Objective: Despite over 50 years of research on the physiological effects of sustained bed rest, data characterizing its effects on sleep macrostructure and breathing stability in humans are scarce. This study was conducted to determine the effects of continuous exposure to hypoxia and sustained best rest, both individually and combined, on nocturnal sleep and breathing stability. Methods: Elev...

abstract  introduction: hypertension is a very common cardiovascular disease with extensive effects on body organs. this study was conducted to compare the extent of target organ damage in hypertensive patients with and without significant nocturnal fall in blood pressure (dippers and non-dippers, respectively). methods: one-hundred patients with recently diagnosed hypertension underwent 24-hou...

Objectives Sleeping ecology plays a key integrative role in the primates' lives. Selecting an adequate sleeping site is therefore critical, but both extrinsic (e.g., predation, thermoregulation) and intrinsic factors body size, circadian activity) need to be considered simultaneously. There is, however, notable lack of comprehensive comparative analyses within primates. We explored links among ...

The mammalian circadian system synchronizes daily timing of activity and rest with the environmental light-dark cycle. Although the underlying molecular oscillatory mechanism is well studied, factors that influence phenotypic plasticity in daily activity patterns (temporal niche switching, chronotype) are presently unknown. Molecular evidence suggests that metabolism may influence the circadian...

Many species of migratory birds migrate in a series of solitary nocturnal flights. Between flights, they stop to rest and refuel for the next segment of their journey. The mechanism controlling this behaviour has long remained elusive. Here, we show that wild-caught migratory redstarts (Phoenicurus phoenicurus) are consistent in their flight scheduling. An advanced videographic system enabled u...

The mechanism of resting or nocturnal angina relative to primary alterations in myocardial oxygen supply or demand (MVO2) is still uncertain. We studied 23 patients (15 males, eight females, ages 45-83 years) with coronary artery disease (CAD) and rest angina using electrocardiographic and hemodynamic monitoring by intra-arterial line and Swan-Ganz thermodilution catheter. Data were recorded co...

Measurement of the circadian rest-activity cycle in a patient with early-onset Alzheimer disease for 555 days revealed marked changes in the timing and amount of nocturnal activity. After neuroleptic medication was changed to haloperidol, the rest-activity cycle became completely arrhythmic for two months, concomitant with a marked worsening of cognitive state. Circadian integrity returned toge...

OBJECTIVES Chronic heart failure is closely related to impaired cardiorespiratory reflex control, including decreased ventilatory efficiency during exercise (Ve/Vco(2)-slope) and central sleep apnea (CSA). Continuous positive airway pressure (CPAP) and nocturnal oxygen therapy alleviate CSA. The aim of the present study was to compare the effects of nocturnal CPAP and oxygen therapy on Ve/Vco(2...

It is known beneficial effect of essential tryptophan on nocturnal sleep. Its application in the field of infant nutrition is utilized to improve the rest of children with sleep problems. The development of infants’ cereals enriched with essential amino acid tryptophan this mainly for making dinner, have shown satisfactory results in tests with such children. We cannot forget that besides the a...

It is known beneficial effect of essential tryptophan on nocturnal sleep. Its application in the field of infant nutrition is utilized to improve the rest of children with sleep problems. The development of infants’ cereals enriched with essential amino acid tryptophan this mainly for making dinner, have shown satisfactory results in tests with such children. We cannot forget that besides the a...