Why and how do we model circadian rhythms?

abstract：:Intertidal species have both circadian and circatidal clocks. Although the behavioral evidence for these oscillators is more than 5 decades old, virtually nothing is known about their molecular clockwork. Pigment-dispersing hormones (PDHs) were originally described in crustaceans. Their insect homologs, pigment-disper...

journal_title：Journal of biological rhythms

authors： Beckwith EJ,Lelito KR,Hsu YW,Medina BM,Shafer O,Ceriani MF,de la Iglesia HO

更新日期：2011-12-01 00:00:00

abstract：:Mice with targeted gene disruption have provided important information about the molecular mechanisms of circadian clock function. A full understanding of the roles of circadian-relevant genes requires manipulation of their expression in a tissue-specific manner, ideally including manipulation with high efficiency wit...

journal_title：Journal of biological rhythms

authors： Weaver DR,van der Vinne V,Giannaris EL,Vajtay TJ,Holloway KL,Anaclet C

更新日期：2018-04-01 00:00:00

abstract：:Although pineal "synaptic" ribbons (SR) are frequently examined by means of quantitative electron microscopy, their functional significance remains unclear. The same is true for related structures--"synaptic" spherules (SPH). In the course of such studies, it has been noted that SR counts may differ from laboratory to...

journal_title：Journal of biological rhythms

authors： Karasek M,Lewinski A,Vollrath L

更新日期：1988-04-01 00:00:00

abstract：:Siberian hamsters are photoperiodic seasonally breeding rodents. To date, there has been no evidence that Siberian hamsters exhibit an annual rhythm in reproductive, thermoregulatory, molt, or body mass changes. However, given that the termination of their winter cycle is under endogenous control, the authors thought ...

journal_title：Journal of biological rhythms

authors： Anchordoquy HC,Lynch GR

更新日期：2000-04-01 00:00:00

abstract：:House sparrows (Passer domesticus) whose circadian rhythms of locomotor activity and feeding had been abolished by pinealectomy were held in constant dim light and periodically exposed to melatonin in the drinking water. By alternating 8 h of melatonin water with variable phases of tap water, rhythms with periods (T) ...

journal_title：Journal of biological rhythms

authors： Heigl S,Gwinner E

更新日期：1995-09-01 00:00:00

abstract：:The authors have shown previously that vasopressin (VP) release from suprachiasmatic nucleus (SCN) efferents in rats is important for the timing of the circadian activity of the hypothalamo-pituitary-adrenal (HPA) axis, resulting in a circadian rise in corticosterone at dusk. When meals are supplied at a fixed time du...

journal_title：Journal of biological rhythms

authors： Kalsbeek A,van Heerikhuize JJ,Wortel J,Buijs RM

更新日期：1998-02-01 00:00:00

abstract：:Many mammalian cell types show daily rhythms in gene expression driven by a circadian pacemaker. For example, cultured astrocytes display circadian rhythms in Period1 and Period2 expression. It is not known, however, how or which intercellular factors synchronize and sustain rhythmicity in astrocytes. Because astrocyt...

journal_title：Journal of biological rhythms

authors： Marpegan L,Krall TJ,Herzog ED

更新日期：2009-04-01 00:00:00

abstract：:Photoperiod influences the distribution of sleep and waking and electroencephalogram (EEG) power density in the Djungarian hamster. In an experimental procedure combining short photoperiod (SP) and low ambient temperature, the light-dark difference in the amount of sleep was decreased, and the changes in slow-wave act...

journal_title：Journal of biological rhythms

authors： Deboer T,Vyazovskiy VV,Tobler I

更新日期：2000-10-01 00:00:00

abstract：:The authors sought to investigate the role of phytochromes A and B (phyA and phyB) and cryptochromes 1 and 2 (cryl and cry2) in the synchronization of the leaf position rhythm in Arabidopsis thaliana. The seedlings were transferred from white light-dark cycles to free-running conditions with or without exposure to a l...

journal_title：Journal of biological rhythms

authors： Yanovsky MJ,Mazzella MA,Whitelam GC,Casal JJ

更新日期：2001-12-01 00:00:00

abstract：:Entrainability of the circadian rhythm of mosquito flight and locomotor activity was investigated by giving a 24-hr temperature cycle (28 degrees C for 16 hr, 23 degrees C for 8 hr) to the free-running rhythm or by shifting the temperature cycle. The phase angle difference between the entrained rhythm and the temperat...

journal_title：Journal of biological rhythms

authors： Chiba Y,Uki M,Kawasaki Y,Matsumoto A,Tomioka K

更新日期：1993-10-01 00:00:00

abstract：:The human circadian timing system has previously been shown to free run with a period slightly longer than 24 h in subjects living in the laboratory under conditions of forced desynchrony. In forced desynchrony, subjects are shielded from bright light and periodic time cues and are required to live on a day length out...

journal_title：Journal of biological rhythms

authors： Kelly TL,Neri DF,Grill JT,Ryman D,Hunt PD,Dijk DJ,Shanahan TL,Czeisler CA

更新日期：1999-06-01 00:00:00

abstract：:Social jetlag represents the discrepancy between circadian and social clocks, which is measured as the difference in hours in midpoint of sleep between work days and free days. Previous studies have shown social jetlag to be associated with body mass index (BMI), glycated hemoglobin levels, heart rate, depressive symp...

journal_title：Journal of biological rhythms

authors： Rutters F,Lemmens SG,Adam TC,Bremmer MA,Elders PJ,Nijpels G,Dekker JM

更新日期：2014-10-01 00:00:00

abstract：:We investigated the extent to which photoperiodic fluctuations synchronize annual thyroid and gonadal rhythmicity in edible dormice. The effects of different daylength manipulations (LD 4:20, LD 6:18, LD 18:6, LD 20:4) were examined during the two critical ascending and regressive phases of the annual plasma testoster...

journal_title：Journal of biological rhythms

authors： Jallageas M,Mas N,Nouguier-Soulé J

更新日期：1991-01-01 00:00:00

abstract：:Subjective well-being largely depends on mood, which shows circadian rhythmicity and can be linked to rhythms in many physiological circadian markers, such as melatonin and cortisol. In healthy young volunteers mood is influenced by an interaction of circadian phase and the duration of time awake. The authors analyzed...

journal_title：Journal of biological rhythms

authors： Birchler-Pedross A,Schröder CM,Münch M,Knoblauch V,Blatter K,Schnitzler-Sack C,Wirz-Justice A,Cajochen C

更新日期：2009-06-01 00:00:00

abstract：:An intricate transcription-translation feedback loop (TTFL) governs cellular circadian rhythms in mammals. Here, we report that the zinc finger transcription factor Krüppel-like factor 9 (KLF9) is regulated by this TTFL, it associates in chromatin at the core circadian clock and clock-output genes, and it acts to modu...

journal_title：Journal of biological rhythms

authors： Knoedler JR,Ávila-Mendoza J,Subramani A,Denver RJ

更新日期：2020-06-01 00:00:00

abstract：:The circadian system in higher organisms temporally orchestrates rhythmic changes in a vast number of genes and gene products in different organs. Complex interactions between these components, both within and among cells, ultimately lead to rhythmic behavior and physiology. Identifying the plethora of circadian targe...

journal_title：Journal of biological rhythms

authors： De Haro L,Panda S

更新日期：2006-12-01 00:00:00

abstract：:The purpose of this study was to determine whether decreased day lengths affect reproduction or the immune system in inbred mice. Irrespective of a nocturnal pineal melatonin rise, the signal for day length information, body and testis weights were the same in various strains 8 weeks after transfer from long to short ...

journal_title：Journal of biological rhythms

authors： Yellon SM,Tran LT

更新日期：2002-02-01 00:00:00

abstract：:The hematologic system performs a number of essential functions, including oxygen transport, the execution of the immune response against tumor cells and invading pathogens, and hemostasis (blood clotting). These roles are performed by erythrocytes (red blood cells), leukocytes (white blood cells), and thrombocytes (p...

journal_title：Journal of biological rhythms

authors： Pritchett D,Reddy AB

更新日期：2015-10-01 00:00:00

abstract：:In Drosophila melanogaster, disruption of night by even short light exposures results in degradation of the clock protein TIMELESS (TIM), leading to shifts in the fly molecular and behavioral rhythms. Several lines of evidence indicate that light entrainment of the brain clock involves the blue-light photoreceptor cry...

journal_title：Journal of biological rhythms

authors： Ivanchenko M,Stanewsky R,Giebultowicz JM

更新日期：2001-06-01 00:00:00

abstract：:Previous research has demonstrated a clear link between late chronotype and depression. The vulnerability factors underpinning this link, however, are unclear. Here the relationship between two specific emotion regulation strategies, cognitive reappraisal and expressive suppression, and chronotype was investigated usi...

journal_title：Journal of biological rhythms

authors： Watts AL,Norbury R

更新日期：2017-08-01 00:00:00

abstract：:The aim of this study was to replicate and extend previous work in which the authors observed lower, shorter, and advanced nocturnal melatonin secretion patterns in premenstrually depressed patients compared to those in healthy control women. The authors also sought to test the hypothesis that the therapeutic effect o...

journal_title：Journal of biological rhythms

authors： Parry BL,Berga SL,Mostofi N,Klauber MR,Resnick A

更新日期：1997-02-01 00:00:00

abstract：:The annual cycle of reproductive function in starlings (Sturnus vulgaris) is driven by seasonal changes in daylength and consists of a 6-month period of photosensitivity, culminating in maximal gonadal development, followed by a 6-month period of photorefractoriness. If male starlings are held under a constant photope...

journal_title：Journal of biological rhythms

authors： Dawson A,McNaughton FJ

更新日期：1993-07-01 00:00:00

abstract：:A 24-h treatment with the cytokine tumor necrosis factor-alpha (TNF-alpha) suppresses transcription of E-box-driven clock genes (D-site albumin promoter binding protein, Dbp; Tyrotroph embryonic factor, Tef ; Hepatic leukemia factor, Hlf; Period homolog to Drosophila 1/2/3, Per1, Per2, and Per3) by yet unknown molecul...

journal_title：Journal of biological rhythms

authors： Petrzilka S,Taraborrelli C,Cavadini G,Fontana A,Birchler T

更新日期：2009-08-01 00:00:00

abstract：:In isolated slices of hypothalamus, suprachiasmatic nucleus (SCN) neurons were recorded intracellularly. Blockade of Ca++ channels increased spike duration, eliminating an early component of the afterhyperpolarization (AHP) that followed evoked spikes. The duration and reversal potential of AHPs were, however, unaffec...

journal_title：Journal of biological rhythms

authors： Thomson AM,West DC

更新日期：1990-04-01 00:00:00

abstract：:Two major approaches have been used to model circadian clocks. Qualitative modeling, used prior to the recent wealth of detailed molecular knowledge, makes general predictions but cannot provide detailed mechanistic insights. The more recent biophysical approach, on the other hand, incorporates the biochemical events ...

journal_title：Journal of biological rhythms

authors： Forger D,Gonze D,Virshup D,Welsh DK

更新日期：2007-06-01 00:00:00

abstract：:Endogenous circadian rhythms are involved in various photoperiodic responses of birds. Investigations involving the mechanisms of photoperiodic time measurement in birds have been confined mainly to temperate zone species using males exclusively. Due to the paucity of experimental evidence on subtropical birds that ha...

journal_title：Journal of biological rhythms

authors： Ravikumar G,Senthilkumaran B,Tewary PD,Goel AK

更新日期：1995-12-01 00:00:00

abstract：:Little is known about the differences in the neural substrates of circadian rhythms that are responsible for the maintenance of differences between diurnal and nocturnal patterns of activity in mammals. In both groups of animals, the suprachiasmatic nucleus (SCN) functions as the principal circadian pacemaker, and sur...

journal_title：Journal of biological rhythms

authors： Nunez AA,Bult A,McElhinny TL,Smale L

更新日期：1999-08-01 00:00:00

abstract：:The mammalian circadian pacemaker is located in the suprachiasmatic nucleus (SCN). Various inputs modulate pacemaker phase, including the serotonergic (5HTergic) input from the midbrain raphe. 5HT phase-advances the SCN pacemaker when applied during mid subjective day. In vitro studies indicate that 5HT advances the m...

journal_title：Journal of biological rhythms

authors： Jovanovska A,Prosser RA

更新日期：2002-04-01 00:00:00

abstract：:In mammals, the suprachiasmatic nucleus (SCN) is the central pacemaker organizing circadian rhythms of behavior and physiology. At the cellular level, the mammalian clock consists of autoregulatory feedback loops involving a set of "clock genes," including the Cryptochrome (Cry) genes, Cry1 and Cry2. Experimental evid...

journal_title：Journal of biological rhythms

authors： Evans JA,Pan H,Liu AC,Welsh DK

更新日期：2012-12-01 00:00:00

abstract：:Various aspects of mammalian endocrine physiology show a time-of-day variation with a period of 24 h, which represents an adaptation to the daily environmental fluctuations resulting from the rotation of the earth. These 24-h rhythms in hormone abundance and consequently hormone function may rely on rhythmic signals p...

journal_title：Journal of biological rhythms

authors： Lin XW,Blum ID,Storch KF

更新日期：2015-08-01 00:00:00