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Daniela Leite de Oliveira, Camila Hirotsu, Sergio Tufik and Monica Levy Andersen

, researchers have suggested the participation of vitamin D in regulatory mechanisms of sleep–wake cycle, based on the evidence suggesting that the reduction of this vitamin is also associated with sleep disorders ( McCarty et al . 2012 , Mete et al . 2013

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Sophie M T Wehrens, Shelagh M Hampton, Rebecca E Finn and Debra J Skene

endogenous processes are synchronised to or in phase with daily routines, such as food intake and sleep. However, shift work studies done by our group ( Hampton et al . 1996 , Ribeiro et al . 1998 , Lund et al . 2001 ) and by other groups ( Simon et al

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A Barkan

Acromegaly is associated with increased cardiovascular morbidity and mortality. However, increased growth hormone (GH) and insulin-like growth factor (IGF)-I exert deleterious effects on multiple organs and tissues and, in a direct or an indirect fashion, effect non-cardiac complications as well. The current knowledge about acromegalic arthropathy and sleep apnea will be briefly summarized here.


The articular manifestations of acromegaly were first recognized in Pierre Marie's original description of this disease in 1886. It is, perhaps, symbolic that Marie's name is connected not only with acromegaly but also with Marie-Strumpell disease (ankylosing spondylitis).

Arthropathy affects many, if not most, patients with acromegaly. In one form or another, musculoskeletal complaints are a leading cause of morbidity and functional disability in acromegaly. Several studies provided detailed epidemiologic description of acromegalic arthropathy. In the largest series of that kind, Detenbeck et al. (1973) found that 62% of the 229 patients examined had at

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Muneki Ikeda, Yasushi Hojo, Yoshimasa Komatsuzaki, Masahiro Okamoto, Asami Kato, Taishi Takeda and Suguru Kawato

using microdialysis. Our previous study showed that in the cerebrospinal fluid (CSF), the CORT concentration is ∼30 nM in the awake state and ∼3 nM in the sleep state ( Higo et al . 2011 ). These concentrations are much lower than the stress level of

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David E Henley, Fiona Buchanan, Rosemary Gibson, Jennie A Douthwaite, Susan A Wood, Wolfram W Woltersdorf, James R Catterall and Stafford L Lightman

Introduction Obstructive sleep apnea (OSA) is a common condition, with an estimated prevalence of 3–7% for adult men and 2–5% for adult women in the general population ( Punjabi 2008 ). It is associated with intermittent upper airway obstruction and

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The effects of strenuous daytime physical exercise were examined in 12 healthy male volunteers. All-night electrophysiological recordings were made and blood was sampled during sleep by indwelling venous catheter.

Plasma growth hormone levels were significantly increased after exercise but the sleep electroencephalographic patterns of nights after exercise did not differ significantly from those of control nights. Plasma corticosteroids were decreased after exercise. It is suggested that higher levels of growth hormone are consistent with reparative processes during sleep.

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L Morgan, J Arendt, D Owens, S Folkard, S Hampton, S Deacon, J English, D Ribeiro and K Taylor

This study was undertaken to determine whether the internal clock contributes to the hormone and metabolic responses following food, in an experiment designed to dissociate internal clock effects from other factors. Nine female subjects participated. They lived indoors for 31 days with normal time cues, including the natural light: darkness cycle. For 7 days they retired to bed from 0000 h to 0800 h. They then underwent a 26-h 'constant routine' (CR) starting at 0800 h, being seated awake in dim light with hourly 88 Kcal drinks. They then lived on an imposed 27-h day (18 h of wakefulness, 9 h allowed for sleep), for a total of 27 days. A second 26-h CR, starting at 2200 h, was completed. During each CR salivary melatonin and plasma glucose, triacylglycerol (TAG), non-essential fatty acids (NEFA), insulin, gastric inhibitory peptide (GIP) and glucagon-like peptide-1 (GLP-1) were measured hourly. Melatonin and body temperature data indicated no shift in the endogenous clock during the 27-h imposed schedule. Postprandial NEFA, GIP and GLP-1 showed no consistent effects. Glucose, TAG and insulin increased during the night in the first CR. There was a significant effect of both the endogenous clock and sleep for glucose and TAG, but not for insulin. These findings may be relevant to the known increased risk of cardiovascular disease amongst shift workers.

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Recording electrodes were implanted in contact with the dura mater overlying the parietal cortex of six female goats, four of which were lactating. After recovery from surgery and complete familiarization with the housing conditions, the personnel and the recording technique, each goat was observed continuously for 24 h with simultaneous recording of the cortical electroencephalogram (EEG). Remote blood sampling was carried out every 30 min without disturbing the animal. Apart from the release of growth hormone (GH) associated with morning milking in two of the goats, there was no consistent relationship between the apparently spontaneous, episodic release of GH and behaviour, stages of sleep, cortical EEG, air temperature, time of day or night, obvious environmental stimuli which arose from the normal husbandry routine, or the levels of prolactin, insulin, glucose or free fatty acids in the blood. There was also no relationship between the release of prolactin and the stages of sleep.

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Kanta Kon, Hiroshi Tsuneki, Hisakatsu Ito, Yoshinori Takemura, Kiyofumi Sato, Mitsuaki Yamazaki, Yoko Ishii, Masakiyo Sasahara, Assaf Rudich, Takahiro Maeda, Tsutomu Wada and Toshiyasu Sasaoka

of partial sleep deprivation is enough to cause insulin resistance in healthy humans ( Donga et al. 2010 ). Unbalanced regulations of the hormonal and autonomic nervous systems contribute to the disrupted sleep-induced impairment of glucose

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Shannon M Bailey, Uduak S Udoh and Martin E Young

Introduction Both energetic supply and demand fluctuate as a function of time-of-day, concomitant with daily sleep–wake and fasting–feeding cycles. It is therefore not surprising that marked diurnal variations in metabolism are observed at multiple