Background and Objective: Premature ventricular complex (PVC) burden exhibits one of three circadian types, classified as fast-type, slow-type, and independent-type PVC. It is unknown whether PVC circadian types have different heart rate variability (HRV) parameter values. Therefore, this study aimed to evaluate differences in HRV circadian rhythm among fast-, slow-, and independent-type PVC. Methods: This cross-sectional observational study consecutively recruited 65 idiopathic PVC subjects (23 fast-, 20 slow-, and 22 independent-type) as well as five control subjects. Each subject underwent a 24-hour Holter to examine PVC burden and HRV. HRV analysis included components that primarily reflect global, parasympathetic, and sympathetic activities. Repeated measures analysis of variance was used to compare differences in HRV circadian rhythm by PVC type. Results. The average PVC burden was 15.7%, 8.4%, and 13.6% in fast-, slow-, and independent-type idiopathic PVC subjects, respectively. Global, parasympathetic nervous system, and sympathetic nervous system HRV parameters were significantly lower in independenttype PVC versus fast- and slow-type PVC throughout the day and night. Furthermore, we unexpectedly found that tendency towards sympathetic activity dominance during nighttime was only in independent-type PVC. Conclusion The HRV parameters are reduced in patients with independent-type PVC compared to fast- and slowtype PVC. Future research is warranted to determine possible differences in the prognosis between the three PVC types.
Ventricular Premature Complexes ; Circadian Rhythm ; Autonomic Nervous System

Circadian rhythm refers to the daily rhythmic variations in an organism. The irregular lifestyles of modern humans have led to a high incidence of chronic diseases, highlighting an inseparable relationship between disrupted circadian rhythm and disease development. TCM has long discussed rhythmic variations, with records dating back to the Yellow Emperor's Inner Canon(Huang Di Nei Jing), which laid a rich theoretical foundation for the research on circadian rhythm. Modern medical research has provided a more comprehensive explanation of its molecular mechanisms. This article integrated the current understanding of circadian rhythm in both Chinese and western medicine, emphasizing the crucial relationship between rhythm regulation and disease treatment. By highlighting the interdisciplinary nature of the two fields, it offers new directions for exploring the field of chronomedicine.
Humans ; Medicine, Chinese Traditional ; Acupuncture Therapy ; Circadian Rhythm ; Biomedical Research ; Polygonatum

Circadian clock is an internal mechanism evolved to adapt to cyclic environmental changes, especially diurnal changes. Keeping the internal clock in synchronization with the external clock is essential for health. Mismatch of the clocks due to phase shift or disruption of molecular clocks may lead to circadian disorders, including abnormal sleep-wake cycles, as well as disrupted rhythms in hormone secretion, blood pressure, heart rate, body temperature, etc. Long-term circadian disorders are risk factors for various common critical diseases such as metabolic diseases, cardiovascular diseases, and tumor. To prevent or treat the circadian disorders, scientists have conducted extensive research on the function of circadian clocks and their roles in the development of diseases, and screened hundreds of thousands of compounds to find candidates to regulate circadian rhythms. In addition, melatonin, light therapy, exercise therapy, timing and composition of food also play a certain role in relieving associated symptoms. Here, we summarized the progress of both drug- and non-drug-based approaches to prevent and treat circadian clock disorders.
Circadian Rhythm ; Circadian Clocks ; Melatonin/physiology*

Circadian rhythm is an internal regulatory mechanism formed in organisms in response to the circadian periodicity in the environment, which modulates the pathophysiological events, occurrence and development of diseases, and the response to treatment in mammals. It significantly influences the susceptibility, injury, and recovery of ischemic stroke, and the response to therapy. Accumulating evidence indicates that circadian rhythms not only regulate the important physiological factors of ischemic stroke events, such as blood pressure and coagulation-fibrinolysis system, but also participate in the immuno-inflammatory reaction mediated by glial cells and peripheral immune cells after ischemic injury and the regulation of neurovascular unit(NVU). This article aims to link molecular, cellular, and physiological pathways in circadian biology to the clinical consequences of ischemic stroke and to illustrate the impact of circadian rhythms on ischemic stroke pathogenesis, the regulation of NVU, and the immuno-inflammatory responses. The regulation of circadian rhythm by traditional Chinese medicine is reviewed, and the research progress of traditional Chinese medicine intervention in circadian rhythm is summarized to provide a reasonable and valuable reference for the follow-up traditional Chinese medicine research and molecular mechanism research of circadian rhythm.
Animals ; Ischemic Stroke ; Medicine, Chinese Traditional ; Circadian Rhythm ; Blood Coagulation ; Blood Pressure ; Mammals

Circadian rhythm is regulated by circadian clock, which is formed by the body response to external cyclic stimuli through the endogenous circadian clock. Circadian rhythm disturbance is closely related to the risks of a variety of diseases, and its impact on oral health cannot be ignored. Exploring the relationship and related molecular mechanism between circadian rhythm and dental hard tissues development are helpful to deeply understand the pathogenesis of developmental defects on these tissues, which could provide a theoretical basis for prevention and treatment on disorders of dental hard tissues. In order to provide guidance for the disease prevention and treatment, based on the summarization of current research progress, this paper focuses on the involvement of biorhythm in the development of tooth hard tissues as well as the disturbance of circadian rhythm on the formation of enamel and dentin, and analyzes the related regulating mechanism of circadian rhythm and genes during the development of tooth hard tissues.
Circadian Rhythm/genetics* ; Dental Enamel ; Oral Health

The circadian clock is an evolutionary molecular product that is associated with better adaptation to changes in the external environment. Disruption of the circadian rhythm plays a critical role in tumorigenesis of many kinds of cancers, including prostate cancer (PCa). Integrating circadian rhythm into PCa research not only brings a closer understanding of the mechanisms of PCa but also provides new and effective options for the precise treatment of patients with PCa. This review begins with patterns of the circadian clock, highlights the role of the disruption of circadian rhythms in PCa at the epidemiological and molecular levels, and discusses possible new approaches to PCa therapy that target the circadian clock.
Humans ; Male ; Carcinogenesis ; Circadian Clocks/physiology* ; Circadian Rhythm/physiology* ; Prostatic Neoplasms/physiopathology*

Night-shift work may adversely affect health. This study aimed to assess the effect of night-shift work on the level of urinary 6-sulphatoxymelatonin. Repeated measures of urinary 6-sulphatoxymelatonin on the morning before night-shift work and after first, third and fifth night-shift work was undertaken in 29 males, Malay, day-night-shift workers. A total of 29 male workers participated in this study. Median age was 29 years old. The highest level of urinary 6-sulphatoxymelatonin was at time point 1, followed by a significant reduction from time point 1 to time point 2. Subsequently, there was a progressive increase of urinary 6-sulphatoxymelatonin from time point 2 to 4. However, the urinary 6-sulphatoxymelatonin did not normalise at time point 4 and remained lower than the baseline
Circadian Rhythm

Sleep deprivation (SD) has many deleterious health effects and occurs in more than 70% of pregnant women. However, the changes in sex hormones and relevant mechanisms after SD have not been well clarified. The aim of the present study was to explore the effects of SD on the secretion of sex hormones and the underlying mechanisms. Twelve pregnant Wistar rats were divided into control (CON, n = 6) and SD (n = 6) groups. Pregnant rats in the SD group were deprived of sleep for 18 h, and allowed free rest for 6 h, and then the above procedures were repeated until delivery. The CON group lived in a 12 h light/dark light cycle environment. Estradiol (E2) and progesterone (P4) levels were detected by enzyme-linked immunosorbent assay (ELISA), and the expression of circadian clock genes, Bmal1, Clock and Per2, in hypothalamus and pituitary gland tissues were evaluated by immunohistochemistry (IHC) and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The PI3K and Akt phosphorylation levels in the hypothalamic and pituitary tissues were determined by Western blot. The results showed that, compared with the CON group, the SD group exhibited significantly reduced serum E2 and P4 levels, down-regulated Bmal1, Clock and Per2 expression, as well as decreased phosphorylation levels of PI3K and Akt. But there was no significant difference of the total PI3K and Akt protein expression levels between the two groups. These results suggest that SD might affect the expression of the circadian clock genes in the hypothalamus and pituitary via PI3K/Akt pathway, and subsequently regulate the secretion of sex hormones in the pregnant rats, which hints the important roles of SD-induced changes of serum sex hormone levels in the pregnant rats.
ARNTL Transcription Factors/metabolism* ; Animals ; Circadian Clocks/physiology* ; Circadian Rhythm/genetics* ; Female ; Gene Expression Regulation/genetics* ; Gonadal Steroid Hormones/metabolism* ; Hypothalamus/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Pituitary Gland/metabolism* ; Pregnancy ; Progesterone ; Proto-Oncogene Proteins c-akt/metabolism* ; Rats ; Rats, Wistar ; Signal Transduction ; Sleep Deprivation/metabolism*

Difference of chronotypes makes influence to cognitive performance of individuals in routine duties. In this paper, 55 subjects with different chronotypes were subjected to continuous sleep deprivation for 30 h by using the constant routine protocol, during which core body temperature was measured continuously, and subjective sleepiness self-rating and the performance of selective attention were measured hourly. The results showed that the phase difference of core body temperature has no significant difference, yet the amplitude and term difference among the three chronotypes are significant. There was an advance in phase between subjective sleepiness self-rating and core body temperature, and the self-rating sleepiness of evening type came the latest, and the self-rating sleepiness of morning type dissipated the fastest. The response time of selective attention showed a 2 h phase delay with subjective sleepiness self-rating. And the analysis of core body temperature showed that the later the chronotype was, the greater the phase delay was. The correct rate of selective attention of different chronotypes were inconsistent with delay of subjective sleepiness self-rating and core body temperature. We provide reference for industry, aviation, military, medical and other fields to make a more scientific scheduling/ shifting based on cognitive performance characteristics of different chronotypes.
Attention/physiology* ; Circadian Rhythm/physiology* ; Homeostasis ; Humans ; Sleep/physiology* ; Sleep Deprivation ; Sleepiness

The psychological distress of cancer patients seriously affects their therapeutic effects. Effective psychological rehabilitation of cancer patients significantly improves their survival chance and quality of life. Circadian rhythm results from adaptation to the environment during the organism's evolution. When the endogenous clock system is disrupted or the external environment is changed, the body and the environment are out of synchronization, and the circadian rhythm will be disrupted. Circadian rhythm disorder is a common phenomenon in cancer patients, and the changes of circadian rhythm are closely related to their psychological distress. Many studies believe that the circadian rhythm disorder of cancer patients may directly or indirectly affect their psychology through various mechanisms, and targeted intervention by regulating the circadian rhythm of patients may be an essential means to promote the psychological rehabilitation.
Humans ; Quality of Life ; Circadian Rhythm/physiology* ; Chronobiology Disorders ; Neoplasms