper understanding of their potential mechanistic roles during disease and as therapeutic agents requires urgent elucidation.

Students' Views on Difficulties in Learning Histology.

The aim of this study was to provide a better understanding of the main difficulties hindering undergraduate biology students in learning histology. The study utilized a self-administered questionnaire which included three closed-ended and two open-ended questions: (1) if students had difficulty in learning about each tissue type; (2) what might be the problem in learning about the tissue at hand; (3) which topics were the most difficult; (4) what were the possible reasons that made image identification of tissue types difficult; and (5) how to improve the course curriculum from a student perspective. The survey was administered to 139 undergraduate biology students enrolled in a histology course, of which 101 surveys were completed and analyzed both qualitatively and quantitatively. The topics that students experienced the most difficulties with were: nervous tissue, plant tissues, bone tissues, and glandular epithelial tissue. The main reasons students experienced difficulties with these tissue types, according to the students themselves, were the nature of the topic, grasping the terminology used, and insufficient teaching time. Students suggested the adoption of strategies such as: teaching based on practical tasks; reducing the content of the histology curriculum; adding anatomy subjects; and making histology education more interesting.

A different ultrastructural face of ribbon synapses in the rat retina.

Ribbon synapses located exclusively within retinal, cochlear and vestibular connections belong to the most interesting cellular structures but their molecular nature and functions had remained unclear. The study has provided a descriptive morphological analysis of rat eye ribbon synapses using high-resolution transmission electron microscopy (TEM). An original collection of untypical, rarely present in the literature sagittal or tangential sections through the single RIBEYE domain of the particular ribbon have been delivered.

Ultrastructural characteristics of human oocytes vitrified before and after in vitro maturation.

The development of an effective program that combines in vitro maturation (IVM) and cryopreservation for immature oocytes would represent a novel advance for in vitro fertilization (IVF), especially as a means to preserve the fertility of women in unique situations. The aim of this study was to analyze the ultrastructural characteristics of human oocytes, obtained after controlled ovarian stimulation, to determine whether IVM is best performed before or after vitrification. To this end, we analyzed the following features in a total of 22 MII oocytes: size, zona pellucida and perivitelline space, mitochondria number, M-SER (mitochondria-smooth endoplasmic reticulum) aggregates and M-V (mitochondria-vesicle) complexes, the number of cortical granules and microvilli, and the presence of vacuolization using transmission electron microscopy (TEM). Each oocyte presented a rounded shape, with an intact oolemma, and was surrounded by a continuous zona pellucida and perivitelline space. Statistical analysis comparing oocytes vitrified before or after IVM indicated that there were no significant differences between examined characteristics.

Does Müller Cell Differentiation Occur Prior to the Emergence of Synapses in Embryonic Turtle Retina?

Müller cells are the main glial cells in the retina, and are related to plexiform layer activity. Recent studies have demonstrated that Müller cells are involved in the synaptic conservation, plasticity, development and metabolism of glutamate. During turtle retinal development, layers, cells and synapses appear at different times. The aim of this research is to study the emergence of Müller cells during embryonic development and their relationship with the synaptogenesis. The authors used retinas from Trachemys scripta elegans embryos at stages S14, 18, 20, 23, and 26. Some retinas were processed with immunocytochemistry in order to detect the presence of glutamine synthetase in Müller cells, which was used as a marker of these cells. Other retinas from the same stages were processed for ultrastructural studies. Samples were observed in confocal and transmission electron microscopes, respectively. The present results show that glutamine synthetase expression in Müller cells occurs at S18, before the emergence of the retinal layers and the early synapses.