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Hasegawa Yoshihiko Y Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, , Tokyo 113-0033, - - 2014
Circadian oscillation provides selection advantages through synchronization to the daylight cycle. However, a reliable clock must be designed through two conflicting properties: entrainability to synchronize internal time with periodic stimuli such as sunlight, and regularity to oscillate with a precise period. These two aspects do not easily coexist, because better ...
Owen Megan A MA Applied Animal Ecology, Institute for Conservation Research, San Diego Zoo Global, San Diego, - - 2013
Anthropogenic noise has become a pervasive feature of both marine and terrestrial habitats worldwide. While a comprehensive understanding of the biologically significant impacts of noise on wildlife is lacking, concerns regarding its influence persist. Noise is also a common feature in the zoological setting, and much can be learned regarding ...
Polidarová Lenka L 1Institute of Physiology, v.v.i., Academy of Sciences of the Czech - - 2013
Colonic morphology and function change significantly during ontogenesis. In mammals, many colonic physiological functions are temporally controlled by the circadian clock in the colon, which is entrained by the central circadian clock in the suprachiasmatic nuclei (SCN). The aim of this present study was to ascertain when and how the ...
Forbes-Stovall Jennifer J Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101, - - 2013
The unicellular green alga Chlamydomonas reinhardtii has long served as model organism for studies on the circadian clock. This clock is present in all eukaryotes and some prokaryotes allowing them to anticipate and take advantage of the daily oscillations in the environment. Although much is known about the circadian clock ...
McMahon Douglas G DG Department of Biological Sciences, Vanderbilt University, Nashville, TN, - - 2013
The retinal circadian system represents a unique structure. It contains a complete circadian system and thus the retina represents an ideal model to study fundamental questions of how neural circadian systems are organized and what signaling pathways are used to maintain synchrony of the different structures in the system. In ...
Keijzer Henry H Department of Clinical Chemistry and Hematology, Rijnstate Hospital, Arnhem, The Netherlands; Governor Kremers Centre, University Maastricht, The Netherlands. Electronic address: - - 2013
Treatment of circadian rhythm sleep disorders (CRSD) may include light therapy, chronotherapy and melatonin. Exogenous melatonin is increasingly being used in patients with insomnia or CRSD. Although pharmacopoeias and the European food safety authority (EFSA) recommend administering melatonin 1-2 h before desired bedtime, several studies have shown that melatonin is not always ...
Baidanoff Fernando M FM Laboratorio de Cronobiología, Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes/CONICET, Bernal, - - 2014
Most physiological processes in mammals are synchronized to the daily light:dark cycle by a circadian clock located in the hypothalamic suprachiasmatic nucleus. Signal transduction of light-induced phase advances of the clock is mediated through a neuronal nitric oxide synthase-guanilyl cyclase pathway. We have employed a novel nitric oxide-donor, N-nitrosomelatonin, to ...
Vaidya Anand T AT Department of Chemistry and Chemical Biology and Biotechnology Resource Center, Cornell University, Ithaca, NY - - 2013
Entrainment of circadian rhythms in higher organisms relies on light-sensing proteins that communicate to cellular oscillators composed of delayed transcriptional feedback loops. The principal photoreceptor of the fly circadian clock, Drosophila cryptochrome (dCRY), contains a C-terminal tail (CTT) helix that binds beside a FAD cofactor and is essential for light ...
Robertson James Brian JB Biology Department, Middle Tennessee State University, Murfreesboro, TN - - 2013
Exposure of cells to visible light in nature or in fluorescence microscopy often is considered to be relatively innocuous. However, using the yeast respiratory oscillation (YRO) as a sensitive measurement of metabolism, we find that non-UV visible light has a significant impact on yeast metabolism. Blue/green wavelengths of visible light ...
Adachi Akihito A - - 2013
The mammalian circadian oscillator is composed of interacting positive and negative transcription events. The clock proteins PER1 and PER2 play essential roles in a negative limb of the feedback loop that generates the circadian rhythm in mammals. In addition, the proteins CLOCK and BMAL1 (also known as ARNTL) form a ...
Lucas Robert J RJ Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK. Electronic address: - - 2014
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 ...
Bailey Matthew - - 2013
Virtually every eukaryotic cell has an endogenous circadian clock and a biological sex. These cell-based clocks have been conceptualized as oscillators whose phase can be reset by internal signals such as hormones, and external cues such as light. The present review highlights the inter-relationship between circadian clocks and sex differences. ...
Ladanov Mikhail - - 2013
Here we present a new design and FDTD simulations of light delivery by a nanowire-based intracellular endoscope. Nanowires can be used for minimally invasive and very local light delivery inside cells. One of the main challenges is coupling of light into the nanowire. We propose a new plasmonic coupler interface ...
Umetani Miki M Department of Electrical Engineering and Biological Science, Waseda University, TWIns, Tokyo, - - 2014
Cyanobacteria are unique organisms with remarkably stable circadian oscillations. These are controlled by a network architecture that comprises two regulatory factors: posttranslational oscillation (PTO) and a transcription/translation feedback loop (TTFL). The clock proteins KaiA, KaiB, and KaiC are essential for the circadian rhythm of the unicellular species Synechococcus elongatus PCC ...
Morton Lindsay M LM NATIONAL INSTITUTES OF - - 2013
In this issue of Blood, Monnereau and colleagues pool 4 retrospective (case-control), observational epidemiologic studies to demonstrate an inverse association between UV radiation (UVR) exposure and risk of developing Hodgkin lymphoma (HL).
Beale Andrew - - 2013
Biological clocks have evolved as an adaptation to life on a rhythmic planet, synchronising physiological processes to the environmental light-dark cycle. Here we examine circadian clock function in Mexican blind cavefish Astyanax mexicanus and its surface counterpart. In the lab, adult surface fish show robust circadian rhythms in per1, which ...
Kumar Dhanananajay - - 2013
Photic phase response curves (PRCs) have been extensively studied in many laboratory-bred diurnal and nocturnal rodents. However, comparatively fewer studies have addressed the effects of photic cues on wild diurnal mammals. Hence, we studied the effects of short durations of light pulses on the circadian systems of the diurnal Indian ...
Lan Weizhong W *MD †PhD Zhongshan Ophthalmic Center (WL), State Key Laboratory of Ophthalmology, Sun Yat-sen University, Guangzhou, China; and Section of Neurobiology of the Eye (WL, MF, FS), Center for Ophthalmology, University of Tuebingen, Tuebingen, - - 2013
Bright light is a potent inhibitor of myopia development in animal models. Because development of refractive errors has been linked to changes in choroidal thickness, we have studied in chickens whether bright light may exert its effects on myopia also through changes in choroidal thickness. Three-day-old chickens were exposed to ...
Lee Chung-Tien - - 2013
The light-oxygen-voltage (LOV) domain protein VIVID (VVD) is a negative regulator of the circadian transcription factor White Collar Complex (WCC) and controls light response and photoadaptation in Neurospora. Blue light converts VIVID from the dark state into the light state (VVDL) with concomitant homodimerization. Upon return to low light conditions ...
Bonmati-Carrion M A - - 2013
The increased prevalence of circadian disruptions due to abnormal coupling between internal and external time makes the detection of circadian phase in humans by ambulatory recordings a compelling need. Here, we propose an accurate practical procedure to estimate circadian phase with the least possible burden for the subject, that is, ...
An Sungwon S Department of Biology, Washington University in St. Louis, Saint Louis, MO - - 2013
Shift work or transmeridian travel can desynchronize the body's circadian rhythms from local light-dark cycles. The mammalian suprachiasmatic nucleus (SCN) generates and entrains daily rhythms in physiology and behavior. Paradoxically, we found that vasoactive intestinal polypeptide (VIP), a neuropeptide implicated in synchrony among SCN cells, can also desynchronize them. The ...
Valentinuzzi Verónica Sandra - - 2013
Triatoma infestans (Reduviidae: Triatominae, "kissing bug") is the main insect vector of Trypanosoma cruzi, the causative agent of Chagas disease, a chronic trypanosomiasis infecting 10 million people world-wide. This hematophagous bug feeds on diurnal and nocturnal species during each host's quiescent time. As the hosts are also its major predators, ...
Kim Seong Jae - - 2013
Age-related changes in circadian rhythms may contribute to the sleep disruption observed in older adults. A reduction of the responsiveness to photic stimuli in the circadian timing system has been hypothesized as a possible reason for the advanced circadian phase in older adults. This project compared the phase shifting response ...
de la Iglesia Horacio O - - 2013
Animals with habitats in the intertidal zone often display biological rhythms that coordinate with both the tidal and the daily environmental cycles. Two recent studies show that the molecular components of the biological clocks mediating tidal rhythms are likely different from the phylogenetically conserved components that mediate circadian (daily) rhythms.
Li Hui - - 2013
We investigated attentional demands in visual rhythm perception of periodically moving stimuli using a visual search paradigm. A dynamic search display consisted of vertically "bouncing dots" with regular rhythms. The search target was defined by a unique visual rhythm (i.e., a shorter or longer period) among rhythmic distractors with identical ...
de Boer Betteco J - - 2013
In the current study, we examined whether coupling influences resulting from unintended afference-based phase entrainment are affected by movement amplitude as such or by the amplitude relation between the limbs. We assessed entrainment strength by studying how passive movements of the contralateral hand influenced unimanual coordination with a metronome. Results ...
Zantke Juliane - - 2013
Life is controlled by multiple rhythms. Although the interaction of the daily (circadian) clock with environmental stimuli, such as light, is well documented, its relationship to endogenous clocks with other periods is little understood. We establish that the marine worm Platynereis dumerilii possesses endogenous circadian and circalunar (monthly) clocks and ...
Zhang Lin - - 2013
Tidal (12.4 hr) cycles of behavior and physiology adapt intertidal organisms to temporally complex coastal environments, yet their underlying mechanism is unknown. However, the very existence of an independent "circatidal" clock has been disputed, and it has been argued that tidal rhythms arise as a submultiple of a circadian clock, operating ...
Hwang Christopher K CK Departments of Ophthalmology and Pharmacology, and Graduate Program in Biochemistry, Cell and Developmental Biology, Emory University School of Medicine, Atlanta, Georgia 30322, Translational Clinical Research Laboratory, Singapore Eye Research Institute, Singapore, Signature Research Program in Neuroscience and Behavioral Disorder, and Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 169712, Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee 37235, and Department of Pharmacology, University of Washington, Seattle, Washington - - 2013
Spatial variation in light intensity, called spatial contrast, comprises much of the visual information perceived by mammals, and the relative ability to detect contrast is referred to as contrast sensitivity (Purves et al., 2012). Recently, retinal dopamine D4 receptors (D4Rs) have been implicated in modulating contrast sensitivity (Jackson et al., ...
Dodd Antony N AN School of Biological Sciences, University of Bristol, Bristol, BS8 1UG, - - 2014
A circadian rhythm matched to the phase and period of the day-night cycle has measurable benefits for land plants. We assessed the contribution of circadian period to the phasing of cellular events with the light : dark cycle. We also investigated the plasticity of circadian period within the Arabidopsis circadian ...
Koldobskiy Dafna - - 2013
Circadian rhythm regulates many physiologic and immunologic processes. Disruption of these processes has been demonstrated in acutely ill, mechanically ventilated patients in the ICU setting. Light has not been studied as an entraining stimulus in the chronically mechanically ventilated patient. The purpose of this study was to determine the association ...
Ramsey David J - - 2013
Abstract Daily changes in the light-dark cycle are the principal environmental signal that enables organisms to synchronize their internal biology with the 24-hour day-night cycle. In humans, the visual system is integral to photoentrainment and is primarily driven by a specialized class of intrinsically photosensitive retinal ganglion cells (ipRGCs) that ...
Sexton Kristian K Thayer School of Engineering at Dartmouth College, Hanover, New Hampshire 03755, USA. - - 2013
Fluorescence guided surgery (FGS) is an emerging technology that has demonstrated improved surgical outcomes. However, dim lighting conditions required by current FGS systems are disruptive to standard surgical workflow. We present a novel FGS system capable of imaging fluorescence under normal room light by using pulsed excitation and gated acquisition. ...
Dubofsky E A EA Department of Biological Sciences, University of New Hampshire, Durham, New Hampshire 03824; - - 2013
Adult American horseshoe crabs, Limulus polyphemus, possess endogenous circadian and circatidal clocks controlling visual sensitivity and locomotion, respectively. The goal of this study was to determine the types of activity rhythms expressed by juvenile horseshoe crabs (n = 24) when exposed to a 14:10 light/dark cycle (LD) for 10 days, ...
Jagannath Aarti A Nuffield Department of Clinical Neurosciences Nuffield Laboratory of Ophthalmology, University of Oxford, Levels 5-6 West Wing, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, - - 2013
Retinal photoreceptors entrain the circadian system to the solar day. This photic resetting involves cAMP response element binding protein (CREB)-mediated upregulation of Per genes within individual cells of the suprachiasmatic nuclei (SCN). Our detailed understanding of this pathway is poor, and it remains unclear why entrainment to a new time ...
Singh Devraj - - 2013
In birds, independent circadian clocks reside in the retina, pineal, and hypothalamus, which interact with each other and produce circadian time at the functional level. However, less is known of the molecular clockwork, and of the integration between central and peripheral clocks in birds. The present study investigated this, by ...
Cao Ruifeng R Department of Biochemistry and Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, - - 2013
Protein synthesis is critical for circadian clock function, but little is known of how translational regulation controls the master pacemaker in mammals, the suprachiasmatic nucleus (SCN). Here we demonstrate that the pivotal translational repressor, the eukaryotic translational initiation factor 4E binding protein 1 (4E-BP1), is rhythmically regulated via the mechanistic target ...
Gyöngyösi Norbert - - 2013
Significance: Both circadian rhythm and the production of reactive oxygen species (ROS) are fundamental features of aerobic eukaryotic cells. The circadian clock enhances the fitness of organisms by enabling them to anticipate cycling changes in the surroundings. ROS generation in the cell is often altered in response to environmental changes, ...
Kantermann Thomas - - 2013
Light and darkness are the main time cues synchronising all biological clocks to the external environment. This little understood evolutionary phenomenon is called circadian entrainment. A new study illuminates our understanding of how modern light- and lifestyles compromise circadian entrainment and impact our biological clocks.
Noser Rahel - - 2013
Efficient space use is a critical challenge for animals relying on stationary resources. It is often difficult with purely observational methods to gain unambiguous insight into any ability of primates to manage and process spatial information. Investigating the visible signs of the decision processes underlying space use often leaves open ...
Hosokawa Norimune N Department of Electrical Engineering and Biological Science, Waseda University, TWIns, 2-2 Wakamatsu-cho, Shinjuku, Tokyo 162-8480, Japan. - - 2013
Circadian rhythms are endogenous biological timing processes that are ubiquitous in organisms ranging from cyanobacteria to humans. In the photoautotrophic unicellular cyanobacterium Synechococcus elongatus PCC 7942, under continuous light (LL) conditions, the transcription-translation feedback loop (TTFL) of KaiC generates a rhythmic change in the accumulation of KaiC relative to KaiA ...
Gu Changgui - - 2013
The suprachiasmatic nucleus (SCN) is a principal circadian clock in mammals, which controls physiological and behavioral daily rhythms. The SCN has two main features: Maintaining a rhythmic cycle of approximately 24 h in the absence of a light-dark cycle (free-running period) and the ability to entrain to external light-dark cycles. ...
Wright Kenneth P KP Jr Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO 80309-0354, USA. - - 2013
The electric light is one of the most important human inventions. Sleep and other daily rhythms in physiology and behavior, however, evolved in the natural light-dark cycle [1], and electrical lighting is thought to have disrupted these rhythms. Yet how much the age of electrical lighting has altered the human ...
Fonken Laura K LK Department of Neuroscience and Institute for Behavioral Medicine Research, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA. - - 2013
With the exception of high latitudes, life has evolved under bright days and dark nights. Most organisms have developed endogenously driven circadian rhythms that are synchronized to this daily light/dark cycle. In recent years, humans have shifted away from the naturally occurring solar light cycle in favor of artificial and ...
Partch Carrie L - - 2013
Circadian clocks coordinate physiology and behavior with the 24h solar day to provide temporal homeostasis with the external environment. The molecular clocks that drive these intrinsic rhythmic changes are based on interlocked transcription/translation feedback loops that integrate with diverse environmental and metabolic stimuli to generate internal 24h timing. In this ...
Fitzgerald James M - - 2013
Delirium is a serious neuropsychiatric syndrome of acute onset that occurs in approximately one in five general hospital patients and is associated with serious adverse outcomes that include loss of adaptive function, persistent cognitive problems and increased mortality. Recent studies indicate a three-domain model for delirium that includes generalised cognitive ...
Niwa Yoshimi Y Center for Gene Research, Graduate School of Science, Nagoya University, Furo, Chikusa, Nagoya 464-8602, - - 2013
Although the circadian clock is a self-sustaining oscillator having a periodicity of nearly 1 d, its period length is not necessarily 24 h. Therefore, daily adjustment of the clock (i.e., resetting) is an essential mechanism for the circadian clock to adapt to daily environmental changes. One of the major cues ...
Stangherlin Alessandra A From the Department of Clinical Neurosciences, University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, National Institute for Health Research (NIHR), Cambridge Biomedical Research Centre, Addenbrooke's Hospital, University of Cambridge, CB2 0QQ Cambridge, United - - 2013
Living organisms possess biological clocks that resonate with environmental cycles in light, temperature, and food availability. Recently, circadian oscillations in the redox state of peroxiredoxin have been described as an additional non-transcriptional timekeeping mechanism. Of note, this redox cycle is conserved in both prokaryotes and eukaryotes. How the classical "transcription-translation ...
Bartok Osnat O Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat-Ram, 91904 Jerusalem, - - 2013
Circadian (24 h) clocks provide a source of internal timing in most living organisms. These clocks keep time by using complex transcriptional/post-translational feedback loops that are strikingly resilient to changes in environmental conditions. In the last few years, interest has increased in the role of post-transcriptional regulation of circadian clock ...
Hut Roelof A RA Chronobiology unit, Centre for Behaviour and Neuroscience, University of Groningen, Groningen, The Netherlands. - - 2013
Properties of the circadian and annual timing systems are expected to vary systematically with latitude on the basis of different annual light and temperature patterns at higher latitudes, creating specific selection pressures. We review literature with respect to latitudinal clines in circadian phenotypes as well as in polymorphisms of circadian ...
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