Recursos educativos digitales como herramientas de apoyo para la enseñanza de patología general en cursos de pregrado del área de la salud / Digital educational resources as support tools for teaching general pathology in undergraduate health courses

Los recursos educativos digitales se han transformado en un importante material de apoyo al proceso de enseñanza- aprendizaje, especialmente durante la pandemia por COVID-19. Estos corresponden a recursos de autoaprendizaje, generalmente en línea y de dominio público cuya disponibilidad inmediata a todo tipo de dispositivos electrónicos permite una rápida interacción del estudiante con materiales didácticos programados. El objetivo de este estudio fue evaluar el grado de satisfacción de cinco recursos educativos digitales, desarrollados como herramientas de apoyo para la enseñanza de la patología general, en estudiantes de carreras de pregrado del área de la salud de la Universidad Austral de Chile. Estudio descriptivo y exploratorio. Se desarrollaron cinco recursos educativos digitales donde se visualizan imágenes microscópicas correspondientes a procesos patológicos ocurridos en diferentes tejidos. Estos recursos fueron alojados en repositorios de la universidad y se encuentran actualmente disponibles en el canal de YouTube. Para conocer el grado de satisfacción, en sus aspectos pedagógicos y técnicos, se realizó una encuesta digital, anónima y voluntaria a estudiantes que cursaron asignaturas de patología, la que contempló cuatro dominios con sus respectivas preguntas: forma; control de usuario; contenido educativo y valoración global. El 94 % de los estudiantes calificaron el recurso de excelente o muy bueno y todos los dominios obtuvieron sobre el 80 % de satisfacción. Los contenidos representan lo que el recurso dice ofrecer, ayuda a resolver dudas y facilita la comprensión de la materia. El tamaño y color del texto es el adecuado y las imágenes presentan una excelente calidad y resolución. Los recursos cumplen con una alta calidad técnica y pedagógica, que asegura un gran potencial de uso para la enseñanza de la patología general, guiar el trabajo autónomo del estudiante y las actividades prácticas con el microscopio.

SUMMARY: Digital educational resources have become an important material to support the teaching-learning process, especially during the COVID-19 pandemic. These correspond to self-learning resources, generally online and the public domain, whose immediate availability to all types of electronic devices allows for rapid learner interaction with programmed didactic materials. The public domain and its immediate availability to all types of electronic devices allows a quick interaction of the student with self-explanatory didactic materials. The objective of this study was to evaluate the degree of satisfaction of five digital educational resources, developed as support tools for the teaching of general pathology, in undergraduate students of the health area of the Universidad Austral de Chile. Descriptive and exploratory study. Five digital educational resources have been developed where microscopic images corresponding to pathological processes occurring in different tissues are visualized these resources were hosted in university repositories and uploaded to the YouTube channel. To determine the degree of satisfaction, in their pedagogical and technical aspects, an anonymous and voluntary digital survey was carried out among students taking pathology courses, which included four domains with their respective questions: form; user control; educational content and overall assessment. The 94 % of the students evaluated the resource as excellent or very good and all domains obtained over 80 % satisfaction. The contents represent what the resource says it offers, helps to resolve doubts and facilitates the understanding of the subject. The size and color of the text is adequate, and the images present excellent quality and resolution. The resources developed offer a high technical and pedagogical quality, which guarantees a great potential for use in the teaching of general pathology, guiding the student's autonomous work and practical activities with the microscope.

Application of Chitosan and Chondroitin Sulphate Aerogels in a Patient With Diabetes With an Open Forefoot Transmetatarsal Amputation.

INTRODUCTION: Diabetic foot ulcers may lead to nontraumatic amputations of the foot, leading to a decrease in patient quality of life. Transmetatarsal amputations (TMAs) represent an effective surgical procedure in cases of severe foot infection, but the tissue reconstruction is complicated and additional procedures should be considered. The present case report evaluates the wound closure of an open TMA in a patient with diabetes treated with a new aerogel composed of chitosan (ChS) and chondroitin sulphate (CS), without needing a skin graft. CASE REPORT: A 72-year-old man with diabetes and a history of successive amputations was admitted to a hospital in Valdivia, Chile, due to a severe infection of toes 2 and 4 of the right foot. After the diagnosis of gangrene and osteomyelitis, the patient underwent a TMA of his right forefoot. The surgeon proposed the incorporation of ChS and CS aerogels to accelerate wound healing to avoid another surgical procedure. The TMA surgical wound area closed 50% after day 28 from starting treatment with aerogels. Complete closure was achieved at day 94 of treatment with aerogels, with good epithelial tissue and favorable cosmetic results and without residual limb deformities. The patient experienced minimal physical and psychological impairment from the procedure. Other surgical procedures were not necessary. CONCLUSIONS: Due to the results of this patient, use of ChS and CS aerogels could represent an alternative treatment for forefoot TMA wound closure and prevent further surgical procedures, such as skin grafting. Future works should consider a larger number of cases.

Ionic Nanocomplexes of Hyaluronic Acid and Polyarginine to Form Solid Materials: A Green Methodology to Obtain Sponges with Biomedical Potential.

We report on the design, development, characterization, and a preliminary cellular evaluation of a novel solid material. This material is composed of low-molecular-weight hyaluronic acid (LMWHA) and polyarginine (PArg), which generate aqueous ionic nanocomplexes (INC) that are then freeze-dried to create the final product. Different ratios of LMWHA/PArg were selected to elaborate INC, the size and zeta potential of which ranged from 100 to 200 nm and +25 to -43 mV, respectively. Turbidimetry and nanoparticle concentration analyses demonstrated the high capacity of the INC to interact with increasing concentrations of LMWHA, improving the yield of production of the nanostructures. Interestingly, once the selected formulations of INC were freeze-dried, only those comprising a larger excess of LMWHA could form reproducible sponge formulations, as seen with the naked eye. This optical behavior was consistent with the scanning transmission electron microscopy (STEM) images, which showed a tendency of the particles to agglomerate when an excess of LMWHA was present. Mechanical characterization evidenced low stiffness in the materials, attributed to the low density and high porosity. A preliminary cellular evaluation in a fibroblast cell line (RMF-EG) evidenced the concentration range where swollen formulations did not affect cell proliferation (93-464 µM) at 24, 48, or 72 h. Considering that the reproducible sponge formulations were elaborated following inexpensive and non-contaminant methods and comprised bioactive components, we postulate them with potential for biomedical purposes. Additionally, this systematic study provides important information to design reproducible porous solid materials using ionic nanocomplexes.

Aerogels made of chitosan and chondroitin sulfate at high degree of neutralization: Biological properties toward wound healing.

In this study, highly neutralized, highly porous, and ultralight polymeric aerogels prepared from aqueous colloidal suspensions of chitosan (CS) and chondroitin sulfate (ChS) nanocomplexes, formulated as quasi-equimolar amounts of both, are described. These aerogels were designed as healing agents under the inspiration of minimizing the amount of matter applied to wounds, reducing the electrostatic potential of the material and avoiding covalent cross-linkers in order to decrease metabolic stress over wounds. Aerogels synthesized under these criteria are biocompatible and provide specific properties for the induction of wound healing. They do not affect neither the metabolic activity of cultured 3T3 fibroblasts nor the biochemical parameters of experimental animals, open wounds close significantly faster and, unlike control wounds, complete reepithelialization and scarring can be attained 14 days after surgery. Because of its hydration abilities, rapid adaptation to the wound bed and the early accelerator effect of wound closure, the CS/ChS aerogels appear to be functional inducers of the healing. Previous information show that CS/ChS aerogels improve wound bed quality, increase granulation tissue and have pain suppressive effect. CS/ChS aerogels are useful as safe, inexpensive and easy to handle materials for topical applications, such as skin chronic wounds. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2464-2471, 2018.

Relevance of charge balance and hyaluronic acid on alginate-chitosan sponge microstructure and its influence on fibroblast growth.

The study of biomaterials by electrical charge scaling to explore the role of net charge on biocompatibility and suitability for tissue regeneration has been limited as has the search for products that could improve this first-rate variable. In the present study, we prepared sponges composed of chitosan/alginate (CS/ALG) with or without hyaluronic acid (HA) by mixing polymer stock solutions of different net electric charge ratios (n(+/) n(-) ), and then lyophilizing them to obtain porous materials. The electric charge ratios n(+/) n(-) studied were 0.3, 0.8, 1.0, and 2.5 for CS/ALG and 0.3, 1.0, 1.9, and 3.7 for CS/ALG/HA sponges. Under these conditions a role for net electric charge balance over sponge microstructure rearrangement, protection to dissolution, cellular proliferation, and cell-cell interactions was apparent, effects that were enhanced by copolymer modification with HA. Mass balance, electric charge, and specific products that influence both such as HA, have a potential in biomaterials for wound healing. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2537-2543, 2016.

Nanoparticles for the Treatment of Wounds.

The treatment of skin wounds represents an important research area due to the important physiological and aesthetic role of this tissue. During the last years, nanoparticles have emerged as important platforms to treat skin wounds. Silver, gold, and copper nanoparticles, as well as titanium and zinc oxide nanoparticles, have shown potential therapeutic effects on wound healing. Due to their specific characteristics, nanoparticles such as nanocapsules, polymersomes, solid lipid nanoparticles, and polymeric nanocomplexes are ideal vehicles to improve the effect of drugs (antibiotics, growth factors, etc.) aimed at wound healing. On the other hand, if active excipients are added during the formulation, such as hyaluronate or chitosan, the nanomedicine could significantly improve its potential. In addition, the inclusion of nanoparticles in different pharmaceutical materials may enhance the beneficial effects of the formulations, and allow achieving a better dose control. This paper aims at reviewing significant findings in the area of nanoparticles and wound treatment. Among the reviewed topics, we underline formulations comprising inorganic, polymeric, surfactant self-assembled, and lipid nanosystems. Among the drugs included in the nanoformulations, the paper refers to antibiotics, natural extracts, proteins, and growth factors, among others. Finally, the paper also addresses nanoparticles embedded in secondary vehicles (fibers, dressings, hydrogels, etc.) that could improve their application and/or upgrade the release profile of the active.

A Simple Mathematical Model for Wound Closure Evaluation.

The incidence of ulcers associated to type 2 diabetes mellitus (T2DM) increases every year. We introduce and explore a new mathematical algorithm to evaluate wound-healing in foot ulcers associated to T2DM. Fifteen patients (nine women and six men), mean age of 70 ± 16 years were included. The evolution of their wounds followed-up for a period of 18-45 days. According to the Wagner grading system the ulcers were grade I (5 patients), grade II (9 patients), and grade III (1 patient). Clinically, the type of the ulcers was neuroischemic (12 patients) and neuropathic (3 patients). A new parameter is introduced, the "continuous linear healing rate" Dc that was more accurate with higher values and requires less quantifications than usual formulas to make a wound-healing projection.

Therapeutic potential of a low-cost device for wound healing: a study of three cases of healing after lower-extremity amputation in patients with diabetes.

Diabetic foot ulcers constitute a tremendous challenge for patients, caregivers, and health care systems. The high incidence and high financial costs associated with their treatment have transformed them in a health and economic worldwide problem. The increase in population life expectancy and lifestyle changes have facilitated the spreading of diabetes, rising diabetic foot ulcer incidence. Only 60%-80% of the patients achieve healing of ulcers, and the incidence of a second ulcer, in the same or different site of the foot that has had a previous ulcer, is approximately 50% in 2-5 years. In addition, ulcers with duration longer than 4 weeks are commonly associated with bad results in healing and an increased risk of amputation. Three patients with type 2 diabetes mellitus have been subjected to treatment with NL.1.2, a low-cost, biocompatible solid device that presented pro-angiogenic properties. The selected patients had undergone amputation, and their wounds, classified as Wagner II, did not show a significant progress in healing after a period of 2-5 months before treatment with NL.1.2. Complete closure of their wounds was achieved in 42-60 days.

Disruptores endocrinos y obesidad: obesógenos / Endocrine disruptors and obesity: obesogens

La incidencia y prevalencia de sobrepeso y obesidad ha experimentado un gran incremento en las últimas tres décadas y afecta a casi todos los países del orbe. Este fenómeno no se explica fácilmente por los cambios del estilo de vida en las distintas poblaciones con hábitos de partida muy distintos. Por lo que además del cambio del estilo de vida, otros factores empiezan a tenerse en cuenta, los llamados disruptores endocrinos y más concretamente los obesógenos. Revisamos la evidencia que existe sobre sustancias químicas que polucionan el ambiente que potencialmente puedan ser obesógenos en humanos: el dietilestilbestrol (DES), la ginesteína, el bisfenol-A, los derivados orgánicos de estaño y los ftalatos. Los tres primeros actúan principalmente sobre los receptores estrogénicos y los derivados orgánicos del estaño y los ftalatos activando los PPARγ. En conclusión, existen evidencias del efecto obesógeno de estas sustancias en estudios en animales de experimentación, tanto in vitro como in vivo, pero muy pocas en humanos. (AU)

ncidence and prevalence of owerweight and obesity have greatly increased over the past three decades in almost all countries around the world. This phenomenon is not easily explained by lifestyle changes in populations with very different initial habits. This has led to consider the influence of other factors, the so-called endocrine disruptors, and more specifically obesogens. This study reviewed the available evidence about polluting chemical substances which may potentially be obesogens in humans: DES, genistein, bisphenol A, organotins (TBT, TPT), and phthalates. The first three groups of substances mainly act upon estrogen receptors, while organotins and phthalates activate PPARγ. It was concluded that evidence exists of the obesogenic effect of these chemical substances in tissues and experimental animals, but few data are available in humans (AU)

[Endocrine disruptors and obesity: obesogens]. / Disruptores endocrinos y obesidad: obesógenos.

Incidence and prevalence of owerweight and obesity have greatly increased over the past three decades in almost all countries around the world. This phenomenon is not easily explained by lifestyle changes in populations with very different initial habits. This has led to consider the influence of other factors, the so-called endocrine disruptors, and more specifically obesogens. This study reviewed the available evidence about polluting chemical substances which may potentially be obesogens in humans: DES, genistein, bisphenol A, organotins (TBT, TPT), and phthalates. The first three groups of substances mainly act upon estrogen receptors, while organotins and phthalates activate PPARγ. It was concluded that evidence exists of the obesogenic effect of these chemical substances in tissues and experimental animals, but few data are available in humans.