A practical reference on AEDG: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-05-02 and is reviewed periodically as new material appears.
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.
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
Epitalon is the common name for a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, usually abbreviated AEDG. All four residues are proteinogenic amino acids, and the free peptide has a calculated mass near 390 grams per mole. Because the chain is short and carries no modifications, it is assembled readily by solid-phase synthesis and is distributed mainly as a freeze-dried solid for laboratory work. Catalogue listings use the spellings epitalon, epithalone, and simply AEDG, and the three refer to the same sequence.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Derived from the four constituent residues |
| Molecular mass | About 390.35 Da | Monoisotopic value, confirmed by mass spectrometry |
| Residue sequence | Ala-Glu-Asp-Gly | Read from the N-terminus to the C-terminus |
| Common synonyms | Epithalon; AEDG | Both forms appear in reference catalogues |
| Net charge near neutral pH | Negative | Two acidic side chains give a low isoelectric point |
The peptide emerged from research carried out in Saint Petersburg from the late 1980s onward, where investigators searched for shorter active fragments of a pineal preparation known as epithalamin. The name epitalon was chosen to reflect that parent extract. Early reports described effects on neuroendocrine markers and on the lifespan of laboratory animals. Much of that work appeared in Russian-language journals, with English translations following later, which affects how readily the original protocols can be assessed by outside groups.
Published studies on epitalon are dominated by a small number of research groups, and independent replication in other laboratories remains limited. Proposed mechanisms include activation of telomerase and modulation of melatonin rhythms, but the evidence for either rests mainly on cell cultures and animal models. Whether the peptide produces comparable effects in humans is an open question, and the absence of large controlled trials means the literature is best read as exploratory rather than settled.
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.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
Epitalon is a synthetic tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. Its design traces to epithalamin, a peptide fraction prepared from bovine pineal gland extracts that researchers in Saint Petersburg began investigating in the 1970s. The compound has a molecular formula of C14H22N4O9 and a nominal molecular mass near 390 daltons. It holds no approved drug status in the United States or the European Union, and material sold under this name is generally offered as a research chemical rather than a finished pharmaceutical product.
Proposed mechanisms centre on cell-culture observations rather than a defined receptor interaction. Several reports describe increased expression of the telomerase catalytic subunit after exposure of cultured human cells, and the authors attributed the effect to short peptide fragments entering the nucleus and influencing gene transcription. No receptor for the tetrapeptide has been identified, and the free peptide is expected to be degraded rapidly by plasma peptidases. Whether any measurable fraction reaches intact tissues after administration remains an unresolved question rather than an established finding.
The published literature is dominated by a small number of research groups, much of it in Russian-language journals, and independent replication outside those groups is limited. Studies are typically small, use cultured cells or rodent models, and report endpoints that differ between papers, which makes comparison difficult. Large randomised human trials have not appeared in the indexed literature. Questions about absorption, distribution and clearance are therefore still treated as open in reviews that mention the compound.
=== Studies of enzyme mechanism === Many proteins require the simultaneous or sequential binding of multiple substrates, cofactors, and/or allosteric effectors. Thermofluor studies of molecules that bind to active site subsites, cofactor sites, or allosteric binding sites can help elucidate specific features of enzyme mechanism that can be important in the design of effective drug screening campaigns and in characterizing novel inhibitory mechanisms.
cereus is also known to cause difficult-to-eradicate chronic skin infections, though less aggressive than necrotizing fasciitis. B. cereus can also cause keratitis. While often associated with gastrointestinal illness, B. cereus is also associated with illnesses such as fulminant bacterial infection, central nervous system involvement, respiratory tract infection, and endophthalmitis. Endophthalmitis is the most common form of extra-gastrointestinal pathogenesis, which is an infection of the eye that may cause permanent vision loss. Infections typically cause a corneal ring abscess, followed by other symptoms such as pain, proptosis, and retinal hemorrhage. While different from B. anthracis, B. cereus contains some toxin genes originally found in B. anthracis that are attributed to anthrax-like respiratory tract infections. A case study was published in 2019 of a catheter-related bloodstream infection of B. cereus in a 91-year-old male previously being treated with hemodialysis via PermCath for end-stage renal disease. He presented with chills, tachypnea, and high-grade fever, his white blood cell count and high-sensitivity C-reactive protein (CRP) were significantly elevated, and CT imaging revealed a thoracic aortic aneurysm. He was successfully treated for the infection with intravenous vancomycin, oral fluoroquinolones, and PermCath removal. Another case study of B. cereus infection was published in 2021 of a 30-year-old woman with lupus who was diagnosed with infective endocarditis after receiving a catheter. The blood samples were positive for B.
During the first episode of the series, Collins and her campmates were required to travel into the jungle via helicopter, however she refused to do so, becoming hysterical before the helicopter had taken off and was instead driven into camp. She and her fellow campmates Carl Fogarty, Craig Charles, Nadia Forde and Vicki Michelle were sent to live in the basic camp, "Celebrity Slammer", following a public vote prior to the series launch. After believing she had caught malaria and struggling with the lack of food, Collins withdrew from the series on the third day after spending 72 hours in the jungle. She was subject to online trolling and ridicule from the show's viewers after her exit, later revealing that she was attacked and robbed by a former boyfriend the day prior to flying out to Australia, as well as her mother's health issues, which contributed towards her reasons for quitting the show. Collins received a reduced fee for her appearance, the entirety of which she donated to the charity Save the Children. In August 2015, following the conclusion of the fifteenth series of The Only Way Is Essex, Collins announced she would be leaving the show after four years. However, she subsequently returned for the Christmas special episode of the sixteenth series and continued to appear on the programme sporadically for the next four years, with her appearances becoming less frequent in latter series due to her other commitments. She made her final appearance on the show during the twenty-fifth series in November 2019.
Zimelidine was introduced in 1982 and was the first SSRI to be sold. Despite its efficacy, a statistically significant increase in cases of Guillain–Barré syndrome among treated patients led to its withdrawal in 1983. Fluoxetine, introduced in 1987, is commonly thought to be the first SSRI to be marketed.
Following the first presidential debate of the general election, in which Obama's performance was considered surprisingly lackluster, his lead over Romney collapsed, putting pressure on Biden to stop the bleeding with a strong showing against the Republican vice-presidential nominee, Paul Ryan. Some political analysts considered Biden's performance in the October 11 vice-presidential debate one of the best of his career and a key factor in Obama's rebound in the polls and eventual victory. The debate also became memorable for the popularization of Biden's use of the phrase "a bunch of malarkey" in response to an attack by Ryan on the administration's response to the attacks on the U.S. embassy in Benghazi in September. Biden reused the phrase during his 2020 presidential campaign. On November 6, Obama and Biden were reelected.
Sources: en.wikipedia.org
where in aqueous solution H+ denotes a solvated proton. Often this is written as the hydronium ion H3O+, but this formula is not exact because in fact there is solvation by more than one water molecule and species such as H5O+2, H7O+3, and H9O+4 are also present. The equilibrium constant is given by
John Lilley states, "...neutron-induced fission generates extra neutrons which can induce further fissions in the next generation and so on in a chain reaction. The chain reaction is characterized by the neutron multiplication factor k, which is defined as the ratio of the number of neutrons in one generation to the number in the preceding generation. If, in a reactor, k is less than unity, the reactor is subcritical, the number of neutrons decreases and the chain reaction dies out. If k > 1, the reactor is supercritical and the chain reaction diverges. This is the situation in a fission bomb where growth is at an explosive rate. If k is exactly unity, the reactions proceed at a steady rate and the reactor is said to be critical. It is possible to achieve criticality in a reactor using natural uranium as fuel, provided that the neutrons have been efficiently moderated to thermal energies." Moderators include light water, heavy water, and graphite. According to John C. Lee, "For all nuclear reactors in operation and those under development, the nuclear fuel cycle is based on one of three fissile materials, 235U, 233U, and 239Pu, and the associated isotopic chains. For the current generation of LWRs, the enriched U contains 2.5~4.5 wt% of 235U, which is fabricated into UO2 fuel rods and loaded into fuel assemblies." Lee states, "One important comparison for the three major fissile nuclides, 235U, 233U, and 239Pu, is their breeding potential.
Between the summer of 2009 and March 2010, the use of mephedrone grew rapidly in the UK, with it becoming readily available at music festivals, head shops and on the internet. A survey of Mixmag readers in 2009, found it was the fourth most popular street drug in the United Kingdom, behind cannabis, cocaine, and ecstasy. The drug was used by a diverse range of social groups. Whilst the evidence was anecdotal, researchers, charity workers, teachers and users reported widespread and increasing use of the drug in 2009. The drug's rapid growth in popularity was believed to be related to both its availability and legality. In a book about drugs David Nutt reports the re-popularization story of mephedrone in a way that can be cross referenced with a report by Chemistry World in an article. Fiona Measham, a criminologist at the University of Lancaster, thought the emergence of mephedrone was also related to the decreasing purity of ecstasy and cocaine on sale in the UK, a view reinforced in a report by the National Treatment Agency for Substance Misuse. The average cocaine purity fell from 60% in 1999 to 22% in 2009 and about half of ecstasy pills seized in 2009 contained no MDMA, and by June 2010 almost all ecstasy pills seized in the UK contained no MDMA. A similar pattern was observed in the Netherlands, with the number of ecstasy tablets containing no MDMA rising from 10% in mid-2008 to 60% by mid-2009, with mephedrone being detected in 20% of ecstasy tablets by mid-2009.
Darmstadtium is a synthetic chemical element; it has symbol Ds and atomic number 110. It is extremely radioactive: the most stable known isotope, darmstadtium-281, has a half-life of approximately 14 seconds. Darmstadtium was first created in November 1994 by the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany, after which it was named. In the periodic table, it is a d-block transactinide element. It is a member of the 7th period and is placed in the group 10 elements, although no chemical experiments have yet been carried out to confirm that it behaves as the heavier homologue to platinum in group 10 as the eighth member of the 6d series of transition metals. Darmstadtium is calculated to have similar properties to its lighter homologues, nickel, palladium, and platinum.
Sources: en.wikipedia.org
==== Differential ==== A differential backup saves only the data that has changed since the last full backup. This means a maximum of two backups from the repository are used to restore the data. However, as time from the last full backup (and thus the accumulated changes in data) increases, so does the time to perform the differential backup. Restoring an entire system requires starting from the most recent full backup and then applying just the last differential backup. A differential backup copies files that have been created or changed since the last full backup, regardless of whether any other differential backups have been made since, whereas an incremental backup copies files that have been created or changed since the most recent backup of any type (full or incremental). Changes in files may be detected through a more recent date/time of last modification file attribute, and/or changes in file size. Other variations of incremental backup include multi-level incrementals and block-level incrementals that compare parts of files instead of just entire files.
Within seconds, D2R activation opens inwardly rectifying K+ channels, hyperpolarising the membrane and preventing voltage-gated Ca2+ influx, which halts exocytosis. Over minutes to hours, D2R suppresses adenylyl cyclase, lowering cAMP and reducing prolactin gene transcription. Chronically, D2R activates phosphotyrosine phosphatases and modulates ERK/MAPK pathways, inhibiting lactotroph proliferation. D2R-knockout mice develop lactotroph hyperplasia and frank prolactinomas, confirming the essential anti-proliferative role of dopaminergic signalling.
=== Restaurants === Stands and trucks sell boiled hot dogs at street and highway locations. Wandering hot dog vendors sell their product in baseball parks. At convenience stores, hot dogs are kept heated on rotating grills. Hot dogs are also common on restaurants' children's menus. Costco, a big-box retail chain, sells a yearly average of 135 million hot dogs at its food courts, at a notably low price. Fast-food restaurant chains typically do not carry hot dogs because of its shorter shelf-life, more complex toppings and cooking, and mismatched consumer expectations. There are also restaurants where hot dogs are a specialty.
Sources: en.wikipedia.org
It is a four-amino-acid peptide built from alanine, glutamate, aspartate and glycine in that order. Its formula is C14H22N4O9, and it is made by chemical synthesis rather than extracted from tissue. The synthetic peptide is a single defined molecule, unlike the pineal extracts it is often compared with.
No. The two spellings refer to the same tetrapeptide, and the difference reflects transliteration from Russian. Laboratories and catalogues use both forms interchangeably. The material is also indexed as AEDG, taken from the one-letter codes of its residues.
Epithalamin is a mixed preparation derived from animal pineal tissue and contains many peptides. Epitalon is one synthetic sequence chosen for study from that broader mixture. Statements about one do not transfer directly to the other.
It is a four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine. The chain is unmodified and contains only standard proteinogenic residues, which makes it straightforward to produce by solid-phase synthesis and to characterise by standard peptide methods.