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Sleep Debt
Sleep debt or sleep deficit is the cumulative effect of not getting enough sleep. A large sleep debt may lead to mental or physical fatigue, and can adversely affect one's mood, energy, and ability to think clearly. There are two kinds of sleep debt: the result of partial sleep deprivation, and of total sleep deprivation. Partial sleep deprivation occurs when a person or a lab animal sleeps too little for several days or weeks. Total sleep deprivation, on the other hand, occurs when the subject is kept awake for at least 24 hours. There is debate in the scientific community over the specifics of sleep debt (see ), and it is not considered to be a disorder. Physiological effects of sleep debt The effects of chronic sleep debt on the human body's metabolic and endocrine processes are significant, particularly for those individuals who are overweight. An analysis of the physiological impacts of sleep debt, published in ''The Lancet'', investigated the physiological effects of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Effects Of Sleep Deprivation
Effect may refer to: * A result or change of something ** List of effects ** Cause and effect, an idiom describing causality Pharmacy and pharmacology * Drug effect, a change resulting from the administration of a drug ** Therapeutic effect, a beneficial change in medical condition, often caused by a drug ** Adverse effect or side effect, an unwanted change in medical condition caused by a drug In media * Special effect, an artificial illusion ** Sound effect, an artificially created or enhanced sound ** Visual effects, artificially created or enhanced images *Audio signal processing ** Effects unit, a device used to manipulate electronic sound *** Effects pedal, a small device attached to an instrument to modify its sound Other uses * Effects, one's personal property or belongings * Effects (G.I. Joe), a fictional character in the G.I. Joe universe * ''Effects'' (film), a 1979 film (give a wide release in 2005) * Effect size, a measure of the strength of a relationship b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ghrelin
Ghrelin (; or lenomorelin, INN) is a hormone primarily produced by enteroendocrine cells of the gastrointestinal tract, especially the stomach, and is often called a "hunger hormone" because it increases the drive to eat. Blood levels of ghrelin are highest before meals when hungry, returning to lower levels after mealtimes. Ghrelin may help prepare for food intake by increasing gastric motility and stimulating the secretion of gastric acid. Ghrelin activates cells in the anterior pituitary gland and hypothalamic arcuate nucleus, including neuropeptide Y neurons that initiate appetite. Ghrelin stimulates brain structures having a specific receptor – the growth hormone secretagogue receptor 1A ( GHSR-1A). Ghrelin also participates in regulation of reward cognition, learning and memory, the sleep-wake cycle, taste sensation, reward behavior, and glucose metabolism. History and name Ghrelin was discovered after the ghrelin receptor (called growth hormone secretag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorylated
In biochemistry, phosphorylation is described as the "transfer of a phosphate group" from a donor to an acceptor. A common phosphorylating agent (phosphate donor) is ATP and a common family of acceptor are alcohols: : This equation can be written in several ways that are nearly equivalent that describe the behaviors of various protonated states of ATP, ADP, and the phosphorylated product. As is clear from the equation, a phosphate group per se is not transferred, but a phosphoryl group (PO3-). Phosphoryl is an electrophile. This process and its inverse, dephosphorylation, are common in biology. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License. Protein phosphorylation often activates (or deactivates) many enzymes. During respiration Phosphorylation is essential to the processes of both anaerobic and aerobic respiration, which involve the production of adenosine triphosphate (ATP), the "high-energy" exchang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alzheimer's Disease
Alzheimer's disease (AD) is a neurodegenerative disease and the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems with language, disorientation (including easily getting lost), mood swings, loss of motivation, self-neglect, and behavioral issues. As a person's condition declines, they often withdraw from family and society. Gradually, bodily functions are lost, ultimately leading to death. Although the speed of progression can vary, the average life expectancy following diagnosis is three to twelve years. The causes of Alzheimer's disease remain poorly understood. There are many environmental and genetic risk factors associated with its development. The strongest genetic risk factor is from an allele of apolipoprotein E. Other risk factors include a history of head injury, clinical depression, and high blood pressure. The progression of the di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amyloid Beta
Amyloid beta (Aβ, Abeta or beta-amyloid) denotes peptides of 36–43 amino acids that are the main component of the amyloid plaques found in the brains of people with Alzheimer's disease. The peptides derive from the amyloid-beta precursor protein (APP), which is cleaved by Beta-secretase 1, beta secretase and gamma secretase to yield Aβ in a cholesterol-dependent process and substrate presentation. Both neurons and oligodendrocytes produce and release Aβ in the brain, contributing to formation of amyloid plaques. Aβ molecules can aggregate to form flexible soluble oligomers which may exist in several forms. It is now believed that certain misfolded oligomers (known as "seeds") can induce other Aβ molecules to also take the misfolded oligomeric form, leading to a chain reaction akin to a prion infection. The oligomers are toxic to nerve cells. The other protein implicated in Alzheimer's disease, tau protein, also forms such prion-like misfolded oligomers, and there is some ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orexin
Orexin (), also known as hypocretin, is a neuropeptide that regulates arousal, wakefulness, and appetite. It exists in the forms of orexin-A and orexin-B. The most common form of narcolepsy, type 1, in which the individual experiences brief losses of muscle tone ("drop attacks" or cataplexy), is caused by a lack of orexin in the brain due to destruction of the cells that produce it.Stanford Center for NarcolepsFAQ(retrieved 27-Mar-2012) There are 50,000–80,000 orexin-producing neurons in the human brain, located predominantly in the perifornical area and lateral hypothalamus. They project widely throughout the central nervous system, regulating wakefulness, feeding, and other behaviours. There are two types of orexin peptide and two types of orexin receptor. Orexin was discovered in 1998 almost simultaneously by two independent groups of researchers working on the rat brain. One group named it orexin, from ''orexis,'' meaning "appetite" in Greek; the other group named it hy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amylase
An amylase () is an enzyme that catalysis, catalyses the hydrolysis of starch (Latin ') into sugars. Amylase is present in the saliva of humans and some other mammals, where it begins the chemical process of digestion. Foods that contain large amounts of starch but little sugar, such as rice and potatoes, may acquire a slightly sweet taste as they are chewed because amylase degrades some of their starch into sugar. The pancreas and salivary gland make amylase (alpha amylase) to hydrolyse dietary starch into disaccharides and trisaccharides which are converted by other enzymes to glucose to supply the body with energy. Plants and some bacteria also produce amylase. Specific amylase proteins are designated by different Greek letters. All amylases are glycoside hydrolases and act on α-1,4-glycosidic bonds. Classification α-Amylase The α-amylases () (CAS registry number, CAS 9014–71–5) (alternative names: 1,4-α-D-glucan glucanohydrolase; glycogenase) are calcium metallop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washington University In St
Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered on Washington, D.C. Washington may also refer to: Places England * Washington Old Hall, ancestral home of the family of George Washington * Washington, Tyne and Wear, a town in the City of Sunderland metropolitan borough * Washington, West Sussex, a village and civil parish Greenland * Cape Washington, Greenland * Washington Land Philippines *New Washington, Aklan, a municipality *Washington, a barangay in Catarman, Northern Samar *Washington, a barangay in Escalante, Negros Occidental *Washington, a barangay in San Jacinto, Masbate *Washington, a barangay in Surigao City United States * Fort Washington (disambiguati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epworth Sleepiness Scale
The Epworth Sleepiness Scale (ESS) is a scale intended to measure daytime sleepiness that is measured by use of a very short questionnaire. This can be helpful in diagnosing sleep disorders. It was introduced in 1991 by Dr Murray Johns of Epworth Hospital in Melbourne, Australia. The questionnaire The questionnaire asks the subject to rate their probability of falling asleep on a scale of increasing probability from 0 to 3 for eight different situations that most people engage in during their daily lives, though not necessarily every day. The scores for the eight questions are added together to obtain a single number. A number in the 0–9 range is considered to be normal while a number in the 10–24 range indicates that expert medical advice should be sought. For instance, scores of 11–15 are shown to indicate the possibility of mild to moderate sleep apnea, where a score of 16 and above indicates the possibility of severe sleep apnea or narcolepsy. Certain questions in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep Onset Latency
In sleep science, sleep onset latency (SOL) is the length of time that it takes to accomplish the transition from full wakefulness to sleep, normally to the lightest of the non-REM sleep stages. Sleep latency studies Pioneering Stanford University sleep researcher William C. Dement reports the early development of the concept, and of the first test for it, the Multiple Sleep Latency Test (MSLT), in his book ''The Promise of Sleep''. Dement and colleagues including Mary Carskadon had been seeking an objective measure of daytime sleepiness to help assess the effects of sleep disorders. In the course of evaluating experimental results, they realized that the amount of time it took to fall asleep in bed was closely linked to the subjects' own self-evaluated level of sleepiness. "This may not seem like an earthshaking epiphany, but conceiving and developing an objective measure of sleepiness was perhaps one of the most important advances in sleep science," Dement and coauthor Chris ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychomotor Vigilance Task
A psychomotor vigilance task (PVT) is a sustained-attention, reaction-timed task that measures the consistency with which subjects respond to a visual stimulus (psychology), stimulus. Research indicates increased sleep debt or sleep deficit correlates with deteriorated alertness, slower problem solving, declined psychomotor learning, psychomotor skills, and increased rate of false positives and false negatives, false responses. Use of PVT tests was championed by David F. Dinges and popularized by its ease of scoring, simple metrics, and convergent validity. However, it was shown that motivation can counteract the detrimental effects of sleep loss for up to 36 hours. How it works The PVT is a simple task where the subject presses a button as soon as the light appears. The light will turn on randomly every few seconds for 5–10 minutes. The main measurement of this task is not to assess the reaction time (mental chronometry), but rather to see how many times the button is not pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
