The short version of epithalamin fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-07-27. Anything still debated is marked as such rather than presented as settled.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
Epitalon is a synthetic tetrapeptide whose sequence is alanine-glutamate-aspartate-glycine, written in single-letter code as AEDG. The four residues are joined by three peptide bonds, giving a linear backbone with no branching and no disulfide bridges. Its calculated molecular mass for the free form is approximately 390.3 daltons, a figure that rises when the compound is supplied as an acetate or trifluoroacetate salt. Because the chain is short, the molecule is defined entirely by its residue order rather than by any folded three-dimensional structure.
Identity is normally established by reversed-phase high-performance liquid chromatography combined with mass spectrometry, a pairing that separates components and confirms molecular mass at once. Purity is quoted as a percentage from the chromatogram, and figures above ninety-five percent are a frequent commercial specification. Amino acid analysis or sequencing supplies further confirmation when required. Because many short peptides behave similarly under chromatography, retention time alone does not establish sequence; the mass measurement is what separates one tetrapeptide from another, and certificates should report both.
Short peptides such as AEDG are normally supplied as a freeze-dried solid and are kept dry, cold, and shielded from light. Holding at minus twenty degrees Celsius is common for the long term, while a refrigerator suffices for brief periods before use. The material takes up moisture to some degree, so containers should stay sealed and be allowed to reach room temperature before opening, which limits condensation on the contents. Repeated warming and cooling of a single container is discouraged because it admits water and can lower the amount of intact peptide.
Dissolution is usually performed in water or a suitable aqueous buffer, and the resulting liquid is divided into single-use portions before freezing. Freeze-thaw cycling is a recognised source of loss for short peptides, since each cycle can encourage aggregation or adsorption onto container walls. Working solutions are generally kept cold and used within a short window, although published stability data specific to epitalon are thin. Containers should be marked with concentration and date, and solutions examined for cloudiness before use.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four residues, linear chain |
| Residue sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG |
| Calculated mass | 390.3 daltons | Value for the free, uncharged form |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility | Freely soluble in water | Often handled as a salt form |
The compound is generally described as a synthetic analogue of a fragment isolated from a pineal gland extract. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology introduced it during the 1980s and 1990s while studying short peptides from animal tissue. The original extract, called epithalamin, is a heterogeneous mixture, whereas epitalon is a single defined sequence. That distinction matters because findings reported for the extract are not automatically findings about the pure tetrapeptide, and claims about broader biological effects remain a separate question from the chemical identity described here.
Residue composition is the property that most cleanly separates verified material from mislabelled samples. Alanine, glutamate, aspartate and glycine appear in that order from the N-terminus, and the two acidic residues sit in the middle of the chain. Because the peptide is short, it can be produced by solid-phase synthesis and characterised by mass spectrometry without ambiguity. Any reported sample whose measured mass departs substantially from 390 daltons is a different compound or a degraded mixture rather than epitalon.
Epitalon is a synthetic tetrapeptide whose four residues are alanine, glutamate, aspartate and glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9 and its monoisotopic mass is near 390.35 daltons. The peptide carries two acidic side chains, so it is neutral to negatively charged in most aqueous buffers. Published reference summaries usually list it under both spellings, epitalon and epithalon, and treat the two names as the same material.
Purity assessment of peptide reagents normally relies on reversed-phase high-performance liquid chromatography. A gradient of acetonitrile in water with trifluoroacetic acid, paired with a C18 stationary phase, separates the target tetrapeptide from truncated sequences and deletion analogues. Detection at 214 nanometres exploits absorbance of the peptide backbone, since the molecule contains no aromatic residue. Results are expressed as a percentage of total peak area. Values above ninety-five percent are typical for research-grade material, although reporting conventions vary between suppliers.
Identity confirmation uses mass spectrometry, usually electrospray ionisation in positive mode or matrix-assisted laser desorption. The protonated free peptide produces a signal near three hundred and ninety-one daltons, while salt adducts shift that value slightly. Tandem mass spectrometry or amino acid analysis supplies sequence-level confirmation, which a single mass measurement cannot. Peptides containing aspartate can cyclise into succinimide intermediates that hydrolyse to isoaspartate isomers of identical mass. Because those isomers are difficult to separate chromatographically, identity and purity results carry more weight when interpreted together.
The peptide is a synthetic analogue of epithalamin, a preparation extracted from bovine pineal glands. Investigators sought a short, chemically defined molecule that would reproduce some of the endocrine and gerontological observations attributed to the glandular extract. Proposed mechanisms centre on induction of telomerase activity, an effect reported in cultured human somatic cells in the early 2000s, together with influences on melatonin secretion and neuroendocrine regulation. Those mechanisms remain incompletely characterised, and the reported telomerase response has not been consistently reproduced by independent groups working in comparable systems.
Published work on this compound consists mainly of in vitro experiments, animal studies, and small clinical investigations, a substantial share of which appeared in Russian-language journals. Sample sizes are generally small, control conditions differ between studies, and several endpoints rely on markers whose clinical meaning is itself debated. Reviews of the longevity field treat the peptide as an early example of telomerase-directed research rather than an established intervention. Regulatory treatment varies by country: some jurisdictions place it under prescription controls, others treat it as a laboratory material, and importation may be restricted regardless of local status.
== Cartridges == The stationary phase comes in the form of a packed syringe-shaped cartridge, a 96 well plate, a 47- or 90-mm flat disk, or a microextraction by packed sorbent (MEPS) device, a SPE method that uses a packed sorbent material in a liquid handling syringe. These can be mounted on its specific type of extraction manifold. The manifold allows multiple samples to be processed by holding several SPE media in place and allowing for an equal number of samples to pass through them simultaneously. In a standard cartridge SPE manifold up to 24 cartridges can be mounted in parallel, while a typical disk SPE manifold can accommodate 6 disks. Most SPE manifolds are equipped with a vacuum port, where vacuum can be applied to speed up the extraction process by pulling the liquid sample through the stationary phase. The analytes are collected in sample tubes inside or below the manifold after they pass through the stationary phase. Solid phase extraction cartridges and disks can be purchased with several stationary phases, each of which separates analytes depending on different chemical properties. The basis of most stationary phases is silica that has been bonded to a specific functional group. Some of these functional groups include hydrophobic alkyl or aryl chains of variable length (for reversed phase), quaternary ammonium or amino groups (for anion exchange), and aliphatic sulfonic acid or carboxyl groups (for cation exchange).
Radon is a naturally occurring radioactive noble gas discovered in 1900 by Friedrich Ernst Dorn (1848-1916) and is considered carcinogenic. Radon is increasingly found in areas with high levels of uranium and thorium in the soil. These are mainly areas with high granitic rock deposits. According to studies by the World Health Organization, the incidence of lung cancer increases significantly at radiation levels of 100-200 Bq per cubic meter of indoor air. The likelihood of developing lung cancer increases by 10% with each additional 100 Bq/m3 of indoor air.
Disease testing: Whether the sex of the fetus is male or female allows the determination of the risk of a particular X-linked recessive genetic disorder in a particular pregnancy, especially where the mother is a genetic carrier of the disorder. Preparation, for any sex-dependent aspects of parenting. Sex selection, which after preimplantation genetic diagnosis may be performed by selecting only embryos of the preferred sex, or, after post-implantation methods by performing sex-selective abortion depending on the test result and personal preference. In comparison to obstetric ultrasonography which is unreliable for sex determination in the first trimester and amniocentesis which carries a small risk of miscarriage, sampling of maternal plasma for analysis of cffDNA is without risk. The main targets in the cffDNA analysis are the gene responsible for the sex-determining region Y protein (SRY) on the Y chromosome and the DYS14 sequence.
Independent research: this would be work done with core or flexible funding that allows the researchers the liberty to choose their research questions and method. It may be long term and could emphasize 'big ideas' without direct policy relevance. However, it could emphasize a major policy problem that requires a thorough research and action investment. Consultancy: this would be work done by commission with specific clients and addressing one or two major questions. Consultancies often respond to an existing agenda. Influencing/advocacy: this would be work done by communications, capacity development, networking, campaigns, lobbying, etc. It is likely to be based on research based evidence emerging from independent research or consultancies. Second, policy institutes may base their work or arguments on:
aid, though it was under the first five years of the Plan Colombia. In March 2015, it was revealed DEA agents were participating in drug cartel-funded sex parties with prostitutes. Agents were provided with expensive gifts, weapons, and money from drug cartel members. As a result, the head of the US Drug Enforcement Administration, Michele Leonhart, announced her retirement. According to the 2022 Truth Commission report, the 2019 arrest of Jesús Santrich on drug trafficking charges, which was a joint operation by the DEA and Colombian Attorney General Néstor Humberto Martínez, was intended to send a message from the Colombian Attorney General's to the Colombian public that the peace process had failed. Santrich's arrest led to hundreds of ex-guerrillas taking up arms again, which jeopardized the peace process.
Sources: en.wikipedia.org
== History == In 1908, what appears to be the first case of Urbach–Wiethe disease was reported by Friedrich Siebenmann, a professor of otolaryngology in Basel, Switzerland. In 1925, Friedrich Miescher, a Swiss dermatologist, reported on three similar patients. An official report of Urbach–Wiethe disease was first described in 1929 by a Viennese dermatologist and otorhinolaryngologist, Urbach and Wiethe. Its original name of 'lipoidosis cutis et mucosae' was changed to 'lipoid proteinosis cutis et mucosae' due to Urbach's belief that the condition was due to abnormal lipid and protein deposits within the tissues. Some have debated as to whether or not the disease is actually a form of mucopolysaccharidosis, amyloidosis, or even porphyria. The discovery of the Urbach–Wiethe disease causing mutation to the ECM1 gene has now provided a definitive way to differentiate Urbach–Wiethe disease from these other conditions. A woman with Urbach–Wiethe disease, S.M., was a woman unable to feel fear. She has been extensively studied, which helped determine the function of the amygdala.
Seafood is any form of sea life regarded as food by humans, prominently including fish and shellfish. Shellfish include various species of molluscs (e.g., bivalve molluscs such as clams, oysters, and mussels, and cephalopods such as octopus and squid), crustaceans (e.g. shrimp, crabs, and lobster), and echinoderms (e.g. sea cucumbers and sea urchins). Historically, marine mammals such as cetaceans (whales and dolphins) as well as seals have been eaten as food, though that happens to a lesser extent in modern times. Edible sea plants such as some seaweeds and microalgae are widely eaten as sea vegetables around the world, especially in Asia. Seafood is an important source of (animal) protein in many diets around the world, especially in coastal areas. Semi-vegetarians who consume seafood as the only source of meat are said to adhere to pescetarianism. The harvesting of wild seafood is usually known as fishing or hunting, while the cultivation and farming of seafood is known as aquaculture and fish farming (in the case of fish). Most of the seafood harvest is consumed by humans, but a significant proportion is used as fish food to farm other fish or rear farm animals. Some seafoods (i.e. kelp) are used as food for other plants (a fertilizer). In these ways, seafoods are used to produce further food for human consumption. Also, products such as fish oil, spirulina tablets, fish collagen, and chitin are made from seafoods. Some seafood is fed to aquarium fish, or used to feed domestic pets such as cats.
===== Stimulation of natural killer (NK) cells ===== Experiments with UV-inactivated SeV showed that NK cells are important in virus-mediated inhibition of tumor growth. This was shown in a mouse model of renal cancer, in which the anti-tumor effect of SeV was suppressed by reducing the number of NK cells by co-injection of specific antibodies. The activation of NK requires several receptors, among which are natural killer proteins 46 (NKp46) and 44 (NKp44). Studies have shown that the only paramyxovirus protein that activates NK is HN. HN protein binding to NKp46 and/or NKp44 results in the lysis of cells whose surfaces display the HN protein or its fragments. It can be assumed that NK activation and tumor suppression by UV-treated SeV are caused by interaction between HN belonging to SeV, and NKp46 and/or NKp44 receptors belonging to NK cells.
== Th22 in diseases == Th22 has both pathologic and protective claimed roles when maintaining immunologic homeostasis. However, the role of Th22 in pathological processes has not been completely identified.
Sources: en.wikipedia.org
== Abstracting and indexing == The journal is abstracted and indexed in Biological Abstracts, Chemical Abstracts, Current Contents/Life Sciences, EMBiology, Food Science and Technology Abstracts, MEDLINE, Science Citation Index and Scopus.
), the trajectories of molecules can be traced out explicitly and used to compute macroscopic liquid properties like density or viscosity. However, classical MD requires expressions for the intermolecular forces ("F" in Newton's second law). Usually, these must be approximated using experimental data or some other input.
Trump renewed his talk of annexing Greenland, an autonomous territory of the Kingdom of Denmark, with CNBC noting that this prompted more serious concerns in the wake of Maduro's capture. The US already operates a military base in Greenland, Pituffik Space Base, and Denmark has indicated its openness to a heightened US military presence there, but Trump has been uninterested in anything less than a full US takeover, noting "that's what I feel is psychologically needed for success. I think that ownership gives you a thing that you can't do with, you're talking about a lease or a treaty. Ownership gives you things and elements that you can't get from just signing a document" and "When we own it, we defend it. You don't defend leases the same way, you have to own it". Asked "Psychologically important to you or to the United States?", he said: "Psychologically important for me." Hours after the strikes Katie Miller, wife of White House Deputy Chief of Staff Stephen Miller, posted a picture of a Greenland in the colors of the American flag with the caption "SOON" on X, prompting a rebuke from Denmark's ambassador to the US that "we expect full respect" for Denmark's territorial integrity and the two countries, being close allies, should continue to work as such.
The history of the mole is intertwined with that of units of molecular mass, and the Avogadro constant. The first table of standard atomic weight was published by John Dalton (1766–1844) in 1805, based on a system in which the relative atomic mass of hydrogen was defined as 1. These relative atomic masses were based on the stoichiometric proportions of chemical reaction and compounds, a fact that greatly aided their acceptance; it was not necessary for a chemist to subscribe to atomic theory (which was not universally accepted at the time) to make practical use of the tables. This would lead to some confusion between atomic masses (promoted by proponents of atomic theory) and equivalent weights (promoted by its opponents and which sometimes differed from relative atomic masses by an integer factor), which would last throughout much of the nineteenth century. Jöns Jacob Berzelius (1779–1848) was instrumental in the determination of relative atomic masses to ever-increasing accuracy. He was also the first chemist to use oxygen as the standard to which other masses were referred. Oxygen is a useful standard, as, unlike hydrogen, it forms compounds with most other elements, especially metals. However, he chose to fix the atomic mass of oxygen as 100, which did not catch on. Charles Frédéric Gerhardt (1816–56), Henri Victor Regnault (1810–78) and Stanislao Cannizzaro (1826–1910) expanded on Berzelius' works, resolving many of the problems of unknown stoichiometry of compounds, and the use of atomic masses attracted a large consensus by the time of the Karlsruhe Congress (1860).
== Additional information == Dhamara and adjacent villages are traditionally inhabited by fishermen since long and they depend on fishing and its allied activities to make their livelihood. Before 1980s these fishermen were very poor and their per capita income was below average with mud thatched roof houses. Now due to construction of harbour and its operation since 1978 onwards the living condition of the people have increased manifold. More than 40% of fishermen own fishing crafts and gears and have constructed good quality RCC house.
Sources: en.wikipedia.org
The peptide contains four residues in the order alanine, glutamate, aspartate and glycine, abbreviated AEDG. The chain is linear and held together by three peptide bonds. Its calculated mass for the uncharged free form is about 390.3 daltons.
Epithalamin refers to a crude preparation derived from bovine pineal tissue, which contains many components. Epitalon is a single synthetic tetrapeptide identified from that material and produced by chemical synthesis. The two names are sometimes confused because early reports treated the synthetic peptide as an active fragment of the extract.
It has been registered for clinical use in Russia, where it is associated with a small family of short peptides. In most other jurisdictions it is not an approved medicine and is traded as a research chemical. Regulatory status varies by country and changes over time.
Reversed-phase high-performance liquid chromatography is run alongside mass spectrometry. The chromatogram separates components and gives a purity figure, while the mass spectrum confirms that the measured molecular mass matches the expected sequence. Neither measurement on its own is treated as sufficient.