keyword
MENU ▼
Read by QxMD icon Read
search

Circadian

keyword
https://www.readbyqxmd.com/read/28430522/impact-of-naturalistic-lighting-on-hospitalized-stroke-patients-in-a-rehabilitation-unit-design-and-measurement
#1
Anders West, Poul Jennum, Sofie Amalie Simonsen, Birgit Sander, Milena Pavlova, Helle K Iversen
INTRODUCTION AND RATIONALE: Stroke is a major cause of acquired cerebral disability among adults, frequently accompanied by depression, anxiety, cognitive impairment, disrupted sleep and fatigue. New ways of intervention to prevent these complications are therefore needed. The major circadian regulator, the suprachiasmatic nucleus, is mainly controlled by natural daylight, and the blue spectrum is considered the most powerful. During stroke rehabilitation, patients typically are mostly indoors and therefore not exposed to the natural daytime variation in light intensity...
April 21, 2017: Chronobiology International
https://www.readbyqxmd.com/read/28430521/perinatal-light-imprinting-of-circadian-clocks-and-systems-pliccs-a-signature-of-photoperiod-around-birth-on-circadian-system-stability-and-association-with-cancer
#2
Philip Lewis, Thomas C Erren
Recent findings from animal models suggest that plasticity of human circadian clocks and systems may be differentially affected by different paradigms of perinatal photoperiod exposure to the detriment of health in later life, including cancer development. Focusing on the example of cancer, we carry out a series of systematic literature reviews concerning perinatal light imprinting of circadian clocks and systems (PLICCS) in animal models, and concerning the risk of cancer development with the primary determinants of the perinatal photoperiod, namely season of birth or latitude of birth...
April 21, 2017: Chronobiology International
https://www.readbyqxmd.com/read/28430154/circadian-rhythm-neuropeptides-in-drosophila-signals-for-normal-circadian-function-and-circadian-neurodegenerative-disease
#3
REVIEW
Qiankun He, Binbin Wu, Jeffrey L Price, Zhangwu Zhao
Circadian rhythm is a ubiquitous phenomenon in many organisms ranging from prokaryotes to eukaryotes. During more than four decades, the intrinsic and exogenous regulations of circadian rhythm have been studied. This review summarizes the core endogenous oscillation in Drosophila and then focuses on the neuropeptides, neurotransmitters and hormones that mediate its outputs and integration in Drosophila and the links between several of these (pigment dispersing factor (PDF) and insulin-like peptides) and neurodegenerative disease...
April 21, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28430105/switching-of-metabolic-programs-in-response-to-light-availability-is-an-essential-function-of-the-cyanobacterial-circadian-output-pathway
#4
Anna M Puszynska, Erin K O'Shea
The transcription factor RpaA is the master regulator of circadian transcription in cyanobacteria, driving genome-wide oscillations in mRNA abundance. Deletion of rpaA has no effect on viability in constant light conditions, but renders cells inviable in cycling conditions when light and dark periods alternate. We investigated the mechanisms underlying this viability defect, and demonstrate that the rpaA(-) strain cannot maintain appropriate energy status at night, does not accumulate carbon reserves during the day, and is defective in transcription of genes crucial for utilization of carbohydrate stores at night...
April 21, 2017: ELife
https://www.readbyqxmd.com/read/28429400/the-circadian-clock-component-lhy-tells-a-plant-when-to-respond-photosynthetically-to-light-in-nature
#5
Youngsung Joo, Variluska Fragoso, Felipe Yon, Ian T Baldwin, Sang-Gyu Kim
The circadian clock is known to increase plant growth and fitness, and thought to prepare plants for photosynthesis at dawn and dusk; whether this happens in nature was unknown. We transformed the native tobacco, Nicotiana attenuata to silence two core clock components, NaLHY (irLHY) and NaTOC1 (irTOC1). We characterized growth and light-and dark-adapted photosynthetic rates (Ac ) throughout a 24 h day in empty vector-transformed (EV), irLHY, and irTOC1 plants in the field, and in NaPhyA-and NaPhyB1-silenced plants in the glasshouse...
April 21, 2017: Journal of Integrative Plant Biology
https://www.readbyqxmd.com/read/28428956/physiological-functions-of-the-cellular-prion-protein
#6
REVIEW
Andrew R Castle, Andrew C Gill
The prion protein, PrP(C), is a small, cell-surface glycoprotein notable primarily for its critical role in pathogenesis of the neurodegenerative disorders known as prion diseases. A hallmark of prion diseases is the conversion of PrP(C) into an abnormally folded isoform, which provides a template for further pathogenic conversion of PrP(C), allowing disease to spread from cell to cell and, in some circumstances, to transfer to a new host. In addition to the putative neurotoxicity caused by the misfolded form(s), loss of normal PrP(C) function could be an integral part of the neurodegenerative processes and, consequently, significant research efforts have been directed toward determining the physiological functions of PrP(C)...
2017: Frontiers in Molecular Biosciences
https://www.readbyqxmd.com/read/28428757/circadian-rhythm-in-kidney-tissue-oxygenation-in-the-rat
#7
Tonja W Emans, Ben J Janssen, Jaap A Joles, C T Paul Krediet
Blood pressure, renal hemodynamics, electrolyte, and water excretion all display diurnal oscillation. Disturbance of these patterns is associated with hypertension and chronic kidney disease. Kidney oxygenation is dependent on oxygen delivery and consumption that in turn are determined by renal hemodynamics and metabolism. We hypothesized that kidney oxygenation also demonstrates 24-h periodicity. Telemetric oxygen-sensitive carbon paste electrodes were implanted in Sprague-Dawley rats (250-300 g), either in renal medulla (n = 9) or cortex (n = 7)...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28428698/circadian-periodicity-of-circulating-plasma-lipid-peroxides-uric-acid-and-ascorbic-acid-in-renal-stone-formers
#8
Rajeev Singh Kushwaha, R C Gupta, J P Sharma, Sumita Sharma, Raj Kumar Singh, Germaine Cornelissen
Circadian periodicity of plasma lipid peroxides and serum ascorbic acid and uric acid levels were studied in one hundred renal stone formers (55 women and 45 men; age 20-60 years) and 50 clinically healthy volunteers (21 women and 29 men; age 21-45 years) with diurnal activity from 06:00 to 22:00 and nocturnal rest. A marked circadian variation was demonstrated by population-mean-cosinor for all studied variables in stone formers and healthy subjects. By comparison to the healthy controls, parameter tests indicate that the stone formers had a higher MESOR (±SE) of MDA (2...
June 2017: Indian Journal of Clinical Biochemistry: IJCB
https://www.readbyqxmd.com/read/28427145/uncoupling-genotoxic-stress-responses-from-circadian-control-increases-susceptibility-to-mammary-carcinogenesis
#9
Mingzhu Fang, Pamela A Ohman Strickland, Hwan-Goo Kang, Helmut Zarbl
We previously demonstrated that chemopreventive methylselenocysteine (MSC) prevents N-Nitroso-N-methylurea (NMU)-induced mammary carcinogenesis in the susceptible Fischer 344 (F344) rats by enhancing NAD+-dependent SIRT1 activity, restoring circadian expression of Period 2 (Per2) and circadian controlled genes. Here, we show that compared to the genetically resistant Copenhagen (COP) rat strain, mammary glands of the F344 rats have a 4-hour phase delay in circadian expression of Per2. Consequently, F344 rats failed to increase SIRT1 activity and circadian expression of Per2 and DDRR genes after exposure to NMU...
February 24, 2017: Oncotarget
https://www.readbyqxmd.com/read/28426765/allatotropin-a-pleiotropic-neuropeptide-that-elicits-mosquito-immune-responses
#10
Salvador Hernández-Martínez, Minerva Sánchez-Zavaleta, Kevin Brito, Antonia Herrera-Ortiz, Sheila Ons, Fernando G Noriega
Allatotropins (AT) are neuropeptides with pleotropic functions on a variety of insect tissues. They affect processes such as juvenile hormone biosynthesis, cardiac rhythm, oviduct and hindgut contractions, nutrient absorption and circadian cycle. The present work provides experimental evidence that AT elicits immune responses in two important mosquito disease vectors, Anopheles albimanus and Aedes aegypti. Hemocytes and an immune-competent mosquito cell line responded to AT by showing strong morphological changes and increasing bacterial phagocytic activity...
2017: PloS One
https://www.readbyqxmd.com/read/28426389/melatonin-and-circadian-rhythms-in-autism-case-report
#11
Gabriela Melloni Zuculo, Bruno S B Gonçalves, Clay Brittes, Luiz Menna-Barreto, Luciana Pinato
Among the most co-occurring conditions in autism spectrum disorders (ASD), there are sleep disorders which may exacerbate associated behavioral disorders and lead to intensification of existing autistic symptoms. Several studies investigating the use of melatonin in the treatment of sleep disorders in ASD have shown comparative efficiency in sleep with little or no side effects. Here we report a case of ASD with non-24-hour rhythm and the effect of melatonin in circadian parameters by actigraphy. Visual analysis of the first 10 days recorded and the periodogram suggest that this patient showed a non-24-hour rhythm...
2017: Chronobiology International
https://www.readbyqxmd.com/read/28426387/characterization-of-bimodal-chronotype-and-its-association-with-sleep-a-population-based-study
#12
Priscila Farias Tempaku, Juliana Ramirez Arruda, Diego Robles Mazzotti, Bruno S B Gonçalves, Mário Pedrazzoli, Lia Bittencourt, Sergio Tufik
The circadian system coordinates internal events in a daily schedule to make sure that the body systems are synchronized to environmental time and internal cues. One important behavioral aspect of the circadian system is the chronotype. It is usually assessed through subjective questionnaires, being the Horne-Ostberg Morningness-Eveningness Questionnaire (MEQ) one of the most used. It classifies individuals into three major categories: morning, evening, and intermediate types. Recently, it has been hypothesized the existence of a fourth chronotype, the bimodal type, through an algorithm derived from the MEQ responses...
2017: Chronobiology International
https://www.readbyqxmd.com/read/28426386/new-zealanders-working-non-standard-hours-also-have-greater-exposure-to-other-workplace-hazards
#13
Sarah M Jay, Philippa H Gander, Amanda Eng, Soo Cheng, Jeroen Douwes, Lis Ellison-Loschmann, Dave McLean, Neil Pearce, Andrea 'tMannetje
Exposure to workplace hazards, such as dust, solvents, and fumes, has the potential to adversely affect the health of people. However, the effects of workplace hazards on health may differ when exposure occurs at different times in the circadian cycle, and among people who work longer hours or who do not obtain adequate sleep. The aim of the present study was to document exposures to workplace hazards across a national sample of New Zealanders, comparing people who work a standard 08:00 -17:00 h Monday-to-Friday working week (Std hours) and those who do not (N-Std hours)...
2017: Chronobiology International
https://www.readbyqxmd.com/read/28425940/circadian-clock-cell-division-and-cancer-from-molecules-to-organism
#14
REVIEW
Anton Shostak
As a response to environmental changes driven by the Earth's axial rotation, most organisms evolved an internal biological timer-the so called circadian clock-which regulates physiology and behavior in a rhythmic fashion. Emerging evidence suggests an intimate interplay between the circadian clock and another fundamental rhythmic process, the cell cycle. However, the precise mechanisms of this connection are not fully understood. Disruption of circadian rhythms has a profound impact on cell division and cancer development and, vice versa, malignant transformation causes disturbances of the circadian clock...
April 20, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28425502/revealing-hidden-conformational-space-of-lov-protein-vivid-through-rigid-residue-scan-simulations
#15
Hongyu Zhou, Brian D Zoltowski, Peng Tao
VIVID(VVD) protein is a Light-Oxygen-Voltage(LOV) domain in circadian clock system. Upon blue light activation, a covalent bond is formed between VVD residue Cys108 and its cofactor flavin adenine dinucleotide(FAD), and prompts VVD switching from Dark state to Light state with significant conformational deviation. However, the mechanism of this local environment initiated global protein conformational change remains elusive. We employed a recently developed computational approach, rigid residue scan(RRS), to systematically probe the impact of the internal degrees of freedom in each amino acid residue of VVD on its overall dynamics by applying rigid body constraint on each residue in molecular dynamics simulations...
April 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28425198/the-cell-adhesion-molecule-epha4-is-involved-in-circadian-clock-functions
#16
Silke Kiessling, Emma K O'Callaghan, Marlène Freyburger, Nicolas Cermakian, Valérie Mongrain
Circadian (~24 h) rhythms of cellular network plasticity in the central circadian clock, the suprachiasmatic nucleus (SCN), have been described. The neuronal network in the SCN regulates photic resetting of the circadian clock as well as stability of the circadian system during both entrained and constant conditions. EphA4, a cell adhesion molecule regulating synaptic plasticity by controlling connections of neurons and astrocytes, is expressed in the SCN. To address whether EphA4 plays a role in circadian photoreception and influences the neuronal network of the SCN, we have analysed circadian wheel-running behavior of EphA4 knockout (EphA4(-/-) ) mice under different light conditions and upon photic resetting, as well as their light-induced protein response in the SCN...
April 20, 2017: Genes, Brain, and Behavior
https://www.readbyqxmd.com/read/28425172/the-homeostatic-and-circadian-sleep-recovery-responses-after-total-sleep-deprivation-in-mice
#17
Garance Dispersyn, Fabien Sauvet, Danielle Gomez-Merino, Sylvain Ciret, Catherine Drogou, Damien Leger, Thierry Gallopin, Mounir Chennaoui
Many studies on sleep deprivation effects lack data regarding the recovery period. We investigated the 2-day homeostatic and circadian sleep recovery response to 24 h of total sleep deprivation (TSD) induced by brief rotation of an activity wheel. Eight mice were implanted with telemetry transmitters (DSI F40-EET) that recorded simultaneously their electroencephalography (EEG), locomotor activity and temperature during 24 h of baseline (BSL), TSD and 2 days of recovery (D1 and D2). In a second experiment, two groups of five non-implanted mice underwent TSD or ad libitum sleep, after which they were killed, adrenal glands were weighed and blood was collected for analysis of corticosterone concentration...
April 20, 2017: Journal of Sleep Research
https://www.readbyqxmd.com/read/28424614/relationship-between-cognitive-and-sleep-wake-variables-in-asymptomatic-offspring-of-patients-with-late-onset-alzheimer-s-disease
#18
Carolina Abulafia, Bárbara Duarte-Abritta, Mirta F Villarreal, María S Ladrón-de-Guevara, Celeste García, Geraldine Sequeyra, Gustavo Sevlever, Leticia Fiorentini, Karl-Jürgen Bär, Deborah R Gustafson, Daniel E Vigo, Salvador M Guinjoan
Early neuropathological changes characteristic of late-onset Alzheimer's disease (LOAD) involve brain stem and limbic structures that regulate neurovegetative functions, including sleep-wake rhythm. Indeed, sleep pattern is an emerging biomarker and a potential pathophysiological mechanism in LOAD. We hypothesized that cognitively asymptomatic, middle-aged offspring of patients with LOAD (O-LOAD) would display a series of circadian rhythm abnormalities prior to the onset of objective cognitive alterations. We tested 31 children of patients with LOAD (O-LOAD) and 19 healthy individuals without family history of Alzheimer's disease (control subjects, CS) with basic tests of cognitive function, as well as actigraphy measures of sleep-wake rhythm, cardiac autonomic function, and bodily temperature...
2017: Frontiers in Aging Neuroscience
https://www.readbyqxmd.com/read/28424270/significance-of-circadian-rhythms-in-severely-brain-injured-patients-a-clue-to-consciousness
#19
Christine Blume, Julia Lechinger, Nayantara Santhi, Renata Del Giudice, Maria-Teresa Gnjezda, Gerald Pichler, Monika Scarpatetti, Johann Donis, Gabriele Michitsch, Manuel Schabus
OBJECTIVE: To investigate the relationship between the presence of a circadian body temperature rhythm and behaviorally assessed consciousness levels in patients with disorders of consciousness (DOC; i.e., vegetative state/unresponsive wakefulness syndrome or minimally conscious state). METHODS: In a cross-sectional study, we investigated the presence of circadian temperature rhythms across 6 to 7 days using external skin temperature sensors in 18 patients with DOC...
April 19, 2017: Neurology
https://www.readbyqxmd.com/read/28423315/mir-132-212-modulates-seasonal-adaptation-and-dendritic-morphology-of-the-central-circadian-clock
#20
Lucia Mendoza-Viveros, Cheng-Kang Chiang, Jonathan L K Ong, Sara Hegazi, Arthur H Cheng, Pascale Bouchard-Cannon, Michael Fana, Christopher Lowden, Peng Zhang, Béatrice Bothorel, Matthew G Michniewicz, Stephen T Magill, Melissa M Holmes, Richard H Goodman, Valérie Simonneaux, Daniel Figeys, Hai-Ying M Cheng
The central circadian pacemaker, the suprachiasmatic nucleus (SCN), encodes day length information by mechanisms that are not well understood. Here, we report that genetic ablation of miR-132/212 alters entrainment to different day lengths and non-24 hr day-night cycles, as well as photoperiodic regulation of Period2 expression in the SCN. SCN neurons from miR-132/212-deficient mice have significantly reduced dendritic spine density, along with altered methyl CpG-binding protein (MeCP2) rhythms. In Syrian hamsters, a model seasonal rodent, day length regulates spine density on SCN neurons in a melatonin-independent manner, as well as expression of miR-132, miR-212, and their direct target, MeCP2...
April 18, 2017: Cell Reports
keyword
keyword
3031
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"