J Arendt

..Anecdotal evidence for the use of melatonin needs to be replaced by data from well-controlled, preferably multi-centre, randomised clinical trials...

..It is also the marker rhythm of choice for the determination of circadian phase and period. This review outlines the current state of knowledge within a physiological perspective with emphasis on human biological rhythms...

..Its effects on sleep in free run are complex, depend on circadian time of administration, and can in part be interpreted on a photoperiodic basis...

..Thus, ocular light appears to be the predominant time cue and major determinant of circadian rhythm type. Optimisation of the light for entrainment (intensity, duration, wavelength, time of administration) requires further study...

..6 +/- 0.4 and 0.5 +/- 0.3 microgram/h, respectively). These results indicate that a higher proportion of NPL subjects have abnormal melatonin rhythms compared to those with LP...

..The results suggest that prior knowledge of the subject's type of circadian rhythm, and timing of treatment in relation to the individual's circadian phase, may improve the efficacy of melatonin...

..Compared with placebo, melatonin advanced the sleep period in subjects with DSPS. Melatonin also improved a number of sleep parameters in blind subjects suffering from non-24-hour sleep wake disorder...

..In particular, the methods agreed when assessing changes in sleep in relation to a circadian phase marker (the 6-sulphatoxymelatonin (aMT6s) rhythm) in both entrained (n = 30) and free-running (n = 4) subjects...

..The aim of the study was to assess sleep with simultaneous measurement of an endogenous marker of the circadian clock, namely 6-sulphatoxymelatonin (aMT6s)...

..Taken together these findings suggest that melatonin is of benefit in facilitating adaptation to forced phase shifts and in conditions of circadian rhythm disturbance...

..74). 5. Our data strongly support a primary role for a novel short-wavelength photopigment in light-induced melatonin suppression and provide the first direct evidence of a non-rod, non-cone photoreceptive system in humans...

..We conclude that acute exposure to 50 Hz MFs does not have a significant effect on the normal nighttime production of melatonin in young men...

..These results suggest that if the circadian system is acutely responsive to MF exposure of this nature, an intact circadian axis may be necessary in order to observe an effect on the production on melatonin from the pineal gland..

..009). This study demonstrates the existence of gender and time-of-day differences in TAG responses to a meal. These raised TAG levels at night, for a prolonged time in men, may be relevant to the increased risk of CHD in shift workers...

..05, P less than 0.01), 0130 h (P less than 0.01, P less than 0.01) and 0200 h (P less than 0.01, P less than 0.001) respectively.(ABSTRACT TRUNCATED AT 250 WORDS)..

..83 h) of the day shift week. As a group, the subjects adapted to the night shift but very large individual variations were seen during the day shift. These individual differences clearly require further study...

..Industrial accidents associated with night work are common, perhaps the most famous being Chernobyl, Three Mile Island, and Bhopal...

..Recommendations on protocol design are also made which, if followed, should enable researchers to eliminate or control for many of the confounding factors associated with melatonin being an output from the circadian clock...

..Although the bright green light helped counteract sleepiness, any causal link with changes in melatonin output seem tenuous...