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Xenohormone
Xenohormones or environmental hormones are compounds produced outside of the human body that exhibit endocrine hormone-like properties. They may be either of natural origin, such as phytoestrogens, which are derived from plants, or of synthetic origin. These compounds can cause endocrine disruption by multiple mechanisms including acting directly on hormone receptors, affecting the levels of natural hormones in the body, and by altering the expression of hormone receptors. The most commonly occurring xenohormones are xenoestrogens, which mimic the effects of estrogen. Other xenohormones include xenoandrogens (anabolic-androgenic steroids) and xenoprogesterones. Xenohormones are used for a variety of purposes including contraceptive & hormonal therapies, and agriculture. However, exposure to certain xenohormones early in childhood development can lead to a host of developmental issues including infertility, thyroid complications, and early onset of puberty. Exposure to others late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hormone
A hormone (from the Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physiology and behavior. Hormones are required for the normal development of animals, plants and fungi. Due to the broad definition of a hormone (as a signaling molecule that exerts its effects far from its site of production), numerous kinds of molecules can be classified as hormones. Among the substances that can be considered hormones, are eicosanoids (e.g. prostaglandins and thromboxanes), steroids (e.g. Estrogen, oestrogen and brassinosteroid), amino acid derivatives (e.g. epinephrine and auxin), protein or peptides (e.g. insulin and CLE peptides), and gases (e.g. ethylene and nitric oxide). Hormones are used to communicate between organ (anatomy), organs and Tissue (biology), tissues. In vertebrates, hormones are responsible for regulating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endocrine
The endocrine system is a messenger system in an organism comprising feedback loops of hormones that are released by internal glands directly into the circulatory system and that target and regulate distant organs. In vertebrates, the hypothalamus is the neural control center for all endocrine systems. In humans, the major endocrine glands are the thyroid, parathyroid, pituitary, pineal, and adrenal glands, and the (male) testis and (female) ovaries. The hypothalamus, pancreas, and thymus also function as endocrine glands, among other functions. (The hypothalamus and pituitary glands are organs of the neuroendocrine system. One of the most important functions of the hypothalamusit is located in the brain adjacent to the pituitary glandis to link the endocrine system to the nervous system via the pituitary gland.) Other organs, such as the kidneys, also have roles within the endocrine system by secreting certain hormones. The study of the endocrine system and its disorde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycoestrogen
Mycoestrogens are xenoestrogens produced by fungi. They are sometimes referred to as estrogenic mycotoxins. Some important mycoestrogens are zearalenone, zearalenol and zearalanol. Although all of these can be produced by various ''Fusarium'' species, zearalenol and zearalanol may also be produced endogenously in ruminants that have ingested zearalenone. Alpha-zearalanol is also produced semisynthetically, for veterinary use; such use is prohibited in the European Union. Mechanism of action Mycoestrogens act as agonists of the estrogen receptors, ERα and ERβ. Sources Mycoestrogens are produced by various strains of fungi, many of which fall under the genus ''Fusarium''. ''Fusarium'' fungi are filamentous fungi that are found in the soil and are associated with plants and some crops, especially cereals. Zearalenone is mainly produced by ''F. graminearum'' and ''F. culmorum'' strains, which inhabit different areas depending on temperature and humidity. ''F. graminearum'' pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytoestrogen
A phytoestrogen is a plant-derived xenoestrogen (a type of estrogen produced by organisms other than humans) not generated within the endocrine system, but consumed by eating plants or manufactured foods. Also called a "dietary estrogen", it is a diverse group of naturally occurring nonsteroidal plant compounds that, because of its structural similarity to estradiol (17-β-estradiol), have the ability to cause both estrogenic or antiestrogenic effects. Phytoestrogens are not essential nutrients because their absence from the diet does not cause a disease, nor are they known to participate in any normal biological function. Common foods containing phytoestrogens are soybeans and soy protein concentrate, miso, tempeh, and tofu. Some soy-based infant formulas manufactured with soy protein contain isoflavones. Its name comes from the Greek ''phyto'' ("plant") and ''estrogen'', the hormone which gives fertility to female mammals. The word "estrus" (Greek οίστρος) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androgen Receptor
The androgen receptor (AR), also known as NR3C4 (nuclear receptor subfamily 3, group C, member 4), is a type of nuclear receptor that is activated by binding any of the androgenic hormones, including testosterone and dihydrotestosterone, in the cytoplasm and then translocating into the Cell nucleus, nucleus. The androgen receptor is most closely related to the progesterone receptor, and progestins in higher dosages can block the androgen receptor. The main function of the androgen receptor is as a DNA-binding protein, DNA-binding transcription factor that Gene expression regulation, regulates gene expression; however, the androgen receptor has other functions as well. Androgen-regulated genes are critical for the development and maintenance of the male sexual phenotype. Function Effect on development In some cell types, testosterone interacts directly with androgen receptors, whereas, in others, testosterone is converted by 5-alpha reductase, 5-alpha-reductase to dihydrot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endosulfan
Endosulfan is an organochlorine insecticide and acaricide, which acts by blocking the GABA-gated chloride channel of the insect (Insecticide Resistance Action Committee#Table of modes of action and classes of insecticide, IRAC group 2A). It became highly controversial due to its acute toxicity, potential for bioaccumulation, and role as an endocrine disruptor. Because of its threats to human health and the environment, a global ban on the manufacture and use of endosulfan was negotiated under the Stockholm Convention in April 2011. The ban took effect in mid-2012, with certain uses exempted for five additional years. More than 80 countries, including the European Union, Australia, New Zealand, several West African nations, the United States,Cone, MarlaEPA Bans Pesticide Found on Cucumbers, Zucchini, Green Beans and Other Vegetables. ''The Daily Green.'' June 10, 2010. Brazil, and Canada had already banned it or announced phase-outs by the time the Stockholm Convention ban was agreed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methoxychlor
Methoxychlor is a synthetic organochloride insecticide, now obsolete. Tradenames for methoxychlor include ''Chemform'', ''Maralate'', ''Methoxo'', ''Methoxcide'', ''Metox'', and ''Moxie''. Usage Methoxychlor was used to protect crops, ornamentals, livestock, and pets against fleas, mosquitoes, cockroaches, and other insects. It was intended to be a replacement for DDT, but has since been banned for use as a pesticide based on its acute toxicity, bioaccumulation, and endocrine disruption activity. The amount of methoxychlor in the environment changes seasonally due to its use in farming and foresting. It does not dissolve readily in water, so it is mixed with a petroleum-based fluid and sprayed, or used as a dust. Sprayed methoxychlor settles on the ground or in aquatic ecosystems, where it can be detected in sediments. Its degradation may take many months. Methoxychlor is ingested and absorbed by living organisms, and it accumulates in the food chain. Some metabolites may have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bisphenol A
Bisphenol A (BPA) is a chemical compound primarily used in the manufacturing of various plastics. It is a colourless solid which is Solubility, soluble in most common organic solvents, but has very poor solubility in water. BPA is produced on an industrial scale by the condensation reaction of phenol and acetone. Global production in 2022 was estimated to be in the region of 10 million tonnes. BPA's largest single application is as a co-monomer in the production of polycarbonates, which accounts for 65–70% of all BPA production. The manufacturing of epoxy resins and vinyl ester resins account for 25–30% of BPA use. The remaining 5% is used as a major component of several high-performance plastics, and as a minor additive in polyvinyl chloride (PVC), polyurethane, thermal paper, and several other materials. It is not a plasticizer, although it is often wrongly labelled as such. The health effects of BPA have been the subject of prolonged public and scientific debate. BPA is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Postpartum Period
The postpartum (or postnatal) period begins after childbirth and is typically considered to last for six to eight weeks. There are three distinct phases of the postnatal period; the acute phase, lasting for six to twelve hours after birth; the subacute phase, lasting six weeks; and the delayed phase, lasting up to six months. During the delayed phase, some changes to the genitourinary system take much longer to resolve and may result in conditions such as urinary incontinence. The World Health Organization (WHO) describes the postnatal period as the most critical and yet the most neglected phase in the lives of mothers and babies. Most maternal and newborn deaths occur during this period. In scientific literature, the term is commonly abbreviated to P''x'', where ''x'' is a number; for example, "day P5" should be read as "the fifth day after birth". This is not to be confused with the medical nomenclature that uses G P to stand for number and outcomes of pregnancy ( gravidit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phthalates
Phthalates ( ), or phthalate esters, are esters of phthalic acid. They are mainly used as plasticizers, i.e., substances added to plastics to increase their flexibility, transparency, durability, and longevity. They are used primarily to soften polyvinyl chloride (PVC). While phthalates are commonly used as plasticizers, not all plasticizers are phthalates. The two terms are specific, unique, and not used interchangeably. Lower-molecular-weight phthalates are typically replaced in many products in the United States, Canada, and European Union over health concerns. They are being replaced by higher molecular-weight phthalates as well as non-phthalic plasticizers. Phthalates are commonly ingested in small quantities via the diet. One of the most commonly known phthalates is bis(2-ethylhexyl) phthalate (DEHP). In many countries, DEHP is regulated as a toxin, and is banned from use in broad categories of consumer goods, such as cosmetics, children's toys, medical devices, and fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receptor Antagonist
A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. Antagonist drugs interfere in the natural operation of receptor proteins.Pharmacology Guide: In vitro pharmacology: concentration-response curves ." '' GlaxoWellcome.'' Retrieved on December 6, 2007. They are sometimes called blockers; examples include alpha blockers, beta b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agonist
An agonist is a chemical that activates a Receptor (biochemistry), receptor to produce a biological response. Receptors are Cell (biology), cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an Receptor antagonist, antagonist blocks the action of the agonist, while an inverse agonist causes an action opposite to that of the agonist. Etymology The word originates from the Ancient Greek, Greek word (''agōnistēs''), "contestant; champion; rival" < (''agōn''), "contest, combat; exertion, struggle" < (''agō''), "I lead, lead towards, conduct; drive." Types of agonists Receptor (biochemistry), Receptors can be activated by either endogenous agonists (such as hormones and neurotransmitters) or exogenous agonists (such as medication, drugs), resulting in a biological response. A physiological agonism an ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
