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saliva melatonin acrophase

Romesh G Abeysuriya, Steven W Lockley, Peter A Robinson, Svetlana Postnova
A biophysical model of the key aspects of melatonin synthesis and excretion has been developed, which is able to predict experimental dynamics of melatonin in plasma and saliva, and of its urinary metabolite 6-sulfatoxymelatonin (aMT6s). This new model is coupled to an established model of arousal dynamics, which predicts sleep and circadian dynamics based on light exposure and times of wakefulness. The combined model thus predicts melatonin levels over the sleep-wake/dark-light cycle and enables prediction of melatonin-based circadian phase markers, such as dim light melatonin onset (DLMO) and aMT6s acrophase under conditions of normal sleep and circadian misalignment...
May 2018: Journal of Pineal Research
M A Bonmati-Carrion, B Middleton, V L Revell, D J Skene, M A Rol, J A Madrid
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 level of the arm for joint evaluation of activity and body position. This method analyzes the tilt of three axes, scoring activity as the cumulative change of degrees per minute with respect to the previous sampling, and measuring arm tilt for the body position inference...
June 2015: Chronobiology International
Francine Harb, Maria Paz Hidalgo, Betina Martau
The diurnal light cycle has a crucial influence on all life on earth. Unfortunately, modern society has modified this life-governing cycle by stressing maximum production and by giving insufficient attention to the ecological balance and homeostasis of the human metabolism. The aim of this study is to evaluate the effects of exposure or lack of exposure to natural light in a rest/activity rhythm on cortisol and melatonin levels, as well as on psychological variables in humans under natural conditions. This is a cross-sectional study...
April 2015: Chronobiology International
Vural Fidan, Hamit Hakan Alp, Mustafa Gozeler, Onder Karaaslan, Omer Binay, Cemal Cingi
OBJECTIVE: Allergic rhinitis is an IgE-mediated inflammatory disease which effects 10%-50% of the normal population. The mechanism of its formation and the circadian rhythm of cortisol and melatonin in allergic rhinitis have not been investigated. STUDY DESIGN: Salivary levels of melatonin and cortisol were measured by radioimmunoassay in 35 newly diagnosed allergic rhinitis patients and in 23 control subjects matched for age and gender. RESULTS: In the study group; amplitude, baseline and peak levels of salivary melatonin were significantly decreased compared with healty controls (p<0...
September 2013: American Journal of Otolaryngology
Vural Fidan, Hamit Hakan Alp, Sadettin Kalkandelen, Cemal Cingi
PURPOSE: Extensive nasal polyposis is an inflammatory disease which effects 1%-4% of normal population. The mechanism of its formation and the circadian rhythm of cortisol and melatonin in ENP have not investigated. MATERIALS AND METHODS: Salivary levels of melatonin and cortisol were measured by radioimmunoassay in 31 patients with extensive nasal polyposis and in 27 control subjects matched for age and gender. In both groups none of the subjects did not have obstructive sleep apnea...
January 2013: American Journal of Otolaryngology
Marie Dumont, Hélène Blais, Joanie Roy, Jean Paquet
Circadian misalignment between the endogenous circadian signal and the imposed rest-activity cycle is one of the main sources of sleep and health troubles in night shift workers. Timed bright light exposure during night work can reduce circadian misalignment in night workers, but this approach is limited by difficulties in incorporating bright light treatment into most workplaces. Controlled light and dark exposure during the daytime also has a significant impact on circadian phase and could be easier to implement in real-life situations...
October 2009: Journal of Biological Rhythms
M Aoki, Y Yokota, T Hayashi, B Kuze, M Murai, K Mizuta, Y Ito
OBJECTIVES: Stress is involved in the development of symptoms of Meniere's disease (MD). Stress-related disease has been reported to be associated with disorders in the circadian rhythm of melatonin (MEL) which regulates that rhythm. We therefore investigated MEL circadian rhythm of patients with MD. PATIENTS AND METHODS: A comparison of 13 MD patients was made with age-matched controls. Saliva samples were collected every 3 h. A statistical analysis of the circadian rhythm of saliva MEL was performed for a circadian rhythm by the fit of a 24- and 12-h composite cosine model...
April 2006: Acta Neurologica Scandinavica
Ekkehardt-Siegfried Altpeter, Martin Röösli, Markus Battaglia, Dominik Pfluger, Christoph E Minder, Theodor Abelin
This paper describes the results of a unique "natural experiment" of the operation and cessation of a broadcast transmitter with its short-wave electromagnetic fields (6-22 MHz) on sleep quality and melatonin cycle in a general human population sample. In 1998, 54 volunteers (21 men, 33 women) were followed for 1 week each before and after shut-down of the short-wave radio transmitter at Schwarzenburg (Switzerland). Salivary melatonin was sampled five times a day and total daily excretion and acrophase were estimated using complex cosinor analysis...
February 2006: Bioelectromagnetics
J F Walters, S M Hampton, G A A Ferns, D J Skene
Although studies have reported the effects of the menstrual cycle on melatonin rhythmicity, none has investigated the effects of menopause on the melatonin rhythm. The circadian rhythm in melatonin and its relationship to subjective alertness was investigated in pre- and postmenopausal women under constant routine conditions (controlled posture, dim lighting, calorie intake, temperature, and prolonged wakefulness). Eleven healthy pre-menopausal (42+/-4 yr) and 10 postmenopausal women (55+/-2 yr) participated in the study...
2005: Chronobiology International
D F Kripke, S D Youngstedt, J A Elliott, A Tuunainen, K M Rex, R L Hauger, M R Marler
There is evidence that aging may impair phase-shifting responses to light synchronizers, which could lead to disturbed or malsynchronized circadian rhythms. To explore this hypothesis, 62 elder participants (age, 58 to 84 years) and 25 young adults (age, 19 to 40 years) were studied, first with baseline 1-wk wrist actigraphy at home and then by 72 h in-laboratory study using an ultra-short sleep-wake cycle. Subjects were awake for 60 minutes in 50 lux followed by 30 minutes of darkness for sleep. Saliva samples were collected for melatonin, and urine samples were collected for aMT6s (a urinary metabolite of melatonin) and free cortisol every 90 minutes...
2005: Chronobiology International
Zofia Ostrowska, Beata Kos-Kudła, Bogdan Marek, Dariusz Kajdaniuk, Kinga Wołkowska, Elzbieta Swietochowska, Janusz Górski, Bozena Szapska
Few reports, especially experimental ones indicate cause-effect connection between melatonin (Mel) and blood pressure. The aim of the study was to assess connection between a daily profile of Mel concentration in saliva and 24-hour cycle of blood pressure in 22 patients with moderate hypertension (12 men, 10 women), 20 patients with severe hypertension (9 men, 11 women) and 25 healthy subjects with normal blood pressure (13 men, 12 women). The age of studied subjects oscillated between 37 and 46 years. Concentrations of Mel were assessed in saliva collected during the day with intervals of 3 hours with the use of RIA method...
July 2004: Polski Merkuriusz Lekarski: Organ Polskiego Towarzystwa Lekarskiego
Guang-he Fei, Rong-yu Liu, Zhi-hong Zhang, Jiang-ning Zhou
AIM: To investigate the possible relationships between alterations in circadian rhythm of melatonin, cortisol and bronchial asthma. METHODS: Salivary melatonin and cortisol were measured simultaneously by radioimmunoassay in 10 mild intermittent or persistent patients, 11 moderate-to-severe persistent asthma patients, and 15 control subjects. Twelve salivary samples were collected in a series during a 24-h period in each subject. RESULTS: The results showed overall lower levels of salivary melatonin in asthma patients compared with control subject (P<0...
May 2004: Acta Pharmacologica Sinica
G Mitsutake, K Otsuka, G Cornélissen, M Herold, R Günther, C Dawes, J B Burch, D Watson, F Halberg
The aim of this study was to assess any variation in positive, negative and total affect recorded longitudinally; to compare the results with those from prior transverse or hybrid population studies, based on the same or a different method of mood rating; and to test for any association of mood with cardiovascular, hormonal and geophysical variables monitored concomitantly. The study approach was as follows. A clinically healthy 34-year-old man filled out the positive and negative affective scale (PANAS) questionnaire five times a day for 86 days...
2001: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
K Blazejová, S Nevsímalová, H Illnerová, I Hájek, K Sonka
The aim of our study was to assess the prevalence of the specific disorders of the circadian rhythm of cortisol and melatonin in the patients with sleep disorders. The group of our patients consisted of 93 persons (25 men, 68 women), from 4-72 years (mean age 38.3 years) with a sleep disorders. These patients were studied on Department of Neurology of 1st Medical Faculty of Charles University in Prague during years 1997-1999. Patients were divided by the clinical diagnosis into many subgroups: idiopathic hypersomnia (IH) 24 patients and other hypersomnias 8, narcolepsy 22, degenerative disorders 9, delay sleep phase syndrome (DSPS) 7, periodic leg movements syndrome (PLMS) 6, insomnia 7 and Parkinson's disease 10 patients...
2000: Sborník Lékar̆ský
Z Ostrowska, B Kos-Kudla, B Marek, E Swietochowska, J Górski
BACKGROUND: Few experimental and clinical studies show that melatonin (MEL) can play a significant part to modulate circadian bone metabolism. On this basis it was suggested that MEL secretion which altered during 24-h in obese women could be of importance to regulate bony mass defect after menopause. OBJECTIVE: The aim of the study was to prove if there were any connection between changes in 24-h profile of serum MEL levels and circadian metabolism of type I collagen in postmenopausal women with visceral obesity...
April 2001: Neuro Endocrinology Letters
A Voultsios, D J Kennaway, D Dawson
There are many situations in which it would be useful to know the phase state of the biological clock. It is recognized that measurement of melatonin levels can provide this information, but traditionally blood has been used for the analysis, and there are many problems in extending the measurements into the home or field situations. The aim of this study was to develop and validate a salivary melatonin radioimmunoassay and to compare results obtained against a plasma assay for determining the onset of melatonin secretion...
October 1997: Journal of Biological Rhythms
M Koller, M Kundi, H G Stidl, T Zidek, M Haider
Light exposure was measured in six day and six night watches (working 12-hour shifts five days in a row) during 48 h on work days and 48 h on days off using a photocell with a sensitivity corresponding to photopic vision. The photocell was mounted on a frame of spectacles, thus measuring in viewing direction. Light exposure was low both in night and day watches; however, in night watches exposures were significantly lower: On work days, night watches spent a mean of 13 min above 1,500 lx, day watches 52 min; on days off, night watches spent 3 min above 1,500 lx but day watches 89 min...
April 1993: Chronobiology International
S J Deacon, J Arendt
OBJECTIVES: Shift work and rapid travel across several time zones leads to desynchronization of internal circadian rhythms from the external environment and from each other with consequent problems of behaviour, physiology and performance. Field studies of travellers and shift workers are expensive and difficult to control. This investigation concerns the simulation of such rhythm disturbance in a laboratory environment. The main objectives are to assess the ability of controlled exposure to moderately bright light and darkness/sleep to delay circadian rhythms in volunteers without environmental isolation and, secondly, to evaluate the use of different indices of melatonin (MT) secretion together with self-rated alertness as marker rhythms...
March 1994: Clinical Endocrinology
M Härmä, J Laitinen, M Partinen, S Suvanto
The effects of four-day round flights (Helsinki-Los Angeles-Seattle-Helsinki) were studied on the circadian rhythms of salivary melatonin (MT) and cortisol (COR) in 35 flight attendants. The mean age of the subjects was 33 +/- 7 years (median 34, range 21-50). Five 24 h profiles of unstimulated saliva were collected at 2 h intervals (except at 04:00) before, during, and after the four day flight. Salivary MT and COR were determined by radioimmunoassay. Both MT and COR exhibited a clear circadian rhythm with acrophases before the flight at 03:03 (MT) and 09:08 (COR)...
September 1994: Ergonomics
M Koller, M Härma, J T Laitinen, M Kundi, B Piegler, M Haider
There is strong evidence to suggest that circadian psychophysiological adaptation processes are modified by light, depending on its intensity and timing. To characterize such modifications and determine whether they are associated with an alteration in the day/night pattern of melatonin excretion, measurements were obtained around the clock in 14 permanent night workers, each studied over a 48 hr period in the field. The light exposure behavior of these workers was studied with a newly developed light dosimetry by measuring light intensity at eye level...
April 1994: Journal of Pineal Research
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