Search results for "circadian rhythm"
showing 10 items of 324 documents
Cardiac Remodeling According to the Nocturnal Fall of Blood Pressure in Hypertensive Subjects: The Whole Assessment of Cardiac Abnormalities in Non-D…
2021
Objective: Several epidemiological studies suggest that the preservation of the physiological circadian rhythm of blood pressure or its disruption affects the extent of the organ damage developed by the patient. If we classify the circadian rhythm of blood pressure into four nocturnal profiles, significant differences emerge in terms of organ damage burden and prognosis: reverse dippers have the worst prognosis while dippers and mild dippers fall into an intermediate risk range. The risk profile of extreme dippers is still debated, and the available data are very conflicting and inconclusive. Starting from this gap of knowledge, we aimed to evaluate, retrospectively, in a cohort of hyperten…
Morning and evening type: The cortisol awakening response in a sleep laboratory.
2019
Abstract Background Earlier evidence indicated an association between chronotype and the cortisol awakening response (CAR). However, these earlier data were collected without objective control for participant compliance being available, which, following recent guidelines, is considered critical for ensuring data validity. Here, we are seeking to replicate these earlier findings within a well-controlled sleep laboratory set up. Methods The sample consisted of 103 young males, including 12 participants defined as ‘evening’ (MEQ 59) types. All participants slept for one night in a sleep laboratory and were wakened at 6:30 AM the next morning. Saliva samples for the assessment of the CAR were…
Modification of Diurnal Cortisol Secretion in Women’s Professional Basketball. A Pilot Study
2021
Elite basketball training causes high levels of physiological stress, which can lead to negative physiological disorders in female athletes. The aim of this study was to establish the impact of physical activity on the rhythm of salivary cortisol secretion in elite female basketball players over one week. The population sample included 9 women professional basketball players. The control group was made up of 9 women who did not do any exercise. Saliva samples were collected from all participants at 9:00 a.m. and 11:00 p.m. on training days. Samples from the basketball group showed a significantly higher cortisol secretion. Moreover, from the second night, the pattern of cortisol secretion o…
Circadian rhythms and chemical carcinogenesis: Potential link. An overview.
2009
Circadian rhythm is an integral and not replaceable part of the organism's homeostasis. Its signalling is multidimensional, overlooking global networks such as chromatin remodelling, cell cycle, DNA damage and repair as well as nuclear receptors function. Understanding its global networking will allow us to follow up not only organism dysfunction and pathology (including chemical carcinogenesis) but well-being in general having in mind that time is not always on our side. The authors thank ECNIS (Environmental Cancer, Nutrition and Individual Susceptibility), a network of excellence operating within the European Union 6th Framework Program, Priority 5: Food Quality and Safety (Contract no. …
Identification of a gene overexpressed in aphids reared under short photoperiod.
2003
Most aphids develop a cyclic parthenogenesis life-cycle. After several generations of viviparously produced parthenogenetic females, follows a single annual generation of sexual individuals, usually in autumn, that mate and lay the sexual eggs. Shortening of photoperiod at the end of the summer (together with temperature) is a key factor inducing the sexual response. Currently no genes involved in the cascade of events that lead to the appearance of sexual forms have been reported. After a Differential Display RT-PCR survey performed on Acyrthosiphon pisum aphids, we identified a gene that is overexpressed in aphids reared under short photoperiod conditions that induce sexuality in this spe…
Alkylresorcinol Metabolites in Urine and Plasma as Potential Biomarkers of Rye and Wheat Fiber Consumption in Prostate Cancer Patients and Controls
2015
Alkylresorcinols (ARs) are phytochemicals mainly associated with rye/wheat bran. Plasma ARs and their plasma and urine metabolites are considered as biomarkers for whole-grain rye/wheat intake. However ARs metabolite day and night variations have not been studied in prostate cancer patients yet. We investigated ARs metabolites 3, 5-dihydroxy-benzoic acid (DHBA), and 3-(3, 5-dihydroxyphenyl)-1-propanoic acid (DHPPA) in urine and plasma in prostate cancer patients and in control group. DHPPA in 12-h overnight urine correlated with the intake of rye bread and bread fiber across short time periods (3 days). Plasma DHPPA concentration was significantly greater in the prostate cancer group than i…
How is the inner circadian clock controlled by interactive clock proteins?
2015
AbstractMost internationally travelled researchers will have encountered jetlag. If not, working odd hours makes most of us feel somehow dysfunctional. How can all this be linked to circadian rhythms and circadian clocks? In this review, we define circadian clocks, their composition and underlying molecular mechanisms. We describe and discuss recent crystal structures of Drosophila and mammalian core clock components and the enormous impact they had on the understanding of circadian clock mechanisms. Finally, we highlight the importance of circadian clocks for the daily regulation of human/mammalian physiology and show connections to overall fitness, health and disease.
No effects of pulsed radio frequency electromagnetic fields on melatonin, cortisol, and selected markers of the immune system in man.
2001
There is growing public concern that radio frequency electromagnetic fields may have adverse biological effects. In the present study eight healthy male students were tested to see whether or not radio frequency electromagnetic fields as used in modern digital wireless telecommunication (GSM standard) have noticeable effects on salivary melatonin, cortisol, neopterin, and immunoglobulin A (sIgA) levels during and several hours after exposure. In a specifically designed, shielded experimental chamber, the circularly polarized electromagnetic field applied was transmitted by an antenna positioned 10 cm behind the head of upright sitting test persons. The carrier frequency of 900 MHz was pulse…
Lighting in educational environments: An example of a complete analysis of the effects of daylight and electric light on occupants
2013
Abstract Light induces not only visual responses but also non-visual effects, indeed it affects performance, mood, attention and influences the synchronization of the biological clock. Duration, timing, intensity and the spectral power distribution of the light that reaches the eyes can have influence on human circadian rhythm and consequently on health. Given the important impact of the non-visual responses on people wellbeing, developing a model that allows lighting designers to predict them is a fundamental goal. In this paper a case study is reported: a series of measurements were carried out in a University classroom in order to study daylight and electric light characteristics and als…
Copper homeostasis influences the circadian clock in Arabidopsis.
2010
Almost every aspect of plant physiology is influenced by diurnal and seasonal environmental cycles which suggests that biochemical oscillations must be a pervasive phenomenon in the underlying molecular organization. The circadian clock is entrained by light and temperature cycles, and controls a wide variety of endogenous processes that enable plants to anticipate the daily periodicity of environmental conditions. Several previous reports suggest a connection between copper (Cu) homeostasis and the circadian clock in different organisms other than plants. However, the nature of the Cu homeostasis influence on chronobiology remains elusive. Cytosolic Cu content could oscillate since Cu regu…