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Author Bedrosian, T.A. (ed) pdf  url
openurl 
  Title Circadian Disruption by Light at Night: Implications for Mood Type Book Whole
  Year 2013 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords circadian disruption; sleep; light at night; melanopsin; mood; mental health; Mood Disorders; epigenetics; red light  
  Abstract Life on Earth has adapted to a consistent 24-h solar cycle. Circadian rhythms in physiology and behavior remain synchronized to the environment using light as the most potent entraining cue. During the past century, however, the widespread adoption of electric light has led to `round-the-clock’ societies. Instead of aligning with the environment, individuals follow artificial and often erratic light cycles created by social and work schedules. In particular, exposure to artificial light at night (LAN), termed “light pollution”, has become pervasive over the past 100 years. Virtually every individual living in the U.S. and Europe experiences this aberrant light exposure, and moreover about 20% of the population performs shift work. LAN may disrupt physiological timekeeping, leading to dysregulation of internal processes and misalignment between behavior and the environment. Recent evidence suggests that individuals exposed to excessive LAN, such as night shift workers, have increased risk for depressive disorders, but the biological mechanism remains unspecified. In mammals, intrinsically photosensitive retinal ganglion cells (ipRGCs) project light information to (1) the suprachiasmatic nucleus (SCN) in the hypothalamus, regulating circadian rhythms, and (2) to limbic regions, putatively regulating mood. Thus, LAN has the potential to affect both circadian timekeeping and mood. In this dissertation, I present evidence from rodent studies supporting the novel hypothesis that night-time exposure to light disrupts circadian organization and contributes to depressed mood. First, I consider the physiological and behavioral consequences associated with unnatural exposure to LAN. The effects of LAN on circadian output are considered in terms of locomotor activity, the diurnal cortisol rhythm, and diurnal clock protein expression in the brain in Chapter 2. The influence of LAN on behavior and brain plasticity is discussed, with particular focus on depressive-like behavior (Chapter 3) and effects of SSRI treatment (Chapter 4). Effects of LAN on structural plasticity and gene expression in the brain are described, with emphasis on potential correlates of the depressive-like behavior observed under LAN in Chapter 5. Given the prevalence of LAN exposure and its importance, strategies for reversing the effects are offered. Specifically, eliminating LAN quickly reverses behavioral and physiological effects of exposure as described in Chapter 5. In Chapter 6 I report that administration of a pharmacological cytokine inhibitor prevents depressive-like behaviors in LAN, implicating brain inflammation in the behavioral effect. Finally, I demonstrate in Chapter 7 that exposure to red wavelength LAN reduces the effects on brain and behavior, suggesting that LAN acts through specific retinal pathways involving melanopsin. Taken together, these studies demonstrate the consequences of LAN, but also outline potential avenues for prevention or intervention.  
  Address Department of Neuroscience and The Institute for Behavioral Medicine Research The Ohio State University  
  Corporate Author Thesis Ph.D. thesis  
  Publisher (up) Place of Publication Editor Bedrosian, T.A.  
  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 IDA @ john @ Serial 323  
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Author Vetter, C.; Juda, M.; Lang, D.; Wojtysiak, A.; Roenneberg, T. url  openurl
  Title Blue-enriched office light competes with natural light as a zeitgeber Type Journal Article
  Year 2011 Publication Scandinavian Journal of Work, Environment & Health Abbreviated Journal Scand J Work Environ Health  
  Volume 37 Issue 5 Pages 437-445  
  Keywords *Circadian Rhythm; *Color; Humans; *Lighting; *Occupational Health; Sleep; Wakefulness; blue light; circadian disruption; Circadian rhythm; sleep  
  Abstract OBJECTIVES: Circadian regulation of human physiology and behavior (eg, body temperature or sleep-timing), depends on the “zeitgeber” light that synchronizes them to the 24-hour day. This study investigated the effect of changing light temperature at the workplace from 4000 Kelvin (K) to 8000 K on sleep-wake and activity-rest behavior. METHODS: An experimental group (N=27) that experienced the light change was compared with a non-intervention group (N=27) that remained in the 4000 K environment throughout the 5-week study period (14 January to 17 February). Sleep logs and actimetry continuously assessed sleep-wake behavior and activity patterns. RESULTS: Over the study period, the timing of sleep and activity on free days steadily advanced parallel to the seasonal progression of sunrise in the non-intervention group. In contrast, the temporal pattern of sleep and activity in the experimental group remained associated with the constant onset of work. CONCLUSION: The results suggest that artificial blue-enriched light competes with natural light as a zeitgeber. While subjects working under the warmer light (4000 K) appear to entrain (or synchronize) to natural dawn, the subjects who were exposed to blue-enriched (8000 K) light appear to entrain to office hours. The results confirm that light is the dominant zeitgeber for the human clock and that its efficacy depends on spectral composition. The results also indicate that blue-enriched artificial light is a potent zeitgeber that has to be used with diligence.  
  Address Institute for Medical Psychology, Centre of Chronobiology, Ludwig-Maximilians-Universitat, Munich, Germany  
  Corporate Author Thesis  
  Publisher (up) Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0355-3140 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21246176 Approved no  
  Call Number IDA @ john @ Serial 350  
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Author Dauchy, R.T.; Xiang, S.; Mao, L.; Brimer, S.; Wren, M.A.; Yuan, L.; Anbalagan, M.; Hauch, A.; Frasch, T.; Rowan, B.G.; Blask, D.E.; Hill, S.M. url  doi
openurl 
  Title Circadian and melatonin disruption by exposure to light at night drives intrinsic resistance to tamoxifen therapy in breast cancer Type Journal Article
  Year 2014 Publication Cancer Research Abbreviated Journal Cancer Res  
  Volume 74 Issue 15 Pages 4099-4110  
  Keywords *Cancer; breast cancer; melatonin; endocrinology; tamoxifen; *Circadian Rhythm; circadian disruption; human health; epidemiology  
  Abstract Resistance to endocrine therapy is a major impediment to successful treatment of breast cancer. Preclinical and clinical evidence links resistance to antiestrogen drugs in breast cancer cells with the overexpression and/or activation of various pro-oncogenic tyrosine kinases. Disruption of circadian rhythms by night shift work or disturbed sleep-wake cycles may lead to an increased risk of breast cancer and other diseases. Moreover, light exposure at night (LEN) suppresses the nocturnal production of melatonin that inhibits breast cancer growth. In this study, we used a rat model of estrogen receptor (ERalpha(+)) MCF-7 tumor xenografts to demonstrate how altering light/dark cycles with dim LEN (dLEN) speed the development of breast tumors, increasing their metabolism and growth and conferring an intrinsic resistance to tamoxifen therapy. These characteristics were not observed in animals in which the circadian melatonin rhythm was not disrupted, or in animals subjected to dLEN if they received nocturnal melatonin replacement. Strikingly, our results also showed that melatonin acted both as a tumor metabolic inhibitor and a circadian-regulated kinase inhibitor to reestablish the sensitivity of breast tumors to tamoxifen and tumor regression. Together, our findings show how dLEN-mediated disturbances in nocturnal melatonin production can render tumors insensitive to tamoxifen. Cancer Res; 74(15); 4099-110. (c)2014 AACR.  
  Address Departments of Structural and Cellular Biology and Tulane Cancer Center and Louisiana Cancer Research Consortium; Tulane Circadian Cancer Biology Group; and  
  Corporate Author Thesis  
  Publisher (up) Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-5472 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:25062775; PMCID:PMC4119539 Approved no  
  Call Number IDA @ john @ Serial 355  
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Author Gaston, K.J. url  doi
openurl 
  Title Sustainability: A green light for efficiency Type Journal Article
  Year 2013 Publication Nature Abbreviated Journal Nature  
  Volume 497 Issue 7451 Pages 560-561  
  Keywords Editorial; Animals; Atmosphere/chemistry; Carbon Dioxide/analysis; Circadian Rhythm/physiology; Conservation of Energy Resources/economics/*methods/*trends; Global Warming/prevention & control; Humans; Lighting/*economics/instrumentation/statistics & numerical data/*trends; Public Health  
  Abstract  
  Address Environment and Sustainability Institute, University of Exeter, Penryn, UK. k.j.gaston@exeter.ac.uk  
  Corporate Author Thesis  
  Publisher (up) Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23719447 Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 459  
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Author Figueiro, M.G.; Wood, B.; Plitnick, B.; Rea, M.S. url  doi
openurl 
  Title The impact of watching television on evening melatonin levels: Impact of watching television on evening melatonin Type Journal Article
  Year 2013 Publication Journal of the Society for Information Display Abbreviated Journal Jnl Soc Info Display  
  Volume 21 Issue 10 Pages 417-421  
  Keywords Human Health; television; correlated color temperature; sleep; melatonin levels; blue light; circadian disruption  
  Abstract Self-luminous electronic devices emit optical radiation at short wavelengths, close to the peak sensitivity of melatonin suppression. The present paper investigated if light from a 178-cm (70 in.) television suppressed melatonin. Results showed that light from televisions does not impact melatonin levels in the evening.  
  Address  
  Corporate Author Thesis  
  Publisher (up) Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1071-0922 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 498  
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