The biological week and broader time structures (chronomes): in memory of Gunther Hildebrandt

Chronotherapeutic Approaches

The chapter provides a comprehensive review of current approaches to personalized chronodiagnosis and chronotherapy. We discuss circadian clock drug targets that aim to affect cellular clock machinery, circadian mechanisms of pharmacokinetics/pharmacodynamics, and chronotherapeutic approaches aimed at increasing treatment efficacy and minimizing its side effects. We explore how chronotherapy can combat acquired and compensatory drug resistance. Non-pharmacological interventions for clock preservation and enhancement are also overviewed, including light treatment, melatonin, sleep scheduling, time-restricted feeding, physical activity, and exercise.

Some Near- and Far-Environmental Effects on Human Health and Disease with a Focus on the Cardiovascular System

Environmental effects on human physiopathology are revisited herein from a chronobiologic viewpoint, with a focus on the cardiovascular system. Physiological variables undergo recurring changes that are predictable in a statistical, albeit not deterministic way. Biological rhythms cover a broad range of frequencies, which are usually shared by the environment as "co-periodisms". Some of these photic and non-photic periodicities shared by the environment and physiopathology are reviewed herein, together with their possible underlying mechanisms. A plausible cascade of events from the long-period cycles found in the cosmic environment to those affecting the Earth's atmosphere and weather conditions is presented, which may shed light on how they may shape the cycles characterizing human health. Maps of important cycles shared between the environment and physiopathology are being catalogued in an atlas of chronomes with the goal of distinguishing between strong and weak associations and providing an estimate of the lag that can be anticipated before observing physiological changes.

Immediate and delayed incorporations of events into dreams: further replication and implications for dream function

The incorporation of memories into dreams is characterized by two types of temporal effects: the day-residue effect, involving immediate incorporations of events from the preceding day, and the dream-lag effect, involving incorporations delayed by about a week. This study was designed to replicate these two effects while controlling several prior methodological problems and to provide preliminary information about potential functions of delayed event incorporations. Introductory Psychology students were asked to recall dreams at home for 1 week. Subsequently, they were instructed to select a single dream and to retrieve past events related to it that arose from one of seven randomly determined days prior to the dream (days 1-7). They then rated both their confidence in recall of events and the extent of correspondence between events and dreams. Judges evaluated qualities of the reported events using scales derived from theories about the function of delayed incorporations. Average ratings of correspondences between dreams and events were high for predream days 1 and 2, low for days 3 and 4 and high again for days 5-7, but only for participants who rated their confidence in recall of events as high and only for females. Delayed incorporations were more likely than immediate incorporations to refer to events characterized by interpersonal interactions, spatial locations, resolved problems and positive emotions. The findings are consistent with the possibility that processes with circaseptan (about 7 days) morphology underlie dream incorporation and that these processes subserve the functions of socio-emotional adaptation and memory consolidation.

Chronoecoepidemiology of "strain": infradian chronomics of urinary cortisol and catecholamines during nightly exposure to noise

This meta-analysis of published data (Noise Health 5 (2002) 35 and 47) summarizing a survey for 40 days of the nightly excretion of urinary free cortisol, epinephrine and norepinephrine validates a circaseptan cortisol pattern anticipated and reported earlier for cortisol, here not detected for the catecholamines. We also quantify a circadecan (about 10-day) variation in nightly norepinephrine excretion, but not in the excretion of the other two hormones examined. About 4.2-day variations, common to norepinephrine and epinephrine, and an about 4.7-day variation in cortisol await further scrutiny, since these components were not anticipated. Infradian characteristics are quantified time-microscopically and differences among infradian aspects of the spectral element of endocrine chronomes (time structures; from chronos, time and nomos, rule) are demonstrated. Chronomics, the cartography of chronomes, reveals that "stress hormones" need to be examined separately in a budding chronoepidemiology seeking to detect how humans interact, mostly for better, sometimes for worse, with the undesirable features of the technology they create and of its consequences, such as aircraft noise.

Circaseptan aspects of self-assessed sleep protocols covering 70 nights on 33 clinically healthy persons

This study aimed to describe quantitatively some changes in sleep behavior. During 70 consecutive nights, 28 women and 3 men, 30 to 40 years of age and presumably clinically healthy, recorded the time of each awakening. Time of falling asleep were estimated from markings at 10-min. intervals from the times of lying down to sleep as an indication that the subject had not yet fallen asleep. Sleep duration and an index of effective sleep derived therefrom were analyzed by rhythmometric methods. On a group basis, anticipated components with periods of 1 and 0.5 wk., synchronized with the social schedule, were detected with statistical significance. Until long-term polysomnographic monitoring can readily cover the week automatically rather than only one or a few daily sleep spans, the self-monitoring of sleep behavior, yielding the circaseptan endpoints derived herein, may serve as a cost-effective tool in sleep research. By virtue of their relative simplicity, they could be part of a protocol designed to assess pharmacologic or nonpharmacologic interventions of sleep disturbance aimed at restoring undisturbed sleep.

Infradian, notably circaseptan testable feedsidewards among chronomes of the ECG and air temperature and pressure

To study the interactions among the natural physical environmental cycles and human infradian components of heart rate (HR) and HR variability (HRV), a healthy 49-year-old man in Kiev, who had monitored his electrocardiogram (ECG) around the clock earlier for 50 days, added at a later date with the same ambulatorily wearable device, a record of 70 days. The mean value of the R-R intervals (R-R), their standard deviation (SDNN) and other HRV endpoints, computed over consecutive 5-min intervals, served as markers of the subject's functional associations with the amplitude of fluctuations in atmospheric pressure (FAP) and the planetary Kp index of geomagnetic disturbance. About-weekly and half-weekly cycles in HRV endpoints indicate a reduction in physiological 'preparedness', here described as 'dynamics', of the subject investigated on Saturdays and Sundays and a sharp increase in 'dynamics' on Mondays. The waveform of the weekly oscillation seemed to be influenced by ambient air temperature and FAP. On Mondays, an FAP amplification or a temperature rise was accompanied by a significant decrease in R-R and SDNN, indicating an aggravation of a 'Monday effect' in physiological 'dynamics'. HRV endpoints also revealed about-5-day and about-12-day cyclic components similar to those found in FAP. The infradian pattern in a 70-day record differed from one found earlier in a 50-day record of the same subject. Changes in the natural physical environment (past as well as present), especially in air temperature and FAP, likely influence(d) if not synchronize(d) the amplitude and waveform of infradian weekly and half-weekly physiological cycles. Some of these infradians, their wobbly nature notwithstanding, may have been built into our temporal make-up by an evolutionary integration of life in the non-stationary quasi-periodic natural physical environment, which continues to contribute to variability.

The week, inherited in neonatal human twins, found also in geomagnetic pulsations in isolated Antarctica

About 7-day (circaseptan) components, found at different levels of organization, notably in relation to growth, regeneration, repair and development, are often viewed as reflecting no more than the 7-day societal schedule, ample evidence for a built-in feature notwithstanding. Herein, we resolve circaseptans in geomagnetic pulsations recorded by a stand-alone magnetometer residing in Antarctica, far away from societal influences. Human physiological data, collected in the neonatal intensive care unit, show by intra-class correlation analysis that the nonlinearly assessed circaseptan period of heart rate, diastolic blood pressure and body weight is more similar between same-gender twins than among twin pairs, lending additional support for the endogenicity of circaseptans. Like circadians, about-weekly features in environmental variables such as geomagnetic pulsations were genetically acquired in the course of evolution.