Daily, weekly and annual patterns in children's accidental sport injuries.

Details of serious injuries to children ≤16 yrs. of age that necessitated urgent surgical intervention by the Department of Pediatric Surgery of the University Hospital of Lausanne, Switzerland were recorded into a database registry. Some 15 110 entries listed the precise time of injury, and 3114 (20.

Circadian time organization of professional firemen: desynchronization-tau differing from 24.0 hours-documented by longitudinal self-assessment of 16 variables.

We investigated the circadian synchronization/desynchronization (by field-study assessment of differences in period, τ, of 16 coexisting and well-documented rhythms) of 30 healthy firemen (FM) exposed to irregular, difficult, and stressful nocturnal work hours who demonstrated excellent clinical tolerance (allochronism). Three groups of FM were studied (A = 12 FM on 24-h duty at the fire station; B = 9 FM on 24-h duty at the emergency call center; C = 9 day-shift administrative FM) of mostly comparable average age, body mass index, career duration, chronotype-morningness/eveningness, and trait of field dependence/independence. The self-assessed 16 circadian rhythms were (i) physiological ones of sleep-wake (sleep log), activity-rest (actography), body temperature (internal transmitter pill probe), right- and left-hand grip strength (hand dynamometer), systolic and diastolic blood pressure (BP) plus heart rate (ambulatory BP monitoring device); (ii) psychological ones (visual analog self-rating scales) of sleepiness, fatigue, fitness for work, and capacity to cope with aggressive social behavior; and (iii) cognitive ones of eye-hand skill and letter cancellation, entailing performance speed (tasks completed/unit time) and accuracy (errors).

Habitual moderate alcohol consumption desynchronizes circadian physiologic rhythms and affects reaction-time performance.

The authors studied longitudinally four healthy young adults to explore if habitual evening intake of a "moderate" amount of wine alters parameters, including period (τ) of circadian rhythms. Subjects, synchronized by diurnal activity from 07.30 h ± 60 min to 23.

24-hour, weekly, and annual patterns in traumatic and non-traumatic surgical pediatric emergencies.

24 h patterns with high frequency components in the incidence of pediatric trauma were validated and quantified in one of our earlier studies. Herein, we further explored the temporal--high frequency, 24 h, weekly (7d), hemi-weekly (3.5d), and annual--patterns in traumatic (1990-1997; n = 15,110 events) and non-traumatic pediatric surgical emergencies (PSE) (1992-2001; n = 5,593 events) as well as automobile accidents (AA) (1990-1997; n = 67,712) in the County of Vaud, Switzerland.

Trauma does not happen at random. Predictable rhythm pattern of injury occurrence in a cohort of 15,110 children.

Background: Several adult chronobiologic studies have shown that accidents do not occur at random. Comparing a large cohort of injured children with uninjured children living in an urban setting, we evaluated the rhythmicity of pediatric injury occurrence.

Methods: A data review of a prospective cohort study of child trauma over an 8-year period was recorded in a Swiss urban setting.

Circadian rhythms in toxic effects of the serotonin antagonist ondansetron in mice.

The aim of the study was to learn whether the lethal and the motor incoordination (ataxia) side effect of ondansetron (Zophren) administration is dosing-time dependent. Ondansetron is a serotonin 5-HT3 receptor antagonist used primarily to control nausea and vomiting arising from cytotoxic chemo- and radiotherapy. A total of 210 male Swiss mice 10 to 12 weeks of age were synchronized for 3 weeks by 12 h light (rest span)/12 h dark (activity span).

Pharmacological blockage of serotonin biosynthesis and circadian changes in oxaliplatin toxicity in rats.

This study investigates if the serotoninergic system plays a role in chronotoxic effects of the anticancer agent oxaliplatin (l-OHP). Four groups of female rats (120 in total) synchronized with light-dark (12 h:12 h) were treated with: (i) saline, (ii) para-chlorophenylalanine (pCPA, an inhibitor of serotonin biosynthesis: 300 mg/kg/d, i.p.

Right- and left-brain hemisphere. Rhythm in reaction time to light signals is task-load-dependent: age, gender, and handgrip strength rhythm comparisons.

In healthy mature subjects simple reaction time (SRT) to a single light signal (an easy task) is associated with a prominent rhythm with tau = 24 h of dominant (DH) as well as nondominant (NDH) hand performance, while three-choice reaction time (CRT), a complex task, is associated with tau = 24 h of the DH but tau < 24 h of the NDH. The aims of the study were to assess the influence of age and gender on the difference in tau of the NDH and DH, as it relates to the corresponding cortical hemisphere of the brain, in comparison to the rhythm in handgrip strength. Healthy subjects, 9 (5 M and 4 F) adolescents 10-16 yr of age and 15 (8 M and 7 F) adults 18-67 yr of age, active between 08:00 +/- 1 h and 23:00 +/- 1:30 h and free of alcohol, tobacco, and drug consumption volunteered.

Accidents in children do not happen at random: predictable time-of-day incidence of childhood trauma.

In a prospective study, 15,110 childhood traumas were recorded by the Pediatric Surgery Service (CHUV, Lausanne) between January 1, 1990 and December 31, 1997. The exact clock hour when the injury occurred and other germane data were obtained. Time series thus obtained were analyzed by several statistical (ANOVA, cosinor, chi2, Table Curve, etc.

Role of school schedule, age, and parental socioeconomic status on sleep duration and sleepiness of Parisian children.

The aim of the study was to assess the duration and quality of sleep of prepubertal (Tanner Scale level 1) physically and mentally healthy children as a function of school schedule (4 versus 4.5 days per week), age and grade (median age of 9.5 years for 4th grade versus median age of 10.

Analysis of circadian and ultradian rhythms of skin surface properties of face and forearm of healthy women.

Biologic rhythms of cells and organisms are well documented and have been extensively studied at the physiologic and molecular levels. For the skin, many circadian changes have been investigated but few systematic studies comparing skin at different body sites have been reported. In this study we investigated facial and forearm skin circadian rhythms in eight healthy Caucasian women.

Serum thymidine kinase levels are elevated and exhibit diurnal variations in patients with advanced ovarian cancer.

Deoxythymidine kinase (TK) is an enzyme involved in DNA synthesis whose serum activity reflects the proliferative activity of tumors and correlates with prognosis in various malignancies. In ovarian cancer, the value of s-TK has not been studied so far. Therefore the serum levels of TK were investigated in patients with advanced ovarian cancer.

Circadian rhythm period in reaction time to light signals: difference between right- and left-hand side.

The study was designed to test the hypothesis that the prominent rhythm period tau of simple reaction time (SRT) and three-choice reaction time (CRT) to light signals may vary between the dominant (DH) and non-dominant (NDH) hand. Eleven healthy subjects, 8 males (16-74 years, including two left-handed) and 3 females (18-43 years), synchronized with a diurnal activity (approximately 07.00 h to approximately 23.

Variability in the period of the blood pressure circadian rhythm in human beings.

In studies and assessments of human beings done in natural settings, it is assumed that the period tau of circadian rhythms, including ones of systolic (SBP) and diastolic (DBP) blood pressure, is equal to 24 hours. To test this hypothesis, SBP and DBP rhythms were studied in 112 medication-free, non-hospitalized subjects (62 males, 47.1 + 2.

Oral contraceptives alter circadian rhythm parameters of cortisol, melatonin, blood pressure, heart rate, skin blood flow, transepidermal water loss, and skin amino acids of healthy young women.

Sixteen healthy women users and nonusers of oral contraceptives (OC) volunteered to document a set of circadian rhythms. Nine were taking OC providing ethynyl estradiol (0.03-0.

Circadian dosing time dependency in the forearm skin penetration of methyl and hexyl nicotinate.

The forearm skin penetration of hydrophilic methyl nicotinate (MN) and lipophilic hexyl nicotinate (HN) was assessed around the clock. The sixteen healthy women (median age: 22 years, weight: 57 kg and height: 162 cm) who volunteered for the study were synchronized with a diurnal activity from 07.00h (+/- 1h) to 23.

Day-night differences in effects of cosmetic treatments on facial skin. Effects on facial skin appearance.

Two groups of 24 healthy caucasian women, similar with regard to age classes (from 19 to 55) as well as fair and dark complexion of skin and hair, volunteered to use during a 14-day span a conventional facial cream (active placebo: AP) and thereafter, during a 21-day span Noctosome (Noctos). The latter is a new generation of liposome made with non-ionic lipids leading to microspheres which include glycopeptides in the aqueous compartment of the vesicle, alpha-tocopherol ester in the membrane-like structure and sphingo-ceramides at the surface of the microspheres. The aim of the study was to test the beneficial effects of Noctos (vsAP) with respectively morning (7-9-hr) and evening (21-23-hr) applications as facial ointments.

Circadian rhythms in circulating T lymphocyte subtypes and plasma testosterone, total and free cortisol in five healthy men.

Circadian variations of circulating T lymphocyte subtypes and their possible relations with those of endogenous cortisol or testosterone were investigated in five healthy young men. Venous blood (40 ml) was obtained every 4 h for 24 h from each subject in January, March, June, August and November. Leucocyte and differential counts were measured.

Circadian time dependence of murine tolerance for the alkylating agent peptichemio.

Since the extent of host toxicity of cytostatics is considerably affected by dosing time, a chronopharmacologic approach was undertaken for optimizing the therapeutic index of the alkylating agent, peptichemio (PTC). In 4 studies involving a total of 463 male B6D2F1 mice, a highly statistically significant circadian rhythm characterized murine tolerance for PTC (8 or 10 mg/kg/day i.v.

Circadian changes in the pharmacokinetics of oral ketoprofen.

Several investigations which have taken treatment time into account have shown that the pharmacokinetic parameters, the therapeutic efficacy and even the toxicity of a large number of products may vary according to the administration schedule. The present study was carried out in order to evaluate any circadian changes in pharmacokinetic parameters of ketoprofen, a new non-steroidal anti-inflammatory drug (NSAID). This randomised crossover study consisted of a single oral dose of ketoprofen 100mg administered to 8 healthy male volunteers, mean age 27.

Circadian and circahemidian rhythms in plasma prolactin of the ram: seasonal changes.

The existence of a circadian rhythm in plasma prolactin of the ram is controversial. Differences among authors can be related to both data sampling (e.g.

Circannual and circa-hemiannual rhythms of basal and stimulated gastric secretion in conscious cats.

Conscious cats equipped with a gastric fistula and a denervated Heidenhain pouch were submitted to weekly measurements of the basal and pentagastrin-stimulated gastric secretion for 1 to 14 years. Rhythms of basal secretion were documented in 37 cats for the group studies, in 25 cats only for the individual studies which required at least whole year data. Twelve-month or 6-month rhythms were detected for each variable studied, i.

Cancer-associated alteration of circadian rhythms in carcinoembryonic antigen (CEA) and alpha-fetoprotein (AFP) in humans.

A circadian rhythm of serum concentrations of two tumor markers (CEA and AFP) was demonstrated in individuals not suffering from cancer. These rhythms exhibited a diurnal peak with a nocturnal dip. They disappeared in cancer groups.