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Author van Diepen, H.C.; Foster, R.G.; Meijer, J.H. url  doi
openurl 
  Title A colourful clock Type Journal Article
  Year 2015 Publication PLoS Biology Abbreviated Journal PLoS Biol  
  Volume 13 Issue 5 Pages e1002160  
  Keywords (up) Animals; Commentary; *Circadian Rhythm; suprachiasmatic nuclei; melanopsin; retinal ganglion cells; entrainment; photoperiod  
  Abstract Circadian rhythms are an essential property of life on Earth. In mammals, these rhythms are coordinated by a small set of neurons, located in the suprachiasmatic nuclei (SCN). The environmental light/dark cycle synchronizes (entrains) the SCN via a distinct pathway, originating in a subset of photosensitive retinal ganglion cells (pRGCs) that utilize the photopigment melanopsin (OPN4). The pRGCs are also innervated by rods and cones and, so, are both endogenously and exogenously light sensitive. Accumulating evidence has shown that the circadian system is sensitive to ultraviolet (UV), blue, and green wavelengths of light. However, it was unclear whether colour perception itself can help entrain the SCN. By utilizing both behavioural and electrophysiological recording techniques, Walmsley and colleagues show that multiple photic channels interact and enhance the capacity of the SCN to synchronize to the environmental cycle. Thus, entrainment of the circadian system combines both environmental irradiance and colour information to ensure that internal and external time are appropriately aligned.  
  Address Laboratory for Neurophysiology, Department of Molecular Cell Biology, Leiden University medical School, Leiden, The Netherlands  
  Corporate Author Thesis  
  Publisher PLOS Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1544-9173 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:25996907; PMCID:PMC4440787 Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 1183  
Permanent link to this record
 

 
Author van der Burght, B.W.; Hansen, M.; Olsen, J.; Zhou, J.; Wu, Y.; Nissen, M.H.; Sparrow, J.R. url  doi
openurl 
  Title Early changes in gene expression induced by blue light irradiation of A2E-laden retinal pigment epithelial cells Type Journal Article
  Year 2013 Publication Acta Ophthalmologica Abbreviated Journal Acta Ophthalmol  
  Volume 91 Issue 7 Pages e537-45  
  Keywords (up) Apoptosis; Cell Line; Cell Survival; Gene Expression Regulation/*physiology; Humans; Light; Lipofuscin/genetics; Oligonucleotide Array Sequence Analysis; Principal Component Analysis; Pyridinium Compounds; RNA, Messenger/genetics; Real-Time Polymerase Chain Reaction; Retinal Pigment Epithelium/metabolism/pathology/*radiation effects; Retinoids/*genetics; Transcriptome; A2e; age-related macular degeneration; apoptosis; complement cascade; gene expression; retinal pigment epithelial cells; blue light; retinal pigment epithelial; epigenetics  
  Abstract PURPOSE: Accumulation of bisretinoids as lipofuscin in retinal pigment epithelial (RPE) cells is implicated in the pathogenesis of some blinding diseases including age-related macular degeneration (AMD). To identify genes whose expression may change under conditions of bisretinoid accumulation, we investigated the differential gene expression in RPE cells that had accumulated the lipofuscin fluorophore A2E and were exposed to blue light (430 nm). METHODS: A2E-laden RPE cells were exposed to blue light (A2E/430 nm) at various time intervals. Cell death was quantified using Dead Red staining, and RNA levels for the entire genome was determined using DNA microarrays (Affymetrix GeneChip Human Genome 2.0 Plus). Array results for selected genes were confirmed by real-time reverse-transcriptase polymerase chain reaction. RESULTS: Principal component analysis revealed that the A2E-laden RPE cells irradiated with blue light were clearly distinguishable from the control samples. We found differential regulation of genes belonging to the following functional groups: transcription factors, stress response, apoptosis and immune response. Among the last mentioned were downregulation of four genes that coded for proteins that have an inhibitory effect on the complement cascade: (complement factor H, complement factor H-related 1, complement factor I and vitronectin) and of two belonging to the classical pathway (complement component 1, s subcomponent and complement component 1, r subcomponent). CONCLUSION: This study demonstrates that blue light irradiation of A2E-laden RPE cells can alter the transcription of genes belonging to different functional pathways including stress response, apoptosis and the immune response. We suggest that these molecules may be associated to the pathogenesis of AMD and can potentially serve as future therapeutic targets.  
  Address Department of International Health, Immunology and Microbiology, Eye Research Unit, University of Copenhagen, Copenhagen, DenmarkDepartment of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, DenmarkDepartment of Ophthalmology, Columbia University, New York, New York, USA  
  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 1755-375X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23742627 Approved no  
  Call Number IDA @ john @ Serial 346  
Permanent link to this record
 

 
Author Bapary, M.A.J.; Takano, J.-I.; Soma, S.; Sankai, T. url  doi
openurl 
  Title Effect of blue LED light and antioxidants potential in a somatic cell Type Journal Article
  Year 2019 Publication Cell Biology International Abbreviated Journal Cell Biol Int  
  Volume in press Issue Pages  
  Keywords (up) Cells; Biology  
  Abstract Light is an indispensable part of routine laboratory works in which conventional light is generally used. Light-emitting diodes (LEDs) have come to replace the conventional light thus could be a potent target in biomedical studies. Since blue light is a major component of visible light wavelength, in this study, using a somatic cell from African green monkey kidney, we assessed the possible consequences of blue spectra of LED light in future animal experiments and proposed a potent mitigation against light induced damages. COS-7 cells were exposed to blue LED light (450 nm) and the growth and DNA damage were assessed at different exposure times. A higher suppression in cell growth and viability was observed under a longer period of blue LED light exposure. The number of apoptotic cells increased as light exposure time was prolonged. Reactive oxygen species generation was also elevated in accordance to the extension of light exposure times. A comparison to dark-maintained cells revealed that the upregulation of ROS by blue LED light plays a significant role in causing cellular dysfunction in DNA in a time-dependent manner. In turn, antioxidant treatment has shown to improve the cell growth and viability under blue LED light conditions. This indicates that antioxidants are potential against blue LED light-induced somatic cell damage. It is expected that this study will contribute to the understanding of the basic mechanism of somatic cell death under visible light and to maximize the beneficial use of LED light in future animal experiments. This article is protected by copyright. All rights reserved.  
  Address Tsukuba Primate Research Center, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki, Japan  
  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 1065-6995 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30958611 Approved no  
  Call Number GFZ @ kyba @ Serial 2328  
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Author Lucas, R.J.; Peirson, S.N.; Berson, D.M.; Brown, T.M.; Cooper, H.M.; Czeisler, C.A.; Figueiro, M.G.; Gamlin, P.D.; Lockley, S.W.; O'Hagan, J.B.; Price, L.L.A.; Provencio, I.; Skene, D.J.; Brainard, G.C. url  doi
openurl 
  Title Measuring and using light in the melanopsin age Type Journal Article
  Year 2014 Publication Trends in Neurosciences Abbreviated Journal Trends Neurosci  
  Volume 37 Issue 1 Pages 1-9  
  Keywords (up) Editorial; Animals; Circadian Rhythm/physiology; Humans; Photoreceptor Cells/metabolism; Phototherapy/*trends; Retinal Ganglion Cells/metabolism; Rod Opsins/*physiology  
  Abstract Light is a potent stimulus for regulating circadian, hormonal, and behavioral systems. In addition, light therapy is effective for certain affective disorders, sleep problems, and circadian rhythm disruption. These biological and behavioral effects of light are influenced by a distinct photoreceptor in the eye, melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs), in addition to conventional rods and cones. We summarize the neurophysiology of this newly described sensory pathway and consider implications for the measurement, production, and application of light. A new light-measurement strategy taking account of the complex photoreceptive inputs to these non-visual responses is proposed for use by researchers, and simple suggestions for artificial/architectural lighting are provided for regulatory authorities, lighting manufacturers, designers, and engineers.  
  Address Department of Neurology, Thomas Jefferson University, Philidelphia, PA, USA. Electronic address: George.Brainard@jefferson.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 0166-2236 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:24287308 Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 457  
Permanent link to this record
 

 
Author Cajochen, C.; Munch, M.; Kobialka, S.; Krauchi, K.; Steiner, R.; Oelhafen, P.; Orgul, S.; Wirz-Justice, A. url  doi
openurl 
  Title High sensitivity of human melatonin, alertness, thermoregulation, and heart rate to short wavelength light Type Journal Article
  Year 2005 Publication The Journal of Clinical Endocrinology and Metabolism Abbreviated Journal J Clin Endocrinol Metab  
  Volume 90 Issue 3 Pages 1311-1316  
  Keywords (up) Human Health; Adult; Body Temperature Regulation/physiology/*radiation effects; Circadian Rhythm/physiology/radiation effects; Color; Heart Rate/physiology/*radiation effects; Humans; *Light; Male; Melatonin/*metabolism; Retinal Cone Photoreceptor Cells/physiology; Sleep Stages/physiology/radiation effects; Wakefulness/physiology/*radiation effects  
  Abstract Light can elicit acute physiological and alerting responses in humans, the magnitude of which depends on the timing, intensity, and duration of light exposure. Here, we report that the alerting response of light as well as its effects on thermoregulation and heart rate are also wavelength dependent. Exposure to 2 h of monochromatic light at 460 nm in the late evening induced a significantly greater melatonin suppression than occurred with 550-nm monochromatic light, concomitant with a significantly greater alerting response and increased core body temperature and heart rate ( approximately 2.8 x 10(13) photons/cm(2)/sec for each light treatment). Light diminished the distal-proximal skin temperature gradient, a measure of the degree of vasoconstriction, independent of wavelength. Nonclassical ocular photoreceptors with peak sensitivity around 460 nm have been found to regulate circadian rhythm function as measured by melatonin suppression and phase shifting. Our findings-that the sensitivity of the human alerting response to light and its thermoregulatory sequelae are blue-shifted relative to the three-cone visual photopic system-indicate an additional role for these novel photoreceptors in modifying human alertness, thermophysiology, and heart rate.  
  Address Centre for Chronobiology, Psychiatric University Clinic, Wilhelm Kleinstr. 27, CH-4025 Basel, Switzerland. christian.cajochen@pukbasel.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 0021-972X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15585546 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 728  
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