|
Prohormone
A prohormone is a committed Precursor (chemistry), precursor of a hormone consisting of peptide hormones synthesized together that has a minimal hormonal effect by itself because of its expression-suppressing structure, often created by protein folding and binding additional peptide chains to certain ends, that makes hormone receptor binding sites located on its peptide hormone chain segments inaccessible. Prohormones can travel the blood stream as a hormone in an inactivated form, ready to be activated later in the cell by post-translational modification. The body naturally produces prohormones as a way to regulate hormone expression, making them an optimal storage and transportation unit for inactive hormones. Once prohormones are needed to be expressed, prohormone convertase, a protein, cleaves the prohormones and separates them into one or more active hormones. Often in nature, this cleaving process happens immediately, and a prohormone is quickly converted to a set of one or mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Performance-enhancing Substance
Performance-enhancing substances, also known as performance-enhancing drugs (PEDs), are substances that are used to improve any form of activity performance in humans. A well-known example of cheating in sports involves doping in sport, where banned physical performance-enhancing drugs are used by athletes and bodybuilders. Athletic performance-enhancing substances are sometimes referred to as ergogenic aids. Cognitive performance-enhancing drugs, commonly called nootropics, are sometimes used by students to improve academic performance. Performance-enhancing substances are also used by military personnel to enhance combat performance. The use of performance-enhancing drugs spans the categories of legitimate use and substance abuse. Definition The classifications of substances as performance-enhancing substances are not entirely clear-cut and objective. As in other types of categorization, certain prototype performance enhancers are universally classified as such (like anaboli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prohormone Convertase
Proprotein convertases (PPCs) are a family of proteins that activate other proteins. Many proteins are inactive when they are first synthesized, because they contain chains of amino acids that block their activity. Proprotein convertases remove those chains and activate the protein. The prototypical proprotein convertase is furin. Proprotein convertases have medical significance, because they are involved in many important biological processes, such as cholesterol synthesis. Compounds called proprotein convertase inhibitors can block their action, and block the target proteins from becoming active. Many proprotein convertases, especially furin and PACE4, are involved in pathological processes such as viral infection, inflammation, hypercholesterolemia, and cancer, and have been postulated as therapeutic targets for some of these diseases. History The phenomenon of prohormone conversion was discovered by Donald F. Steiner while examining the biosynthesis of insulin in 1967. At the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androgen Prohormone
An androgen prohormone, or proandrogen, is a prohormone (or prodrug) of an anabolic-androgenic steroid (AAS). They can be prohormones of testosterone or of synthetic compound, synthetic AAS, for example, nandrolone (19-nortestosterone). Dehydroepiandrosterone (DHEA), DHEA sulfate (DHEA-S), and androstenedione may all be considered proandrogens of testosterone. In the last two decades, prohormones have also been used by bodybuilders, athletes, and nonmedical users of AAS and other hormones to refer to substances that are expected to convert to active hormones in the body. The intent is to provide the benefits of taking an AAS without the legal risks, and to achieve the hoped-for benefits or advantages without use of AAS themselves. Many of these compounds are legal to manufacture, sell, possess and ingest eliminating the legal problems associated with schedule III AAS. This also enables chemists to further their legal research and get around the law (albeit for a short time). The ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preprohormone
A preprohormone is the precursor protein to one or more prohormones, which are in turn precursors to peptide hormones. In general, the protein consists of the amino acid chain that is created by the hormone-secreting cell, before any changes have been made to it. It contains a signal peptide, the hormone A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required ...(s) itself (themselves), and intervening amino acids. Before the hormone is released from the cell, the signal peptide and other amino acids are removed. References Signal transduction Protein targeting Peptide hormones Precursor proteins {{Biochem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehormone
A prehormone is a biochemical substance secreted by glandular tissue and has minimal or no significant biological activity, but it is converted in peripheral tissues into an active hormone. Calcifediol is an example of a prehormone which is produced by hydroxylation of vitamin D3 (cholecalciferol) in the liver. Another example is adrenal androgens like dehydroepiandrosterone and androstenedione, which can be converted into testosterone and dihydrotestosterone. See also * Prohormone A prohormone is a committed Precursor (chemistry), precursor of a hormone consisting of peptide hormones synthesized together that has a minimal hormonal effect by itself because of its expression-suppressing structure, often created by protein fol ... References Hormones {{Biochem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anabolic Steroid
Anabolic steroids, also known more properly as anabolic–androgenic steroids (AAS), are steroidal androgens that include natural androgens like testosterone (medication), testosterone as well as synthetic androgens that are structurally related and have similar effects to testosterone. They increase protein within cell (biology), cells, especially in skeletal muscles, and also have varying degrees of virilization, virilizing effects, including induction of the development and maintenance of male, masculine secondary sexual characteristics such as the growth of facial hair, facial and body hair. The word ''anabolic'', referring to anabolism, comes from the Greek ἀναβολή ''anabole'', "that which is thrown up, mound". Androgens or AAS are one of three types of sex hormone agonists, the others being estrogen (medication), estrogens like estradiol (medication), estradiol and progestogens like progesterone (medication), progesterone. AAS were synthesized in the 1930s, and are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Controlled Substances Act
The Controlled Substances Act (CSA) is the statute establishing federal government of the United States, federal drug policy of the United States, U.S. drug policy under which the manufacture, importation, possession, use, and distribution of certain substances is regulated. It was passed by the 91st United States Congress as Title II of the Comprehensive Drug Abuse Prevention and Control Act of 1970 and signed into law by President Richard Nixon. The Act also served as the national implementing legislation for the Single Convention on Narcotic Drugs. The legislation created five schedules (classifications), with varying qualifications for a substance to be included in each. Two federal agencies, the Drug Enforcement Administration (DEA) and the Food and Drug Administration (FDA), determine which substances are added to or removed from the various schedules, although the statute passed by Congress created the initial listing. Congress has sometimes scheduled other substances th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preproinsulin
Insulin (, from Latin ''insula'', 'island') is a peptide hormone produced by beta cells of the pancreatic islets encoded in humans by the ''INS'' gene. It is considered to be the main Anabolism, anabolic hormone of the body. It regulates the metabolism of carbohydrates, fats and protein by promoting the absorption of glucose from the blood into liver, fat cell, fat and skeletal muscle cells. In these tissues the absorbed glucose is converted into either glycogen via glycogenesis or Fatty acid metabolism#Glycolytic end products are used in the conversion of carbohydrates into fatty acids, fats (triglycerides) via lipogenesis, or, in the case of the liver, into both. Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in the blood. Circulating insulin also affects the synthesis of proteins in a wide variety of tissues. It is therefore an anabolic hormone, promoting the conversion of small molecules in the blood into large molecule ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signal Peptidase
Signal peptidases are enzymes that convert secretory and some membrane proteins to their mature or pro forms by cleaving their signal peptides from their N-termini. Signal peptidases were initially observed in endoplasmic reticulum (ER)-derived membrane fractions isolated from mouse myeloma cells. The key observation by César Milstein and colleagues was that immunoglobulin light chains were produced in a higher molecular weight form, which became processed by the ER membrane fraction. This finding was directly followed by the discovery of the translocation machinery. Signal peptidases are also found in prokaryotes as well as the protein import machinery of mitochondria and chloroplasts. All signal peptidases described so far are serine proteases. The active site that endoproteolytically cleaves signal peptides from translocated precursor proteins is located at the extracytoplasmic site of the membrane. The eukaryotic signal peptidase is an integral membrane protein Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Major League Baseball
Major League Baseball (MLB) is a professional baseball organization and the oldest major professional sports league in the world. MLB is composed of 30 total teams, divided equally between the National League (NL) and the American League (AL), with 29 in the United States and 1 in Canada. The NL and AL were formed in 1876 and 1901, respectively. Beginning in 1903, the two leagues signed the National Agreement and cooperated but remained legally separate entities until 2000, when they merged into a single organization led by the Commissioner of Baseball. MLB is headquartered in Midtown Manhattan. It is also included as one of the major professional sports leagues in the United States and Canada. Baseball's first all-professional team, the Cincinnati Red Stockings, was founded in 1869. Before that, some teams had secretly paid certain players. The first few decades of professional baseball were characterized by rivalries between leagues and by players who often jumped from one te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precursor (chemistry)
In chemistry, a precursor is a compound that participates in a chemical reaction that produces another compound. In biochemistry, the term "precursor" often refers more specifically to a chemical compound preceding another in a metabolic pathway, such as a protein precursor. Illicit drug precursors In 1988, the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances introduced detailed provisions and requirements relating the control of precursors used to produce drugs of abuse. In Europe the Regulation (EC) No. 273/2004 of the European Parliament and of the Council on drug precursors was adopted on 11 February 2004. ( European law on drug precursors) Illicit explosives precursors On January 15, 2013, the Regulation (EU) No. 98/2013 of the European Parliament and of the Council on the marketing and use of explosives precursors was adopted. The Regulation harmonises rules across Europe on the making available, introduction, possession and u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schedule III Drug
The Controlled Substances Act (CSA) is the statute establishing federal U.S. drug policy under which the manufacture, importation, possession, use, and distribution of certain substances is regulated. It was passed by the 91st United States Congress as Title II of the Comprehensive Drug Abuse Prevention and Control Act of 1970 and signed into law by President Richard Nixon. The Act also served as the national implementing legislation for the Single Convention on Narcotic Drugs. The legislation created five schedules (classifications), with varying qualifications for a substance to be included in each. Two federal agencies, the Drug Enforcement Administration (DEA) and the Food and Drug Administration (FDA), determine which substances are added to or removed from the various schedules, although the statute passed by Congress created the initial listing. Congress has sometimes scheduled other substances through legislation such as the Hillory J. Farias and Samantha Reid Date-Ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
