The short version of tetrapeptide fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-02-14 and is reviewed periodically as new material appears.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Synthetic tetrapeptide, four residues |
| Nominal mass | Approximately 390 Da | Free peptide; salt forms differ |
| Appearance | White to off-white powder | Commonly supplied lyophilised |
| Solubility class | Freely soluble in water | Also dissolves in aqueous buffer |
| Typical storage | −20 °C, desiccated | Cold packs used during transport |
Storage recommendations center on limiting moisture, heat, and light. The dry powder is generally kept at minus 20 degrees Celsius, and some suppliers recommend minus 80 degrees for long-term archival. Once dissolved, solutions are usually aliquoted and frozen to avoid repeated freeze-thaw cycles, which can promote aggregation or degradation. Aqueous stability depends on pH and concentration, and buffered saline is often preferred over plain water for biological work. Stability data specific to epitalon remain limited, so general peptide-handling practices are applied by analogy rather than from product-specific validation.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and its calculated monoisotopic mass is approximately 390.35 daltons. The compound does not occur naturally as a free peptide; it is produced by solid-phase peptide synthesis. Because it contains two acidic residues and no basic residues, the neutral form carries a net negative charge at physiological pH. This charge profile influences how the peptide behaves in solution and during chromatographic analysis.
Laboratory-grade epitalon is typically supplied as a lyophilized powder. Purity is commonly assessed with reverse-phase high-performance liquid chromatography, often paired with mass spectrometry to confirm molecular identity. Amino acid analysis and peptide mapping can provide additional confirmation of sequence. Certificates of analysis for research materials frequently report purity above 95 percent, although the methods behind such figures vary between suppliers. The absence of a pharmacopeial monograph means that no single standardized assay defines the compound, so reported results depend on the analytical protocol chosen.
== Notable alumni == Tassaduq Hussain Jillani, 21st Chief Justice of Pakistan Samar Mubarakmand, nuclear physicist Nawabzada Nasrullah Khan, politician Makhdoom Sajjad Hussain Qureshi, former Governor of Punjab Inzamam-ul-Haq, cricketer and former captain of the Pakistan national cricket team Syed Jamshed Ali, former judge of the Supreme Court of Pakistan Faiz Mohammad Khan, medical physicist specialising in radiation oncology Mazhar Kaleem, novelist Tauqeer Nasir, actor and former director-general of the Pakistan National Council of the Arts Muhammad Ali, Lollywood actor Mohsin Naqvi, Urdu poet Irshad Hussain, chemist and nanomaterials scientist Khalid Masood Khan, poet and columnist Ehsan Wyne, lawyer and politician
He also helped fund much research, through the iron foundry which he owned and directed. His statue is prominently placed in front of the Gallery of Evolution. Following the French Revolution the MNHN was reorganised, with twelve professorships of equal rank. Some of its early professors included eminent comparative anatomist Georges Cuvier and the pioneers of the theory of evolution, Jean-Baptiste de Lamarck and Étienne Geoffroy Saint-Hilaire. The museum's aims were to instruct the public, put together collections and conduct scientific research. The naturalist Louis Jean Marie Daubenton wrote extensively about biology for the pioneer French Encyclopédie, and gave his name to several newly discovered species. The museum sent its trained botanists on scientific expeditions around the world. Major figures in the MNHN included Déodat de Dolomieu, who gave his name to the mineral dolomite and to a volcano on Réunion island, and the botanist Rene Desfontaines, who spent two years collecting plants for study Tunisia and Algeria, and whose book "Flora Atlantica" (1798–1799, 2 vols), added three hundred genera new to science. When Napoleon Bonaparte launched his military campaign to conquer Egypt in 1798, his army was accompanied by more than 154 scientists, including botanists, chemists, mineralogists, including Étienne Geoffroy Saint-Hilaire, Vivant Denon, Joseph Fourier, and Claude Louis Berthollet, who together took back a large quantity of specimens and illustrations to enrich the collections of the museum.
== Plot == Timofey Berezin (Paddy Considine) works at a former top-secret, badly run and aged nuclear reprocessing facility plant in Skotoprigonyevsk-16, a former closed city and a naukograd. At the film's outset, he is exposed to radioactive contamination while selflessly trying to prevent a critical malfunction. The facility's managers tell him that his exposure was a survivable 100 rems, while accusing him of sabotage and suspending him without pay. Loyal coworkers, however, help Timofey discover the truth that he was exposed to 1,000 rems of radiation. Suffering from acute radiation poisoning, he has only days to live. Before Timofey's adoring wife, Marina (Radha Mitchell), is fully aware of his fate, he leaves for Moscow, on a mission to secure a better future for her and their young son. He hooks up with a small-time gangster, Shiv (Oscar Isaac), in hopes of finding a buyer for a selfmade canister of a little over 100 grams of weapons-grade plutonium salt he has stolen. It is 1995, only a few years after the dissolution of the Soviet Union, and they spend their time frequenting the hotels, nightclubs and private palaces of the new Moscow underworld, ricocheting between two rival crime lords (Nikolaj Lie Kaas and Steven Berkoff). However, what Timofey and Shiv never realize is that they are both caught in the same dilemma: trying to find a way free of a certain fate; hoping to do right by their loved ones before it is too late.
=== Biological computers === A biological computer refers to an engineered biological system that can perform computer-like operations, which is a dominant paradigm in synthetic biology. Researchers built and characterized a variety of logic gates in a number of organisms, and demonstrated both analog and digital computation in living cells. They demonstrated that bacteria can be engineered to perform both analog and/or digital computation. In 2007, in human cells, research demonstrated a universal logic evaluator that operates in mammalian cells. Subsequently, researchers utilized this paradigm to demonstrate a proof-of-concept therapy that uses biological digital computation to detect and kill human cancer cells in 2011. In 2016, another group of researchers demonstrated that principles of computer engineering can be used to automate digital circuit design in bacterial cells. In 2017, researchers demonstrated the 'Boolean logic and arithmetic through DNA excision' (BLADE) system to engineer digital computation in human cells. In 2019, researchers implemented a perceptron in biological systems opening the way for machine learning in these systems.
Sources: en.wikipedia.org
Two Boer forces fought in this area, under Botha in the south east and under Ben Viljoen in the north east around Lydenburg. Botha's forces were particularly active, raiding railways and British supply convoys, and mounting a renewed invasion of Natal in September 1901. After defeating British mounted infantry in the Battle of Blood River Poort near Dundee, Botha was forced to withdraw by heavy rain that made movement difficult and crippled his horses. Back on the Transvaal territory around his home district of Vryheid, Botha attacked a British raiding column at Bakenlaagte, using an effective mounted charge. One of the most active British units was effectively destroyed. This made Botha's forces the target of increasingly large scorched earth drives by British forces, in which the British made particular use of native scouts and informers. Eventually, Botha had to abandon the high veld and retreat to a narrow enclave bordering Swaziland. To the north, Ben Viljoen grew steadily less active. His forces mounted comparatively few attacks and as a result, the Boer enclave around Lydenburg was largely unmolested. Viljoen was eventually captured.
=== Infants and microwave ovens === There are several cases of child abuse where an infant or child has been placed in a microwave oven. The typical feature of such injuries are well-defined burns on the skin nearest to the microwave emitter, and histology examination shows higher damage extent in tissues with high content of water (e.g., muscles) than in tissues with less water (e.g., adipose tissue). One such case involved a teenage babysitter who admitted to having placed a child in the microwave oven for approximately sixty seconds. The child developed a third degree burn to the back, measuring 5 inches x 6 inches. The babysitter later took the child to the emergency department, where multiple skin grafts were placed on the back. There were no signs of lasting emotional, cognitive or physical effects. CT scan of the head was normal, and there were no cataracts. Another case involved a five-week-old female infant that had multiple full-thickness burns totaling 11% of the body surface area. The mother claimed the infant had been near a microwave oven, but not inside it. The infant survived but required amputations of parts of one leg and one hand. Additionally, there have been two alleged infant deaths caused by microwave ovens. In all these cases, the babies were placed within microwaves and died of subsequent injuries.
==== Carbon ==== Stable isotope analysis of carbon in human bone collagen allows bioarchaeologists to carry out dietary reconstruction and to make nutritional inferences. These chemical signatures reflect long-term dietary patterns, rather than a single meal or feast. Isotope ratios in food, especially plant food, are directly and predictably reflected in bone chemistry, allowing researchers to partially reconstruct recent diet using stable isotopes as tracers. Stable isotope analysis monitors the ratio of carbon 13 to carbon 12 (13C/12C), which is expressed as parts per thousand using delta notation (δ13C). The 13C and 12C ratio is either depleted (more negative) or enriched (more positive) relative to a standard. 12C and 13C occur in a ratio of approximately 98.9 to 1.1.
Paul Berg, a Nobel laureate in chemistry, wrote to the Senate that "Quackery will always prey on the gullible and uninformed, but we should not provide it with cover from the NIH," and called the office "an embarrassment to serious scientists". Allen Bromley, then-president of the American Physical Society, similarly wrote to Congress that the OAM had "emerged as an undiscriminating advocate of unconventional medicine. It has bestowed the considerable prestige of the NIH on a variety of highly dubious practices, some of which clearly violate basic laws of physics". Leon Jaroff, writing for The New York Times in 1997, described the OAM as "Tom Harkin's folly". In 1995, Wayne Jonas, a promoter of homeopathy and political ally of Harkin, became the director of the OAM, and continued in that role until 1999. In 1997, the NCCAM budget was increased from $12 million to $20 million annually. From 1990 to 1997, use of alternative medicine in the US increased by 25%, with a corresponding 50% increase in expenditures. The OAM drew increasing criticism from eminent members of the scientific community with letters to the Senate Appropriations Committee when discussion of renewal of funding OAM came up. In 1998, the President of the North Carolina Medical Association publicly called for shutting down the OAM. In 1998, NIH director and Nobel laureate Harold Varmus came into conflict with Harkin by pushing to have more NIH control of alternative medicine research. The NIH Director placed the OAM under stricter scientific NIH control.
Atoltivimab/maftivimab/odesivimab, sold under the brand name INMAZEB, is a fixed-dose combination of three monoclonal antibodies for the treatment of ebola caused by Zaire ebolavirus. It was developed by Regeneron Pharmaceuticals and contains three human monoclonal antibodies, atoltivimab, maftivimab, and odesivimab-ebgn. The most common side effects include fever, chills, tachycardia (fast heart rate), tachypnea (fast breathing), and vomiting; however, these are also common symptoms of Ebola virus infection. Atoltivimab/maftivimab/odesivimab is the first FDA-approved treatment for Zaire ebolavirus. Atoltivimab/maftivimab/odesivimab was approved for medical use in the United States in October 2020. The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication. It is on the World Health Organization's List of Essential Medicines. Atoltivimab/maftivimab/odesivimab is indicated for the treatment of infection caused by Zaire ebolavirus.
Sources: en.wikipedia.org
No. Epithalamin is a heterogeneous peptide fraction obtained from pineal gland extract and contains many components. Epitalon is a single synthetic tetrapeptide with the sequence Ala-Glu-Asp-Gly. Researchers synthesised the shorter peptide while attempting to identify active sequences within the extract.
No endogenous peptide with this exact sequence has been described as a circulating hormone or signalling molecule. The tetrapeptide was designed as a synthetic analogue based on fragments observed in pineal preparations. Any activity discussed in the literature therefore refers to administered material rather than to a natural pool of the compound.
It is not an approved medicine in major jurisdictions and does not appear in the major pharmacopoeias. Material is usually distributed as a research chemical or laboratory reagent. Such labelling places handling responsibility on the purchaser and does not indicate that a regulatory body has reviewed the substance.
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.