RESUMO
Muscular dystrophies (MDs) are a heterogeneous group of diseases of genetic origin characterized by progressive skeletal muscle degeneration and weakness. There are several types of MDs, varying in terms of age of onset, severity, and pattern of the affected muscles. However, all of them worsen over time, and many patients will eventually lose their ability to walk. In addition to skeletal muscle effects, patients with MDs may present cardiac and respiratory disorders, generating complications that could lead to death. Interdisciplinary management is required to improve the surveillance and quality of life of patients with an MD. At present, pharmacological therapy is only available for Duchene muscular dystrophy (DMD)-the most common type of MD-and is mainly based on the use of corticosteroids. Other MDs caused by alterations in dystrophin-associated proteins (DAPs) are less frequent but represent an important group within these diseases. Pharmacological alternatives with clinical potential in patients with MDs and other proteins associated with dystrophin have been scarcely explored. This review focuses on drugs and molecules that have shown beneficial effects, mainly in experimental models involving alterations in DAPs. The mechanisms associated with the effects leading to promising results regarding the recovery or maintenance of muscle strength and reduction in fibrosis in the less-common MDs (i.e., with respect to DMD) are explored, and other therapeutic targets that could contribute to maintaining the homeostasis of muscle fibers, involving different pathways, such as calcium regulation, hypertrophy, and maintenance of satellite cell function, are also examined. It is possible that some of the drugs explored here could be used to affordably improve the muscular function of patients until a definitive treatment for MDs is developed.
Assuntos
Distrofias Musculares , Humanos , Distrofias Musculares/tratamento farmacológico , Distrofias Musculares/fisiopatologia , Distrofina , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Distrofia Muscular de Duchenne/tratamento farmacológico , Distrofia Muscular de Duchenne/fisiopatologia , Complexo de Proteínas Associadas DistrofinaRESUMO
OBJECTIVE: Evaluate the role of cognitive reserve (CR) on cognitive and physical sequelae in traumatic brain injury (TBI). METHODS: A comprehensive search strategy was conducted in four databases in English and Spanish in the last 12 years (2011-2023). Inclusion criteria: original cross-sectional and longitudinal studies whose main or secondary objective was to evaluate the effect of CR in adult patients with TBI. PRISMA guidelines were used to report the search and selection method and STROBE checklist was used to evaluate the quality of studies. RESULTS: Eighteen observational studies were included in this review. Multiple sources of variability were observed: number of patients, time of evolution, severity of the TBI, type of CR proxy, cognitive assessment instrument, etc. However, the most commonly used indicators of CR were premorbid IQ and educational attainment. A positive and consistent association between CR and performance on cognitive tests after injury was found. CONCLUSIONS: CR has a consistent positive effect on cognition and on some other aspects of recovery in traumatic brain injury. In future studies, it will be necessary to promote the use of CR indices based on various indicators and explore the effects of CR on other aspects related to the recovery of brain trauma.
Assuntos
Lesões Encefálicas Traumáticas , Reserva Cognitiva , Estudos Observacionais como Assunto , Humanos , Lesões Encefálicas Traumáticas/psicologia , Lesões Encefálicas Traumáticas/complicações , Reserva Cognitiva/fisiologiaRESUMO
Resumen La intoxicación por metanol puede ocurrir de forma inadvertida por la ingesta de bebidas alcohólicas adulteradas. Se trata una entidad poco frecuente, sin embargo, se ha reportado un aumento en la incidencia durante la pandemia de COVID-19. La intoxicación con metanol representa una urgencia médica, ya que puede provocar daño severo en el sistema nervioso central y periférico, además de acidosis metabólica, daño renal agudo e incluso la muerte. En este artículo se presenta el caso de un paciente que cursó con intoxicación por metanol de manera inadvertida al consumir bebidas alcohólicas presumiblemente adulteradas. En el encéfalo se demostró necrosis hemorrágica de ambos núcleos putamen, además de cursar con neuritis óptica bilateral y polineuropatía periférica. Fue manejado con pulsos de esteroides intravenosos, con lo cual, mejoró significativamente su función visual, sensitiva y motora. En el presente caso no existieron complicaciones fatales y presentó una buena respuesta al tratamiento, sin embargo, el caso pone de relieve la necesidad de una mejor regulación en la producción y comercialización de bebidas alcohólicas en nuestro país, y, por otro lado, permite hacer a un llamado a los consumidores a tomar más precauciones en el consumo de bebidas alcohólicas de dudosa calidad o procedencia.
Abstract Methanol poisoning can occur unnoticed, by the ingestion of adulterated alcoholic beverages. In general, it is a rare entity, however, an increase in incidence has been reported during the SARS-CoV-2 pandemic. Methanol poisoning represents a medical emergency as it can cause severe damage to the central and peripheral nervous systems, as well as metabolic acidosis, acute kidney injury, and even death. This article presents the case of a patient who inadvertently developed methanol intoxication after consuming presumably adulterated alcoholic beverages. In the brain, hemorrhagic necrosis of both putamen nuclei was demonstrated, in addition to presenting with bilateral optic neuritis and peripheral polyneuropathy. He was managed with intravenous steroid pulses, which significantly improved his visual, sensory, and motor function. In the present case there were no fatal complications and presented a good response to treatment, however, the case highlights the need for better regulation in the production and marketing of alcoholic beverages in our country, and on the other hand, to invite consumers to take more precautions in the consumption of alcoholic beverages of dubious quality or origin.
RESUMO
Resumen: El organismo de la mujer experimenta una serie de cambios fisiológicos, a todos niveles, que tienen la finalidad de adaptarse y dar respuesta a la gran demanda que representan las 40 semanas de gestación que durará la formación un nuevo ser humano en su interior. Dichos cambios ocurren de manera gradual, pero continua, a lo largo de todo el embarazo y van desde cambios cardiovasculares, digestivos, pulmonares, hematológicos y endocrinos, los cuales al final también terminan por revertirse de manera paulatina durante el puerperio. Los cambios fisiológicos se relacionan con el desarrollo de distintos síntomas, signos y alteraciones en la mujer embarazada, así como cambios en los parámetros de los estudios paraclínicos, lo cual hace que resulte especialmente relevante que el médico general o de primer contacto esté familiarizado con estos cambios y el momento en el que ocurren en el embarazo, para que pueda realizar una oportuna identificación de las alteraciones que pueden representar estados patológicos que resulten una amenaza para el bienestar materno y fetal. Por todo lo anterior, el objetivo de la presente revisión temática fue recopilar y describir los principales cambios fisiológicos que ocurren en la mujer durante el embarazo normal, así como los cambios que se presentan en los estudios paraclínicos más comunes.
Abstract: The woman's body undergoes a series of physiological changes at all levels that hace the purpose of adapting and responding to the the 40 weeks of gestation. These changes occur gradually, but in a continuously, throughout the pregnancy and range from cardiovascular, digestive, pulmonary, hematological and endocrine changes, which at the end also end up gradually reversing during the puerperium. The physiological changes are related to the development of different symptoms, signs and alterations in the pregnant woman, as well as changes in the parameters of the paraclinical studies, which makes it especially relevant for the general practitioner or first contact doctor to recognize these changes and the moment in which they occur in pregnancy so that they can make a timely identification of the alterations that can represent pathological states that are a threat to maternal and fetal well-being. For all of the above, the objective of this thematic review was to collect and describe the main physiological changes that occur in women during a normal pregnancy, as well as the changes that occur in the most common paraclinical studies.
RESUMO
Resumen Desde hace décadas, el ritmo de la vida moderna ha generado múltiples cambios en nuestra conducta y hábitos. Especialmente, los hábitos alimenticios y de ejercicio se han modificado de manera importante, pero uno de los cambios más evidentes ha ocurrido en el sueño. En la actualidad, el tiempo dedicado a este ha disminuido drásticamente, pero no solo se trata de la cantidad, sino también de la calidad del sueño que se ha visto afectada de forma relevante en todos los grupos de edad, en especial en la población joven. Desde hace algunos años se sabe que el sueño juega un papel muy importante para el óptimo funcionamiento físico y mental del ser humano, pero solo recientemente hemos comenzado a conocer y entender las consecuencias que una mala calidad del sueño puede tener sobre la salud a mediano y largo plazo. En esta revisión se incluyen los trastornos del sueño más comunes o representativos, los estudios que se utilizan para su diagnóstico y, finalmente, se da un panorama general sobre las consecuencias de estos trastornos en la salud a largo plazo.
Abstract For decades, the rhythm of modern life has generated multiple changes in our behavior and habits. Especially, the way we eat and our exercise habits have changed significantly but one of the most evident effects is regarding sleep behavior. Nowadays, sleep has decreased dramatically, but not only in quantity. The quality of sleep has been affected in a significant way on all age groups, especially in the young population. For several years, we've known that sleep plays an essential role for an optimal physical and mental performance in the human being. Only recently we've begun to discover and understand the consequences that sleep disturbances can have on health in the long term. In the present article we include a general review of the most common or representative sleep disorders, the studies used for their diagnosis and finally we made an overview of the consequences of these disorders on health.
RESUMO
El sueño es un proceso fisiológico fascinante, sólo recientemente algunos de los misterios acerca de su origen, fisiología y funciones biológicas han sido esclarecidos, sin embargo, aún falta mucho por estudiar. La investigación sobre la biología del sueño y sobre los efectos clínicos de sus trastornos cada vez deja más en claro que el sueño es un proceso de vital importancia para la salud integral del ser humano. Sin embargo, según algunos estudios, la tendencia en la población mundial es hacía la reducción del tiempo total de sueño, lo cual se ha reflejado en el incremento en la incidencia de trastornos del sueño. En este sentido, la población joven es especialmente proclive a desarrollar trastornos del sueño principalmente debido a factores externos (sociales y ambientales) y a distintos hábitos que pueden afectar su calidad (consumo de alcohol, tabaco, cafeína, etc.). Este artículo pretende realizar una revisión actualizada acerca de la neurobiología del sueño y de aspectos del sueño que resultan de interés práctico para el estudiante universitario, como el papel del sueño en el proceso de aprendizaje y memoria, así como los efectos que ejercen distintas sustancias de uso común en este grupo de población sobre el proceso de sueño, y finalmente con énfasis en la importancia de una adecuada higiene del sueño para la salud integral del individuo.
Sleep is a fascinating physiological process, only recently some of the mysteries about its origin, physiology and biological functions have been clarified; however, much remains to be studied. Research on sleep biology and the clinical consequences of sleep disorders has made clear that sleep is a vital process for the full health of human beings. Nevertheless, according to some studies, worldwide population tends to reduce total sleep time, which is reflected in the increasing incidence of sleep disorders. In this sense, young people are particularly prone to the development of sleep disorders, mainly due to external factors (social and environmental), and other habits that can influence the quality of sleep (alcohol, tobacco, caffeine, etc.). This article aims at providing an updated review about sleep neurobiology and related aspects of practical interest for university students, such as: the role of sleep in learning and memory processes, as well as the effects produced by several substances, commonly used in this population, on the sleep process; finally emphasizing the importance of appropriate sleep hygiene practices for human health.
RESUMO
According to recent evidence, memory can be conceptualized as a series of subsystems working together to reach the same final goal. In the present time, most authors coincide in proposing a main division or long-term memory systems in mammals. This division separates memory in two categories: declarative and not declarative, often conceptualized also as explicit and implicit memories, respectively, although the latter terms are more appropriate to describe the role of consciousness during the development of codification and recovery tasks in regard to the information of each system. Declarative memory, as indicated by its name, includes a variety of memories implicating information that can be verbalized and effectively transmitted from person to person. This type of memory is conceptualized as conformed by two distinct memory sub-categories sometimes collaborating and coinciding in the use of memory. The first of these sub-categories is semantic memory, the one including the information about concepts and precise facts, and it is frequently defined as «general knowledge¼. It also makes reference to conceptual information lacking from the temporal-spatial frame (this issue is detailed in the first part of this paper). The second sub-category is episodic memory, which refers to the memory for personal experienced events, or the memory used for «what?, where?, and when?¼, in regard to the occurrence of a given personal event. Altogether, autonoesis (the conscious concept of a personally experienced event), subjective temporal consciousness (or subjective temporal frame about when a given event occurred), and self-consciousness are considered indispensable for the definition of episodic memory. In spite of these characteristics, there is yet controversy on whether this type of memory could be observed in animals. In this regard, some researchers have demonstrated that the processes needed to define episodic memory are effectively employed by non-human primates and rodents. In regard to the functional anatomy of episodic memory, an active role of the temporal lobe in the codification of some components of this memory is known from long time ago. Experimental studies employing hippocampal electro-physiological recordings have demonstrated that this region participates in two main components of episodic memory: i) the strong links of the subject with the environment or the spatial context, and ii) the temporal organization of the stored information. Some studies have clearly demonstrated the important participation of specific hippocampal cell areas (CA1 and CA3) for the resolution of behavioral tasks requiring episodic memory. However, clinical studies employing functional imaging have shown a considerable diversity of cortical areas as involved in the several processes of codification or recovery of episodic information, going from prefrontal medial and left ventrolateral regions to medial and lateral temporal regions, retrosplenial cortex, posterior cingulus posterior, and even the cerebellum. Non-declarative memory systems Non-declarative memory contains different categories: procedural memory, priming, associative learning (classic and operant conditioning) and non-associative learning (habituation and sensitization): a) Procedural memory refers to the storage and recovery of information on motor skills, or «know how to do¼ distinct tasks. Although this type of memory is considered as part of those memory systems often leading to unconscious learning, the relationship between procedural memory and consciousness is more complex. This is due in part to the fact that there is no evidence of a real association between the voluntary (conscious) desire of movement and the activation of motor brain areas. In addition, it has been demonstrated that movements consciously activated to start a given task may difficult the performance of the same task. Moreover, learning of motor skills exhibits a particular characteristic known as consolidation or off-line stabilization. This term refers to those motor skills exhibiting an improvement in performance during the interval of two practice sessions, meaning that the performance is improved if behavior is re-analyzed after an interval of rest typically occurring along the day or during sleep periods. This supports the theory that during sleep periods there is a recapitulation of events taking place during the day, thus favoring the strengthening of neuroplastic mechanisms involved in motor learning. b) Priming is a type of implicit memory not requiring any conscious recollection of previous experiences, and it shares some features with procedural and semantic memories. Similar to procedural memory, priming implies an increase of skills, but in this case, perceptual skills. It is also similar to semantic memory in terms of the involvement of cognitive representations of outdoor environment, and its representation is more cognitive than behavioral. The general characteristics of priming are: i) it is related with the perceptual identification of objects in general terms, including words or concepts; ii) its neuronal substrate is not depending on those brain regions needed for episodic or semantic memories; iii) it is developed early in life and its capacity remains stable all the time; iv) its activity is not related with consciousness and its function is not sufficient to recall a previous experience; v) it is relatively immune to the effects of drugs affecting the other memory systems; vi) its information is distributed in multiple representations of specific words and objects; and vii) the access to this representations is highly specific to each category of objects. Finally, among short-term memory systems, the concept of working memory proposed by Baddeley and Hitch is still accepted in our days, and is characterized by the transitory storage and administration of all kind of information useful for the achievement of a specific task. This system is based on three main components: i) a control system with limited attention capacity, also known as Executive Central Component; ii) the Phonologic Circuit, based on sound and language; and iii) the Visual-Spatial Scheme. The phonologic circuit is responsible for the transitory storage of language information based on sound and it is proponed to play an active role for learning of language. The Visual-Spatial Scheme is important for the visual-spatial representation of objects and their features, which in turn is relevant for the integration of concepts. The Executive Central Component is in charge of controlling the attention and the access to the other two subsidiary components. The knowledge on how the memory systems are functioning is and will remain in constant expansion, given the obvious contribution of recent studies on molecular biology and functional neuroimaging.
La memoria episódica (ME) forma parte de los sistemas de memoria declarativa y es considerada como aquella de los sucesos experimentados de forma personal, o sea la memoria del «¿qué?¼, «¿dónde?¼ y «¿cuándo?¼ ocurrió cierto suceso de la experiencia personal. La triada de autonoesis (es decir, la conciencia de que un suceso le ocurrió personalmente), conciencia temporal subjetiva (o el marco temporal subjetivo de cuando ocurrió un suceso y en qué orden) y la conciencia de sí mismo, son consideradas como requisito indispensable para la definición de la memoria episódica. Hasta hace algunos años la memoria episódica era típicamente considerada como una habilidad exclusiva del ser humano, debido a los procesos cognitivos con los que se asocia, sin embargo, recientemente se ha comprobado que otras especies animales tienen y utilizan eficazmente un sistema análogo al de la ME para resolver diversas tareas de memoria en el laboratorio. Estos modelos experimentales de ME han impulsado la generación de conocimientos acerca de este sistema. La participación del lóbulo temporal, y en especial del hipocampo, en la ME es conocida desde hace tiempo, sin embargo se han identificado diversas áreas cerebrales implicadas en la recuperación y codificación de la información episódica. Una de las más estudiadas actualmente es la corteza parietal posterior, pero existen otras cuyo rol preciso en este tipo de memoria aún no se ha esclarecido. Por otro lado, la otra gran categoría central de la memoria: la no declarativa, contiene diversas subcategorías heterogéneas en su contenido y función, como son: la memoria procedimental, el priming, el aprendizaje asociativo (condicionamiento clásico y operante) y el aprendizaje no asociativo (habituación, deshabituación y sensibilización) mediado por vías reflejas. La memoria procedimental se refiere al almacenamiento y recuperación de información sobre habilidades motoras, es decir, el aprendizaje de «saber cómo hacer¼ distintas tareas. La memoria procedimental tiene relaciones complejas con la «conciencia¼, se ha demostrado que presenta un proceso de consolidación off-line, es decir que la información se consolida mejor cuando existe un periodo de reposo entre las sesiones de entrenamiento motor, sobre todo si durante este descanso ocurre el sueño. Existe una serie de estructuras tanto corticales como subcorticales que participan en diversas funciones de la memoria procedimental y cuya lesión selectiva produce distintos trastornos de las funciones motoras, como la parálisis, la apraxia, el temblor, los movimientos coreicos, las distonías, las dismetrías o la ataxia. El priming es un tipo de memoria implícita que no requiere de ninguna recolección consciente de experiencias previas, y que comparte algunas características con la memoria procedimental pero también con la semántica. Se trata de una variedad de memoria en la cual se propone que participan áreas neocorticales de asociación visual. Finalmente, dentro de los sistemas de memoria de corto plazo se encuentra el concepto de memoria de trabajo, propuesto por Baddeley y Hitch, que sigue teniendo aceptación en la actualidad y que es considerado como un sistema encargado de almacenar y administrar transitoriamente toda la información (de distintas modalidades) que se encuentra actualmente en uso para la realización de una tarea específica. Esta memoria de trabajo se conceptualiza como conformada por un componente ejecutivo central y dos sistemas subsidiarios: el circuito fonológico (encargado entre otras cosas del reforzamiento verbal implicado en el aprendizaje del lenguaje) y el esquema visuo-espacial que estaría encargado del almacenamiento transitorio de la información espacial del ambiente externo. El conocimiento científico de la memoria continúa en expansión cotidiana, pero aún estamos lejos de conocer todos los detalles acerca de su funcionamiento desde el nivel molecular hasta el anatómico macroscópico. Sin duda los estudios moleculares y de imagen funcional ofrecerán en el futuro una panorámica más amplia al respecto.