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Journal Article 2002; 23(Suppl 4): 67-77 PubMed PMID: 12496737 Citation  Keywords:  Animals, Cognition:drug effects, Embryonic Development:drug effects, Gonadal Steroid Hormones:pharmacology, Humans, Models, Biological, Periodicity, Seasons, Sex Characteristics,.   

: The major sex differences in cognitive skills are summarized, and the role of sex hormones in early organization and possible maintenance of these differences is discussed. Using animal models and human hormonal anomalies, a good case can be made that prenatal androgens strongly influence adult cognitive pattern, though the relation between baseline androgens and spatial ability, for example, need not be linear. Moreover, men and women remain sensitive to variation in hormonal state, as evidenced in the fluctuations in cognitive and motor performance across natural diurnal, menstrual and circannual rhythms. Evidence from administration of exogenous hormones in humans is more equivocal, though this field ultimately should yield useful information....

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Journal Article 2002; 23(Suppl 2): 23-27 PubMed PMID: 12163844 Citation  Keywords:  Animals, Biological Clocks:physiology, Humans, Light, Melatonin:physiology, Pineal Gland:physiology, Seasons,.   

: In mammals including man, the most important zeitgeber for endogenous rhythms is the environmental light/dark cycle. Mammals perceive light through the eyes and that perception is relayed to the suprachiasmatic nucleus (SCN) by means of neuronal signals. The SCN, in turn, innervates the pineal gland, resulting in the production and release of melatonin almost exclusively during night-time hours. Thus, besides object recognition, eyes serve as the sensory organ for detecting the presence or absence of light. The way that light entrains the SCN is still a matter of intense research. It has been shown, for example, that the light intensities required for affecting melatonin rhythms are much higher than the intensities needed for object identification. On the other hand, even in rodents who completely lack the "classical" photoreceptors of the retina, their endogenous rhythms still can be synchronized by normal light/dark cycles. These two observations led to the hypothesis that there must be photoreceptors, apart from the known (object-identifying) retinal photoreceptors, which are responsible for the entrainment of internal rhythms. Very recently, a number of reports showed that in fact a completely new type of retinal photoreceptor, located in ganglion cells, may be responsible for entraining the SCN. It contains a photopigment, melanopsin, which shares homologies with rhodopsin, but also is evolutionarily older. Compared to rods or cones, the melanopsin-containing neurons are rare, but evenly distributed within the retina, indicating that they serve as a global, integrating light sensor. These ganglion cells apparently project directly into the SCN. Taken together, these new developments in photo-chronobiology open new areas of research. It will be of special interest, for example, to determine how the photosensitive ganglion cells and their dendrites integrate the environmental light stimuli....

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Comparative Study 2002; 23(Suppl 1): 61-66 PubMed PMID: 12019354 Citation  Keywords:  Animals, Antioxidants:pharmacology, Humans, Immunity:drug effects, Melatonin:pharmacology, Pineal Gland:physiology, Receptors, Cell Surface:physiology, Receptors, Cytoplasmic and Nuclear:physiology, Receptors, Melatonin, Seasons,.   

: Pineal gland, by the diurnal rhythm of synthesis and release of its principal hormone, melatonin (MEL), is involved in reciprocal relationships between neuroendocrine and immune systems, responsible for keeping internal homeostasis in vertebrate animals. In this paper the experimental data, indicating that both strategic (developmental, thus antigen independent) and emergency (evoked by antigenic activation of the mature immune system) levels of interactions between pineal gland and immune system, operate in mammals and birds, are reviewed. The cells and organs of immune system using membrane receptors as well as nuclear orphan receptors perceive MEL message. Effects exerted by MEL on immune parameters are different, and depend on several factors, including dose and way of MEL application, species, sex, age of animal, its immune system maturation, way of immune system activation, and parameter examined, as well as the season, circadian rhythm of both immunity and pineal gland function, stressful conditions, accompanying experimental procedure, etc. In turn, lymphoid organ-derived hormones and cytokines, soluble factors secreted by activated immune cells act as messages understood by the pineal gland, closing the regulatory loop of the bi-directional functional connections between both systems....

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Clinical Trial 2002; 23(2): 109-113 PubMed PMID: 12011795 Citation  Keywords:  Adult, Antidepressive Agents, Tricyclic:administration & dosage, Depressive Disorder, Major:drug therapy, Double-Blind Method, Female, Humans, Imipramine:administration & dosage, Inpatients, Male, Middle Aged, Phototherapy, Recurrence, Seasons, Treatment .   

INTRODUCTION: The aim of a double-blind study was to assess the efficacy of bright light therapy and/or imipramine in the treatment of inpatients suffering with recurrent non-seasonal major depressive disorder.

METHOD: 34 in-patients with DSM-III-R diagnosis of major depressive disorder, recurrent type, were randomly allocated into 3 treatment groups. After 4-day washout period with baseline assessment they underwent 3 weeks of different types of treatment: a) Group A: bright light therapy (5000 lux from 6-8 a.m.) and imipramine 150 mg/day. b) Group B: bright light therapy (5000 lux from 6-8 a.m.) and imipramine-like placebo. c) Group C: dim red light (500 lux from 6-8 a.m.) and imipramine 150 mg/day. Outcome measures included weekly Hamilton Psychiatric Rating Scale for Depression, Clinical Global Impression Scale, Montgomery and Asberg Psychiatric Rating Scale for Depression and Beck Depression Inventory.

RESULTS: Patients of all three groups improved significantly. The improvement of the patients of group B treated with bright light therapy plus placebo was superior to the other two groups, but not significantly.

CONCLUSION: Bright light therapy can be effective in the treatment of non-seasonal major depressive disorder....

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