Search our Database of Scientific Publications and Authors

I’m looking for a

    2556 results match your criteria Chronobiology International [Journal]

    1 OF 52

    Do night and around-the-clock firefighters' shift schedules induce deviation in tau from 24 hours of systolic and diastolic blood pressure circadian rhythms?
    Chronobiol Int 2017 Sep 18:1-17. Epub 2017 Sep 18.
    a Unité de Chronobiologie , Fondation A. de Rothschild , Paris cedex, France.
    Systolic (S) and diastolic (D) blood pressures (BP) [SBP and DBP] are circadian rhythmic with period (τ) in healthy persons assumed to be maintained at 24.0h. We tested this assumption in a sample of 30 healthy career (mean >12 yrs) 30-to-46 yr-old male Caucasian French firefighters (FFs) categorized into three groups according to work schedule and duties: Group A - 12 FFs working 12h day, 12h night, and occasionally 24h shifts and whose primary duties are firefighting plus paramedical and road rescue services; Group B - 9 FFs working mostly 12h day and 12h night shifts and whose duties are answering incoming emergency calls and coordinating service vehicle dispatch from fire stations with Group A personnel; Group C - 9 day shift (09:00-17:00h) FFs charged with administrative tasks. Read More

    Effects of differences in the availability of light upon the circadian rhythms of institutionalized elderly.
    Chronobiol Int 2017 Sep 14:1-14. Epub 2017 Sep 14.
    a Laboratori de Neurofisiologia del Son i Ritmes Biològics. Universitat Illes Balears (UIB) , IdISPa , Palma de Mallorca , Spain.
    The aim of this study was to compare the availability of diurnal and nocturnal light in two residences for aged persons (R1 and R2, Palma de Mallorca, Illes Balears, Spain). We found that the R1 inmates were exposed to lower amounts of light during waking time and higher amounts during sleeping time. The main traits of the circadian rhythms and the quality of sleep in the inmates of the two residences were found to be positively related to the availability of light during waking time and negatively to the increased light exposure during bed time. Read More

    Time-of-day effects of exposure to solar radiation on thermoregulation during outdoor exercise in the heat.
    Chronobiol Int 2017 Sep 14:1-15. Epub 2017 Sep 14.
    d Nippon Sport Science University , Tokyo , Japan.
    High solar radiation has been recognised as a contributing factor to exertional heat-related illness in individuals exercising outdoors in the heat. Although solar radiation intensity has been known to have similar time-of-day variation as body temperature, the relationship between fluctuations in solar radiation associated with diurnal change in the angle of sunlight and thermoregulatory responses in individuals exercising outdoors in a hot environment remains largely unknown. The present study therefore investigated the time-of-day effects of variations in solar radiation associated with changing solar elevation angle on thermoregulatory responses during moderate-intensity outdoor exercise in the heat of summer. Read More

    Diurnal opposite variation between angiotensinase activities in photo-neuro-endocrine tissues of rats.
    Chronobiol Int 2017 Sep 14:1-7. Epub 2017 Sep 14.
    a Unit of Physiology, Department of Health Sciences , University of Jaén , Jaén , Spain.
    Central and peripheral renin-angiotensin systems (RASs) act in a coordinated manner for the physiologic functions regulated by neuroendocrine events. However, whereas the diurnal rhythm of peripheral circulatory and tissue RASs is well known, the circadian behaviour of their components in central photo-neuro-endocrine structures, key elements for the control of circadian rhythms, has been barely studied. In the present study, we analysed the aspartyl- (AspAP) and glutamyl-aminopeptidase (GluAP) (aminopeptidase A) activities, the angiotensinases responsible for the metabolism of Ang I to Ang 2-10 and Ang II to Ang III, respectively, in the retina, anterior hypothalamus and pituitary at different light and dark time-points of a 12:12 h light:dark cycle (7-19 h light), using arylamide derivatives as substrates. Read More

    Intra-individual variability in the sleep of senior and junior rugby league athletes during the competitive season.
    Chronobiol Int 2017 Sep 14:1-9. Epub 2017 Sep 14.
    a Performance Sciences Department , Brisbane Broncos Rugby League Club , Red Hill , Queensland , Australia.
    This study examined the sleep intra-individual variability (IIV) of rugby league athletes across senior and junior levels during one week of the competitive season. Forty-five rugby league athletes across elite senior, sub-elite senior and elite junior levels each wore actigraphy monitors for seven days during the competitive season, and completed a subjective sleep diary each morning upon waking. Linear mixed models were used to assess differences in sleep measures between playing levels. Read More

    Effect of monochromatic light on circadian rhythmic expression of clock genes and arylalkylamine N-acetyltransferase in chick retina.
    Chronobiol Int 2017 Sep 14:1-9. Epub 2017 Sep 14.
    a Laboratory of Anatomy of Domestic Animal, College of Animal Medicine , China Agricultural University , Beijing , China.
    Birds have more developed visual function. They not only have the ability to detect light and darkness but also have the color vision. Previous study showed that monochromatic light influenced avian physiological processes, which were controlled by clock genes. Read More

    Seasonal variability of NT-proBNP in Swedish primary care patients.
    Chronobiol Int 2017 Sep 14:1-5. Epub 2017 Sep 14.
    a Department of Medical Sciences , Uppsala University Hospital, Uppsala University , Uppsala , Sweden.
    The aim of this study was to determine if there is a seasonal variation in the widely used heart failure marker NT-proBNP. The study included all primary care requests for NT-proBNP in the county of Uppsala, Sweden, between January 2007 and December 2015. For seasonal variation, the NT-proBNP results for individual months were compared. Read More

    Sleep quality, chronotype and metabolic syndrome components in bipolar disorders during the remission period: Results from the FACE-BD cohort.
    Chronobiol Int 2017 Sep 14:1-11. Epub 2017 Sep 14.
    e Fondation FondaMental, fondation de cooperation scientifique , Créteil , France.
    Data on sleep or circadian abnormalities and metabolic disturbances in euthymic bipolar disorders are scarce and based on small sample sizes. The aim of this study was to explore the associations between sleep disturbances, chronotype and metabolic components in a large sample of euthymic patients with bipolar disorders (BD). From 2009 to 2015, 752 individuals with bipolar disorders from the FACE-BD cohort were included and assessed for sleep quality, chronotype and metabolic components. Read More

    Associations between chronotypes and psychological vulnerability factors of depression.
    Chronobiol Int 2017 Jul 31:1-11. Epub 2017 Jul 31.
    a Department of Clinical Psychology , Institute of Psychology, Leiden University , Leiden , The Netherlands.
    Chronotypes have been associated with psychopathology. The eveningness chronotype has been consistently linked with depressed states or depressive disorder, but the underlying mechanism remains unclear. Prior studies have shown associations between chronotype and personality traits that are linked to depression (e. Read More

    Disrupted circadian rhythms of body temperature, heart rate and fasting blood glucose in prediabetes and type 2 diabetes mellitus.
    Chronobiol Int 2017 Jul 31:1-13. Epub 2017 Jul 31.
    d Institute of Biology/Zoology , Martin Luther University , Halle-Wittenberg , Germany.
    We report a progressive disruption of 24-h rhythms in fasting blood glucose (FBG), body temperature (BT) and heart rate (HR) associated with metabolic dysfunction and the development of prediabetes (PD) and type 2 diabetes mellitus (T2DM) in overweight middle-aged (40-69 years old) humans. Increasing BT and HR mean values and declining 24-h BT and HR amplitudes accompany adverse changes in metabolic state. Increased nocturnal BT and a phase delay of the 24-h BT rhythm, deviant 24-h HR profile and a phase advance of the 24-h HR and FBG rhythms are early signs of the PD metabolic state. Read More

    Effects of altered photoperiod on circadian clock and lipid metabolism in rats.
    Chronobiol Int 2017 Jul 14:1-11. Epub 2017 Jul 14.
    a College of Biotechnology and Bioengineering , Zhejiang University of Technology , Hangzhou , China.
    Disruption of circadian clock timekeeping due to changes in the photoperiod enhances the risk of lipid metabolism disorders and metabolic syndrome. However, the effects of altered photoperiods on the circadian clock and lipid metabolism are not well understood. To explore the effects of altered photoperiods, we developed a rat model where rats were exposed to either short-day or long-day conditions. Read More

    Analysis of MTNR1B gene polymorphisms in relationship with IRS2 gene variants, epicardial fat thickness, glucose homeostasis and cognitive performance in the elderly.
    Chronobiol Int 2017 Jul 14:1-11. Epub 2017 Jul 14.
    a Department of Medical Sciences , Division of Internal Medicine and Chronobiology Unit.
    ABSTARCT Genome-wide association studies pinpointed common variants in or near the MTNR1B gene encoding MT2 melatonin receptor to be strongly associated with fasting glucose levels. IRS2 gene polymorphisms impact insulin resistance and epicardial fat (EF) thickness, which in turn is correlated with visceral adiposity, cognitive ability and risk for metabolic plus cardiovascular disease. We aimed to discover the interactions between MTNR1B and IRS2 gene polymorphisms, insulin sensitivity, EF thickness and cognitive performance in the elderly. Read More

    ARNTL, CLOCK and PER3 polymorphisms - links with chronotype and affective dimensions.
    Chronobiol Int 2017 Jul 14:1-9. Epub 2017 Jul 14.
    b Psychiatric Genetics Unit, Department of Psychiatry , Poznan University of Medical Sciences , Poznan , Poland.
    Recently, seven single nucleotide polymorphisms (SNPs) of ARNTL, TIM and PER3 genes were found associated with affective temperaments in bipolar disorder patients. This study aimed to test whether a) the same associations appear in a non-clinical sample; b) the SNPs are related to other affective dimensions; c) the SNPs underpin the associations between chronotype and affective temperaments/dimensions. Three hundred thirty-eight university students completed the Temperament Scale of Memphis, Pisa, Paris and San Diego Auto-questionnaire, the Centre for Epidemiological Studies Depression Scale, the Perceived Stress Scale, the General Health Questionnaire, the Seasonal Pattern Assessment Questionnaire and the Composite Scale of Morningness. Read More

    Potent synchronization of peripheral circadian clocks by glucocorticoid injections in PER2::LUC-Clock/Clock mice.
    Chronobiol Int 2017 Jul 13:1-16. Epub 2017 Jul 13.
    a Laboratory of Physiology and Pharmacology, School of Advanced Science and Engineering , Waseda University , Shinjuku-ku, Tokyo , Japan.
    In mammals, the central clock (the suprachiasmatic nuclei, SCN) is entrained mainly by the light-dark cycle, whereas peripheral clocks in the peripheral tissues are entrained/synchronized by multiple factors, including feeding patterns and endocrine hormones such as glucocorticoids. Clock-mutant mice (Clock/Clock), which have a mutation in a core clock gene, show potent phase resetting in response to light pulses compared with wild-type (WT) mice, owing to the damped and flexible oscillator in the SCN. However, the phase resetting of the peripheral clocks in Clock/Clock mice has not been elucidated. Read More

    Variation in actigraphy-estimated rest-activity patterns by demographic factors.
    Chronobiol Int 2017 Jun 26:1-15. Epub 2017 Jun 26.
    e Department of Family Medicine & Public Health , University of California, San Diego , San Diego , CA , USA.
    Rest-activity patterns provide an indication of circadian rhythmicity in the free-living setting. We aimed to describe the distributions of rest-activity patterns in a sample of adults and children across demographic variables. A sample of adults (N = 590) and children (N = 58) wore an actigraph on their nondominant wrist for 7 days and nights. Read More

    Visceral adiposity and expression of clock genes in peripheral blood mononuclear cells: A pilot study.
    Chronobiol Int 2017 Jun 26:1-10. Epub 2017 Jun 26.
    c Department of Clinical Nursing , Biobehavioral Research Center, Mo-Im Kim Nursing Research Institute, Yonsei University , Seoul , Korea.
    Increasing evidence suggests a close interrelationship between disrupted circadian rhythms and obesity and metabolic disturbances. In particular, abdominal obesity, which contributes to the pathogenesis of metabolic disease, is associated with disrupted clock gene expression. However, little is known about the relationship between clock gene expression and accurate computed tomography (CT)-based measurements of visceral adiposity. Read More

    Timing of food intake during simulated night shift impacts glucose metabolism: A controlled study.
    Chronobiol Int 2017 Jun 21:1-11. Epub 2017 Jun 21.
    a Centre for Sleep Research , University of South Australia , Adelaide , SA , Australia.
    Eating during the night may increase the risk for obesity and type 2 diabetes in shift workers. This study examined the impact of either eating or not eating a meal at night on glucose metabolism. Participants underwent four nights of simulated night work (SW1-4, 16:00-10:00 h, <50 lux) with a daytime sleep opportunity each day (10:00-16:00 h, <3 lux). Read More

    Importance of sandy bottoms in coral reefs to the oscillation of daily rhythms in the tropical wrasse Halichoeres trimaculatus.
    Chronobiol Int 2017 Jun 16:1-12. Epub 2017 Jun 16.
    a Department of Chemistry, Biology and Marine Science , University of the Ryukyus , Nishihara , Okinawa , Japan.
    Most wrasse species swim during the day and bury themselves in the sandy bottoms of shallow reefs at night. This study aimed to evaluate the importance of sandy bottoms to the day-active/night-inactive rhythmicity of the tropical wrasse Halichoeres trimaculatus. Actogram analysis revealed that fish were active during the photophase and inactive during the scotophase in aquariums with both sandy and bare bottoms. Read More

    Time-of-day variation in sustained attentional control.
    Chronobiol Int 2017 Jun 16:1-9. Epub 2017 Jun 16.
    a Geriatric Research, Education and Clinical Center , Department of Veterans Affairs, Boston Healthcare System , Boston , MA , USA.
    Sustained attention is a fundamental cognitive function underlying many activities in daily life including workplace safety, but its natural variation throughout the day is incompletely characterized. To examine time-of-day variation, we collected a large online data set (N = 6,363) with participation throughout the day and around the world on the gradual-onset continuous performance task, a sensitive measure of sustained attention. This allowed us to examine accuracy, attentional stability, and strategy. Read More

    Light- and clock-control of genes involved in detoxification.
    Chronobiol Int 2017 Jun 15:1-16. Epub 2017 Jun 15.
    a Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling , Stirling , UK.
    Circadian regulation of hepatic detoxification seems to be amongst the key roles of the biological clock. The liver is the major site for biotransformation, and in mammals, it contains several clock-controlled transcription factors such as proline and acidic amino acid-rich basic leucine zipper proteins (PAR bZIP) and basic-helix-loop-helix Per-Arnt-Sim (bHLH-PAS) family that act as circadian regulators of detoxification genes. This investigation explored the existence of daily and circadian expression of transcription factors involved in detoxification, as well as the temporal profile of a set of their target genes in zebrafish liver. Read More

    Neotomodon alstoni mice present sex differences between lean and obese in daily hypothalamic leptin signaling.
    Chronobiol Int 2017 Jun 15:1-11. Epub 2017 Jun 15.
    a Unidad Multidisciplinaria de Docencia e Investigación , Facultad de Ciencias , Juriquilla , Qro México.
    This article compared the effects of spontaneous obesity on the daily profile in the relative amount of the leptin receptor (LepRb), and its output. That is the precursor Pro-opiomelanocortin (POMC) over a 24-hour period and compared with differences in locomotion and food intake in periods of artificial light. Differences between lean and obese mice were examined, as were sex differences. Read More

    Night work, light exposure and melatonin on work days and days off.
    Chronobiol Int 2017 Jun 14:1-14. Epub 2017 Jun 14.
    a Aarhus University Hospital , Department of Occupational Medicine , Aarhus , Denmark.
    We aimed to examine the effects of night work on salivary melatonin concentration during and subsequent to night work and the mediating role of light. We included 254 day workers and 87 night workers who were followed during 322 work days and 301 days off work. Each day was defined as the 24 hour period starting from the beginning of a night shift or from waking in the mornings with day work and days off. Read More

    Early- and late-onset preeclampsia and the DNA methylation of circadian clock and clock-controlled genes in placental and newborn tissues.
    Chronobiol Int 2017 Jun 14:1-12. Epub 2017 Jun 14.
    a Department of Obstetrics and Gynecology , Division of Obstetrics & Prenatal Medicine, Erasmus University Medical Center , Rotterdam , The Netherlands.
    The placenta is important in providing a healthy environment for the fetus and plays a central role in the pathophysiology of preeclampsia (PE). Fetal and placental developments are influenced by epigenetic programming. There is some evidence that PE is controlled to an altered circadian homeostasis. Read More

    The effect of air pollution on diurnal variation of performance in anaerobic tests, cardiovascular and hematological parameters, and blood gases on soccer players following the Yo-Yo Intermittent Recovery Test Level-1.
    Chronobiol Int 2017 Jun 14:1-18. Epub 2017 Jun 14.
    c Research Laboratory ''Sports performance optimization'' National Center of Medicine and Science in Sports (CNMSS) , Tunis , Tunisia.
    This study aimed to investigate the effect of air pollution on diurnal variation of performance in anaerobic tests, cardiovascular and hematological parameters, and blood gases on soccer players following the Yo-Yo Intermittent Recovery Test Level-1 (YYIRT1). In a randomized order, 11 healthy soccer players (mean age: 21.8 [range: 20-24] years; height: 178. Read More

    Chronotype preference matters for depression in youth.
    Chronobiol Int 2017 Jun 14:1-9. Epub 2017 Jun 14.
    a National Taiwan University, Department of Public Health & Institute of Epidemiology and Preventive Medicine , College of Public Health , Taipei , Taiwan.
    Morningness/eveningness (M/E) preference is an important circadian rhythm indicator with strong individual variation. M/E chronotype has been found to be correlated with depression in adults, yet the relationship is less clear in children and adolescents. Additionally, poor sleep quality is another commonly studied risk factor for depression. Read More

    Assessment of sleep in subjects with visual impairment: Comparison using subjective and objective methods.
    Chronobiol Int 2017 Jun 8:1-8. Epub 2017 Jun 8.
    a Center of Physical Activity and Health Research , Santa Catarina State University (UDESC) , Florianópolis , SC , Brazil.
    The objective of the present study was to verify the agreement between objective and subjective measures of sleep in people with and without visual impairment. Thirty-seven subjects with visual impairment participated in the study (19 blind without light perception and 18 low-vision), as well as 34 subjects with normal vision, with paired age and gender characteristics. For the subjective sleep evaluation, we used the Sleep Quality Index-PSQI and for the objective evaluation we used the ActiGraph GT3X+. Read More

    Advanced phases and reduced amplitudes are suggested to characterize the daily rest-activity cycles in depressed adolescent boys.
    Chronobiol Int 2017 Jun 8:1-10. Epub 2017 Jun 8.
    a Department of Public Health Solutions, Mental Health Unit , National Institute for Health and Welfare , Helsinki , Finland.
    Self-reported eveningness has been previously associated with depressed mood among adults and adolescents. Here, we study how circadian indicators based on actigraphic data differ between depressed and healthy adolescent boys. Our sample consisted of 17 medication-free adolescent boys, aged 14. Read More

    Chronotype correlates with developmental index, intelligence and academic achievement: A study based on nationwide indicators.
    Chronobiol Int 2017 Jun 8:1-8. Epub 2017 Jun 8.
    a Department of Biology , University of Tuebingen , Tuebingen , Germany.
    Chronotype or morningness-eveningness (M/E) is an individual trait with a biological basis. In this study, I analysed the relationship between M/E and nationwide available data, such as economic variables, school achievement, intelligence and conscientiousness, which is a personality trait. These variables have been chosen because, first, they are linked on the individual level with circadian preference, and, second these associations have been found based on meta-analyses, which gives these findings a high plausibility. Read More

    Objective working hour characteristics and work-life conflict among hospital employees in the Finnish public sector study.
    Chronobiol Int 2017 Jun 7:1-10. Epub 2017 Jun 7.
    a Work Ability and Work Careers , Finnish Institute of Occupational Health , Helsinki , Finland.
    This epidemiological cohort study, based on Finnish public sector data, investigated the associations between objective working hour characteristics and work-life conflict in day and shift work. The comprehensive data of hospital workers (n = 8 931, 92% women, average age 45 years), consisted of survey responses from 2012, linked with the payroll data of working hour characteristics from 91 days preceding the survey. Logistic regression analysis was used to investigate the associations between working hour characteristics and experiencing work-life conflict often/very often. Read More

    Peat moss Sphagnum riparium follows a circatrigintan growth rhythm in situ: A case report.
    Chronobiol Int 2017 Jun 2:1-4. Epub 2017 Jun 2.
    b Institute of Applied Mathematical Research, Karelian Research Centre, Russian Academy of Sciences , Petrozavodsk , Russia.
    In situ growth of Sphagnum riparium Ångstr. shoots were monitored during the 2015 and 2016 growing seasons in Karelia, Russia. It was established that shoot growth rates fluctuated with a period of around 30 days, that is, showed a circatrigintan rhythm. Read More

    Chronotype and its relationship with sleep disorders in children with attention deficit hyperactivity disorder.
    Chronobiol Int 2017 Jun 2:1-9. Epub 2017 Jun 2.
    c Marmara University Research and Training Hospital , Department of Child and Adolescent Psychiatry , Istanbul , Turkey.
    Chronotype can be classified as morningness types, people who prefer morning hours for their physical and mental activities; eveningness types, people who prefer the afternoon or evening hours; and intermediate types, those who show characteristics of both morningness and eveningness types. Attention deficit hyperactivity disorder (ADHD) has been linked with disturbances in chronotype, particularly increased eveningness. Despite the possibility of an association between chronotypes, sleep disturbances and ADHD symptoms, there is little evidence of this association considering the child population. Read More

    Evening light exposure to computer screens disrupts human sleep, biological rhythms, and attention abilities.
    Chronobiol Int 2017 May 26:1-11. Epub 2017 May 26.
    a The Israeli Center for Interdisciplinary Research in Chronobiology, University of Haifa , Mount Carmel, Haifa , Israel.
    The use of electronic devices with light-emitting screens has increased exponentially in the last decade. As a result, humans are almost continuously exposed to unintentional artificial light. We explored the independent and combined effects of two aspects of screen illumination, light wavelength, and intensity, on sleep, its biological regulation, and related functional outcomes. Read More

    Seasonal and time-of-day variations in acute non-image forming effects of illuminance level on performance, physiology, and subjective well-being.
    Chronobiol Int 2017 May 26:1-18. Epub 2017 May 26.
    a Human-Technology Interaction, School of Innovation Sciences, & Intelligent Lighting Institute , Eindhoven University of Technology , Eindhoven , the Netherlands.
    This study investigated seasonal and time-of-day dependent moderations in the strength and direction of acute diurnal non-image forming (NIF) effects of illuminance level on performance, physiology, and subjective well-being. Even though there are indications for temporal variations in NIF-responsiveness to bright light, scientific insights into potential moderations by season are scarce. We employed a 2 (Light: 165 versus 1700 lx at the eye level, within) × 2 (Season: autumn/winter versus spring, between) × 2 (Time of day: morning versus afternoon, between) mixed-model design. Read More

    Neurotransmitter receptor availability in the rat brain is constant in a 24 hour-period.
    Chronobiol Int 2017 May 26:1-10. Epub 2017 May 26.
    a Institute for Neuroscience and Medicine (INM-2) , Forschungszentrum Jülich , Jülich , Germany.
    Wakefulness and sleep are fundamental characteristics of the brain. We, therefore, hypothesized that transmitter systems contribute to their regulation and will exhibit circadian alterations. We assessed the concentration of various neurotransmitter receptors and transporters including adenosinergic (A1AR, A2AAR, and ENT1), dopaminergic (D1R, D2R, and DAT), and serotonergic (5-HT2AR) target proteins. Read More

    Seasonal pattern in bipolar disorders and cardio-vascular risk factors: A study from the FACE-BD cohort.
    Chronobiol Int 2017 May 24:1-10. Epub 2017 May 24.
    a AP-HP, GH Saint-Louis - Lariboisière - F. Widal , Département de Psychiatrie et de Médecine Addictologique , Paris , France.
    Seasonal pattern (SP) and metabolic syndrome (MetS) are major contributors to poor outcome in bipolar disorders (BD). Patients with seasonal bipolar depression present increased appetite, carbohydrate cravings, weight gain, and hypersomnia, which can increase the development of MetS. MetS also appears to be associated with seasonal mood changes in the general population. Read More

    Association of chronotype and social jetlag with human non-verbal intelligence.
    Chronobiol Int 2017 May 24:1-4. Epub 2017 May 24.
    a Department of Molekular Immunology and Biotechnology, Institute of Physiology, Komi Science Centre , Ural Branch, Russian Academy of Sciences , Syktyvkar , Russia.
    The aim of this study was to evaluate the effects of chronotype and social jetlag (SJL) on intelligence. Subjects were aged 14-25 years (n = 1008). A significant effect of intelligence on academic performance, as measured by the Raven's Standard Progressive Matrices test, was found (F2,917 = 11. Read More

    Factors associated with sleep duration in Brazilian high school students.
    Chronobiol Int 2017 24;34(6):773-781. Epub 2017 May 24.
    b Physical Education Department , Federal University of Santa Catarina (UFSC) , Florianópolis , SC , Brazil.
    The aim of this study was to investigate the factors associated with short sleep duration on southern Brazilian high school students. Our study was comprised of 1,132 adolescents aged 14 to 19 years, enrolled in public high schools in São José, Brazil. The students answered a questionnaire about working (work and workload), health perception, smoking, school schedule, sleep (duration and daytime sleepiness), and socio-demographics data. Read More

    Chronotype distribution in professional rugby players: Evidence for the environment hypothesis?
    Chronobiol Int 2017 12;34(6):762-772. Epub 2017 May 12.
    a Department of Molecular and Cell Biology , Faculty of Science, University of Cape Town , Cape Town , South Africa.
    Individual sport athletes have been shown to comprise unusually high proportions of morning-types (MTs) coupled with a higher prevalence of the morningness-associated PERIOD3 variable number tandem repeat (VNTR) allele, PER3(5). The degree to which type of sport selected is influenced by either chronotype or genotype, or the extent to which sporting environment contributes to chronotype is unclear. The aim of this study was to assess chronotype and PER3 VNTR polymorphism frequencies in team sport players and non-athletic controls. Read More

    Effect of blue-blocking glasses in major depressive disorder with sleep onset insomnia: A randomized, double-blind, placebo-controlled study.
    Chronobiol Int 2017 10;34(6):753-761. Epub 2017 May 10.
    b Department of Psychiatry , Fujita Health University School of Medicine , Toyoake , Aichi , Japan.
    Blue wavelengths form the portion of the visible electromagnetic spectrum that most potently regulates circadian rhythm. We hypothesized that wearing blue-blocking (BB) glasses in the evening may influence circadian rhythm disturbances in patients with major depressive disorder (MDD), resulting in improved sleep and mood. We used a randomized placebo-controlled double-blinded design. Read More

    Differences in morning-evening type and sleep duration between Black and White adults: Results from a propensity-matched UK Biobank sample.
    Chronobiol Int 2017 10;34(6):740-752. Epub 2017 May 10.
    d School of Nursing , University of Pennsylvania , Philadelphia , PA , USA.
    Biological evidence suggests that ethno-racial differences in morning-evening type are possible, whereby Blacks may be more likely to be morning type compared to Whites. However, population-level evidence of ethno-racial difference in morning-evening type is limited. In an earlier study, we reported that morning type was more prevalent in Blacks compared to Whites in the United Kingdom (UK) Biobank cohort (N = 439 933). Read More

    Association of shiftwork and immune cells among police officers from the Buffalo Cardio-Metabolic Occupational Police Stress study.
    Chronobiol Int 2017 10;34(6):721-731. Epub 2017 May 10.
    f Department of Epidemiology and Environmental Health, School of Public Health and Health Professions , University of Buffalo, The State University of New York , Buffalo , New York , USA.
    Shift workers suffer from a constellation of symptoms associated with disruption of circadian rhythms including sleep abnormalities, and abnormal hormone secretion (e.g. melatonin, cortisol). Read More

    Sleep quality, chronotype, temperament and bipolar features as predictors of depressive symptoms among medical students.
    Chronobiol Int 2017 10;34(6):708-720. Epub 2017 May 10.
    a Department of Clinical Pharmacology , Medical University of Lodz , Lodz , Poland.
    The assessment of risk factors is a crucial step in the prevention and treatment of affective disorders and should encompass personal dispositions. The aim of this study was to assess the value of chronotype and temperament as independent predictors of depressive symptoms among medical students. The study surveyed 140 students of the Faculty of Medicine with a battery of questionnaires: the Beck Depression Index (BDI), Hypomania Checklist 32 (HCL-32), Pittsburgh Sleep Quality Index (PSQI), Chronotype Questionnaire and Eysenck Personality Questionnaire Revised. Read More

    Differential effects of circadian typology on sleep-related symptoms, physical fatigue and psychological well-being in relation to resilience.
    Chronobiol Int 2017 27;34(6):677-686. Epub 2017 Apr 27.
    b Department of Neuropsychiatry , Seoul National University Bundang Hospital , Seongnam , Korea.
    Various physiological and psychological functions are influenced by circadian typology (CT), which was reported to be related to resilience. However, few studies have assessed the effects of CT in relation to resilience. The aim of the present study was to assess the influence of CT on sleep-related symptoms, physical fatigue and psychological well-being in relation to resilience. Read More

    Chronobiological factors for compassion satisfaction and fatigue among ambulatory oncology caregivers.
    Chronobiol Int 2017 21;34(6):808-818. Epub 2017 Apr 21.
    a Department of Psychology, Sidney Smith Hall , University of Toronto , Toronto , Ontario , Canada.
    Primary caregivers for victims of chronic illness and or trauma experience both positive and negative emotional consequences. These are broadly classified as compassion satisfaction (CS) and compassion fatigue (CF). Because one of the components of CF, burnout, varies with chronotype and sleep quality, we assessed the influence of chronobiological features on the broader constructs of CS and CF. Read More

    Impact of naturalistic lighting on hospitalized stroke patients in a rehabilitation unit: Design and measurement.
    Chronobiol Int 2017 21;34(6):687-697. Epub 2017 Apr 21.
    a Clinical Stroke Research Unit, Department of Neurology, Faculty of Health Sciences , University of Copenhagen , Rigshospitalet , Glostrup , Denmark.
    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. Read More

    Perinatal light imprinting of circadian clocks and systems (PLICCS): A signature of photoperiod around birth on circadian system stability and association with cancer.
    Chronobiol Int 2017 21;34(6):782-801. Epub 2017 Apr 21.
    a Institute and Policlinic for Occupational Medicine, Environmental Medicine and Prevention Research , University Hospital of Cologne , Cologne , Germany.
    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. The results from these systematic reviews provide supporting evidence of the PLICCS and cancer rationale and highlight that investigations of PLICCS in humans are warranted. Read More

    Melatonin and circadian rhythms in autism: Case report.
    Chronobiol Int 2017 ;34(4):527-530
    a Universidade Estadual Paulista (UNESP) , Marília , Brazil.
    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. Read More

    1 OF 52