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#''Bhojanapurvante'' (before and after lunch) e.g. ''dhatriloha'': a formulation made of ''dhatri'' (Emblica officinalis) and ''loha'' (iron) ''bhasma'' prescribed in ''amlapitta'' (acid peptic disease).  [299]
 
#''Bhojanapurvante'' (before and after lunch) e.g. ''dhatriloha'': a formulation made of ''dhatri'' (Emblica officinalis) and ''loha'' (iron) ''bhasma'' prescribed in ''amlapitta'' (acid peptic disease).  [299]
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The time of drug administration which is related to the type of disease and status of the ''doshas'' in the body can be called as chrono therapeutics. Chronotherapeutics refers to a treatment method in which in vivo drug availability is timed to match rhythms of disease in order to optimize therapeutic outcomes and minimize side effects. It is based on the observation that there is an interdependent relationship between the peak-to-trough rhythmic activity in disease symptoms and risk factors, pharmacologic sensitivity, and pharmacokinetics of many drugs  
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The time of drug administration which is related to the type of disease and status of the ''doshas'' in the body can be called as chronotherapeutics. Chronotherapeutics refers to a treatment method in which in-vivo drug availability is timed to match rhythms of disease in order to optimize therapeutic outcomes and minimize side effects. It is based on the observation that there is an interdependent relationship between the peak-to-trough rhythmic activity in disease symptoms and risk factors, pharmacologic sensitivity, and pharmacokinetics of many drugs.
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The circadian timing system is composed of molecular clocks, which drive 24-h changes in xenobiotic metabolism and detoxification, cell cycle events, DNA repair, apoptosis, and angiogenesis. The cellular circadian clocks are coordinated by endogenous physiological rhythms, so that they tick in synchrony in the host tissues that can be damaged by anticancer agents. As a result, circadian timing can modify 2- to 10-fold the tolerability of anticancer medications in experimental models and in cancer patients. Improved efficacy is also seen when drugs are given near their respective times of best tolerance, due to:
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#Inherently poor circadian entrainment of tumors and
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#Persistent circadian entrainment of healthy tissues.
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The circadian timing system is composed of molecular clocks, which drive 24-h changes in xenobiotic metabolism and detoxification, cell cycle events, DNA repair, apoptosis, and angiogenesis. The cellular circadian clocks are coordinated by endogenous physiological rhythms, so that they tick in synchrony in the host tissues that can be damaged by anticancer agents. As a result, circadian timing can modify 2- to 10-fold the tolerability of anticancer medications in experimental models and in cancer patients. Improved efficacy is also seen when drugs are given near their respective times of best tolerability, due to
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(a) Inherently poor circadian entrainment of tumors and
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(b) Persistent circadian entrainment of healthy tissues.
   
Conversely, host clocks are disrupted whenever anticancer drugs are administered at their most toxic time. On the other hand, circadian disruption accelerates experimental and clinical cancer processes. Gender, circadian physiology, clock genes, and cell cycle critically affect outcome on cancer chronotherapeutics. Mathematical and systems biology approaches currently develop and integrate theoretical, experimental, and technological tools in order to further optimize and personalize the circadian administration of cancer treatments.
 
Conversely, host clocks are disrupted whenever anticancer drugs are administered at their most toxic time. On the other hand, circadian disruption accelerates experimental and clinical cancer processes. Gender, circadian physiology, clock genes, and cell cycle critically affect outcome on cancer chronotherapeutics. Mathematical and systems biology approaches currently develop and integrate theoretical, experimental, and technological tools in order to further optimize and personalize the circadian administration of cancer treatments.
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Many biological functions wax and wane in cycles that repeat each day, month, or year. Such patterns do not reflect simply an organism’s passive response to environmental changes, such as daily cycles of light and darkness. Rather, they reflect the organism’s biological rhythms, that is, its ability to keep track of time and to direct changes in function accordingly. Biological rhythms that repeat approximately every 24 hours are called circadian rhythms (from the Latin circa, for around, and dies,for day)
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Many biological functions wax and wane in cycles that repeat each day, month, or year. Such patterns do not reflect simply an organism’s passive response to environmental changes, such as daily cycles of light and darkness. Rather, they reflect the organism’s biological rhythms, that is, its ability to keep track of time and to direct changes in function accordingly. Biological rhythms that repeat approximately every 24 hours are called circadian rhythms (from the Latin circa, for around, and dies,for day).
 
   
 
   
The frequency of heart attacks peaks between 6 a.m. and noon  asthma attacks are most prevalent at night, human babies are born predominantly in the early morning hours . While these patterns do not necessarily indicate that the events are driven by the circadian pacemaker, they do suggest temporal order in the functioning of the human body.  
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The frequency of heart attacks peaks between 6 a.m. and noon  asthma attacks are most prevalent at night, human babies are born predominantly in the early morning hours. While these patterns do not necessarily indicate that the events are driven by the circadian pacemaker, they do suggest temporal order in the functioning of the human body.  
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This temporal organization appears to be beneficial; the human body is prepared for routine changes in state, such as awakening each morning, rather than simply reacting after shifts in demand In addition, these regular cycles in the body present considerations for diagnosis of health problems and for the timing of medical treatment   
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This temporal organization appears to be beneficial; the human body is prepared for routine changes in state, such as awakening each morning, rather than simply reacting after shifts in demand. In addition, these regular cycles in the body present considerations for diagnosis of health problems and for the timing of medical treatment   
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The circadian rhythms of various functions in humans, such as hormone production, body temperature, and sleepiness, are normally coordinated— i.e., they bear a specific relationship to each other. This temporal organization suggests that some biological timekeeping device must drive, regulate, or at least integrate various circadian rhythms. In mammals, considerable experimental evidence indicates that a region of the brain called the suprachiasmatic nucleus (SCN) is the circadian pacemaker? . The SCN, composed of a cluster of thousands of small nerve cells, is located within a region of the brain, the hypothalamus, that controls such basic functions as food intake and body temperature. [297]
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The circadian rhythms of various functions in humans, such as hormone production, body temperature, and sleepiness, are normally coordinated— i.e., they bear a specific relationship to each other. This temporal organization suggests that some biological timekeeping device must drive, regulate, or at least integrate various circadian rhythms. In mammals, considerable experimental evidence indicates that a region of the brain called the suprachiasmatic nucleus (SCN) is the circadian pacemaker. The SCN, composed of a cluster of thousands of small nerve cells, is located within a region of the brain, the hypothalamus, that controls such basic functions as food intake and body temperature. [297]
    
The secretion of cortisol, a steroid hormone important for metabolism and responses to stress, fluctuates daily, peaking in the very early morning hours and falling to a negligible amount by the end of the day (181). Besides its use as a marker for the internal pacemaker, the circadian rhythm of cortisol secretion may drive other rhythms in the body and has important clinical implications.
 
The secretion of cortisol, a steroid hormone important for metabolism and responses to stress, fluctuates daily, peaking in the very early morning hours and falling to a negligible amount by the end of the day (181). Besides its use as a marker for the internal pacemaker, the circadian rhythm of cortisol secretion may drive other rhythms in the body and has important clinical implications.
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Also, cortisol-like steroid hormones used therapeutically to treat asthma and allergies and to
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Also, cortisol-like steroid hormones used therapeutically to treat asthma and allergies and to suppress the immune system, are best administered in the morning, when they interfere least with the body's own cortisol production. Circadian rhythms in cardiovascular function have long been recognized. Indicators of heart and blood vessel function that demonstrate daily rhythms include blood pressure, heart rate, blood volume and flow, heart muscle function, and responsiveness to hormones (84). The daily fluctuations in cardiovascular function are further illustrated by symptoms of disease. Data have shown that abnormal electrical activity in the heart and chest pains peak at approximately 4 a.m. in patients suffering from coronary heart disease (189,190). As stated earlier, the number of heart attacks has been shown to peak between 6 a.m. and noon (117,140).
suppress the immune system, are best administered in the morning, when they interfere least with the body's own cortisol production. Circadian rhythms in cardiovascular function have long been recognized. Indicators of heart and blood vessel function that demonstrate daily rhythms include blood pressure, heart rate, blood volume and flow, heart muscle function, and responsiveness to hormones (84). The daily fluctuations in cardiovascular function are further illustrated by symptoms of disease. Data have shown that abnormal electrical activity in the heart and chest pains peak at approximately 4 a.m. in patients suffering from coronary heart disease (189,190). As stated earlier, the number of heart attacks has been shown to peak between 6 a.m. and noon (117,140).
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These temporal characteristics of cardiovascular disease indicate the importance of careful timing in their assessment, monitoring, and treatment (120). [299]
 
These temporal characteristics of cardiovascular disease indicate the importance of careful timing in their assessment, monitoring, and treatment (120). [299]
      
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