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Comparative Study 2007; 28(5): 575-579 PubMed PMID: 17984939 Citation  Keywords:  Adult, Aged, Circadian Rhythm:physiology, Humans, Male, Middle Aged, Nerve Growth Factors:blood, Oxygen:blood, Polysomnography, S100 Calcium Binding Protein beta Subunit, S100 Proteins:blood, Severity of Illness Index, Sleep Apnea, Obstructive:blood, Stat.   

OBJECTIVE: Responsible for sleep brain perfusion changes, obstructive sleep apnea (OSA) constitutes a cardiovascular risk. To find out about any diffuse damage to the brain tissue, we studied the S100B protein, whose serum level is known to rise in stroke and craniocerebral trauma.

METHODS: 60 men (mean age 51.7+/-11.8 years) referred to us for OSA without any major comorbidity were examined polygraphically. S100B was determined with electrochemiluminiscence immunoassay (ECLIA) from evening and morning blood samples.

RESULTS: All sixty men were diagnosed with OSA. The difference between the evening level of S100B 0.068+/-0.030 microg/l and the morning level 0.059+/-0.029 microg/l was significant (p=0.0004). Patients with mild OSA were found to have the evening S100B 0.063+/-0.023 microg/l, the morning level 0.042+/-0.012 microg/l, the difference being significant (p=0.00051). In moderate OSA the difference between the evening -0.070+/-0.017 microg/l and morning levels -0.055+/-0.025 microg/l was less significant (p=0.043). In severe OSA no difference was found between the evening and morning concentrations of S100B (0.070+/-0.036 microg/l and 0.070+/-0.031 microg/l respectively). The difference between the evening and morning S100B levels correlated negatively with AHI and ODI and positively with basal saturation and average minimal oxygen saturation.

CONCLUSIONS: Sleep with signs of severe OSA influences S100B protein release....

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Journal Article 2006; 27(1-2): 174-176 PubMed PMID: 16648807 Citation  Keywords:  Adolescent, Adult, Aged, Cataplexy:complications, Citalopram:therapeutic use, Ejaculation:drug effects, Female, Humans, Male, Middle Aged, Narcolepsy:complications, Retrospective Studies, Serotonin Uptake Inhibitors:therapeutic use, Sleep,.   

BACKGROUND: Narcolepsy with cataplexy is a debilitating sleep disease of which some symptoms can be treated with antidepressants. The antidepressant escitalopram is considered the most specific serotonin reuptake inhibitor.

PATIENTS AND METHODS: Ten patients (5 men and 5 women, age range 18-77 years) suffering from narcolepsy with cataplexy occurring at least weekly were treated with escitalopram 5 or 10 mg a day for 28-98 days. These patients were barred from taking any drugs influencing cataplexy and also had no other diseases affecting sleep or vigilance.

RESULTS: The mean number of cataplexies per week in 8 compliant patients declined significantly from 6.7 (+/-SD=7.2) to 0.3 (+/-0.6), P=0.02 (Sign test). Cataplexy completely disappeared in 6 patients. Subjective daytime sleepiness, power of concentration, quality of night sleep and mood remained unchanged. During the treatment, two patients had ejaculation disturbances. Two patients withdrew from the therapy (one because of ejaculation disturbance, the other for unknown reason).

CONCLUSION: Escitalopram proved to have anticataplectic effects in this small-scale open-label study....

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Clinical Trial 2005; 26(6): 657-661 PubMed PMID: 16380706 Citation  Keywords:  Bottle Feeding, Breast Feeding, Circadian Rhythm:physiology, Female, Humans, Infant, Infant, Newborn, Male, Melatonin:analogs & derivatives, Milk, Human:metabolism, Reference Values, Sleep:physiology, Statistics, Nonparametric, Tryptophan:metabolism,.   

INTRODUCTION: The hormone melatonin regulates the sleep and this pineal hormone is synthesized in the organism from the amino acid tryptophan. It is known that breast-fed babies have better sleep patterns and a better entrained sleep/wake cycle than bottle-fed babies (adapted formula).

OBJECTIVE: To compare the circadian rhythm of 6-sulfatoxymelatonin (aMT6s)--the metabolite of melatonin excreted in the urine--in urine of bottle-fed and breast-fed children, and relate it to the circadian rhythm of tryptophan in breast milk, also evaluating the possible effects on the baby's night-time rest.

METHODS: 16 infants of 12 weeks of age were studied, divided into two groups depending on their exclusively natural or artificial feeding. The circadian rhythm of 6-sulfatoxymelatonin in urine was measured for the two groups of infants and for the breast-feeding mothers. In the breast milk, the circadian rhythm of the amino acid tryptophan was measured. The rest of the infants was tested by wrist actimeters for a week and the sleep parameters of the infants were measured and evaluated.

RESULTS: The tryptophan in the breast milk presented a circadian rhythm with acrophase at around 03:00. This affected the 6-sulfatoxymelatonin circadian rhythm with acrophase at 06:00 in the breast-fed infants, and also promoted nocturnal sleep. Assumed sleep, actual sleep, and sleep efficiency were significantly increased in the breast fed infants with respect the formula fed infants.

CONCLUSION: A temporal relationship was observed between the circadian rhythm of 6-sulfatoxymelatonin of the exclusively breast-fed babies and that of tryptophan in the mother's milk. Acting this amino acid as a zeitgeber entrainment of the biological rhythms in the breast-fed infant....

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Journal Article 2005; 26(4): 289-292 PubMed PMID: 16135995 Citation  Keywords:  Animals, Appetite:physiology, Humans, Intracellular Signaling Peptides and Proteins:physiology, Narcolepsy:physiopathology, Neuropeptides:physiology, Neurosecretory Systems:physiology, Orexins, Sleep:physiology, Wakefulness:physiology,.   

: Orexins/hypocretins are recently discovered neuropeptides synthetized mainly by neurons located in the posterolateral hypothalamus. Hypocretin-1 and -2 are the same peptides as orexin-A and orexin-B. Orexin A is a 33 amino acid peptide with N-terminal pyroglutamyl residue and two intrachain disulphide bonds. Orexin B is a linear peptide of 28 amino acids. These two peptides are potent agonists at both the orexin-1 (OxR1) and orexin-2 (OxR2) receptors. Orexin-A is selective ligand for OxR1 and OX2 binds both orexins. The structure of orexins and their receptors is highly conservative in mammals. Orexin A sequence is identical in several mammalian species (human, mouse, rat, bovine and porcine). Intracerebroventricular administered orexin-A stimulates food intake and energy expenditure. Orexins are also involved in the regulation of neurohormones and pituitary hormones secretion as well as in the control of cardiovascular and sleep-wake function. Orexins also play a role in the pathogenesis of narcolepsy. Mutation in the gene coding preproorexin or OxR2 receptor gene results in narcolepsy in mice and canine. In patients with narcolepsy orexin neurotransmission was altered and orexin level in cerebrospinal fluid was undetectable....

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Clinical Trial 2003; 24(6): 463-467 PubMed PMID: 15073577 Citation  Keywords:  Adult, Continuous Positive Airway Pressure, Humans, Luteinizing Hormone:blood, Male, Middle Aged, Pituitary Gland:physiology, Sleep Apnea, Obstructive:physiopathology, Testis:physiology, Testosterone:blood, Treatment Outcome,.   

OBJECTIVES: Decreased libido and a decline in morning serum testosterone levels were reported in men with obstructive sleep apnea (OSA). Our study aimed to evaluate the pituitary-gonadal axis in middle age men with OSA before and after treatment with nasal continuous positive airway pressure (CPAP).

MATERIAL AND METHODS: Measurement of the nocturnal serum luteinizing hormone (LH) and testosterone levels and sleep recordings before and after nine months of CPAP treatment in five men with OSA aged 49.5+/-5.2 years. Patients were evaluated during nocturnal sleep at base line and during CPAP treatment. Serum LH and testosterone levels were determined at 20 minutes interval between 1900h and 0700h with concomitant determination of sleep quality, respiration and oxygen saturation.

RESULTS: At base line, patients had higher RDI and PaO2<90%, lower mean and integrated (AUC) values of LH and testosterone. During CPAP treatment, RDI and PaO2<90% were normal. Mean and AUC values of testosterone and LH increased.

CONCLUSIONS: OSA in men is associated with dysfunction of the pituitary-gonadal axis. The central suppression of nocturnal testosterone in these patients is partially corrected during chronic CPAP treatment....

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Journal Article 2003; 24(3-4): 151-160 PubMed PMID: 14523349 Citation  Keywords:  Aging:physiology, Attention:physiology, Brain:growth & development, Consciousness Disorders:psychology, Electroencephalography, Electrophysiology, Eye Movements:physiology, Female, Gravitation, Humans, Learning:physiology, Male, Sleep:physiology,.   

: The interest in studying the brain electrical activity as a function of the development of intelligence has been spurred by the need to understand how the brain responds to environmental information. The description of sleep in mentally retarded children reveals deviant patterns of the EEG-spindles and of the eye movement activity (REM sleep) when compared to normal children. The patterns may be considered as a valuable index of mental function. According to experimental evidence, the distribution of the eye movements of sleep appears either as random or ordered. The latter are altered in the mentally handicapped in whom the appearance out of chaos, of the order which is needed for intelligence and memory to function, is altered. The sleep signs are redundant as from birth. Their pattern is also related to the psychomotor development of the infant. If their distribution remains random, or appears in long uninterrupted sequences of waves as in epilepsy, intelligence does not develop. A similar strategy appears to function in the foetus when nature organizes the structures that will lead to the development of intelligence. The eye movement patterns of sleep change in the pregnant women as a function of term and resemble those of premature babies of a similar gestational age. They also change as a function of the menstrual cycle and more generally as a function of age. The hypothesis that attention is the diurnal equivalent of REM sleep is discussed. Attempts at modelling the eye movement patterns of REM sleep as a function of near zero gravity environments have been made. 1) By means of a Montecarlo simulation using the semi Markov model during the Spacelab 1 flight. 2) With the method of the single and multiple g-phase transition analysis of the strange attractor dimension (d) during parabolic flights. The implication of the latter for the neural processes involved in learning is that the central nervous system can preserve intact, from input to output, over a period of several days, all the information it receives 3) The relation between spindles and eye movements has also been viewed by a quantum approach which is another medium between the information and the way of describing it....

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Comment 2002; 23(5-6): 385-386 PubMed PMID: 12500157 Citation  Keywords:  Child, Preschool, Circadian Rhythm:physiology, Humans, Japan, Melatonin:analogs & derivatives, Photic Stimulation, Photoperiod, Saliva:chemistry, Sleep:physiology, Time Factors, Urine:chemistry,.   

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Clinical Trial 2002; 23(3): 213-217 PubMed PMID: 12080281 Citation  Keywords:  Adult, Body Temperature:drug effects, Circadian Rhythm:drug effects, Humans, Male, Melatonin:blood, Pineal Gland:drug effects, Pyridoxine:administration & dosage, Sleep:drug effects,.   

OBJECTIVES: To determine pineal response to pyridoxine in normal men.

MATERIAL AND METHODS: Twelve healthy men were given orally pyridoxine (100 mg) or placebo at 1700h. Serum melatonin levels were determined every 30 minutes with simultaneous measurement of core body temperature between 1700h to 0300h. Polysomnographic sleep recordings were performed between 1800h to 2000h.

RESULTS: Serum melatonin levels after both placebo and pyridoxine showed a nocturnal rise occurring at 22:10+/-1:22h and 22:24+/-1:09h, respectively. The melatonin onset, peak, mean and area under the curve (AUC) values after pyridoxine (3.2+/-1.6 pg/ml, 47.2+/-22.6 pg/ml, 31.5+/-11.0 pg/ml and 173.5+/-138.4 pg/ml x min, respectively) were similar to the values after placebo administration (4.7+/-1.6 pg/ml, 53.9+/-26.0 pg/ml, 37.2+/-2.8 pg/ml and 205.3+/-137.8 pg/ml x min, respectively). CBT revealed a significant nocturnal decline but without significant difference between pyridoxine and placebo. Sleep amount and architecture were similar after the two treatments.

CONCLUSIONS: In adult man, the oral administration of 100 mg-pyridoxine during the evening hours has no effect on melatonin secretion nor does it alter CBT or sleep quality....

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