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Hormesis
Hormesis is a characteristic of many biological processes, namely a biphasic or triphasic response to exposure to increasing amounts of a substance or condition. Within the hormetic zone, the biological response to low exposures to toxins and other stressors is generally favorable. The term "hormesis" comes from Greek ''hórmēsis'' "rapid motion, eagerness", itself from ancient Greek ''hormáein'' "to set in motion, impel, urge on", the same Greek root as the word ''hormone''. The term 'hormetics' has been proposed for the study and science of hormesis. In toxicology, hormesis is a dose response phenomenon to xenobiotics or other stressors characterized by a low-dose stimulation, with zero dose and high-dose inhibition, thus resulting in a J-shaped or an inverted U-shaped dose response (e.g. the arms of the "U" are inhibitory or toxic concentrations whereas the curve region stimulates a beneficial response.) Generally speaking, hormesis pertains to the study of benefits of exposur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hormesis Dose Response Graph
Hormesis is a characteristic of many biological processes, namely a biphasic or triphasic response to exposure to increasing amounts of a substance or condition. Within the hormetic zone, the biological response to low exposures to toxins and other stressors is generally favorable. The term "hormesis" comes from Greek ''hórmēsis'' "rapid motion, eagerness", itself from ancient Greek ''hormáein'' "to set in motion, impel, urge on", the same Greek root as the word ''hormone''. The term 'hormetics' has been proposed for the study and science of hormesis. In toxicology, hormesis is a dose response phenomenon to xenobiotics or other stressors characterized by a low-dose stimulation, with zero dose and high-dose inhibition, thus resulting in a J-shaped or an inverted U-shaped dose response (e.g. the arms of the "U" are inhibitory or toxic concentrations whereas the curve region stimulates a beneficial response.) Generally speaking, hormesis pertains to the study of benefits of exposu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homeopathy
Homeopathy or homoeopathy is a pseudoscientific system of alternative medicine. It was conceived in 1796 by the German physician Samuel Hahnemann. Its practitioners, called homeopaths, believe that a substance that causes symptoms of a disease in healthy people can cure similar symptoms in sick people; this doctrine is called '' similia similibus curentur'', or "like cures like". Homeopathic preparations are termed ''remedies'' and are made using homeopathic dilution. In this process, the selected substance is repeatedly diluted until the final product is chemically indistinguishable from the diluent. Often not even a single molecule of the original substance can be expected to remain in the product. Between each dilution homeopaths may hit and/or shake the product, claiming this makes the diluent remember the original substance after its removal. Practitioners claim that such preparations, upon oral intake, can treat or cure disease. All relevant scientific knowledge a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Dose Makes The Poison
"The dose makes the poison" ( la, dosis sola facit venenum 'only the dose makes the poison') is an adage intended to indicate a basic principle of toxicology. It is credited to Paracelsus who expressed the classic toxicology maxim "All things are poison, and nothing is without poison; the dosage alone makes it so a thing is not a poison." This is often condensed to: "The dose makes the poison" or in Latin, . It means that a substance can produce the harmful effect associated with its toxic properties only if it reaches a susceptible biological system within the body in a high enough concentration (i.e., dose). The principle relies on the finding that all chemicals—even water and oxygen—can be toxic if too much is eaten, drunk, or absorbed. "The toxicity of any particular chemical depends on many factors, including the extent to which it enters an individual’s body." [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mithridatism
Mithridatism is the practice of protecting oneself against a poison by gradually self-administering non-lethal amounts. The word is derived from Mithridates VI, the King of Pontus, who so feared being poisoned that he regularly ingested small doses, aiming to develop immunity. Background Mithridates VI's father, Mithridates V, was assassinated by poisoning by a conspiracy among his attendants. After this, Mithridates VI's mother held regency over Pontus (a Hellenistic kingdom, 281 BC–62 AD) until a male heir came of age. Mithridates was in competition with his brother for the throne and his mother began to favor his brother. Supposedly, during his youth, he began to suspect plots against him at his own mother's orders and was aware of her possible connection with his father's death. He then began to notice pains in his stomach during his meals and suspected his mother had ordered small amounts of poison to be added to his food to slowly kill him off. With other assassination ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Therapeutic Window
The therapeutic index (TI; also referred to as therapeutic ratio) is a quantitative measurement of the relative safety of a drug. It is a comparison of the amount of a therapeutic agent that causes the therapeutic effect to the amount that causes toxicity. The related terms therapeutic window or safety window refer to a range of doses which optimize between efficacy and toxicity, achieving the greatest therapeutic benefit without resulting in unacceptable side-effects or toxicity. Classically, in an established clinical indication setting of an approved drug, TI refers to the ratio of the dose of drug that causes adverse effects at an incidence/severity not compatible with the targeted indication (e.g. toxic dose in 50% of subjects, TD) to the dose that leads to the desired pharmacological effect (e.g. efficacious dose in 50% of subjects, ED). In contrast, in a drug development setting TI is calculated based on plasma exposure levels. In the early days of pharmaceutical toxico ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dose–response Relationship
The dose–response relationship, or exposure–response relationship, describes the magnitude of the response of an organism, as a function of exposure (or doses) to a stimulus or stressor (usually a chemical) after a certain exposure time. Dose–response relationships can be described by dose–response curves. This is explained further in the following sections. A stimulus response function or stimulus response curve is defined more broadly as the response from any type of stimulus, not limited to chemicals. Motivation for studying dose–response relationships Studying dose response, and developing dose–response models, is central to determining "safe", "hazardous" and (where relevant) beneficial levels and dosages for drugs, pollutants, foods, and other substances to which humans or other organisms are exposed. These conclusions are often the basis for public policy. The U.S. Environmental Protection Agency has developed extensive guidance and reports on dose–re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenobiotic
A xenobiotic is a chemical substance found within an organism that is not naturally produced or expected to be present within the organism. It can also cover substances that are present in much higher concentrations than are usual. Natural compounds can also become xenobiotics if they are taken up by another organism, such as the uptake of natural human hormones by fish found downstream of sewage treatment plant outfalls, or the chemical defenses produced by some organisms as protection against predators. The term xenobiotics, however, is very often used in the context of pollutants such as dioxins and polychlorinated biphenyls and their effect on the biota, because xenobiotics are understood as substances foreign to an entire biological system, i.e. artificial substances, which did not exist in nature before their synthesis by humans. The term xenobiotic is derived from the Greek words ξένος (xenos) = foreigner, stranger and βίος (bios) = life, plus the Greek suffix ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electuaries
An electuary is a medicine consisting of a powder or other ingredient mixed with something sweet such as honey to make it more palatable."The Doctor and the Buccaneer: Sir Hans Sloane's Case History of Sir Henry Morgan, Jamaica, 1688" by Richard B. Sheridan, '' Journal of the History of Medicine and Allied Sciences
The ''Journal of the History of Medicine and Allied Sciences'' is a quarterly peer-reviewed academic journal that was originally published by the Department of the History of Medicine at Yale University and now is continued by Oxford Unive ...
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Edward Calabrese
Edward J. Calabrese is an American toxicologist and professor in the department of environmental health sciences at the University of Massachusetts Amherst. He is the editor emeritus of the scientific journal '' Dose-Response''. Education Calabrese grew up in Bridgewater, Massachusetts. He received his B.S. from Bridgewater State College in 1968 and his M.A. and Ph.D. from the University of Massachusetts Amherst in 1972 and 1973, respectively. Academic career Calabrese began working at the University of Massachusetts Amherst in 1976. Research Early in his career, Calabrese conducted research on carcinogens. However, he is best known for his research into, and championing of, hormesis Hormesis is a characteristic of many biological processes, namely a biphasic or triphasic response to exposure to increasing amounts of a substance or condition. Within the hormetic zone, the biological response to low exposures to toxins and othe ..., which he has called "the fundamental dose-respons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chester M
Chester is a cathedral city and the county town of Cheshire, England. It is located on the River Dee, close to the English–Welsh border. With a population of 79,645 in 2011,"2011 Census results: People and Population Profile: Chester Locality"; downloaded froCheshire West and Chester: Population Profiles, 17 May 2019 it is the most populous settlement of Cheshire West and Chester (a unitary authority which had a population of 329,608 in 2011) and serves as its administrative headquarters. It is also the historic county town of Cheshire and the second-largest settlement in Cheshire after Warrington. Chester was founded in 79 AD as a "castrum" or Roman fort with the name Deva Victrix during the reign of Emperor Vespasian. One of the main army camps in Roman Britain, Deva later became a major civilian settlement. In 689, King Æthelred of Mercia founded the Minster Church of West Mercia, which later became Chester's first cathedral, and the Angles extended and strengthened t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rudolph Arndt
Rudolf Gottfried Arndt (31 March 1835 – 29 January 1900) was a German psychiatrist from Bialken, district of Marienwerder. Biography Arndt studied in Greifswald and Halle. As a student, his instructors included Felix von Niemeyer (1820–1871), Heinrich Adolf von Bardeleben (1819–1895), and Heinrich Philipp August Damerow (1798–1866). He was conferred doctor of medicine on 20 February 1860. From 1861 he maintained a private practice, and also participated in the Second Schleswig War (1864), Austro-Prussian War (1866) and Franco-Prussian War (1870–71). In 1867 he obtained his habilitation, subsequently serving as director of the ''Irren-Heil- und Pflege-Anstalt'' in Greifswald. In 1873 he became an associate professor of psychiatry at Greifswald. He died of angina pectoris. He is known today for the " Arndt-Schulz rule", a pharmacologic principle of homeopathy that is named in conjunction with German chemist Hugo Schulz (1853-1932). He is also remembered f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
