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Author Filipski, E.; Subramanian, P.; Carriere, J.; Guettier, C.; Barbason, H.; Levi, F. url  doi
openurl 
  Title Circadian disruption accelerates liver carcinogenesis in mice Type Journal Article
  Year 2009 Publication Mutation Research Abbreviated Journal Mutat Res  
  Volume 680 Issue 1-2 Pages 95-105  
  Keywords Human Health; Animals; Alanine Transaminase/blood; Animals; Aspartate Aminotransferases/blood; Bile Duct Neoplasms/chemically induced/pathology; Bile Ducts, Intrahepatic/drug effects/pathology; Body Weight/drug effects; Carcinogens/administration & dosage/*toxicity; Carcinoma, Hepatocellular/chemically induced/pathology; Cholangiocarcinoma/chemically induced/pathology; Circadian Rhythm/*drug effects; Diethylnitrosamine/administration & dosage/*toxicity; Dose-Response Relationship, Drug; Injections, Intraperitoneal; Liver/drug effects/pathology; Liver Neoplasms/blood/*chemically induced/pathology; Male; Mice; Neoplasms, Multiple Primary/chemically induced/pathology; Sarcoma/chemically induced/pathology; Time Factors  
  Abstract BACKGROUND: The circadian timing system rhythmically controls behavior, physiology, cellular proliferation and xenobiotic metabolism over the 24-h period. The suprachiasmatic nuclei in the hypothalamus coordinate the molecular clocks in most mammalian cells through an array of circadian physiological rhythms including rest-activity, body temperature, feeding patterns and hormonal secretions. As a result, shift work that involves circadian disruption is probably carcinogenic in humans. In experimental models, chronic jet-lag (CJL) suppresses rest-activity and body temperature rhythms and accelerates growth of two transplantable tumors in mice. CJL also suppresses or significantly alters the expression rhythms of clock genes in liver and tumors. Circadian clock disruption from CJL downregulates p53 and upregulates c-Myc, thus favoring cellular proliferation. Here, we investigate the role of CJL as a tumor promoter in mice exposed to the hepatic carcinogen, diethylnitrosamine (DEN). METHODS: In experiment 1 (Exp 1), the dose-dependent carcinogenicity of chronic intraperitoneal (i.p.) administration of DEN was explored in mice. In Exp 2, mice received DEN at 10 mg/kg/day (cumulative dose: 243 mg/kg), then were randomized to remain in a photoperiodic regimen where 12 h of light alternates with 12 h of darkness (LD 12:12) or to be submitted to CJL (8-h advance of light onset every 2 days). Rest-activity and body temperature were monitored. Serum liver enzymes were determined repeatedly. Mice were sacrificed and examined for neoplastic lesions at 10 months. RESULTS: In Exp 1, DEN produced liver cancers in all the mice receiving 10 mg/kg/day. In Exp 2, mice on CJL had increased mean plasma levels of aspartate aminotransferase and more liver tumors as compared to LD mice at approximately 10 months (p = 0.005 and 0.028, respectively). The mean diameter of the largest liver tumor was twice as large in CJL vs LD mice (8.5 vs 4.4 mm, p = 0.027). In LD, a single histologic tumor type per liver was observed. In CJL, up to four different types were associated in the same liver (hepatocellular- or cholangio-carcinomas, sarcomas or mixed tumors). DEN itself markedly disrupted the circadian rhythms in rest-activity and body temperature in all the mice. DEN-induced disruption was prolonged for >or= 3 months by CJL exposure. CONCLUSIONS: The association of circadian disruption with chronic DEN exposure suggests that circadian clocks actively control the mechanisms of liver carcinogenesis in mice. Persistent circadian coordination may further be critical for slowing down and/or reverting cancer development after carcinogen exposure.  
  Address (up) INSERM, U776 Rythmes Biologiques et Cancers, Hopital Paul Brousse, Villejuif F-94807, France  
  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 0027-5107 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:19833225 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 747  
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Author Zukauskas, A.; Vaicekauskas, R.; Vitta, P. url  doi
openurl 
  Title Optimization of solid-state lamps for photobiologically friendly mesopic lighting Type Journal Article
  Year 2012 Publication Applied Optics Abbreviated Journal Appl Opt  
  Volume 51 Issue 35 Pages 8423-8432  
  Keywords Lighting Systems; Circadian Rhythm; Color; Equipment Design; Humans; Light; *Lighting; Melatonin/metabolism; Photobiology/*methods; Semiconductors; Time Factors; Vision, Ocular  
  Abstract The circadian and visual-performance-based mesopic systems of photometry were applied for the optimization of the spectral power distributions (SPDs) of the solid-state sources of light for low-illuminance lighting applications. At mesopic adaptation luminances typical of outdoor lighting (0.1-2 cd/m(2)), the optimal SPDs were obtained through the minimization of the mesopic circadian action factor, which is the ratio of the circadian efficacy of radiation to mesopic luminous efficacy of radiation. For correlated color temperatures below ~3000 K, the optimized dichromatic light-emitting diodes (LEDs) are shown to pose a lower circadian hazard than high-pressure sodium lamps and common warm white LEDs; also they are potentially more efficacious and have acceptable color rendition properties under mesopic conditions.  
  Address (up) Institute of Applied Research, Vilnius University, Sauletekio al. 9-III, Vilnius LT-10222, Lithuania. arturas.zukauskas@ff.vu.lt  
  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 0003-6935 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23262538 Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 448  
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Author Wood, B.; Rea, M.S.; Plitnick, B.; Figueiro, M.G. url  doi
openurl 
  Title Light level and duration of exposure determine the impact of self-luminous tablets on melatonin suppression Type Journal Article
  Year 2013 Publication Applied Ergonomics Abbreviated Journal Appl Ergon  
  Volume 44 Issue 2 Pages 237-240  
  Keywords Adolescent; *Computers, Handheld; Female; Humans; Light/*adverse effects; Male; Melatonin/*biosynthesis; Photoperiod; Saliva/*metabolism; Sleep/radiation effects; Time Factors; Young Adult; melatonin  
  Abstract Exposure to light from self-luminous displays may be linked to increased risk for sleep disorders because these devices emit optical radiation at short wavelengths, close to the peak sensitivity of melatonin suppression. Thirteen participants experienced three experimental conditions in a within-subjects design to investigate the impact of self-luminous tablet displays on nocturnal melatonin suppression: 1) tablets-only set to the highest brightness, 2) tablets viewed through clear-lens goggles equipped with blue light-emitting diodes that provided 40 lux of 470-nm light at the cornea, and 3) tablets viewed through orange-tinted glasses (dark control; optical radiation <525 nm approximately 0). Melatonin suppressions after 1-h and 2-h exposures to tablets viewed with the blue light were significantly greater than zero. Suppression levels after 1-h exposure to the tablets-only were not statistically different than zero; however, this difference reached significance after 2 h. Based on these results, display manufacturers can determine how their products will affect melatonin levels and use model predictions to tune the spectral power distribution of self-luminous devices to increase or to decrease stimulation to the circadian system.  
  Address (up) Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, Troy, NY 12180, USA. woodb5@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 0003-6870 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:22850476 Approved no  
  Call Number IDA @ john @ Serial 136  
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Author Santhi, N.; Thorne, H.C.; van der Veen, D.R.; Johnsen, S.; Mills, S.L.; Hommes, V.; Schlangen, L.J.M.; Archer, S.N.; Dijk, D.-J. url  doi
openurl 
  Title The spectral composition of evening light and individual differences in the suppression of melatonin and delay of sleep in humans Type Journal Article
  Year 2012 Publication Journal of Pineal Research Abbreviated Journal J Pineal Res  
  Volume 53 Issue 1 Pages 47-59  
  Keywords Human Health; Adult; *Circadian Clocks; Cross-Sectional Studies; Electroencephalography; Female; Humans; Male; Melatonin/*metabolism; Photic Stimulation; *Photoperiod; Rod Opsins/*metabolism; *Sleep; *Sleep Disorders, Circadian Rhythm/etiology/metabolism/physiopathology; Time Factors  
  Abstract The effect of light on circadian rhythms and sleep is mediated by a multi-component photoreceptive system of rods, cones and melanopsin-expressing intrinsically photosensitive retinal ganglion cells. The intensity and spectral sensitivity characteristics of this system are to be fully determined. Whether the intensity and spectral composition of light exposure at home in the evening is such that it delays circadian rhythms and sleep also remains to be established. We monitored light exposure at home during 6-8wk and assessed light effects on sleep and circadian rhythms in the laboratory. Twenty-two women and men (23.1+/-4.7yr) participated in a six-way, cross-over design using polychromatic light conditions relevant to the light exposure at home, but with reduced, intermediate or enhanced efficacy with respect to the photopic and melanopsin systems. The evening rise of melatonin, sleepiness and EEG-assessed sleep onset varied significantly (P<0.01) across the light conditions, and these effects appeared to be largely mediated by the melanopsin, rather than the photopic system. Moreover, there were individual differences in the sensitivity to the disruptive effect of light on melatonin, which were robust against experimental manipulations (intra-class correlation=0.44). The data show that light at home in the evening affects circadian physiology and imply that the spectral composition of artificial light can be modified to minimize this disruptive effect on sleep and circadian rhythms. These findings have implications for our understanding of the contribution of artificial light exposure to sleep and circadian rhythm disorders such as delayed sleep phase disorder.  
  Address (up) Surrey Sleep Research Centre, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK. n.santhi@surrey.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 0742-3098 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:22017511 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 802  
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Author Dukic, T.; Ahlstrom, C.; Patten, C.; Kettwich, C.; Kircher, K. url  doi
openurl 
  Title Effects of electronic billboards on driver distraction Type Journal Article
  Year 2013 Publication Traffic Injury Prevention Abbreviated Journal Traffic Inj Prev  
  Volume 14 Issue 5 Pages 469-476  
  Keywords Adult; Advertising as Topic/*methods; *Attention; Automobile Driving/*psychology; Eye Movements; Humans; Middle Aged; Psychomotor Performance; Sweden; Time Factors  
  Abstract OBJECTIVE: There is an increase in electronic advertising billboards along major roads, which may cause driver distraction due to the highly conspicuous design of the electronic billboards. Yet limited research on the impact of electronic billboards on driving performance and driver behavior is available. The Swedish Transport Administration recently approved the installation of 12 electronic billboards for a trial period along a 3-lane motorway with heavy traffic running through central Stockholm, Sweden. The aim of this study was to evaluate the effect of these electronic billboards on visual behavior and driving performance. METHOD: A total of 41 drivers were recruited to drive an instrumented vehicle passing 4 of the electronic billboards during day and night conditions. A driver was considered visually distracted when looking at a billboard continuously for more than 2 s or if the driver looked away from the road for a high percentage of time. Dependent variables were eye-tracking measures and driving performance measures. RESULTS: The visual behavior data showed that drivers had a significantly longer dwell time, a greater number of fixations, and longer maximum fixation duration when driving past an electronic billboard compared to other signs on the same road stretches. No differences were found for the factors day/night, and no effect was found for the driving behavior data. CONCLUSION: Electronic billboards have an effect on gaze behavior by attracting more and longer glances than regular traffic signs. Whether the electronic billboards attract too much attention and constitute a traffic safety hazard cannot be answered conclusively based on the present data.  
  Address (up) Swedish National Road and Transport Research Institute, Linkoping, Sweden. tania.dukic@vti.se  
  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 1538-9588 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23682577 Approved no  
  Call Number IDA @ john @ Serial 247  
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