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  • Coumarin

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    Coumarin (; 2H-chromen-2-one) is a aromatic organic chemical compound in the benzopyrone chemical class, although it may also be seen as a subclass of lactones. It is a natural substance found in many plants, and a colorless crystalline substance in its standard state. The name comes from a French term for the tonka bean, coumarou, one of the sources from which coumarin was first isolated as a natural product in 1820. It has a sweet odor, readily recognised as the scent of newly-mown hay, and has been used in perfumes since 1882. Sweet woodruff, meadowsweet, sweet grass and sweet-clover in particular are named for their sweet (i.e., pleasant) smell, which in turn is related to their high coumarin content. When it occurs in high concentrations in forage plants, coumarin is a somewhat bitter-tasting appetite suppressant, and is presumed to be produced by plants as a defense chemical to discourage predation. Coumarin is used in certain perfumes and fabric conditioners. Coumarin has been used as an aroma enhancer in pipe tobaccos and certain alcoholic drinks, although in general it is banned as a flavorant food additive, due to concerns regarding its hepatotoxicity in animal models. Coumarin was first synthesized in 1868. It is used in the pharmaceutical industry as a precursor reagent in the synthesis of a number of synthetic anticoagulant pharmaceuticals similar to dicoumarol, the notable ones being warfarin (brand name Coumadin) and some even more potent rodenticides that work by the same anticoagulant mechanism. 4-hydroxycoumarins are a type of vitamin K antagonist. Pharmaceutical (modified) coumarins were all developed from the study of sweet clover disease; see warfarin for this history. However, unmodified coumarin itself, as it occurs in plants, has no effect on the vitamin K coagulation system, or on the action of warfarin-type drugs. Coumarin has clinical medical value by itself, as an edema modifier. Coumarin and other benzopyrones, such as 5,6-benzopyrone, 1,2-benzopyrone, diosmin, and others, are known to stimulate macrophages to degrade extracellular albumin, allowing faster resorption of edematous fluids. Other biological activities that may lead to other medical uses have been suggested, with varying degrees of evidence. Coumarin is also used as a gain medium in some dye lasers, and as a sensitizer in older photovoltaic technologies.

  • Nicotine

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    Nicotine is an antiherbivory alkaloid and potent parasympathomimetic stimulant found in plants, mostly those in the nightshade family. Nicotine acts as a receptor agonist at most nicotinic acetylcholine receptors (nAChRs), except at two nicotinic receptor subunits (nAChRα9 and nAChRα10) where it acts as a receptor antagonist. Nicotine is highly addictive. It is one of the most commonly abused drugs. An average cigarette yields about 2 mg of absorbed nicotine, while high amounts (30–60 mg) can be harmful. Nicotine induces both behavioral stimulation and anxiety in animals. Nicotine addiction involves drug-reinforced behavior, compulsive use, and relapse following abstinence. Nicotine dependence involves tolerance, sensitization, physical dependence, and psychological dependence. Nicotine dependency causes distress. Nicotine withdrawal symptoms include depressed mood, stress, anxiety, irritability, difficulty concentrating, and sleep disturbances. Mild nicotine withdrawal symptoms are measurable in unrestricted smokers, who experience normal moods only as their blood nicotine levels peak, with each cigarette. On quitting, withdrawal symptoms worsen sharply, then gradually improve to a normal state. Nicotine use as a tool for quitting smoking has a good safety history. There is inadequate data to establish if nicotine is itself a carcinogen, but there is evidence of possible risks. The health effects of long-term nicotine replacement use were unknown as of 2014. Overdose on nicotine-containing products results in nicotine poisoning. The use of electronic cigarettes, which are designed to be refilled with nicotine-containing e-liquid, has raised concerns over nicotine overdoses, especially with regard to the possibility of young children ingesting the liquids.

  • Cinnamon challenge

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    The cinnamon challenge involves consuming one spoonful of powdered cinnamon. The cinnamon challenge was a viral internet food challenge. The objective of the challenge is to film oneself eating a spoonful of ground cinnamon in under 60 seconds without drinking anything, then upload the video to the Internet. The challenge is difficult and carries substantial health risks because the cinnamon coats and dries the mouth and throat, resulting in coughing, gagging, vomiting and inhaling of cinnamon, leading to throat irritation, breathing difficulties, and risk of pneumonia or a collapsed lung. The challenge has been described online since 2001, and increased in popularity in 2007, peaking abruptly in January 2014 and falling off almost as sharply through the first half of that year, then tapering off almost to its previous level by 2014. By 2010, many people had posted videos of themselves attempting this challenge on YouTube and other social networking websites. The cinnamon challenge continues to be active, with Twitter mentions peaking at nearly 70,000 per day in January 2012.

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