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Author Ostrin, L.A. url  doi
openurl 
  Title Ocular and systemic melatonin and the influence of light exposure Type Journal Article
  Year 2018 Publication Clinical & Experimental Optometry Abbreviated Journal Clin Exp Optom  
  Volume in press Issue Pages in press  
  Keywords Vision; Review; Human Health  
  Abstract Melatonin is a neurohormone known to modulate a wide range of circadian functions, including sleep. The synthesis and release of melatonin from the pineal gland is heavily influenced by light stimulation of the retina, particularly through the intrinsically photosensitive retinal ganglion cells. Melatonin is also synthesised within the eye, although to a much lesser extent than in the pineal gland. Melatonin acts directly on ocular structures to mediate a variety of diurnal rhythms and physiological processes within the eye. The interactions between melatonin, the eye, and visual function have been the subject of a considerable body of recent research. This review is intended to provide a broad introduction for eye-care practitioners and researchers to the topic of melatonin and the eye. The first half of the review describes the anatomy and physiology of melatonin production: how visual inputs affect the pineal production of melatonin; how melatonin is involved in a variety of diurnal rhythms within the eye, including photoreceptor disc shedding, neuronal sensitivity, and intraocular pressure control; and melatonin production and physiological roles in retina, ciliary body, lens and cornea. The second half of the review describes clinical implications of light/melatonin interactions. These include light exposure and photoreceptor contributions in melatonin suppression, leading to consideration of how blue blockers, cataract, and light therapy might affect sleep and mood in patients. Additionally, the interactions between melatonin, sleep and refractive error development are discussed. A better understanding of environmental factors that affect melatonin and subsequent effects on physiological processes will allow clinicians to develop treatments and recommend modifiable behaviours to improve sleep, increase daytime alertness, and regulate ocular and systemic processes related to melatonin.  
  Address University of Houston College of Optometry, Houston, Texas, 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 0816-4622 ISBN Medium  
  Area Expedition Conference  
  Notes (down) PMID:30074278 Approved no  
  Call Number GFZ @ kyba @ Serial 1986  
Permanent link to this record
 

 
Author Pilz, L.K.; Levandovski, R.; Oliveira, M.A.B.; Hidalgo, M.P.; Roenneberg, T. url  doi
openurl 
  Title Sleep and light exposure across different levels of urbanisation in Brazilian communities Type Journal Article
  Year 2018 Publication Scientific Reports Abbreviated Journal Sci Rep  
  Volume 8 Issue 1 Pages 11389  
  Keywords Human Health; Sleep  
  Abstract Quilombos are settlements originally founded by Africans and African descendants (Quilombolas) in remote parts of Brazil to escape slavery. Due to individual histories, Quilombos nowadays exhibit different states of industrialisation, making them ideal for studying the influence of electrification on daily behaviour. In a comparative approach, we aimed to understand whether and how human sleep changes with the introduction of artificial light. We investigated daily rest-activity-rhythms and sleep-patterns in the Quilombolas' by both wrist actimetry and the Munich ChronoType Questionnaire (MCTQ; the results of these two instruments correlated highly). Seven communities (MCTQ: N = 213/actimetry: N = 125) were compared in this study. Light exposure, phase of activity, sleep timing and duration differ across communities with various levels of urbanisation and histories of access to electricity. People living without electricity and those, who acquired it only very recently on average sleep earlier than those in more urbanised communities (mid-sleep about 1 hour earlier); sleep duration tends to be longer. Our results and those of others show that use of electricity and modern lifestyles have changed sleep behaviour. To understand the consequences of these changes for health, further studies are warranted.  
  Address Visiting Professor at UFRGS/CAPES, Porto Alegre, RS, Brazil. roenneberg@lmu.de  
  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 2045-2322 ISBN Medium  
  Area Expedition Conference  
  Notes (down) PMID:30061685 Approved no  
  Call Number GFZ @ kyba @ Serial 1968  
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Author Dominoni, D.M.; de Jong, M.; Bellingham, M.; O'Shaughnessy, P.; van Oers, K.; Robinson, J.; Smith, B.; Visser, M.E.; Helm, B. url  doi
openurl 
  Title Dose-response effects of light at night on the reproductive physiology of great tits (Parus major): Integrating morphological analyses with candidate gene expression Type Journal Article
  Year 2018 Publication Journal of Experimental Zoology. Part A, Ecological and Integrative Physiology Abbreviated Journal J Exp Zool A Ecol Integr Physiol  
  Volume in press Issue Pages in press  
  Keywords Animals  
  Abstract Artificial light at night (ALAN) is increasingly recognized as a potential threat to wildlife and ecosystem health. Among the ecological effects of ALAN, changes in reproductive timing are frequently reported, but the mechanisms underlying this relationship are still poorly understood. Here, we experimentally investigated these mechanisms by assessing dose-dependent photoperiodic responses to ALAN in the great tit (Parus major). We individually exposed photosensitive male birds to one of three nocturnal light levels (0.5, 1.5, and 5 lux), or to a dark control. Subsequent histological and molecular analyses on their testes indicated a dose-dependent reproductive response to ALAN. Specifically, different stages of gonadal growth were activated after exposure to different levels of light at night. mRNA transcript levels of genes linked to the development of germ cells (stra8 and spo11) were increased under 0.5 lux compared to the dark control. The 0.5 and 1.5 lux groups showed slight increases in testis size and transcript levels associated with steroid synthesis (lhr and hsd3b1) and spermatogenesis (fshr, wt1, sox9, and cldn11), although spermatogenesis was not detected in histological analysis. In contrast, all birds under 5 lux had 10 to 30 times larger testes than birds in all other groups, with a parallel strong increase in mRNA transcript levels and clear signs of spermatogenesis. Across treatments, the volume of the testes was generally a good predictor of testicular transcript levels. Overall, our findings indicate that even small changes in nocturnal light intensity can increase, or decrease, effects on the reproductive physiology of wild organisms.  
  Address GELIFES, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands  
  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 2471-5638 ISBN Medium  
  Area Expedition Conference  
  Notes (down) PMID:30058288 Approved no  
  Call Number GFZ @ kyba @ Serial 1964  
Permanent link to this record
 

 
Author Sanders, D.; Kehoe, R.; Cruse, D.; van Veen, F.J.F.; Gaston, K.J. url  doi
openurl 
  Title Low Levels of Artificial Light at Night Strengthen Top-Down Control in Insect Food Web Type Journal Article
  Year 2018 Publication Current Biology : CB Abbreviated Journal Curr Biol  
  Volume 28 Issue 15 Pages 2474-2478.e3  
  Keywords Ecology; Animals  
  Abstract Artificial light has transformed the nighttime environment of large areas of the earth, with 88% of Europe and almost 50% of the United States experiencing light-polluted night skies [1]. The consequences for ecosystems range from exposure to high light intensities in the vicinity of direct light sources to the very widespread but lower lighting levels further away [2]. While it is known that species exhibit a range of physiological and behavioral responses to artificial nighttime lighting [e.g., 3-5], there is a need to gain a mechanistic understanding of whole ecological community impacts [6, 7], especially to different light intensities. Using a mesocosm field experiment with insect communities, we determined the impact of intensities of artificial light ranging from 0.1 to 100 lux on different trophic levels and interactions between species. Strikingly, we found the strongest impact at low levels of artificial lighting (0.1 to 5 lux), which led to a 1.8 times overall reduction in aphid densities. Mechanistically, artificial light at night increased the efficiency of parasitoid wasps in attacking aphids, with twice the parasitism rate under low light levels compared to unlit controls. However, at higher light levels, parasitoid wasps spent longer away from the aphid host plants, diminishing this increased efficiency. Therefore, aphids reached higher densities under increased light intensity as compared to low levels of lighting, where they were limited by higher parasitoid efficiency. Our study highlights the importance of different intensities of artificial light in driving the strength of species interactions and ecosystem functions.  
  Address Environment and Sustainability Institute, University of Exeter, Penryn, Penryn, Cornwall TR10 9FE, 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 Expedition Conference  
  Notes (down) PMID:30057304 Approved no  
  Call Number GFZ @ kyba @ Serial 2518  
Permanent link to this record
 

 
Author Kumar, J.; Malik, S.; Bhardwaj, S.K.; Rani, S. url  doi
openurl 
  Title Bright light at night alters the perception of daylength in Indian weaver bird (Ploceus philippinus) Type Journal Article
  Year 2018 Publication Journal of Experimental Zoology. Part A, Ecological and Integrative Physiology Abbreviated Journal J Exp Zool A Ecol Integr Physiol  
  Volume 329 Issue 8-9 Pages 488-496  
  Keywords Animals  
  Abstract The brighter nights have posed new challenges to the wild species by affecting their temporal physiology. The present study on Indian weaver bird (Ploceus philippinus) investigated if exposure to bright light at different phases of night affects their clock-mediated daily functions. Birds were placed individually in specially designed activity cages under short days and long nights (8L:16D; L = 100 lux, D < 0.1 lux) for approximately 3 weeks (19 days). Thereafter, they were divided into four groups (n = 6-9), and given approximately 2 lux light either for the entire night (ZT 08-24; zeitgeber time 0 = time of light on; pattern A) or for 4 hr (pattern B), placed in 16 hr night such that its onset coincides with the onset of night (early night group, ZT 08-12), its end with the end of night (late night group, ZT 20-24), or the night was interrupted in the middle (midnight group, ZT 14-18). The results showed that bright light in entire night induced early onset of day activity and fragmented rest at night, however, if given at different phases of night, it made the days longer by delaying end (early night group) or advancing onset of daily activity (late night group). It also suppressed the melatonin levels and increased body temperature. These results suggest that bright light at night alters the perception of daylength and affects the underlying physiology. The findings may be useful in adopting a strategy for use of night light without disturbing species fitness in their environment.  
  Address Department of Zoology, University of Lucknow, Lucknow, India  
  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 2471-5638 ISBN Medium  
  Area Expedition Conference  
  Notes (down) PMID:30043408 Approved no  
  Call Number GFZ @ kyba @ Serial 1971  
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