Antidepressants usually require 2–8 weeks after drug administration to obtain a clinical response. In contrast, three fast-acting antidepressant treatments (sleep deprivation, electroconvulsive therapy, and ketamine) significantly reduced depressive symptoms within hours to days in a subgroup of patients with depressive disorder. This review addresses the mechanisms underlying these fast effects, with specific focus on treatment effects on circadian rhythms. Numerous recent studies have shown that circadian dysregulation may play an important role in the pathogenesis of mood disorders. These studies indicate that a common therapeutic mechanism underlying the three fast antidepressant therapies is related to circadian rhythm. Evidence suggests that depressive disorder is associated with circadian rhythm delay and that the mechanism of the antidepressant effect is a process in which the delayed circadian rhythm is restored to normal by the treatment.
Antidepressive Agents ; Chronobiology Disorders ; Circadian Rhythm ; Depression ; Depressive Disorder ; Electroconvulsive Therapy ; Humans ; Ketamine ; Mood Disorders ; Sleep Deprivation

Physiological and behavioral rhythms are governed by an endogenous circadian clock. In this paper are reported the studies on soldier's circadian of melatonin concentrations by means of electricity and light pulses presented to the popliteal region (behind the knee). The results showed that the phase of melatonin concentrations can be regulated by both the electricity pulses and the light pulses. A systematic relation was found between the timing of the electro-stimulating and the magnitude and direction of phase shifts, resulting in the generation of a phase response curve. The phase response curve displayed photic model. These findings have implications for the development of more effective treatments for sleep and circadian rhythm disorders.
Adolescent ; Adult ; Chronobiology Disorders ; prevention & control ; Circadian Rhythm ; physiology ; radiation effects ; Electric Stimulation ; Humans ; Male ; Melatonin ; blood ; physiology ; Military Personnel ; Photic Stimulation ; Sleep Disorders, Circadian Rhythm ; prevention & control

OBJECTIVES: The aim of this study was to evaluate the relationship between shift work and work-related injuries in a representative sample of Korean workers. METHODS: We used data from the Korean Working Condition Survey of 2006. The participants were 7,075 Korean workers 15 to 64 years of age. Logistic regression was employed to estimate the relationship between shift work and work-related injury using the SAS version 9.2 program. RESULTS: Shift work was significantly related to work-related injuries compared to non-shift workers(OR 2.40, 95% CI=1.65~3.48). When personal and occupational risk factors were accounted for, shift work had a statistically meaningful relationship with work-related injuries compared to non-shift work(OR 1.79, 95% CI=1.20~2.66). CONCLUSIONS: In this study, shift workers appear to have a higher risk of work-related injuries compared to non-shift workers. Work-related injuries in shift workers could be attributed to circadian rhythm disorder and sleep problems. Suitable arrangements that ensure flexible working times are needed for shift workers. Further study will be needed to identify and mitigate work-related injuries among shift workers.
Chronobiology Disorders ; Dietary Sucrose ; Humans ; Logistic Models ; Phenothiazines ; Risk Factors

Circadian rhythm is a periodic and continuous change in physiological, behavioral, and mental characteristics that occurs in most organisms on the Earth, because the Earth rotates in a 24-hour cycle. The circadian system regulates daily rhythms of physiology and behavior, such as the sleep/wake cycle, body temperature, hormonal secretion, and mood. The influence of circadian rhythm is very powerful, but limited research has addressed its effects. However, many recent studies have shown that circadian dysregulation may play an important role in the pathogenesis of bipolar disorder. This review study examined current and noteworthy studies, including the authors' own works, and proposes a possible clinical application of bipolar disorder based on evidence that circadian rhythm dysregulation in bipolar disorder may be a key pathogenetic mechanism.
Bipolar Disorder* ; Body Temperature ; Chronobiology Disorders ; Circadian Rhythm* ; Physiology

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

Circadian rhythm disorder is a common society issue caused by jet lag,shift work,sleep disruption and changes in food consumption. Light is the major factor affecting the circadian rhythm system. Disruption of the circadian rhythm system can cause damage to the body,leading to some diseases. Maintaining a normal circadian system is of great importance for good health. Ideal therapeutic effect can not only alleviate symptoms of the diseases,but also recovery the disturbed circadian rhythm to normal. The paper summarizes the modeling methods of animal circadian rhythm disorder,diseases of circadian rhythm abnormality,regulation of circadian clock genes and medicine which are related to circadian rhythm to diseases of circadian rhythm disorder.
Animals ; Circadian Rhythm/genetics* ; Humans ; Jet Lag Syndrome/genetics* ; Sleep ; Sleep Disorders, Circadian Rhythm

The human circadian system is normally synchronised with the solar day, insuring that alertness and performance peak during daytime hours and consolidated sleep occurs during the night. In circadian rhythm sleep disorders, the pattern of sleep-wake is misaligned with the patient's circadian system or the external environment, resulting in insomnia, fatigue, and deterioration in performance. Appropriately-timed exposure to bright light can reset the timing of sleep and wake to the desired times, and improve sleep quality and daytime alertness. The efficacy of bright light therapy, however, is dependent on the time-of-day of the circadian cycle that the light is administered. In this article, we examine the physiological basis for bright light therapy, and we discuss the application of light in the treatment of circadian rhythm sleep disorders including advanced and delayed sleep-phase disorder, free-running disorder (nonentrained type), shiftwork disorder and jet lag disorder. We review the laboratory and field studies which have established bright light therapy as an effective treatment for sleep-wake and circadian misalignment, and we also provide guidelines for the appropriate timing and safe use of bright light therapy.
Chronotherapy ; methods ; Humans ; Jet Lag Syndrome ; therapy ; Phototherapy ; methods ; Sleep Disorders, Circadian Rhythm ; therapy ; Treatment Outcome

Numerous hypotheses have been put forth over the years to explain the development of bipolar disorder. Of these, circadian rhythm hypotheses have gained much importance of late. While the hypothalamus-pituitary-adrenal (HPA) axis hyperactivation hypothesis and the monoamine hypothesis somewhat explain the pathogenic mechanism of depression, they do not provide an explanation for the development of mania/hypomania. Interestingly, all patients with bipolar disorder display significant disruption of circadian rhythms and sleep/wake cycles throughout their mood cycles. Indeed, mice carrying the Clock gene mutation exhibit an overall behavioral profile that is similar to human mania, including hyperactivity, decreased sleep, lowered depression-like behavior, and lower anxiety. It was recently reported that monoamine signaling is in fact regulated by the circadian system. Thus, circadian rhythm instability, imposed on the dysregulation of HPA axis and monoamine system, may in turn increase individual susceptibility for switching from depression to mania/hypomania. In addition to addressing the pathophysiologic mechanism underlying the manic switch, circadian rhythm hypotheses can explain other bipolar disorder-related phenomena such as treatment resistant depression and mixed features.
Animals ; Bipolar Disorder* ; Chronobiology Disorders ; Circadian Rhythm* ; Depression ; Depressive Disorder, Treatment-Resistant ; Humans ; Mice

Like functions of other organisms, most of the physiological and behavioral functions of human are characterized by day-night rhythms. The rhythms which exhibit approximately 24-hour periodicity are called as circadian rhythms. This review is to summarize the progress of studies on relation of circadian rhythum disruption and cancer. The research results from animal experiments and population-based epidemiological studies have showed that cancer is closly related to circadian rhythm. Although numrous studies have demonstrated the close relation between circadian rhythm disruption and cancer, the mechanism is not yet clear. The current studies attributed decreased level of melatonin secretion and disruption of clock genes expression to the mechanism of carcinogenesis of circadian rhythm disruption.
Animals ; Chronobiology Disorders ; physiopathology ; Humans ; Neoplasms ; epidemiology ; physiopathology ; Risk Factors ; United States ; epidemiology

Hypertension plays an important role in the pathogenesis of stroke,which,however,is only known at the blood pressure level.The relationship between circadian rhythm of blood pressure(especially the circadian rhythm disorder of blood pressure)and stroke has been a hot research topic.This article reviews the concept of circadian rhythm of blood pressure,classification of circadian rhythm disorder of blood pressure,and the relationship of circadian rhythm disorder of blood pressure with ischemic stroke.
Blood Pressure ; Brain Ischemia/complications* ; Chronobiology Disorders/complications* ; Circadian Rhythm ; Humans ; Hypertension/complications* ; Ischemic Stroke/complications*