|   | 
Details
   web
Records
Author Ruger, M.; Gordijn, M.C.M.; Beersma, D.G.M.; de Vries, B.; Daan, S.
Title Time-of-day-dependent effects of bright light exposure on human psychophysiology: comparison of daytime and nighttime exposure Type Journal Article
Year 2006 Publication American Journal of Physiology. Regulatory, Integrative and Comparative Physiology Abbreviated Journal Am J Physiol Regul Integr Comp Physiol
Volume 290 Issue 5 Pages R1413-20
Keywords (down) Human Health; Adult; Body Temperature/*physiology; Circadian Rhythm/*physiology; Fatigue/*physiopathology; Heart Rate/*physiology; Humans; Hydrocortisone/*blood; *Light; Sleep Stages/*physiology
Abstract Bright light can influence human psychophysiology instantaneously by inducing endocrine (suppression of melatonin, increasing cortisol levels), other physiological changes (enhancement of core body temperature), and psychological changes (reduction of sleepiness, increase of alertness). Its broad range of action is reflected in the wide field of applications, ranging from optimizing a work environment to treating depressed patients. For optimally applying bright light and understanding its mechanism, it is crucial to know whether its effects depend on the time of day. In this paper, we report the effects of bright light given at two different times of day on psychological and physiological parameters. Twenty-four subjects participated in two experiments (n = 12 each). All subjects were nonsmoking, healthy young males (18-30 yr). In both experiments, subjects were exposed to either bright light (5,000 lux) or dim light <10 lux (control condition) either between 12:00 P.M. and 4:00 P.M. (experiment A) or between midnight and 4:00 A.M. (experiment B). Hourly measurements included salivary cortisol concentrations, electrocardiogram, sleepiness (Karolinska Sleepiness Scale), fatigue, and energy ratings (Visual Analog Scale). Core body temperature was measured continuously throughout the experiments. Bright light had a time-dependent effect on heart rate and core body temperature; i.e., bright light exposure at night, but not in daytime, increased heart rate and enhanced core body temperature. It had no significant effect at all on cortisol. The effect of bright light on the psychological variables was time independent, since nighttime and daytime bright light reduced sleepiness and fatigue significantly and similarly.
Address Department of Chronobiology, University of Groningen, The Netherlands. Melanie.Rueger@med.nyu.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0363-6119 ISBN Medium
Area Expedition Conference
Notes PMID:16373441 Approved no
Call Number LoNNe @ kagoburian @ Serial 801
Permanent link to this record
 

 
Author Haus, E.; Smolensky, M.
Title Biological clocks and shift work: circadian dysregulation and potential long-term effects Type Journal Article
Year 2006 Publication Cancer Causes & Control : CCC Abbreviated Journal Cancer Causes Control
Volume 17 Issue 4 Pages 489-500
Keywords (down) Human Health; Adaptation, Physiological; Animals; Biological Clocks; Cardiovascular Abnormalities/etiology; Chronobiology Disorders/*complications/physiopathology; Chronobiology Phenomena; Humans; Neoplasms/etiology; Occupational Diseases/*etiology; Risk Factors; Suprachiasmatic Nucleus/physiopathology; *Work Schedule Tolerance
Abstract Long-term epidemiologic studies on large numbers of night and rotating shift workers have suggested an increase in the incidence of breast and colon cancer in these populations. These studies suffer from poor definition and quantification of the work schedules of the exposed subjects. Against this background, the pathophysiology of phase shift and phase adaptation is reviewed. A phase shift as experienced in night and rotating shift work involves desynchronization at the molecular level in the circadian oscillators in the central nervous tissue and in most peripheral tissues of the body. There is a change in the coordination between oscillators with transient loss of control by the master-oscillator (the Suprachiasmatic Nucleus, SCN) in the hypothalamus. The implications of the pathophysiology of phase shift are discussed for long-term health effects and for the design of ergonomic work schedules minimizing the adverse health effects upon the worker.
Address Department of Laboratory Medicine & Pathology, University of Minnesota, Health Partners Medical Group, Regions Hospital, St. Paul, Minnesota 55101, USA. Erhard.X.Haus@Healthpartners.com
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-5243 ISBN Medium
Area Expedition Conference
Notes PMID:16596302 Approved no
Call Number LoNNe @ kagoburian @ Serial 760
Permanent link to this record
 

 
Author Anisimov, V. N.
Title Light pollution, reproductive function and cancer risk Type Journal Article
Year 2006 Publication Neuroendocrinology Letters Abbreviated Journal
Volume 27 Issue 1-2 Pages 35-52
Keywords (down) Human Health
Abstract At present, light pollution (exposure to light-at-night) both in the form of occupational exposure during night work and as a personal choice and life style, is experienced by numerous night-active members of our society. Disruption of the circadian rhythms induced by light pollution has been associated with cancer in humans. There are epidemiological evidences of increased breast and colon cancer risk in shift workers. An inhibition of the pineal gland function with exposure to the constant light (LL) regimen promoted carcinogenesis whereas the light deprivation inhibits the carcinogenesis. Treatment with pineal indole hormone melatonin inhibits carcinogenesis in pinealectomized rats or animals kept at the standard light/dark regimen (LD) or at the LL regimen. These observations might lead to use melatonin for cancer prevention in groups of humans at risk of light pollution.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ kagoburian @ Serial 703
Permanent link to this record
 

 
Author Curtis, A.M.; FitzGerald, G.A.
Title Central and peripheral clocks in cardiovascular and metabolic function Type Journal Article
Year 2006 Publication Annals of Medicine Abbreviated Journal Ann Med
Volume 38 Issue 8 Pages 552-559
Keywords (down) Human Health
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0785-3890 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ kagoburian @ Serial 730
Permanent link to this record
 

 
Author Figueiro, M.G.; Rea, M.S.; Bullough, J.D.
Title Does architectural lighting contribute to breast cancer? Type Journal Article
Year 2006 Publication Journal of Carcinogenesis Abbreviated Journal J Carcinog
Volume 5 Issue Pages 20
Keywords (down) Human Health
Abstract OBJECTIVES: There is a growing interest in the role that light plays on nocturnal melatonin production and, perhaps thereby, the incidence of breast cancer in modern societies. The direct causal relationships in this logical chain have not, however, been fully established and the weakest link is an inability to quantitatively specify architectural lighting as a stimulus for the circadian system. The purpose of the present paper is to draw attention to this weakness. DATA SOURCES AND EXTRACTION: We reviewed the literature on the relationship between melatonin, light at night, and cancer risk in humans and tumor growth in animals. More specifically, we focused on the impact of light on nocturnal melatonin suppression in humans and on the applicability of these data to women in real-life situations. Photometric measurement data from the lighted environment of women at work and at home is also reported. DATA SYNTHESIS: The literature review and measurement data demonstrate that more quantitative knowledge is needed about circadian light exposures actually experienced by women and girls in modern societies. CONCLUSION: Without such quantitative knowledge, limited insights can be gained about the causal relationship between melatonin and the etiology of breast cancer from epidemiological studies and from parametric studies using animal models.
Address Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street Troy, NY 12180 USA. figuem@rpi.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-3163 ISBN Medium
Area Expedition Conference
Notes PMID:16901343; PMCID:PMC1557490 Approved no
Call Number LoNNe @ kagoburian @ Serial 746
Permanent link to this record