BACKGROUND Because airway calibre shows a circadian rhythm and since exposure to passive smoking reduced lung function this study was undertaken to investigate whether passive smoking affects the circadian rhythm of peak expiratory flow (PEF) in schoolchildren. METHODS Twenty schoolchildren (12 boys and 8 girls, aged 10-11 years) exposed to passive smoking were matched for sex, age, and heigh...

BACKGROUND Several studies have investigated copeptin as a prognostic marker of different acute diseases and as a diagnostic marker in disorders of water and salt homeostasis. However, no data of the normal circadian rhythm of copeptin in healthy subjects are available. AIM To investigate the circadian rhythm of copeptin in healthy subjects under standardized conditions. METHODS 19 healthy ...

PURPOSE This article reviews the recent advances in understanding of the fundamental properties of circadian rhythms and discusses the clinical features, diagnosis, and treatment of circadian rhythm sleep disorders (CRSDs). RECENT FINDINGS Recent evidence strongly points to the ubiquitous influence of circadian timing in nearly all physiologic functions. Thus, in addition to the prominent sle...

The circadian system shapes the rhythms of most biological functions. The regulation of the cell cycle by a circadian clock was suggested to operate via stages S, G2 and G2/M. This study investigated a possible time link at stages G1 and G1/S as well. The daily expression profiles of cell cycle markers (Ccnd1, Ccne1 and Pcna) and circadian clock genes (Per2 and Clock) were monitored in liver an...

The purpose of this work was to investigate the circadian melatonin system in two tropical teleost species characterised by different behavioural habits, Nile tilapia (diurnal) and African catfish (nocturnal). To do so, fish were subjected to either a control photoperiod (12L:12D), continuous light (LL) or darkness (DD) or a 6L:6D photoperiod. Under 12L:12D, plasma melatonin levels were typical...

A prominent circadian rhythm in the nephrotoxicity of a therapeutic dose of cis-diamminedichloroplatinum (cisplatin) is demonstrated in female Fischer rats. Rats were randomized to receive two doses of either cisplatin or 0.9% NaCl solution 14 days apart at the times of either high or low values in their circadian rhythm of urinary volume. Toxicity was assessed by measuring changes in body weig...