Serious neurological adverse events following immunization against SARS-CoV-2: a narrative review of the literature.

Amid the coronavirus disease 2019 (COVID-19) pandemic, massive immunization campaigns became the most promising public health measure. During clinical trials, certain neurological adverse effects following immunization (AEFIs) were observed; however, acceptable safety profiles lead to emergency authorization for the distribution and use of the vaccines. To contribute to pharmacovigilance and lessen the potential negative impact that vaccine hesitancy would have on immunization programs, we conducted a review of the scientific literature concerning the epidemiological data, clinical presentation, and potential mechanisms of these neurological AEFIs. There is some epidemiological evidence linking COVID-19 vaccines to cerebral venous sinus thrombosis, arterial ischemic stroke, convulsive disorder, Guillain-Barré syndrome, facial nerve palsy, and other neurological conditions. Cerebral venous sinus thrombosis has been associated with a thrombotic thrombocytopenia induced by the vaccine, similar to that induced by heparin, which suggests similar pathogenic mechanisms (likely involving antibodies against platelet factor 4, a chemokine released from activated platelets). Arterial ischemic stroke is another thrombotic condition observed among some COVID-19 vaccine recipients. Vaccine-induced convulsive disorder might be the result of structural abnormalities potentially caused by the vaccine or autoimmune mechanisms. Guillain-Barré syndrome and facial nerve palsy may also be linked to the immunization event, possibly due to immune mechanisms such as uncontrolled cytokine release, autoantibody production, or bystander effect. However, these events are mostly uncommon and the evidence for the association with the vaccine is not conclusive. Furthermore, the potential pathophysiological mechanisms remain largely unknown. Nevertheless, neurological AEFIs can be serious, life-threatening or even fatal. In sum, COVID-19 vaccines are generally safe and the risk of neurological AEFIs does not outweigh the benefits of immunization. However, early diagnosis and treatment of neurological AEFIs are of utmost importance, and both health professionals and the public should be aware of these conditions.

A review of undesired effects involving the nervous system following the administration of COVID-19 vaccines Among the range of complications that can occur after a vaccine, some of them can affect the nervous system and its vasculature. This narrative review aims to evaluate some serious neurological conditions following COVID-19 vaccination. We searched biomedical journal databases where physicians around the globe reported different complications after the administration of different COVID-19 vaccines. Besides reports of cases in individual patients or small groups, we reviewed studies that included bigger groups of patients (e.g. vaccinated versus non-vaccinated) and compared the occurrence of these events between them. We found that after the administration of a certain type of vaccine (e.g. ChAdOx1-S/Oxford, AstraZeneca vaccine), serious neurological complications were rare, with abnormal clot formation involving cerebral blood vessels being one of the most important among them. Nonetheless, other conditions have been observed after the administration of the vaccines; however, it is not certain yet if the vaccines are the actual cause of these complications. There are some hypotheses that could explain why these adverse reactions take place after a vaccine. For instance, an abnormal immune response to the vaccine leads to the production of antibodies (i.e. proteins made by the immune system in response to the presence of a foreign substance). These antibodies trigger a response that could eventually result in clot formation. Besides, the immune response can also produce other adverse effects, including convulsive disorder, Guillain­Barré syndrome, and facial nerve palsy. Scientific evidence suggests that vaccines are safe overall. While mild complications, such as pain at the site of injection or bruising might occur, more serious events remain rare. Furthermore, the complications derived from COVID-19 are far more likely in non-vaccinated individuals than the complications associated with the vaccine. Thus, vaccination continues to be the safest and most effective strategy to control the ongoing pandemic. However, both health professionals and the public should be aware of the possibility of serious neurological adverse reactions occurring after vaccination to allow early diagnosis and treatment.

Connexins and Pannexins: Important Players in Neurodevelopment, Neurological Diseases, and Potential Therapeutics.

Cell-to-cell communication is essential for proper embryonic development and its dysfunction may lead to disease. Recent research has drawn attention to a new group of molecules called connexins (Cxs) and pannexins (Panxs). Cxs have been described for more than forty years as pivotal regulators of embryogenesis; however, the exact mechanism by which they provide this regulation has not been clearly elucidated. Consequently, Cxs and Panxs have been linked to congenital neurodegenerative diseases such as Charcot-Marie-Tooth disease and, more recently, chronic hemichannel opening has been associated with adult neurodegenerative diseases (e.g., Alzheimer's disease). Cell-to-cell communication via gap junctions formed by hexameric assemblies of Cxs, known as connexons, is believed to be a crucial component in developmental regulation. As for Panxs, despite being topologically similar to Cxs, they predominantly seem to form channels connecting the cytoplasm to the extracellular space and, despite recent research into Panx1 (Pannexin 1) expression in different regions of the brain during the embryonic phase, it has been studied to a lesser degree. When it comes to the nervous system, Cxs and Panxs play an important role in early stages of neuronal development with a wide span of action ranging from cellular migration during early stages to neuronal differentiation and system circuitry formation. In this review, we describe the most recent available evidence regarding the molecular and structural aspects of Cx and Panx channels, their role in neurodevelopment, congenital and adult neurological diseases, and finally propose how pharmacological modulation of these channels could modify the pathogenesis of some diseases.

Procesos de evaluación médica en el área clínica. Análisis cualitativo a través de la experiencia de docentes y estudiantes / Medical Evaluation Processes in Clinical settings. Qualitative Analysis through the Experience of Teachers and Studens

Los procesos de evaluación en la práctica clínica médica han sido poco investigados, perfilándose su estudio a la manera técnica de realizarlos. Este estudio buscó realizar una aproximación a los procesos de evaluación clínica en medicina mediante la valoración de las percepciones de docentes y estudiantes acerca de los métodos de evaluación a la luz de los procesos de enseñanza y aprendizaje llevados a cabo en una rotación clínica del programa de Medicina de la Universidad El Bosque en Bogotá. Con este fin se realizaron entrevistas a docentes y estudiantes, indagando sobre la manera como se dan los procesos de evaluación, enseñanza y aprendizaje; posteriormente, se analizó la percepción de ambos agentes sobre la forma como se relacionan dichos procesos. Estas entrevistas fueron categorizadas de manera deductiva e inductiva y contrastadas con las diferentes teorías existentes en enseñanza, aprendizaje y evaluación médicas. Se evidenció que en la actualidad, la evaluación y en general el proceso educativo son afectados por factores asociados a cómo se desarrolla el ejercicio profesional y por la forma en que se desarrolló el proceso educativo de los actuales docentes. Se concluyó que hay incoherencia frente al enfoque de la evaluación primordialmente conductista, en relación con las estrategias de enseñanza y aprendizaje utilizadas enmarcadas en el constructivismo, lo cual se manifiesta en inconformidad de docentes y estudiantes.

Evaluation processes in clinical practice have not been well, being their study focused on the technical issues concerning these processes. This study tried an approach to the evaluation processes through the analysis of perceptions from teachers and students about the methodology of evaluation considering the teachinglearning processes performed in a clinical practice of the Medicine Program -Universidad El Bosque from Bogota . With this purpose we conducted interviews with teachers and students searching the manner in which the evaluative, learning and teaching processes are done; then we analyzed the perception from both agents concerning the way these processes are related. The interviews were categorized bath deductively and inductively, and then contrasted with some current theories of learning, teaching and evaluation in medicine. The study showed that nowadays the evaluation and, in general, the educative processes are affected by several factors which are associated to the manner the professional practice is developed, and the educative process of the current teachers. We concluded there is no congrency between the approach of the evaluation, mainly conductivist, and the learning and teaching strategies mainly constructivist. This fact cause dissent in teachers and students.