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Author Bedrosian, T.A.; Fonken, L.K.; Walton, J.C.; Nelson, R.J. url  doi
openurl 
  Title Chronic exposure to dim light at night suppresses immune responses in Siberian hamsters Type Journal Article
  Year 2011 Publication (up) Biology Letters Abbreviated Journal Biol Lett  
  Volume 7 Issue 3 Pages 468-471  
  Keywords Animals; Blood Bactericidal Activity/immunology; Circadian Rhythm; Cricetinae; Fever/immunology; Hypersensitivity, Delayed/immunology; *Immunity; Light/*adverse effects; Lipopolysaccharides; Locomotion; Phodopus/*immunology  
  Abstract Species have been adapted to specific niches optimizing survival and reproduction; however, urbanization by humans has dramatically altered natural habitats. Artificial light at night (LAN), termed 'light pollution', is an often overlooked, yet increasing disruptor of habitats, which perturbs physiological processes that rely on precise light information. For example, LAN alters the timing of reproduction and activity in some species, which decreases the odds of successful breeding and increases the threat of predation for these individuals, leading to reduced fitness. LAN also suppresses immune function, an important proxy for survival. To investigate the impact of LAN in a species naive to light pollution in its native habitat, immune function was examined in Siberian hamsters derived from wild-caught stock. After four weeks exposure to dim LAN, immune responses to three different challenges were assessed: (i) delayed-type hypersensitivity (DTH), (ii) lipopolysaccharide-induced fever, and (iii) bactericide activity of blood. LAN suppressed DTH response and reduced bactericide activity of blood after lipopolysaccharide treatment, in addition to altering daily patterns of locomotor activity, suggesting that human encroachment on habitats via night-time lighting may inadvertently compromise immune function and ultimately fitness.  
  Address Department of Neuroscience, The Ohio State University Medical Center, Columbus, OH 43210, USA. tracy.bedrosian@osumc.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1744-9561 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21270021; PMCID:PMC3097873 Approved no  
  Call Number IDA @ john @ Serial 90  
Permanent link to this record
 

 
Author Kohyama, J. url  doi
openurl 
  Title A newly proposed disease condition produced by light exposure during night: asynchronization Type Journal Article
  Year 2009 Publication (up) Brain & Development Abbreviated Journal Brain Dev  
  Volume 31 Issue 4 Pages 255-273  
  Keywords Adolescent; Adult; Biological Clocks; Child; Child, Preschool; Chronotherapy; Circadian Rhythm/physiology; Complementary Therapies; Humans; Infant; Japan; *Light; Motor Activity; Phototherapy; Serotonin/metabolism; Sleep; Sleep Disorders, Circadian Rhythm/*physiopathology/therapy; Students; Wakefulness  
  Abstract The bedtime of preschoolers/pupils/students in Japan has become progressively later with the result sleep duration has become progressively shorter. With these changes, more than half of the preschoolers/pupils/students in Japan recently have complained of daytime sleepiness, while approximately one quarter of junior and senior high school students in Japan reportedly suffer from insomnia. These preschoolers/pupils/students may be suffering from behaviorally induced insufficient sleep syndrome due to inadequate sleep hygiene. If this diagnosis is correct, they should be free from these complaints after obtaining sufficient sleep by avoiding inadequate sleep hygiene. However, such a therapeutic approach often fails. Although social factors are often involved in these sleep disturbances, a novel clinical notion--asynchronization--can further a deeper understanding of the pathophysiology of these disturbances. The essence of asynchronization is a disturbance in various aspects (e.g., cycle, amplitude, phase and interrelationship) of the biological rhythms that normally exhibit circadian oscillation, presumably involving decreased activity of the serotonergic system. The major trigger of asynchronization is hypothesized to be a combination of light exposure during the night and a lack of light exposure in the morning. In addition to basic principles of morning light and an avoidance of nocturnal light exposure, presumable potential therapeutic approaches for asynchronization involve both conventional ones (light therapy, medications (hypnotics, antidepressants, melatonin, vitamin B12), physical activation, chronotherapy) and alternative ones (kampo, pulse therapy, direct contact, control of the autonomic nervous system, respiration (qigong, tanden breathing), chewing, crawling). A morning-type behavioral preference is described in several of the traditional textbooks for good health. The author recommends a morning-type behavioral lifestyle as a way to reduce behavioral/emotional problems, and to lessen the likelihood of falling into asynchronization.  
  Address Department of Pediatrics, Tokyo Kita Shakai Hoken Hospital, 4-17-56 Akabanedai, Tokyo, Japan. j-kohyama@tokyokita-jadecom.jp  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0387-7604 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:18757146 Approved no  
  Call Number IDA @ john @ Serial 297  
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Author Raiewski, E.E.; Elliott, J.A.; Evans, J.A.; Glickman, G.L.; Gorman, M.R. url  doi
openurl 
  Title Twice daily melatonin peaks in Siberian but not Syrian hamsters under 24 h light:dark:light:dark cycles Type Journal Article
  Year 2012 Publication (up) Chronobiology International Abbreviated Journal Chronobiol Int  
  Volume 29 Issue 9 Pages 1206-1215  
  Keywords Animals; Circadian Rhythm/*physiology; Cricetinae; Male; Melatonin/blood/*secretion; Mesocricetus/blood/*physiology; Motor Activity/physiology; Phodopus/blood/*physiology; Photoperiod; Species Specificity  
  Abstract The daily pattern of blood-borne melatonin varies seasonally under the control of a multi-oscillator circadian pacemaker. Here we examine patterns of melatonin secretion and locomotor activity in Siberian and Syrian hamsters entrained to bimodal LDLD8:4:8:4 and LD20:4 lighting schedules that facilitate novel temporal arrangements of component circadian oscillators. Under LDLD, both species robustly bifurcated wheel-running activity in distinct day scotophase (DS) and night scotophase (NS) bouts. Siberian hamsters displayed significant melatonin increases during each scotophase in LDLD, and in the single daily scotophase of LD20:4. The bimodal melatonin secretion pattern persisted in acutely extended 16 h scotophases. Syrian hamsters, in contrast, showed no significant increases in plasma melatonin during either scotophase of LDLD8:4:8:4 or in LD20:4. In this species, detectable levels were observed only when the DS of LDLD was acutely extended to yield 16 h of darkness. Established species differences in the phase lag of nocturnal melatonin secretion relative to activity onset may underlie the above contrast: In non-bifurcated entrainment to 24 h LD cycles, Siberian hamsters show increased melatonin secretion within approximately 2 h after activity onset, whereas in Syrian hamsters, detectable melatonin secretion phase lags activity onset and the L/D transition by at least 4 h. The present results provide new evidence indicating multi-oscillator regulation of the waveform of melatonin secretion, specifically, the circadian control of the onset, offset and duration of nocturnal secretion.  
  Address Department of Psychology, and Center for Chronobiology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0109, USA. eraiewski@ucsd.edu  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0742-0528 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23003567 Approved no  
  Call Number IDA @ john @ Serial 85  
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Author Kempinger, L.; Dittmann, R.; Rieger, D.; Helfrich-Forster, C. url  doi
openurl 
  Title The nocturnal activity of fruit flies exposed to artificial moonlight is partly caused by direct light effects on the activity level that bypass the endogenous clock Type Journal Article
  Year 2009 Publication (up) Chronobiology International Abbreviated Journal Chronobiol Int  
  Volume 26 Issue 2 Pages 151-166  
  Keywords ARNTL Transcription Factors; Animals; Basic Helix-Loop-Helix Transcription Factors/genetics/metabolism; Behavior, Animal/physiology; Biological Clocks/*physiology; CLOCK Proteins; Circadian Rhythm/*physiology; Darkness; Drosophila Proteins/genetics/metabolism; Drosophila melanogaster/*physiology; *Light; *Moon; Motor Activity/*physiology; Nuclear Proteins/genetics/metabolism; Period Circadian Proteins; Photoperiod; Transcription Factors/genetics/metabolism  
  Abstract Artificial moonlight was recently shown to shift the endogenous clock of fruit flies and make them nocturnal. To test whether this nocturnal activity is partly due to masking effects of light, we exposed the clock-mutants per(01), tim(01), per(01);tim(01), cyc(01), and Clk(JRK) to light/dark and light/dim-light cycles and determined the activity level during the day and night. We found that under moonlit nights, all clock mutants shifted their activity significantly into the night, suggesting that this effect is independent of the clock. We also recorded the flies under continuous artificial moonlight and darkness to judge the effect of dim constant light on the activity level. All mutants, except Clk(JRK) flies, were significantly more active under artificial moonlight conditions than under complete darkness. Unexpectedly, we found residual rhythmicity of per(01) and especially tim(01) mutants under these conditions, suggesting that TIM and especially PER retained some activity in the absence of its respective partner. Nevertheless, as even the double mutants and the cyc(01) and Clk(JRK) mutants shifted their activity into the night, we conclude that dim light stimulates the activity of fruit flies in a clock-independent manner. Thus, nocturnal light has a twofold influence on flies: it shifts the circadian clock, and it increases nocturnal activity independently of the clock. The latter was also observed in some primates by others and might therefore be of a more general validity.  
  Address Institute of Zoology, University of Regensburg, Regensburg, Germany  
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  Series Volume Series Issue Edition  
  ISSN 0742-0528 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:19212834 Approved no  
  Call Number IDA @ john @ Serial 113  
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Author Dacke, M.; Baird, E.; Byrne, M.; Scholtz, C.H.; Warrant, E.J. url  doi
openurl 
  Title Dung beetles use the Milky Way for orientation Type Journal Article
  Year 2013 Publication (up) Current Biology : CB Abbreviated Journal Curr Biol  
  Volume 23 Issue 4 Pages 298-300  
  Keywords Animals; Beetles/*physiology; *Behavior, Animal; Cues; Feces; *Galaxies; Locomotion; Moon; Motor Activity; Orientation/*physiology; *Stars, Celestial; Vision, Ocular/physiology; Milky Way; insects  
  Abstract When the moon is absent from the night sky, stars remain as celestial visual cues. Nonetheless, only birds, seals, and humans are known to use stars for orientation. African ball-rolling dung beetles exploit the sun, the moon, and the celestial polarization pattern to move along straight paths, away from the intense competition at the dung pile. Even on clear moonless nights, many beetles still manage to orientate along straight paths. This led us to hypothesize that dung beetles exploit the starry sky for orientation, a feat that has, to our knowledge, never been demonstrated in an insect. Here, we show that dung beetles transport their dung balls along straight paths under a starlit sky but lose this ability under overcast conditions. In a planetarium, the beetles orientate equally well when rolling under a full starlit sky as when only the Milky Way is present. The use of this bidirectional celestial cue for orientation has been proposed for vertebrates, spiders, and insects, but never proven. This finding represents the first convincing demonstration for the use of the starry sky for orientation in insects and provides the first documented use of the Milky Way for orientation in the animal kingdom.  
  Address Department of Biology, Lund University, 223 62 Lund, Sweden. marie.dacke@biol.lu.se  
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  Series Volume Series Issue Edition  
  ISSN 0960-9822 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23352694 Approved no  
  Call Number IDA @ john @ Serial 116  
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