Trastornos circadianos del sueño / Circadian Sleep Disorders

Resumen El sistema circadiano está sincronizado al ciclo luz-oscuridad que es generado por la rotación de la tierra, asegurando que la vigilia sea durante el día y que el sueño ocurra durante la noche. Sin embargo, el ritmo de sueño-vigilia puede estar desincronizado del ciclo luz-oscuridad o desincronizado de manera endógena, dando como resultado: insomnio, fatiga y bajo rendimiento en las actividades cotidianas. Mientras que los trastornos del sueño están clasificados por la Asociación Americana de Trastornos del Sueño como: disomnias intrínsecas, disomnias extrínsecas, parasomnias o trastornos del sueño médicos/psiquiátricos. Los trastornos circadianos del sueño se han categorizado por separado, en parte para reconocer que en la mayoría de los casos la etiología de los trastornos circadianos es una mezcla de factores internos y ambientales, o por un desajuste temporal entre ambos. Los síntomas generalmente son insomnio o hipersomnia, síntomas comunes en pacientes con trastornos circadianos del sueño, aunque hay otras causas a las que pueden atribuirse y que deben excluirse antes de realizar el diagnóstico de un trastorno circadiano del sueño. En el paciente sin otra patología del sueño, un registro diario de actividades, comidas, ejercicio, siestas y la hora de acostarse es una herramienta esencial para evaluar los trastornos circadianos del sueño. Estos registros deben mantenerse durante 2 semanas o más, ya que una perturbación debida a cambios de trabajo o viajes a través de zonas horarias puede tener efectos sobre el sueño y el estado de alerta durante el día, semanas después del evento.

Abstract The circadian system is synchronized to the light-dark cycle generated by the rotation of the earth, ensuring that wakefulness is during the day and sleep occurs at night. However, the sleep-wake rhythm may be out of sync with the light-dark cycle or endogenously out of sync, resulting in insomnia, fatigue, and poor performance in activities of daily living. Sleep disorders are classified by the American Sleep Disorders Association, as intrinsic dyssomnias, extrinsic dyssomnias, parasomnias, or medical/psychiatric sleep disorders. Circadian sleep disorders have been categorized separately to recognize that in most cases the etiology of circadian disturbances is a mix of internal and environmental factors or a temporary mismatch between the two. Symptoms are usually insomnia or hypersomnia, common symptoms in patients with circadian sleep disorders although other causes can be attributed and must be excluded before a diagnosis of a circadian sleep disorder is made. In the patient without other sleep pathology, a daily record of activities, meals, exercise, naps, and bedtime is an essential tool in assessing circadian sleep disorders. These records should be kept for 2 weeks or more, as a disturbance due to job changes or travel across time zones can have effects on sleep and daytime alertness weeks after the event.

Effect of a light-darkness cycle on the body weight gain of preterm infants admitted to the neonatal intensive care unit.

The Continuous bright light conditions to which premature infants are subjected while hospitalized in Neonatal Intensive Care Units (NICU) can have deleterious effects in terms of growth and development. This study evaluates the benefits of a light/darkness cycle (LDC) in weight and early hospital discharge from the NICU. Subjects were recruited from three participating institutions in Mexico. Eligible patients (n = 294) were premature infants who were hospitalized in the low-risk and high-risk neonatal units classified as stable. The subjects randomized to the experimental group (n = 150) were allocated to LDC conditions are as follows: light from 07:00 to 19:00 and darkness (25 lx) from 19:00 to 07:00. The control group (n = 144) was kept under normal room light conditions (CBL) 24 h a day. Main outcome was weight gain and the effect of reducing the intensity of nocturnal light in development of premature infants. Infants to the LDC gained weight earlier, compared with those randomized to CBL, and had a significant reduction in length of hospital stay. These results highlight those premature infants subjected to a LDC exhibit improvements in physiological development, favoring earlier weight gain and consequently a decrease in hospital stays. ClinicalTrials.gov; 02/09/2020 ID: NCT05230706.

Development of the circadian system and relevance of periodic signals for neonatal development.

Circadian rhythms are generated endogenously with a period of approximately 24h. Studies carried out during the last decade indicate that the circadian system develops before birth, and that the suprachiasmatic nucleus, a structure that is considered the mammalian circadian clock, is present in primates from the middle of pregnancy. Recent evidence shows that the infants' circadian system is sensitive to light from very early stages of development; it has also been proposed that low-intensity lighting can regulate the developing clock. After birth there is a progressive maturation of the outputs of the circadian system with marked rhythms in sleep-wake phenomena and hormone secretion. These facts express the importance of circadian photic regulation in infants. Thus, the exposure of premature babies to light/dark cycles results in a rapid establishment of activity/rest patterns, which are in the light-dark cycle. With the continuous study of the development of the circadian system and the influence on human physiology and disease, it is anticipated that the application of circadian biology will become an increasingly important component in the perinatal care.

Enfermedad pulmonar obstructiva crónica (EPOC). Bases para el médico general / Chronic Obstructive Pulmonary Disease (COPD). Bases for the General Practitioner

Resumen La enfermedad pulmonar obstructiva crónica (EPOC) es una enfermedad crónico-degenerativa frecuente, prevenible y tratable, caracterizada por persistentes síntomas respiratorios y limitación del flujo aéreo. En 2016, el Instituto Nacional de Enfermedades Respiratorias (INER) la ubicó en el cuarto lugar en la tabla de morbi-mortalidad anual en México. Su prevalencia está directamente relacionada con la del tabaquismo; sin embargo, su desarrollo es multifactorial. Para el estudio de la EPOC es importante conocer los antecedentes de exposición a factores de riesgo y la presencia de los principales síntomas; es esencial una historia clínica bien detallada, donde se recabe la mayor cantidad de datos de todo nuevo paciente en el que se conozca o se sospeche de la enfermedad, así como una espirometría para establecer el diagnóstico. Debido a la gran variabilidad que existe entre los pacientes con EPOC, es necesario establecer tratamiento farmacológico individualizado. Los fármacos utilizados en su tratamiento reducen los síntomas, la frecuencia y la gravedad de las exacerbaciones; sin embargo, no hay ningún medicamento que modifique el deterioro a largo plazo de la función pulmonar. Por lo tanto, el conocimiento básico de este padecimiento por el médico de primer contacto es esencial para la sospecha en una etapa inicial, y así ofrecer al paciente una intervención médica inmediata. El presente trabajo tiene la finalidad de acercar al médico general una visión básica de la EPOC.

Abstract Chronic obstructive pulmonary disease (COPD) is a chronic degenerative disease. It is a frequent, preventable and treatable disease characterized by persistent respiratory symptoms and airflow limitation. The National Institute of Respiratory Diseases (INER), ranked COPD in 2016 in fourth place in the table of annual morbidity and mortality in Mexico. The prevalence of COPD is directly related to smoking; however, its development is multifactorial. For its study it is important to know of any prior exposure to risk factors and of any manifestation of the main symptoms. To make a diagnosis, a detailed clinical history, where the largest amount of data is collected from every new possible COPD patient, and a spirometry are essential. Individual pharmacological treatment is necessary due to the great variability among COPD patients. The drugs used in the treatment of COPD reduce the symptoms, the frequency and severity of exacerbations; however, there is no medication that modifies the long-term deterioration of the lung function. Therefore, a basic knowledge of this condition by the medical doctor first contacted, is essential for the suspicion of COPD in its initial stage and thus, offer the patient immediate medical intervention. The objective of the present work is to provide a basic overview of COPD to the general practitioner.

A light/dark cycle in the NICU accelerates body weight gain and shortens time to discharge in preterm infants.

BACKGROUND: Bright constant light levels in the NICU may have negative effects on the growth and development of preterm infants OBJECTIVE: The aim of this study is to evaluate the benefits of an alternating light/dark cycle in the NICU on weight gain and early discharge from the therapy in premature infants. PATIENTS AND METHODS: A randomized interventional study was designed comparing infants in the NICU of Hospital Juarez de México, exposed from birth either to an LD environment (LD, n=19) or to the traditional continuous light (LL, n=19). The LD condition was achieved by placing individual removable helmets over the infant's heads. Body weight gain was analyzed, as the main indicator of stability and the main criteria for discharge in preterm infants born at 31.73±0.31week gestational age. RESULTS: Infants maintained in an LD cycle gained weight faster than infants in LL and therefore attained a shorter hospital stay, (34.37±3.12 vs 51.11±5.29days; P>0.01). Also, LD infants exhibited improved oxygen saturation and developed a daily melatonin rhythm. CONCLUSIONS: These findings provide a convenient alternative for establishing an LD environment for preterm healthy newborns in the NICU and confirm the beneficial effects of an alternating LD cycle for growth and weight gain and for earlier discharge time. Here we provide an easy and practical alternative to implement light/dark conditions in the NICU.

Leiomioma con extensión intracardiaca que condiciona insuficiencia cardiaca aguda: Reporte de caso / Leiomyoma with intracardiac extensión leading to acute heart failure: (case report)

Son raros los casos de leiomiomas intravenosos con extensión intracardiaca. En pacientes con manifestaciones de sobrecarga de cavidades derechas o quienes debutan con síntomas de insuficiencia cardiaca aguda y cuyos síntomas no mejoran con el manejo convencional, se debe considerar esta entidad, y es importante evaluar de forma integral con estudios de gabinete como electrocardiograma, ecocardiograma, tomografía o resonancia magnética. Reportamos el caso de una mujer de 46 años que manifiesta síntomas de insuficiencia cardiaca aguda e inadecuada respuesta a los fármacos convencionales. Con hallazgos ecocardiográficos de tumoración en atrio derecho que protruye a ventrículo derecho y causa insuficiencia tricuspídea. Por estudio tomográfico se confirma la extensión del tumor a vena cava inferior y ventrículo derecho; se resuelve de forma quirúrgica con resección radical y se confirma la extirpación histológica mediante estudio anatomopatológico.

Cases of intravenous leiomyoma with intracardiac extension are rare. Patients with signs of right-sided overload who present symptoms of acute heart failure and whose symptoms do not improve with conventional management, we must consider this entity. It is important to comprehensively assess with imaging studies such as electrocardiogram, echocardiogram, Tomography (CT scan) or magnetic resonance. The following is a report of the case of a 46 year old woman with symptoms of acute heart failure and inadequate response to conventional drugs. The echocardiographic show findings of a tumor in the right atrium, protruding to the right ventricle causing tricuspid regurgitation. The CT scan confirmed the extent of the tumor to the inferior vena cava and right ventricle, and was resolved surgically with radical resection and histology lineage confirmed by pathologic examination.

Desarrollo de los ritmos biológicos en el recién nacido. Cátedra Especial "Dr. Ignacio Chávez" / Development of biological rhythms in the newborn child

Los ritmos circadianos se generan de forma endógena con un período de aproximadamente 24 h. Estudios realizados durante la última década indican que el sistema circadiano se desarrolla antes del nacimiento y que el núcleo supraquiasmático, estructura que se considera el reloj circadiano del mamífero, está presente en los primates desde la mitad de la gestación. Evidencias recientes muestran que el sistema circadiano de los infantes es sensible a la luz desde etapas muy tempranas del desarrollo; también se ha propuesto que la iluminación de baja intensidad puede regular el reloj en desarrollo. Después del nacimiento se presenta una maduración progresiva de las salidas del sistema circadiano con marcados ritmos en los fenómenos de sueño-vigilia y secreción de hormonas. Estos hechos expresan la importancia de la regulación fótica circadiana en los lactantes. Así, la exposición de los bebés prematuros a ciclos de luz/oscuridad tiene como resultado un rápido establecimiento de patrones de actividad/reposo, los que se encuentran en el ciclo luz-oscuridad. Con el continuo estudio del desarrollo del sistema circadiano y la influencia sobre la fisiología humana y la enfermedad, se prevé que la aplicación de la biología circadiana se convertirá en un componente cada vez más importante en la atención neonatal.

Circadian rhythms are endogenously generated with a period length of approximately 24 hours. Studies performed during the past decade indicate that the circadian timing system develops prenatally and the suprachias-matic nucleus, considered the site of the circadian clock, is present by midgestation in primates. Recent evidence also shows that the circadian system of primate infants is responsive to light since very early stages of development and that low-intensity lighting can regulate the developing clock. After birth, there is progressive maturation of the circadian system outputs, with pronounced rhythms on sleep-wake phenomena and hormone secretion; showing the importance of photic regulation on infants. Thus, exposure of premature infants to light/dark cycles results in the fast establishment of rest-activity patterns, which are in phase with the light-dark cycle. The continual study of circadian system development and its influence on human physiology and illness, it is foreseen that the application of circadian biology will become increasingly important for neonatal care.

Trastornos temporomandibulares: Complejo clínico que el médico general debe conocer y saber manejar. Cátedra especial "Dr. Ignacio Chávez" / Temporomandibular disorders: Clinical complex that the general practitioner must recognize and know how to treat. Special professorship "Dr. Ignacio Chávez"

Los trastornos temporomandibulares (TTM), abarcan un conjunto de problemas clínicos que comprometen diferentes estructuras anatómicas como son: músculos de la masticación, la articulación temporomandibular y estructuras asociadas. Se consideran como una subclasificación de desórdenes musculoesqueléticos y han sido identificados como una causa importante de dolor en la región facial de origen no dentario. Los trastornos temporomandibulares se caracterizan clínicamente por dolor en músculos de la masticación, área preauricular o directamente en la articulación (usualmente agravado por la manipulación y alteración de los movimientos mandibulares principalmente debido a limitación del movimiento), presencia de ruidos articulares como crepitación y chasquidos (clicking). Epidemiológicamente la prevalencia va del 20 al 70% en la población general, motivo por el que creemos que es importante que el médico general tenga el conocimiento básico sobre estos trastornos que generalmente los desconoce y los delega al médico odontólogo. El tratamiento de los TTM va desde fomentar el autocuidado, tratamiento conservador y, de ser necesario, tratamiento quirúrgico.

Temporomandibular disorders (TMDs) are a set of clinical problems that involve different anatomical structures such as masticatory muscles, the temporomandibular joint and related anatomical structures. They are considered a subclass of musculoskeletal disorders and have been identified as a major cause of non-dental facial pain. TMDs are characterized by pain in the masticatory muscles, either in the pre-auricular area or directly in the joint (usually worsened by manipulation or altered movement of the jaw, mainly due to movement limitation) and the presence of clicking sounds during movement. Epidemiologically, TMDs have a prevalence ranging from 20% to 70% in the general population, that is why we believe it is important for the general practitioner to have the basic knowledge about these disorders, often unknown to the general practitioner who leaves the to the odontologist. Treatment includes fostering self-care measures, conservative treatment, or surgical treatment when necessary.

Fisura facial nasoorbitaria, Tessier número 3 / Naso-orbital cleft, Tessier Number 3

Las fisuras oblicuas faciales son anormalidades poco frecuentes, aunque la incidencia exacta es desconocida, se reporta una incidencia de 1.5 a 5 por 100,000 nacimientos. Tessier en 1976 propuso una clasificación de las fisuras faciales, craneofaciales y laterofaciales. Morian describió la fisura oral nasoorbitaria (fisura número 3), que representa una de las malformaciones más difíciles de corregir para el cirujano plástico y reconstructivo. Reportamos un caso de fisura craneofacial Tessier número 3 así como la técnica de corrección quirúrgica empleada. Los autores enfatizan en el análisis de la embriología facial.

The oblique facial clefts are extremely rare facial anomalies, although the exact incidence of these facial clefts is unknown, is reported an incidence de 1.5 to 5 per 100,000 births. Tessier in 1976 proposed an anatomic classification of the facial, craniofacial, and laterofacial clefts. Number 3 clefts o oral-nasal-ocular cleft was described by Morian and represents one of the most difficult malformations to correct for the reconstructive surgeon. We report a case of unilateral Tessier No 3 craniofacial cleft and our approach to surgical correction. The authors emphasize in the analysis of the facial embryology.

Envejecimiento de un reloj (cronobiología de la vejez) / Ageing of a clock (cronobiology of old age)

El envejecimiento es el conjunto de modificaciones morfológicas y fisiológicas generadas como consecuencia de la acción del tiempo sobre los seres vivos. Entre estas modificaciones se debe de incluir la incapacidad de adaptación y de responder a los cambios medioambientales, por cada uno de los órganos, aparatos y sistemas. El envejecimiento de los organismos, y particularmente del hombre, es motivo de preocupación desde hace años debido a que nuestra expectativa de vida ha aumentado significativamente y este hecho ha acrecentado el número de habitantes con problemas de envejecimiento, que presentan procesos de deterioro paulatino de órganos y sus funciones asociadas. Muchas enfermedades, entre ellas ciertos tipos de demencia, enfermedades articulares, cardíacas y algunos tipos de cáncer, han sido asociados al proceso de envejecimiento. Uno de los trastornos más notorios en la senectud es la alteración del ritmo de sueño-vigilia, reflejo de un mal funcionamiento del reloj biológico y en consecuencia del sistema circadiano. En este escrito se abordan las bases fisiológicas de la desincronización interna que sufre el hombre en edad adulta así como sus consecuencias fisiológicas y algunas recomendaciones para coadyuvar al tratamiento de este trastorno.

Aging is the set of morphological and physiological changes generated by the action of time on living beings. These changes include the inability to adapt and respond to environmental challenges, by organs, apparatus and systems. Aging of organisms and particularly of man, has become a concern in recent years, because our life expectancy has increased significantly and this has increased the number of individual ailing from the effects of aging, which includes a series of processes of gradual deterioration of organs and their associated functions. Many diseases, such as dementia, joint disease, cardiovascular disease and some cancers have been associated with the aging process. One of the most notorious disorders in aged people is the alteration of the sleep-wake rhythm, a reflection of a malfunctioning biological clock and thus of the circadian system. This manuscript addresses the physiological basis and consequences of internal desynchronization suffered by aged people and numbers recommendations for the treatment of this disorder.

Anatomical reasons for the discrepancies in atrioventricular block after inferior myocardial infarction with and without right ventricular involvement.

The incidence of arrhythmias after acute myocardial infarction of the inferior wall varies with the affected segment and increases when there is right ventricular involvement. This paper provides a clear review of the blood supply to the conduction system and gives an anatomic explanation of that supply.We dissected 20 human hearts after anterograde and retrograde injection of latex. In every heart, we dissected the conduction system and its blood supply. Retrograde perfusion enabled proper injection of the atrial vessels that originate at the beginning of the coronary trunks.We describe the 4 main arteries that supply blood to the conduction system. The classic concept included the atrioventricular node artery and the 1st septal artery. To that we add Kugel's artery and the right superior descending artery.The incidence of arrhythmias after acute myocardial infarction of the inferior wall is greater when the occlusion of the coronary trunk is at or near the origin. This is due to the existence of the right superior descending artery, which is given off by the right coronary trunk less than 1 cm from the origin. The arrhythmias caused by the occlusion of the circumflex artery are due to the existence of Kugel's artery, which displays a peculiar anastomotic pattern.