The short version of Research chemical fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-09-28. Anything still debated is marked as such rather than presented as settled.
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.
The compound is generally presented as a synthetic fragment of epithalamin, a pineal gland extract investigated in the former Soviet Union from the 1970s onward. Vladimir Khavinson and colleagues in Saint Petersburg developed short peptides modelled on such extracts, and epitalon became the most widely cited of those sequences. Most primary reports appeared in Russian-language journals or in proceedings with limited international circulation. Independent replication in laboratories outside that network remains sparse, and much repeated secondary material traces back to a small number of originating groups.
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.
Identity and purity are checked by reversed-phase high-performance liquid chromatography, usually with ultraviolet detection near 214 nanometres, where the peptide bond absorbs. Mass spectrometry confirms the expected mass and reveals whether truncation products or adducts are present. Acid hydrolysis followed by amino acid analysis gives the residue ratio, which should approximate one alanine, one glutamate, one aspartate and one glycine. Counter-ions such as acetate or trifluoroacetate remain in the dried product and lower net peptide content, so a stated purity figure on a label does not by itself describe how much peptide a vial holds.
Regulatory treatment differs by country. No formulation of epitalon holds a marketing authorisation as a medicine in the United States or the European Union, where material sold for laboratory use is handled as a research chemical and is not intended for human consumption. In Russia, several short peptide preparations from the same institute's peptide series are registered medicinal products, and epitalon appears in that national context. Elsewhere it is frequently offered as a cosmetic ingredient, a category with lighter requirements. Advertising claims about longevity or disease prevention are restricted in most jurisdictions, which limits how sellers describe the compound.
Freeze-dried epitalon is normally kept at minus twenty degrees Celsius in a sealed, desiccated container, protected from light. Short excursions at ambient temperature during shipping are generally tolerated, but repeated warming and cooling cycles encourage moisture uptake, which shortens shelf life. Once dissolved, the peptide is far less stable than the solid: aqueous solutions are subject to hydrolysis and to deamidation at the aspartate and glutamate residues. Working solutions are therefore held refrigerated and used within days, and repeated freezing and thawing of the same vial is best avoided.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Computed for the free acid of Ala-Glu-Asp-Gly |
| Molecular mass | About 390.35 g/mol | Free peptide; salt forms shift the value |
| Appearance | White to off-white solid | Typical of short peptides after freeze-drying |
| Solubility class | Freely soluble in water | Aqueous buffers are also commonly used |
| Common synonyms | Epitalon, epithalone, AEDG | AEDG is the single-letter sequence |
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 four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
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.
The most widely cited claim is that epitalon activates telomerase and thereby extends telomere length. Supporting evidence comes largely from cultured human cells, where treatment was associated with increased telomerase activity and delayed replicative senescence. Telomerase activation is a biologically consequential effect, since the enzyme is largely silenced in most somatic cells. However, the route by which a short peptide would reach and act on the enzyme's regulatory machinery has not been established. Independent replication in human trials is scarce, so the link between cell-culture observations and whole-body aging remains an open question.
Human data are limited to small studies, often without the randomization, blinding, or control groups expected in contemporary clinical research. Reported outcomes have included changes in melatonin levels, immune markers, and subjective measures, but sample sizes were generally too small to support firm conclusions. Some reviews treat the peptide as promising while noting methodological weaknesses; others question whether the observed effects are specific. The compound is frequently discussed in longevity-focused communities, where enthusiasm often outpaces the published evidence. Separating established findings from speculation is therefore important when reading summaries of this research.
Lutetium usually occurs in association with the element yttrium and is sometimes used in metal alloys and as a catalyst in various chemical reactions. 177Lu-DOTA-TATE is used for radionuclide therapy (see Nuclear medicine) on neuroendocrine tumours. Lutetium has the highest Brinell hardness of any lanthanide, at 890–1300 MPa.
14 September NASA releases its first public study on UAP (also known as UFOs), and appoints Mark McInerney as the first Director of UAP, to scientifically and transparently study further such occurrences. A new record time for quantum coherence is reported, with a single-photon qubit encoded in a novel superconducting cavity for 34 milliseconds. A genetically engineered marine microorganism is shown to break down polyethylene terephthalate in salt water. This plastic, used in everything from water bottles to clothing, is a significant contributor to microplastic pollution in oceans. A study finds that rivers are warming and losing oxygen faster than oceans. Of nearly 800 rivers, warming occurred in 87% and oxygen loss occurred in 70%. The study projects that within 70 years, river systems could "induce acute death" and extinctions of aquatic species due to long low oxygen levels. Astronomers report studies related to the Hubble tension, a disagreement in results attempting to measure the Hubble constant, and find that the results from the James Webb Space Telescope support earlier results from the Hubble Space Telescope. According to astronomer Adam Riess, "With Webb confirming the measurements from Hubble, the Webb measurements provide the strongest evidence yet that systematic errors in Hubble's Cepheid photometry do not play a significant role in the present Hubble tension ...
==== European Union ==== The European Union's (EU) Food Supplements Directive of 2002 requires that supplements be demonstrated to be safe, both in dosages and in purity. Only those supplements that have been proven to be safe may be sold in the EU without prescription. As a category of food, food supplements cannot be labeled with drug claims but can bear health claims and nutrition claims. The dietary supplements industry in the United Kingdom (UK), one of the 28 countries in the bloc, strongly opposed the Directive. In addition, a large number of consumers throughout Europe, including over one million in the UK, and various doctors and scientists, had signed petitions by 2005 against what are viewed by the petitioners as unjustified restrictions of consumer choice. In 2004, along with two British trade associations, the Alliance for Natural Health (ANH) had a legal challenge to the Food Supplements Directive referred to the European Court of Justice by the High Court in London. Although the European Court of Justice's Advocate General subsequently said that the bloc's plan to tighten rules on the sale of vitamins and food supplements should be scrapped, he was eventually overruled by the European Court, which decided that the measures in question were necessary and appropriate for the purpose of protecting public health. ANH, however, interpreted the ban as applying only to synthetically produced supplements, and not to vitamins and minerals normally found in or consumed as part of the diet.
== Methods of detection and analysis == The most sensitive method of detecting and measuring EDTA in biological samples is selected reaction monitoring capillary electrophoresis mass spectrometry (SRM-CE/MS), which has a detection limit of 7.3 ng/mL in human plasma and a quantitation limit of 15 ng/mL. This method works with sample volumes as small as 7–8 nL. EDTA has also been measured in non-alcoholic beverages using high performance liquid chromatography (HPLC) at a level of 2.0 μg/mL.
Sources: en.wikipedia.org
Jung identified two primary 'attitudinal types'—introvert and extrovert. While the terms 'introversion' and 'extraversion' had prior use in European thought, Jung was the first to integrate them into a comprehensive structural theory of personality. He redefined these concepts not merely as social traits, but as fundamental directions of psychic energy (libido), establishing the first systematic model of psychological types based on the movement of psychic energy libido toward the subject or the object. In Psychological Types, Jung defined the primary attitudinal types (introvert and extrovert), comparing them to the ancient archetypes: Apollo and Dionysus. The introvert is likened to Apollo, who shines a light on understanding. The introvert is focused on the internal world of reflection, dreaming, and vision. Thoughtful and insightful, the introvert can sometimes be uninterested in joining the activities of others. The introvert's libido flows inwards towards subjective factors and is influenced by 'inner necessity'. By contrast, the extravert is associated with Dionysus, interested in joining the activities of the world. The extravert is focused on the outside world of objects, sensory perception, and action. Energetic and lively, the extravert may lose their sense of self in the intoxication of Dionysian pursuits. For the extravert, the libido flows outwards, and the person has an interest, relationship and dependence on events, people and things. Jung's concepts of introversion and extraversion differ fundamentally from their common usage in modern trait psychology.
Dover grew further after the Norman invasion of 1066 as a member of the Confederation of Cinque Ports. After the martyrdom of Archbishop Thomas Becket at Canterbury Cathedral in 1170, Dover flourished as the only designated port of entry for foreign pilgrims and as a point of departure for the third and subsequent crusades. Following Edward III's success at the Battle of Sluys in 1340, a large defensive wall was built around the town. Although few concerted attempts to manage the shingle deposits blocking the harbour entrance were made during the late Middle Ages, a short pier and two defensive towers were constructed at the port in years immediately prior to Henry VIII's departure to the royal summit known as the Field of the Cloth of Gold in 1520.
Observatories, astronomical – Andean and Mesoamerican astronomers constructed towers to observe the movements of the planets and other astronomical features and events. Although culture groups throughout the world have observed the planets and stars and recorded their movements, the stone structures of the Mesoamerican and Andean culture groups are significant because they show the emphasis these early astronomers placed on making clear and accurate observations. In the U.S., the Anasazi built structures with windows aligned for the observation of celestial events. The most notable example of Maya astronomical observatories is Caracol, in Chichén Itzá. In 1975, archaeoastronomers Anthony F. Aveni and Horst Hartung surveyed the site and suggested that ancient Maya astronomers used the structure to observe the planet Venus. The Maya, as well as other Mesoamerican culture groups, used Venus to set times for ceremonies and as a divination tool.
NAD(P)H dehydrogenase [quinone] 1 is an enzyme that in humans is encoded by the NQO1 gene. This protein-coding gene is a member of the NAD(P)H dehydrogenase (quinone) family and encodes a 2-electron reductase (enzyme). This FAD-binding protein forms homodimers and performs two-electron reduction of quinones to hydroquinones and of other redox dyes. It has a preference for short-chain acceptor quinones, such as ubiquinone, benzoquinone, juglone and duroquinone. This gene has an important paralog NQO2. This protein is located in the cytosol. NQO1 enzyme expression can be induced by dioxin and inhibited by dicoumarol.
== Research == The Life Sciences Institute is a multidisciplinary basic science research institute, with focal strengths in chemical and structural biology. Its 23 faculty members lead labs specializing in a wide range of life sciences disciplines, including:
Sources: en.wikipedia.org
== Manufacturing == LED manufacturing involves multiple steps, including epitaxy, chip processing, chip separation, and packaging. In a typical LED manufacturing process, encapsulation is performed after probing, dicing, die transfer from wafer to package, and wire bonding or flip chip mounting, perhaps using indium tin oxide, a transparent electrical conductor. In this case, the bond wire(s) are attached to the ITO film that has been deposited in the LEDs. Flip chip circuit on board (COB) is a technique that can be used to manufacture LEDs.
Alexander McLeish. For services to Charity. Martin Gerard McTague. Low Pay Commissioner and National Chair, UK Federation of Small Businesses. For services to Small Businesses. Thomas Anthony Meadows. Lead Operations Manager, Security Services Group, Defence Infrastructure Organisation. For services to Defence. Dr. Teame Mebrahtu. For services to Education, to Refugees and to the community in Bristol. Dr. Nicholas John Merriman. Chief Executive, The Horniman Museum and Gardens. For services to the Arts and to Heritage. Gillian Jayne Millane. Co-Founder, Love Grace. For services to Charitable Fundraising and Tackling Violence Against Women. Dr. Jane Patricia Monckton-Smith. Professor of Public Protection, University of Gloucestershire. For services to Criminal Justice. Keith Morgan. Coach, Crystal Palace Weightlifting Club. For services to Sport. Andrew David Murphy. Lately Chief Operating Officer, John Lewis Partnership. For services to the British Retail Industry. Professor James Michael Olu N'Dow, DL. Professor of Urological Surgery, University of Aberdeen. For services to Cancer and Urology, and to Voluntary Work. Professor Kimberley Anne-Isola Nekaris. Head, Nocturnal Primate Research Group, Oxford Brookes University. For services to Conservation. Kenneth Paul Newton. Governing Governor, HM Prison Birmingham. For Public Service. Robert Stewart Nicol. Lately Chief Executive, Inverness Chambers of Commerce. For services to the Economy of the Highlands of Scotland. Beryce Amy Nixon. Chief Executive Officer, Exceed Learning Partnership Trust. For services to Education.
=== Laboratory Analysers === Automated analysers, by the association of robotics and spectrophotometry, have allowed these last decades better reproducibility of the results, in particular in medical biochemistry and hematology. Efficiency and productivity can be enhanced by automating the pre-analytical processing, including barcode reading, sorting, centrifuging, and aliquoting specimens. The analysers must undergo daily controls prior to performing patient testing. Analysers must also undergo daily, weekly and monthly maintenance. Quality management involves reviewing quality control trends to detect emerging problems in instrument calibration, correlating results between instruments that perform similar testing, and running standardized samples to prove linearity and precision. Some laboratory processes involve automated analysis combined with manual review by technologists. For example, when hematology analysers flag samples as abnormal, automated white blood cell differential counts may be superseded by manual differential counts using stained slides read at the microscope or scanned by digital imaging software. Laboratory technologists may flag abnormal samples for pathologist review. The pathologist may recommend additional testing, such as flow cytometry to identify lymphoma or leukemia cells, or cytology to characterize solid tumor cells.
Such an inflexible dosing regime limits the utility benzodiazepines offer in practice; e.g. lorazepam and alprazolam can be used as needed for situational anxiety in which continuous use is unnecessary or excessive, while clonazepam can be titrated to response when continuous relief is indicated, up to a maximum of 4 mg a day, four times greater than the dose used in comparison with etifoxine over the 24 week duration of the trial. In general, they offer a degree of personalization that is not possible with etifoxine. Indeed, better evidence is required before etifoxine can be said to replace benzodiazepines in practice, especially considering the trials above were relatively small in size, along with the high attrition rates and lack of personalization of the benzodiazepines used. The usual dosage of etifoxine (as the hydrochloride salt) is 150 to 200 mg per day in divided doses of 50 to 100 mg two to three times per day (e.g., 50 mg–50 mg–100 mg). It is taken for a few days to a few weeks, but no longer than 12 weeks.
Sources: en.wikipedia.org
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.
Epitalon and epithalon both circulate, and the difference reflects transliteration of a name coined in Russian-language publications. Reference to the extract it derives from, epithalamin, explains the shared stem. Databases and suppliers are inconsistent, so a search for one spelling alone may miss relevant entries.
No. Epithalamin is a multi-component preparation obtained from pineal tissue, and its exact composition is not fully characterised. Epitalon is a single defined tetrapeptide described as a short synthetic counterpart of that extract, so the two are related in origin but not interchangeable in identity.
The solid is kept cold, dry and dark, typically at minus twenty degrees Celsius, in a sealed container with desiccant. Dissolved material is kept refrigerated and used promptly. Freezing and thawing a solution repeatedly is avoided because it accelerates degradation.