Amanda Pastrick, Matthew Diaz, Griffin Adaya, Victoria Montinola, Madeline Arzbecker, Deborah A M Joye, Jennifer A Evans
Daily rhythms are programmed by a central circadian clock that is modulated by photoperiod. Here, we recorded locomotor activity rhythms in C57Bl/6 or mPer2Luc mice of both sexes held under different housing conditions. First, we confirm that the structure of locomotor activity rhythms differs between male and female mice in both genetic backgrounds. Male mice exhibit a nightly "siesta," whereas female mice fluctuate between nights with and without a nightly siesta, which corresponds with changes in locomotor activity levels, circadian period, and vaginal cytology...
June 6, 2024: Journal of Biological Rhythms
Marie Gombert-Labedens, Elisabet Alzueta, Evelyn Perez-Amparan, Dilara Yuksel, Orsolya Kiss, Massimiliano de Zambotti, Katharine Simon, Jing Zhang, Alessandra Shuster, Allison Morehouse, Andres Alessandro Pena, Sara Mednick, Fiona C Baker
The menstrual cycle is a loop involving the interplay of different organs and hormones, with the capacity to impact numerous physiological processes, including body temperature and heart rate, which in turn display menstrual rhythms. The advent of wearable devices that can continuously track physiological data opens the possibility of using these prolonged time series of skin temperature data to noninvasively detect the temperature variations that occur in ovulatory menstrual cycles. Here, we show that the menstrual skin temperature variation is better represented by a model of oscillation, the cosinor, than by a biphasic square wave model...
May 20, 2024: Journal of Biological Rhythms
Jule Neumann, Dharanish Rajendra, Tobias S Kaiser
Semilunar rhythms are found in numerous marine organisms, but the molecular mechanism and functional principles of endogenous circasemilunar clocks remain elusive. Here, we explore the connection between the free-running circasemilunar clock and the circadian clock in the marine midge Clunio marinus with three different chronobiological assays. First, we found that the free-running circasemilunar period of the adult emergence rhythm in C. marinus changes linearly with diel T-cycle length, supporting a day-counting mechanism...
May 19, 2024: Journal of Biological Rhythms
Chenghao Chen, T Katherine Tamai, Min Xu, Libero Petrone, Paola Oliveri, David Whitmore, Ralf Stanewsky
Cryptochromes (Crys) represent a multi-facetted class of proteins closely associated with circadian clocks. They have been shown to function as photoreceptors but also to fulfill light-independent roles as transcriptional repressors within the negative feedback loop of the circadian clock. In addition, there is evidence for Crys being involved in light-dependent magneto-sensing, and regulation of neuronal activity in insects, adding to the functional diversity of this cryptic protein class. In mammals, Crys are essential components of the circadian clock, but their role in other vertebrates is less clear...
March 28, 2024: Journal of Biological Rhythms
Mary E Harrington, Kurt Bryan, Rob Benedetto, Alec Davidson, Jennifer Evans, Todd Holmes, Stephanie Taylor
No abstract text is available yet for this article.
April 2024: Journal of Biological Rhythms
Avishek Dolai, Severine Soltani, Benjamin Smarr, Amlan Das
The study of chronobiology of foraging behavior in social insects offers valuable models for the investigation of circadian rhythms. We scored hourly nest entries and exits of Oecophylla smaragdina (Asian weaver ant) workers in 9 active non-polydomous nests on days with and without rain and with and without a primarily diurnal predator present. After determining that Oecophylla display a high nest fidelity, we focused exclusively on analyzing nest entry counts: we found a significant decrease in overall entry counts of individual ants on rainy days compared with non-rainy days ( p  < 0...
March 8, 2024: Journal of Biological Rhythms
Cathy A Wyse, Laura M Rudderham, Enya A Nordon, Louise M Ince, Andrew N Coogan, Lorna M Lopez
Molecular timing mechanisms known as circadian clocks drive endogenous 24-h rhythmicity in most physiological functions, including innate and adaptive immunity. Consequently, the response to immune challenge such as vaccination might depend on the time of day of exposure. This study assessed whether the time of day of vaccination (TODV) is associated with the subsequent immune and clinical response by conducting a systematic review of previous studies. The Cochrane Library, PubMed, Google, Medline, and Embase were searched for studies that reported TODV and immune and clinical outcomes, yielding 3114 studies, 23 of which met the inclusion criteria...
March 8, 2024: Journal of Biological Rhythms
Waléria D P Gusmão, Victor M Silva, Annelise M G Paiva, Marco Antonio Mota-Gomes, Wilson Nadruz, Claudia R C Moreno
Augmentation index and pulse wave velocity are markers of vascular compromise and independent predictors of cardiovascular risk and mortality. While the link between shift work and heightened cardiovascular risk is established, the intricate genesis of early cardiovascular outcomes in shift workers remains incompletely understood. However, there is evidence that sleep duration plays a role in this regard. Here we evaluate the association of total sleep time with pulse wave velocity, augmentation index, and central blood pressure in night shift workers...
March 3, 2024: Journal of Biological Rhythms
Anne Landvreugd, René Pool, Michel G Nivard, Meike Bartels
The association between circadian rhythms and diseases has been well established, while the association with mental health is less explored. Given the heritable nature of circadian rhythms, this study aimed to investigate the relationship between genes underlying circadian rhythms and mental health outcomes, as well as a possible gene-environment correlation for circadian rhythms. Polygenic scores (PGSs) represent the genetic predisposition to develop a certain trait or disease. In a sample from the Netherlands Twin Register ( N  = 14,021), PGSs were calculated for two circadian rhythm measures: morningness and relative amplitude (RA)...
March 1, 2024: Journal of Biological Rhythms
Hesham I Farag, Barbara A Murphy, James R Templeman, Charlene Hanlon, Jessica Joshua, Thomas G Koch, Lee Niel, Anna K Shoveller, Gregoy Y Bedecarrats, Amy Ellison, David Wilcockson, Tami A Martino
Circadian biology's impact on human physical health and its role in disease development and progression is widely recognized. The forefront of circadian rhythm research now focuses on translational applications to clinical medicine, aiming to enhance disease diagnosis, prognosis, and treatment responses. However, the field of circadian medicine has predominantly concentrated on human healthcare, neglecting its potential for transformative applications in veterinary medicine, thereby overlooking opportunities to improve non-human animal health and welfare...
February 20, 2024: Journal of Biological Rhythms
Daisuke Ono, David R Weaver, Michael H Hastings, Ken-Ichi Honma, Sato Honma, Rae Silver
It has been 50 years since the suprachiasmatic nucleus (SCN) was first identified as the central circadian clock and 25 years since the last overview of developments in the field was published in the Journal of Biological Rhythms . Here, we explore new mechanisms and concepts that have emerged in the subsequent 25 years. Since 1997, methodological developments, such as luminescent and fluorescent reporter techniques, have revealed intricate relationships between cellular and network-level mechanisms...
February 16, 2024: Journal of Biological Rhythms
Nouneh Boodaghian, Hyunsook Park, Susan E Cohen
Circadian rhythms are found widely throughout nature where cyanobacteria are the simplest organisms, in which the molecular details of the clock have been elucidated. Circadian rhythmicity in cyanobacteria is carried out via the KaiA, KaiB, and KaiC core oscillator proteins that keep ~24 h time. A series of input and output proteins-CikA, SasA, and RpaA-regulate the clock by sensing environmental changes and timing rhythmic activities, including global rhythms of gene expression. Our previous work identified a novel set of KaiC-interacting proteins, some of which are encoded by genes that are essential for viability...
February 15, 2024: Journal of Biological Rhythms
Isabel Schöllhorn, Oliver Stefani, Robert J Lucas, Manuel Spitschan, Christian Epple, Christian Cajochen
The pupil modulates the amount of light that reaches the retina. Not only luminance but also the spectral distribution defines the pupil size. Previous research has identified steady-state pupil size and melatonin attenuation to be predominantly driven by melanopsin, which is expressed by a unique subgroup of intrinsically photosensitive retinal ganglion cells (ipRGCs) that are sensitive to short-wavelength light (~480 nm). Here, we aimed to selectively target the melanopsin system during the evening, while measuring steady-state pupil size and melatonin concentrations under commonly experienced evening light levels (<90 lx)...
February 13, 2024: Journal of Biological Rhythms
Mary E Harrington, Kurt Bryan, Rob Benedetto, Alec Davidson, Jennifer Evans, Todd Holmes, Stephanie Taylor
No abstract text is available yet for this article.
February 10, 2024: Journal of Biological Rhythms
Imran M Usmani, Derk-Jan Dijk, Anne C Skeldon
Accurate assessment of the intrinsic period of the human circadian pacemaker is essential for a quantitative understanding of how our circadian rhythms are synchronized to exposure to natural and man-made light-dark (LD) cycles. The gold standard method for assessing intrinsic period in humans is forced desynchrony (FD) which assumes that the confounding effect of lights-on assessment of intrinsic period is removed by scheduling sleep-wake and associated dim LD cycles to periods outside the range of entrainment of the circadian pacemaker...
February 6, 2024: Journal of Biological Rhythms
Marta Iwanaszko, Nathan Waldeck, Ron Anafi, Amy S Paller, Phyllis C Zee, Anna B Fishbein
Atopic dermatitis (AD) is symptomatically worse in the evening, but the mechanism driving nocturnal eczema remains elusive. Our objective was to determine the circadian rhythm of skin barrier function measured by transepidermal water loss (TEWL) in AD patients and explore the molecular underpinnings. A pilot study was performed on a diverse group of AD ( n  = 4) and control ( n  = 2) young patients. We used an inpatient tightly controlled, modified, constant routine protocol. TEWL was measured at least every 90 min in the antecubital fossa (lesional) and forearm, while whole blood samples were collected every 4 h...
February 2, 2024: Journal of Biological Rhythms
Maria Luísa Jabbur, Chitrang Dani, Kamiel Spoelstra, Antony N Dodd, Carl Hirschie Johnson
Surely most chronobiologists believe circadian clocks are an adaptation of organisms that enhances fitness, but are we certain that this focus of our research effort really confers a fitness advantage? What is the evidence, and how do we evaluate it? What are the best criteria? These questions are the topic of this review. In addition, we will discuss selective pressures that might have led to the historical evolution of circadian systems while considering the intriguing question of whether the ongoing climate change is modulating these selective pressures so that the clock is still evolving...
January 7, 2024: Journal of Biological Rhythms
Chiara Mangini, Lisa Zarantonello, Chiara Formentin, Gianluca Giusti, Esther D Domenie, Domenico Ruggerini, Rodolfo Costa, Debra J Skene, Daniela Basso, Lisa Battagliarin, Antonino Di Bella, Paolo Angeli, Sara Montagnese
The objective of the present study was to test the effects of an inpatient management system (CircadianCare) aimed at limiting the negative impact of hospitalization on sleep by enhancing circadian rhythmicity. Fifty inpatients were randomized to either CircadianCare ( n  = 25; 18 males, 62.4 ± 1.9 years) or standard of care ( n  = 25; 14 males, 64.5 ± 2.3 years). On admission, all underwent a full sleep-wake evaluation; they then completed daily sleep diaries and wore an actigraph for the whole length of hospitalization...
December 28, 2023: Journal of Biological Rhythms
H Craig Heller, Erik Herzog, Allison Brager, Gina Poe, Ravi Allada, Frank Scheer, Mary Carskadon, Horacio O de la Iglesia, Rockelle Jang, Ashley Montero, Kenneth Wright, Philippe Mouraine, Matthew P Walker, Namni Goel, John Hogenesch, Russell N Van Gelder, Lance Kriegsfeld, Cheri Mah, Christopher Colwell, Jamie Zeitzer, Michael Grandner, Chandra L Jackson, J Roxanne Prichard, Steve A Kay, Ketema Paul
Collegiate athletes must satisfy the academic obligations common to all undergraduates, but they have the additional structural and social stressors of extensive practice time, competition schedules, and frequent travel away from their home campus. Clearly such stressors can have negative impacts on both their academic and athletic performances as well as on their health. These concerns are made more acute by recent proposals and decisions to reorganize major collegiate athletic conferences. These rearrangements will require more multi-day travel that interferes with the academic work and personal schedules of athletes...
November 18, 2023: Journal of Biological Rhythms
Elizabeth B Klerman, Mahmoud Affouf, Rebecca Robbins, Jay M Iyer, Cornelia Griggs, Peter T Masiakos, Chana A Sacks
Developing interventions to prevent firearm-related violence and to address its consequences requires an improved understanding of when these violent events are most likely to occur. We explored gunshot events in 6 of the most populated cities in the United States by time of day, day of week, holiday/non-holiday, and month using publicly available datasets. In some of these cities, gunshot events occurred most often at nighttime, on holidays and weekends, and during summer months, with significant interaction effects...
November 18, 2023: Journal of Biological Rhythms
Fetch more papers »
Fetching more papers... Fetching...
Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


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"

We want to hear from doctors like you!

Take a second to answer a survey question.