Juan Antonio Madrid

• University of Murcia

Introduction The interplay among sleep patterns, social habits and environmental cues is becoming increasingly more important for public health and wellbeing due to its connection to circadian desynchronization. This paper explores said connections in Spain (which has an official and solar time mismatch), introducing the “Three Times Score” ‒which...

Background/Objectives: Many patients suffering from liver cirrhosis are eventually added to waiting lists for liver transplantation whose priority is established based on scales such as the Child–Pugh score. However, two marker rhythms of the circadian system, motor activity and distal temperature, are not evaluated. Methods: To determine the relat...

Circadian rhythm sleep–wake disorders (CRSWD) are sleep dysfunctions related to circadian functioning. They are characterized by symptoms of insomnia or excessive sleepiness that occur because the intrinsic circadian pacemaker is not entrained to a 24-h light/dark cycle. Affected individuals with a free-running disorder or hypernycthemeral syndrome...

Our biological processes do not present a static and steady picture. Instead, most of these processes oscillate throughout the 24-h day. The system that controls this circadian rhythmicity is composed of a central pacemaker and peripheral oscillators that rely on inputs and produce outputs that can be measured through appropriate techniques. The co...

Introduction Prolonged social isolation is a form of passive chronic stress that has consequences on human and animal behavior. The present study was undertaken to elucidate whether the long-term isolation would precipitate age-related changes in anxiety and spatial learning and memory in degus. Methods We investigated the effects of long-term soc...

Simple Summary Human rhythmicity is subjected to the workings of the internal circadian clock, but it is also influenced by environmental time (mainly the light-dark cycle) and social timing imposed by the official time at our location, as well as by our work schedule. When a misalignment among these times occurs, an internal order impairment appea...

Citation: Bonmatí-Carrión, M.-Á.; Casado-Ramirez, E.; Moreno-Casbas, M.-T.; Campos, M.; ModulEN Consortium; Madrid, J.A.; Rol, M.-A.

Purpose of Review Circadian rhythms impose daily rhythms a remarkable variety of metabolic and physiological functions, such as cell proliferation, inflammation, and DNA damage response. Accumulating epidemiological and genetic evidence indicates that circadian rhythms’ disruption may be linked to cancer. The integration of circadian biology into c...

The main aim of this international consensus document on obstructive sleep apnea is to provide guidelines based on a critical analysis of the latest literature to help health professionals make the best decisions in the care of adult patients with this disease. The expert working group was formed primarily of 17 scientific societies and 56 speciali...

The main aim of this international consensus document on obstructive sleep apnea is to provide guidelines based on a critical analysis of the latest literature to help health professionals make the best decisions in the care of adult patients with this disease. The expert working group was formed primarily of 17 scientific societies and 56 speciali...

Our aim was to evaluate the circadian rhythm of motor activity, body position and integrated variable TAP (composed by wrist Temperature, motor Activity and body Position) in Sleep Disordered Breathing (SDB), its relation to SDB severity and the effect of continuous positive airway pressure (CPAP) on these circadian rhythms. To do this, we monitore...

An appropriate exposure to the light-dark cycle, with high irradiances during the day and darkness during the night is essential to keep our physiology on time. However, considering the increasing exposure to artificial light at night and its potential harmful effects on health (i.e. chronodisruption and associated health conditions), it is essenti...

Eating chocolate in the morning or in the evening/at night, may differentially affect energy balance and impact body weight due to changes in energy intake, substrate oxidation, microbiota (composition/function), and circadian‐related variables. In a randomized controlled trial, postmenopausal females (n = 19) had 100 g of chocolate in the morning...

Octodon degus is primarily a diurnal species, however, in laboratory conditions, it can switch from diurnal to nocturnal in response to wheel running availability. It has been proposed that this activity inversion obeys thermoregulatory constraints induced by vigorous physical exercise. Thus, its activity shifts to the night as the ambient temperat...

It has been demonstrated that in adulthood rodents show newly born neurons in the subgranular layer (SGL) of the dentate gyrus (DG), and in the subventricular zone (SVZ). The neurons generated in the SVZ migrate through the rostral migratory stream (RMS) to the olfactory bulb. One of the markers of newly generated neurons is doublecortin (DCX). The...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

El objetivo principal de este Documento Internacional de Consenso (DIC) sobre Apnea Obstructiva del Sueño es proporcionar unas directrices que permitan a los profesionales sanitarios tomar las mejores decisiones en la asistencia de los pacientes adultos con esta enfermedad según un resumen crítico de la literatura más actualizada. El grupo de traba...

This study aimed to analyze the associations of activity‐rest pattern indicators with academic achievement, executive function, and intelligence and to explore whether these associations are mediated by the total gray matter volume among children with overweight/obesity. Ninety‐five children (10 ± 1 year, 37 girls) with overweight/obesity (based on...

We present evidence of pupil response modification, as well as differential theoretical melatonin suppression through selective and dynamic electrochromic filtering of visible light in the 400–500 nm range to minimize chronodisruptive nocturnal blue light exposure. A lower activation of intrinsically photosensitive retinal ganglion cells (ipRGCs),...

Chronotype has been mostly assessed with subjective scales. Objective assessment has been undertaken with actigraphy, although problems may occur in classifying chronotype. The aims of the study were to assess chronotype in school-age children using a novel integrative measurement (TAP) derived from non-invasive assessments of wrist temperature (T)...

Isolation from external time cues allows endogenous circadian rhythmicity to be demonstrated. In this study, also filmed as a television documentary, we assessed rhythmic changes in a healthy man time isolated in a bunker for 9 days/nights. During this period the lighting conditions were varied between: (1) self-selected light/dark cycle, (2) const...

Aging modifies not only multiple cellular and homeostatic systems, but also biological rhythms. The circadian system is driven by a central hypothalamic oscillator which entrains peripheral oscillators, in both cases underlain by circadian genes. Our aim was to characterize the effect of aging in the circadian expression of clock genes in the human...

The present study proposes a classification model for the differential diagnosis of primary insomnia (PI) and delayed sleep phase disorder (DSPD), applying machine learning methods to circadian parameters obtained from ambulatory circadian monitoring (ACM). Nineteen healthy controls and 242 patients (PI = 184; DSPD = 58) were selected for a retrosp...

In order to develop objective indexes for chronotype identification by means of direct measurement of circadian rhythms, 159 undergraduate students were recruited as volunteers and instructed to wear ambulatory circadian monitoring (ACM) sensors that continuously gathered information on the individual’s environmental light and temperature exposure,...

Modern 24h‐society lifestyle is associated with experiencing frequent shifts in the lighting conditions which can negatively impact human health. Here, we use the degus, a species exhibiting diurnal and nocturnal chronotypes, to: (i) assess the impact of chronic shifts of the light:dark (LD) cycle in the animal’s physiology and behaviour; (ii) test...

Conferencia presentada en la XII Reunión Científica sobre Atención (RECA 12), durante los días 3-5 octubre 2019, en Almería, España. Todos los materiales (diapositivas, texto y audio en vivo) están disponibles en Zenodo: https://zenodo.org/record/3474084

Integrated multispectral devices provide convenient means for assessing the inputs to the five known photoreceptors present in the human retina. These photoreceptors drive relevant visual and non-visual pathways that control key aspects of human physiology. In this Letter we show that standard metrics of retinal photoreceptoral exposure can be quan...

Background: Parkinson's disease (PD) is associated with α-synuclein (αS) aggregation within the enteric nervous system (ENS) and constipation. Squalamine displaces proteins that are electrostatically bound to intracellular membranes and through this mechanism suppresses aggregation of αS monomers into neurotoxic oligomers. Objective: We sought t...

During last decades, the way of life in modern societies has deeply modified the temporal adjustment of the circadian system, mainly due to the inappropriate use of artificial lighting and the high prevalence of social jet-lag. Therefore, it becomes necessary to design non-invasive and practical tools to monitor circadian marker rhythms but also it...

Chrononutrition, or the circadian timing of food intake, has proposed that nutrients, bioactive compounds, and foods modulate the peripheral clocks with implications on health. We evaluated the effects of the antioxidant dietary fiber from spent coffee grounds supplemented biscuits as a food ingredient (SCF-B), or a combination of spent coffee grou...

The development of wearable devices has increase interest in the use of ambulatory methods to detect sleep disorders more objectively than those permitted by subjective scales evaluating sleep quality, while subjects maintain their usual lifestyle. This study aims to validate an ambulatory circadian monitoring (ACM) device for the detection of slee...

After European Union decided to properly ask citizens about their feelings regarding Daylight Saving Time (DST), a small fraction of European citizens had told that they don't want to change the time twice a year. However, there are still misgivings about the biomedical and clinical meanings of this position and a consensus is lacking. An internati...

The pupillary light reflex (PLR) is a neurological reflex driven by rods, cones, and melanopsin-containing retinal ganglion cells. Our aim was to achieve a more precise picture of the effects of 5-min duration monochromatic light stimuli, alone or in combination, on the human PLR, to determine its spectral sensitivity and to assess the importance o...

The ageing process is associated with sleep and circadian rhythm (SCR) frailty, as well as greater sensitivity to chronodisruption. This is essentially due to reduced day/night contrast, decreased sensitivity to light, napping and a more sedentary lifestyle. Thus, the aim of this study is to develop an algorithm to identify a SCR phenotype as belon...

Adult Nothobranchius furzeri of the MZM-04/10 strain were individually kept and subjected to a "5 + 2" shifting lighting schedule (SHIFT) for 8 weeks in order to evaluate the desynchronizing effects of a simulated human-like shift-work schedule on the functioning of the circadian system (CS). With this aim, sixteen 21-week-old N. furzeri were place...

Attention maintenance is highly demanding and typically leads to vigilance decrement along time on task. Therefore, performance in tasks involving vigilance maintenance for long periods, such as driving, tends to deteriorate over time. Cognitive performance has been demonstrated to fluctuate over 24 h of the day (known as circadian oscillations), t...

Neurophysiological markers of the ability to sustain attention and exert inhibitory control of inappropriate responses have usually relied on neuroimaging methods, which are not easily applicable to real-world settings. The current research tested the ability of electroencephalographic and skin temperature markers to predict performance during the...

Parkinson’s disease (PD) is associated with several non-motor symptoms that may precede the diagnosis and constitute a major source of frailty in this population. The digital era in health care has open up new prospects to move forward from the qualitative and subjective scoring for PD with the use of new wearable biosensors that enable frequent qu...

Background & aims: While environmental factors are presumed to be primary drivers of food timing, preliminary evidence suggests that genetics may be an additional determinant. The aim was to explore the relative contribution of genetics and environmental factors to variation in the timing of food intake in a Spanish twin population. Because chrono...

Background & aims Assessment of circadian health is confined to adults. However, understanding circadian status of school-aged children is necessary due to its health implications. The aim was to develop 1) a protocol to assess circadian function in school-aged children by combining the best non-invasive tools previously validated in adults; 2) a s...

The central circadian pacemaker (Suprachiasmatic Nuclei, SCN) maintains the phase relationship with the external world thanks to the light/dark cycle. Light intensity, spectra, and timing are important for SCN synchronisation. Exposure to blue-light at night leads to circadian misalignment that could be avoided by using less circadian-disruptive wa...

Introduction The objective of the study was to evaluate sleep, circadian rhythms and neurocognitive status of high performance athletes during the usual period of training, competitions and studies. Materials and methods A team of 12 high-performance basketball players (women, 15–17 years old) concentrated in a sports residence was evaluated. Slee...

Siesta is a relevant aspect of sleep due to its posited relationship with health or cognitive function. However, unlike night-time sleep, studies about daytime-sleep determinants and characteristics are scarce, and the genetic/environmental structure of siesta is still unknown. Our aim was to explore the relative contribution of genetic and environ...

Vigilance usually deteriorates over prolonged driving at non-optimal times of day. Exposure to blue-enriched light has shown to enhance arousal, leading to behavioral benefits in some cognitive tasks. However, the cognitive effects of long-wavelength light have been less studied and its effects on driving performance remained to be addressed. We te...

Study objectives Our aim was to evaluate the circadian rhythm of distal skin temperature (DST) in Sleep Disordered Breathing (SDB), its relation to excessive daytime sleepiness and the effect of continuous positive airway pressure (CPAP) on DST. Methods Eighty SDB patients (53.1±1.2 years old, 27.6% women) and 67 healthy subjects (52.3±1.6 years o...

The aim of this work was to determine whether juvenile and adult European seabass (Dicentrarchus labrax L.), fed ad libitum manually and with self-feeding demand feeders, respectively, were able to discriminate between a fish oil-based diet and a series of diets made with vegetable oils (soybean, linseed, rapeseed and sunflower oil), as well as a f...

Propósito del estudio: Los relojes circadianos son bucles de retroalimentación molecular autónomos que se producen a nivel celular y generan ritmos diarios en la expresión de numerosos genes, funciones celulares, procesos fisiológicos y comportamiento. A medida que nuestro organismo envejece, el sistema circadiano sufre un deterioro que se manifies...

Background & aims: Chronobiology studies periodic changes in living organisms and it has been proposed as a promising approach to investigate obesity. We analyze the association of the characteristics of the rest-activity rhythms with obesity, cardiorespiratory fitness and metabolic risk in adolescents from nine European countries. Methods: 1044...

Urinary bladder function consists in the storage and controlled voiding of urine. Translational studies require animal models that match human characteristics, such as Octodon degus, a diurnal rodent. This study aims to characterize the contractility of the detrusor muscle and the morphology and code of the vesical plexus from O. degus. Body temper...

La Sociedad Española de Sueño tiene como uno de sus principales objetivos la promoción de un sueño saludable en la población general y profesionales de la salud. El presente documento pretende realizar una revisión de la literatura científica actual sobre hábitos de sueño que sirva de fundamento para establecer unas recomendaciones generales y útil...

Intrinsically photosensitive retinal ganglion cells (ipRGCs), whose photopigment melanopsin has a peak of sensitivity in the short wavelength range of the spectrum, constitute a common light input pathway to the olivary pretectal nucleus (OPN), the pupillary light reflex (PLR) regulatory centre, and to the suprachiasmatic nuclei (SCN), the major pa...

Chronobiology is the scientific discipline that deals with the study of the biological rhythms and their underlying mechanisms. The alteration of biological rhythms, such as blood pressure or temperature begins to be considered as a good marker of certain diseases and senescence. Among the variables, the wrist skin temperature has proven to be a go...

Delayed sleep wake phase disorder (DSWPD) or delayed sleep phase disorder is the most frequent circadian rhythm sleep disorder and is commonly seen in adolescents. DSWPD is characterized by habitual by sleep onset and wake times that are usually delayed more than two hours relative to conventional sleep-wake times. Clinically, affected subjects exp...

Objective The main objective of this study was to determine the relationship between the characteristics of nurses' work environments in hospitals in the Spanish National Health System (SNHS) with nurse reported quality of care, and how care was provided by using different shifts schemes. The study also examined the relationship between job satisfa...

Insomnia is very common during childhood (30% of children under 5), and causes a serious cognitive and emotional consequence in learning, as well as significant medical comorbidity. It also affects the quality of life, not only of the child, but also of the whole family. Paediatrician training in its diagnosis and treatment is usually poor. For thi...

In humans, insulin sensitivity varies according to time of day, with decreased values in the evening and at night. Mechanisms responsible for the diurnal variation in insulin sensitivity are unclear. We investigated whether human adipose tissue (AT) expresses intrinsic circadian rhythms in insulin sensitivity that could contribute to this phenomeno...

Background Adequate circadian timing of cancer treatment schedules (chronotherapy) can enhance tolerance and efficacy several-fold in experimental and clinical situations. However, the optimal timing varies according to sex, genetic background and lifestyle. Here, we compute the individual phase of the Circadian Timing System to decipher the intern...

Objective: The aim of the study was to investigate whether postmenopausal women show differences in circadian-related variables and sleep characteristics compared with premenopausal women, and to analyze potential associations between these circadian-related variables and abdominal fat distribution or metabolic syndrome (MetS) components. Methods...

At present, the measurement of circadian system status under free-living conditions by the use of sensors is a relatively new technique. The data obtained using these methods are influenced by strong environmental masking factors and artifacts that can affect its recording. Therefore, the use of integrative variables such as TAP, a measure that inc...

The confinement of critically ill patients in intensive care units (ICU) imposes environmental constancy throughout both day and night (continuous light, noise, caring activities medications, etc.), which has a negative impact on human health by inducing a new syndrome known as circadian misalignment, circadian disruption or chronodisruption (CD)....

Since there is less movement during sleep than during wake, the recording of body movements by actigraphy has been used to indirectly evaluate the sleep-wake cycle. In general, most actigraphic devices are placed on the wrist and their measures are based on acceleration detection. Here, we propose an alternative way of measuring actigraphy at the l...

In circadian terms, human ontogeny is characterized by the emergence of a daily pattern, from a previous ultradian pattern, for most variables during the first 6 months of life. Circadian aging in humans is characterized by a phase advance, accompanied by rhythm fragmentation and flattening. Despite an expanding body of literature focused on distal...

To evaluate the circadian system status of the subject may be of special interest in nutrition. Particularly for those studies related to the assessment of diseases related to malnutrition, as it is the case of most of the degenerative diseases such as obesity, cancer, or cardiovascular diseases. For this purpose, one of the approaches consists to...

Currently, in developed countries, nights are excessively illuminated (light at night), whereas daytime is mainly spent indoors, and thus people are exposed to much lower light intensities than under natural conditions. In spite of the positive impact of artificial light, we pay a price for the easy access to light during the night: disorganization...

Several studies have been performed to identify age-related changes in the circadian system (CS) but the impairment of the CS and its chronodisruption at the end of an organism life have not been studied in depth. Aging commonly affects the input pathways into the biological clock or restraints their processing, therefore simplifying the system out...

MÉXICO OBESO es una primera referencia para estudiantes, profesores, investigadores e interesados en indagar acerca de la obesidad y su compleja interacción con factores sociales, epidemiológicos, médicos, biológicos, nutricionales, psicológicos y educativos que han alarmado a todos los sectores de la sociedad de nuestro país. Para el resto del mun...

Sleep problems are highly prevalent among our children and adolescents. Its treatment is mainly based on cognitive behavioural therapies and habit modification procedures. However, the use of sleep promoting drugs and substances is widespread without being supported by clinical guidelines. Exogenous melatonin is a neurohormone marketed as a nutriti...

Background/objectives: Timing of food intake associates with body weight regulation, insulin sensitivity and glucose tolerance. However, the mechanism is unknown. The aim of this study was to investigate the effects of changes in meal timing on energy-expenditure, glucose-tolerance and circadian-related variables. Subjects/methods: Thirty-two wo...

Study objectives: To study the effect of melatonin administration on glucose metabolism in humans in the morning and evening. Design: Placebo-controlled, single-blind design. Setting: Laboratory assessments. Participants: 21 healthy women (24 ± 6 y; body mass index: 23.0 ± 3.3 kg/m(2)). Interventions: Glucose tolerance was assessed by oral...

Previous research shows that wrist temperature (WT) is a good marker to assess the circadian system health in different circumstances. However, no studies have been performed in order to know the genetic component of this circadian marker. For this purpose, the aim was to determine, using classical twin models, the relative genetic and environmenta...

. Patients with dementia, especially Alzheimer’s disease, present several circadian impairments related to an accelerated perturbation of their biological clock that is caused by the illness itself and not merely age-related. Thus, the objective of this work was to elucidate whether these circadian system alterations were already present in patient...

Background/objective: To evaluate the relation between docosahexaenoic acid (DHA) status and neurodevelopment in the offsprings of gestational diabetic mothers (ODMs). Subjects/methods: A prospective cohort study was performed. The offspring of 63 pregnant women (23 controls, 21 diet-controlled gestational diabetes mellitus (GDM) and 19 insulin-...