toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Bullough, J.D.; Rea, M.S.; Figueiro, M.G. url  doi
openurl 
  Title Of mice and women: light as a circadian stimulus in breast cancer research Type Journal Article
  Year 2006 Publication Cancer Causes & Control : CCC Abbreviated Journal Cancer Causes Control  
  Volume 17 Issue 4 Pages 375-383  
  Keywords Human Health; Animals; Breast Neoplasms/*physiopathology; *Circadian Rhythm; *Disease Models, Animal; Female; Humans; *Light; Light Signal Transduction; Mammary Neoplasms, Animal/*physiopathology; Melatonin/metabolism; Mice; Muridae/metabolism  
  Abstract OBJECTIVE: Nocturnal rodents are frequently used as models in human breast cancer research, but these species have very different visual and circadian systems and, therefore, very different responses to optical radiation or, informally, light. Because of the impact of light on the circadian system and because recent evidence suggests that cancer risk might be related to circadian disruption, it is becoming increasingly clear that optical radiation must be properly characterized for both nocturnal rodents and diurnal humans to make significant progress in unraveling links between circadian disruption and breast cancer. In this paper, we propose a quantitative framework for comparing radiometric and photometric quantities in human and rodent studies. METHODS: We reviewed published research on light as a circadian stimulus for humans and rodents. Both suppression of nocturnal melatonin and phase shifting were examined as outcome measures for the circadian system. RESULTS: The data were used to develop quantitative comparisons regarding the absolute and spectral sensitivity for the circadian systems of humans and nocturnal rodents. CONCLUSIONS: Two models of circadian phototransduction, for mouse and humans, have been published providing spectral sensitivities for these two species. Despite some methodological variations among the studies reviewed, the circadian systems of nocturnal rodents are approximately 10,000 times more sensitive to optical radiation than that of humans. Circadian effectiveness of different sources for both humans and nocturnal rodents are offered together with a scale relating their absolute sensitivities. Instruments calibrated in terms of conventional photometric units (e.g., lux) will not accurately characterize the circadian stimulus for either humans or rodents.  
  Address Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, Troy, NY 12180, USA. bulloj@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 0957-5243 ISBN Medium  
  Area (up) Expedition Conference  
  Notes PMID:16596289 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 726  
Permanent link to this record
 

 
Author Cajochen, C.; Jud, C.; Munch, M.; Kobialka, S.; Wirz-Justice, A.; Albrecht, U. url  doi
openurl 
  Title Evening exposure to blue light stimulates the expression of the clock gene PER2 in humans Type Journal Article
  Year 2006 Publication The European Journal of Neuroscience Abbreviated Journal Eur J Neurosci  
  Volume 23 Issue 4 Pages 1082-1086  
  Keywords Human Health; Adult; Color; Darkness; Dose-Response Relationship, Radiation; Female; Gene Expression/*radiation effects; Humans; *Light; Male; Melatonin/metabolism; Mucous Membrane/metabolism/radiation effects; Nuclear Proteins/genetics/*metabolism; Period Circadian Proteins; Transcription Factors/genetics/*metabolism  
  Abstract We developed a non-invasive method to measure and quantify human circadian PER2 gene expression in oral mucosa samples and show that this gene oscillates in a circadian (= about a day) fashion. We also have the first evidence that induction of human PER2 expression is stimulated by exposing subjects to 2 h of light in the evening. This increase in PER2 expression was statistically significant in comparison to a non-light control condition only after light at 460 nm (blue) but not after light exposure at 550 nm (green). Our results indicate that the non-image-forming visual system is involved in human circadian gene expression. The demonstration of a functional circadian machinery in human buccal samples and its response to light opens the door for investigation of human circadian rhythms at the gene level and their associated disorders.  
  Address Centre for Chronobiology, Psychiatric University Clinics, University of Basel, CH-4025 Basel, Switzerland. christian.cajochen@unibas.ch  
  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 0953-816X ISBN Medium  
  Area (up) Expedition Conference  
  Notes PMID:16519674 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 727  
Permanent link to this record
 

 
Author Czeisler, C.A.; Shanahan, T.L.; Klerman, E.B.; Martens, H.; Brotman, D.J.; Emens, J.S.; Klein, T.; Rizzo, J.F. 3rd url  doi
openurl 
  Title Suppression of melatonin secretion in some blind patients by exposure to bright light Type Journal Article
  Year 1995 Publication The New England Journal of Medicine Abbreviated Journal N Engl J Med  
  Volume 332 Issue 1 Pages 6-11  
  Keywords Human Health; Adolescent; Adult; Aged; Blindness/etiology/*physiopathology; Circadian Rhythm; Female; Humans; *Light; Male; Melatonin/blood/*secretion; Middle Aged; Photic Stimulation; Sleep Initiation and Maintenance Disorders/physiopathology; Visual Perception  
  Abstract BACKGROUND: Complete blindness generally results in the loss of synchronization of circadian rhythms to the 24-hour day and in recurrent insomnia. However, some blind patients maintain circadian entrainment. We undertook this study to determine whether some blind patients' eyes convey sufficient photic information to entrain the hypothalamic circadian pacemaker and suppress melatonin secretion, despite an apparently complete loss of visual function. METHODS: We evaluated the input of light to the circadian pacemaker by testing the ability of bright light to decrease plasma melatonin concentrations in 11 blind patients with no conscious perception of light and in 6 normal subjects. We also evaluated circadian entrainment over time in the blind patients. RESULTS: Plasma melatonin concentrations decreased during exposure to bright light in three sightless patients by an average (+/- SD) of 69 +/- 21 percent and in the normal subjects by an average of 66 +/- 15 percent. When two of these blind patients were tested with their eyes covered during exposure to light, plasma melatonin did not decrease. The three blind patients reported no difficulty sleeping and maintained apparent circadian entrainment to the 24-hour day. Plasma melatonin concentrations did not decrease during exposure to bright light in seven of the remaining blind patients; in the eighth, plasma melatonin was undetectable. These eight patients reported a history of insomnia, and in four the circadian temperature rhythm was not entrained to the 24-hour day. CONCLUSIONS: The visual subsystem that mediates light-induced suppression of melatonin secretion remains functionally intact in some sightless patients. The absence of photic input to the circadian system thus constitutes a distinct form of blindness, associated with periodic insomnia, that afflicts most but not all patients with no conscious perception of light.  
  Address Department of Medicine, Harvard Medical School, Boston, MA 02115  
  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 0028-4793 ISBN Medium  
  Area (up) Expedition Conference  
  Notes PMID:7990870 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 732  
Permanent link to this record
 

 
Author Foster, R.G.; Roenneberg, T. url  doi
openurl 
  Title Human responses to the geophysical daily, annual and lunar cycles Type Journal Article
  Year 2008 Publication Current Biology : CB Abbreviated Journal Curr Biol  
  Volume 18 Issue 17 Pages R784-R794  
  Keywords Human Health; Biological Clocks; Birth Rate; Circadian Rhythm; Death; Female; Human Activities; Humans; Male; Moon; *Periodicity; Photoperiod; Seasons; Sexual Behavior; Sleep  
  Abstract Collectively the daily, seasonal, lunar and tidal geophysical cycles regulate much of the temporal biology of life on Earth. The increasing isolation of human societies from these geophysical cycles, as a result of improved living conditions, high-quality nutrition and 24/7 working practices, have led many to believe that human biology functions independently of them. Yet recent studies have highlighted the dominant role that our circadian clock plays in the organisation of 24 hour patterns of behaviour and physiology. Preferred wake and sleep times are to a large extent driven by an endogenous temporal program that uses sunlight as an entraining cue. The alarm clock can drive human activity rhythms but has little direct effect on our endogenous 24 hour physiology. In many situations, our biology and our society appear to be in serious opposition, and the damaging consequences to our health under these circumstances are increasingly recognised. The seasons dominate the lives of non-equatorial species, and until recently, they also had a marked influence on much of human biology. Despite human isolation from seasonal changes in temperature, food and photoperiod in the industrialised nations, the seasons still appear to have a small, but significant, impact upon when individuals are born and many aspects of health. The seasonal changes that modulate our biology, and how these factors might interact with the social and metabolic status of the individual to drive seasonal effects, are still poorly understood. Lunar cycles had, and continue to have, an influence upon human culture, though despite a persistent belief that our mental health and other behaviours are modulated by the phase of the moon, there is no solid evidence that human biology is in any way regulated by the lunar cycle.  
  Address Circadian and Visual Neuroscience, Nuffield Laboratory of Ophthalmology, University of Oxford, Levels 5 & 6 West Wing, John Radcliffe Hospital, Headley Way, Oxford OX3 7BN, UK. russell.foster@eye.ox.ac.uk  
  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 0960-9822 ISBN Medium  
  Area (up) Expedition Conference  
  Notes PMID:18786384 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 752  
Permanent link to this record
 

 
Author Grundy, A.; Richardson, H.; Burstyn, I.; Lohrisch, C.; SenGupta, S.K.; Lai, A.S.; Lee, D.; Spinelli, J.J.; Aronson, K.J. url  doi
openurl 
  Title Increased risk of breast cancer associated with long-term shift work in Canada Type Journal Article
  Year 2013 Publication Occupational and Environmental Medicine Abbreviated Journal Occup Environ Med  
  Volume 70 Issue 12 Pages 831-838  
  Keywords Human Health; Adult; Aged; Aged, 80 and over; Breast Neoplasms/epidemiology/*etiology/metabolism; British Columbia/epidemiology; Case-Control Studies; Female; Humans; Menopause; Middle Aged; Occupational Diseases/*epidemiology; Ontario/epidemiology; Receptors, Estrogen/metabolism; Receptors, Progesterone/metabolism; Risk Factors; Tumor Markers, Biological/metabolism; Work Schedule Tolerance/*physiology; Young Adult  
  Abstract OBJECTIVES: Long-term night work has been suggested as a risk factor for breast cancer; however, additional studies with more comprehensive methods of exposure assessment to capture the diversity of shift patterns are needed. As well, few previous studies have considered the role of hormone receptor subtype. METHODS: Relationships between night shift work and breast cancer were examined among 1134 breast cancer cases and 1179 controls, frequency-matched by age in Vancouver, British Columbia, and Kingston, Ontario. Self-reported lifetime occupational histories were assessed for night shift work, and hormone receptor status obtained from tumour pathology records. RESULTS: With approximately one-third of cases and controls ever employed in night shift work, associations with duration demonstrated no relationship between either 0-14 or 15-29 years, while an association was apparent for >/=30 years (OR=2.21, 95% CI 1.14 to 4.31). This association with long-term night shift work is robust to alternative definitions of prolonged shift work, with similar results for both health and non-health care workers. CONCLUSIONS: Long-term night shift work in a diverse mix of occupations is associated with increased breast cancer risk and not limited to nurses, as in most previous studies.  
  Address Department of Public Health Sciences and Queen's Cancer Research Institute, Queen's University, Kingston, Ontario, Canada  
  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 1351-0711 ISBN Medium  
  Area (up) Expedition Conference  
  Notes PMID:23817841 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 757  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: