The short version of Khavinson fits in a sentence. The long version — which is the one that helps — is below.
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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.
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.
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.
Epitalon emerged from research conducted in Saint Petersburg by Vladimir Khavinson and colleagues, who studied short peptides as potential regulators of aging. The work built on epithalamin, a pineal gland extract reported to influence neuroendocrine function. Epitalon was designed as a synthetic counterpart with a defined sequence, allowing reproducible experiments that extracts could not support. Early publications described effects on melatonin rhythms and lifespan in animal models. These findings circulated mainly in Russian-language journals during the 1990s, which limited their visibility among English-speaking researchers.
| 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 |
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.
Epitalon appears in the literature primarily through a small number of research groups, most of them associated with the St. Petersburg Institute of Bioregulation and Gerontology. Publications describe cell culture experiments, animal studies, and a limited number of small human studies. Independent replication outside this network is sparse. As a result, reviews of the topic usually separate descriptive reports of observed effects from the question of whether those effects generalize, and they note the difficulty of comparing studies that use different preparations and endpoints.
Analytical characterization of epitalon relies on standard peptide methods. Reverse-phase high-performance liquid chromatography is used to assess purity, and mass spectrometry confirms identity by checking the observed mass against the expected value near 390 daltons. Amino acid analysis can verify composition. Because the peptide is short and hydrophilic, it elutes early on many reverse-phase columns, so method development often requires ion-pairing reagents to achieve adequate retention and resolution from related impurities.
Reported biological findings come mainly from cell culture and rodent experiments. Those studies describe changes in telomerase catalytic subunit expression, melatonin rhythm amplitude, and antioxidant enzyme activity after peptide exposure. Human data are sparse and consist of small trials with limited blinding and inconsistent endpoints. The proposed mechanisms remain hypotheses rather than established facts, and there is no consensus on whether effects observed in animals carry over to people. Independent replication outside the original research groups is limited, which is a recognised gap in the published literature.
The parent extract epithalamin was characterised as a low-molecular-weight fraction of pineal tissue rather than a single defined chemical entity. Researchers fractionated it and tested successive fragments for activity, a screening approach typical of peptide discovery work in that era. Epitalon emerged from that process as one of the shorter sequences of interest. Because the original extract was never fully resolved into individual components, claims about which constituent drives a given effect rest on inference. This distinction matters when reading older reports that attribute extract observations to the tetrapeptide itself.
Epitalon is a synthetic tetrapeptide with the residue sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its monoisotopic mass is approximately 390.35 daltons, and it is usually supplied as a lyophilised trifluoroacetate or acetate salt. The compound was derived from a pineal gland extract called epithalamin, a heterogeneous preparation investigated in the former Soviet Union. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology described the tetrapeptide as a constituent fragment of that extract. Commercial material is offered as a laboratory reagent rather than as a finished pharmaceutical product.
=== Magnetic confinement fusion === In fusion devices, such as tokamaks and stellarators, ICRH antennas are installed in the machine vessel to heat the plasma using radio waves with frequencies in the range of the ion cyclotron resonance. ICRH provides localized heating of ions in fusion plasmas, which can generate a large population of energetic particles typically inaccessible with other heating methods (such as electron cyclotron resonance heating or neutral beam injection). The confinement properties of fast ions in plasma is a major research topic in fusion plasma physics.
According to Bucknell, SN 35.106 describes a non-linear "branched version" of dependent origination in which consciousness is derived from the coming together of the sense organs and the sense objects (and thus represents sense perception). The Mahānidānasutta (DN 15) describes a "looped version", in which consciousness and nama-rupa condition each other. It also describes consciousness descending into the womb. According to Bucknell, "some accounts of the looped version state explicitly that the chain of causation goes no further back than the loop. Waldron also mentions idea that in early Buddhism, consciousness may have been understood as having these two different aspects (basic consciousness or sentience and cognitive sense consciousness). While these two aspects were largely undifferentiated in early Buddhist thought, these two aspects and their relation was explicated in later Buddhist thought, giving rise to the concept of alaya-vijñana. In yet another linear version, dubbed the "Sutta-nipata version", consciousness is derived from avijja ("ignorance") and saṅkhāra ("activities" also translated as "volitional formations").
=== Belgium === Following the Belgian general election held on 13 June 2010, a process of cabinet formation started in Belgium. The election produced a very fragmented political landscape, with 11 parties elected to the Chamber of Representatives, none of which won more than 20% of the seats. The Flemish-Nationalist New Flemish Alliance (N-VA), the largest party in Flanders and the country as a whole, controlled 27 of 150 seats in the lower chamber. The Francophone Socialist Party (PS), the largest in Wallonia, controlled 26 seats. Cabinet negotiations continued for a long time. On 1 June 2011, Belgium matched the record for time taken to form a new democratic government after an election, at 353 days, held until then by Cambodia in 2003–2004. On 11 October 2011, the final agreement for institutional reform was presented to the media. A government coalition was named on 5 December 2011 and sworn in after a total of 541 days of negotiations and formation on 6 December 2011, and 589 days without an elected government with Elio Di Rupo named Prime Minister of the Di Rupo I Government. It was the first time that the Belgian prime minister had been openly gay, as Di Rupo became the world's first male openly gay head of government (and second of any gender, after Iceland's Jóhanna Sigurðardóttir). Elio Di Rupo also became the first native French-speaking prime minister since 1979 and the first prime minister from Wallonia since 1974 and first socialist prime minister since 1974.
The topology of a β-sheet describes the order of hydrogen-bonded β-strands along the backbone. For example, the flavodoxin fold has a five-stranded, parallel β-sheet with topology 21345; thus, the edge strands are β-strand 2 and β-strand 5 along the backbone. Spelled out explicitly, β-strand 2 is H-bonded to β-strand 1, which is H-bonded to β-strand 3, which is H-bonded to β-strand 4, which is H-bonded to β-strand 5, the other edge strand. In the same system, the Greek key motif described above has a 4123 topology. The secondary structure of a β-sheet can be described roughly by giving the number of strands, their topology, and whether their hydrogen bonds are parallel or antiparallel. β-sheets can be open, meaning that they have two edge strands (as in the flavodoxin fold or the immunoglobulin fold) or they can be closed β-barrels (such as the TIM barrel). β-Barrels are often described by their stagger or shear. Some open β-sheets are very curved and fold over on themselves (as in the SH3 domain) or form horseshoe shapes (as in the ribonuclease inhibitor). Open β-sheets can assemble face-to-face (such as the β-propeller domain or immunoglobulin fold) or edge-to-edge, forming one big β-sheet.
Sources: en.wikipedia.org
=== Energy intake === 5-HT2C receptor agonists reduce appetite by working on serotonin receptors in a region of the brain called the hypothalamus. Lorcaserin (Belviq) was FDA approved for weight loss but was withdrawn from the market because a safety clinical trial shows an increased occurrence of cancer. Cannabinoid receptor antagonists were developed to treat obesity because researchers noticed that cannabinoid agonists (such as THC, the main pharmacologically active component of cannabis), increased appetite. However, some drugs in this class such as rimonabant were withdrawn or ceased development due to concerns about mental health and suicide. More selective drugs—some are in development that act only in peripheral tissues, not the brain—may be able to achieve this result with fewer adverse effects. GLP-1 agonists such as tirzepatide, semaglutide, and liraglutide slow gastric emptying and also have neurologically driven effects on appetite. It is unknown if GLP-1 agonists or dual/triple agonists of GLP-1 and/or the glucagon or GIP receptors act solely by reducing energy intake or if they also increase energy expenditure. Setmelanotide is an agonist of the melanocortin 4 receptor and is used in people with certain rare genetic conditions that cause obesity. It is less effective and not approved for general obesity.
=== Meat tenderizing and other uses === Along with papain, bromelain is one of the most popular proteases to use for meat tenderizing. Bromelain is sold in a powdered form, which is combined with a marinade, or directly sprinkled on the uncooked meat. Cooked or canned pineapple does not have a tenderizing effect, as the enzymes are heat-labile and denatured in the cooking process. Some prepared meat products, such as meatballs and commercially available marinades, include pineapple or pineapple-derived ingredients. Although the quantity of bromelain in a typical serving of pineapple fruit is probably fairly minimal, specific extraction can yield sufficient quantities for domestic and industrial processing, including uses in baking, anti-browning of cut fruit, textiles and cosmetics manufacturing.
The College of Medicine was established by Daniel Drake in 1819 as the Medical College of Ohio, which was the first college of medicine established in the state of Ohio. It became a part of the University of Cincinnati in 1896 and is considered by some historians to be the oldest medical school west of the Allegheny Mountains. It is supposedly the second-oldest public college of medicine in the United States. Other accomplishments include the development of the heart-lung machine, the Fogarty heart catheter, Benadryl, and the Clark oxygen electrode. The college also established the nation's first residency program in emergency medicine. The college is noted for its neurosurgical research into degenerative diseases including Alzheimer's disease and Parkinson's disease. Ranked in the top one-third of American medical schools, the college attracts students from across the United States. In 2008, it became the first medical college in the country to implement the multiple mini interview system pioneered in Canada to better predict candidates with exceptional interpersonal skills, professionalism and ethical judgment. Other medical schools have since adopted the process. In addition to the usual application pathways, the University of Cincinnati offers a dual-admissions program known as Connections to high school students applying for undergraduate studies at the university where students are guaranteed admission to the school if they acquire the required grade point average and MCAT scores. The college attracts many undergraduate students to its summer research fellowships.
Using various modifiers, the activity of the enzyme can be regulated, enabling control of the biochemistry of the cell as a whole. The structure of proteins is traditionally described in a hierarchy of four levels. The primary structure of a protein consists of its linear sequence of amino acids; for instance, "alanine-glycine-tryptophan-serine-glutamate-asparagine-glycine-lysine-...". Secondary structure is concerned with local morphology (morphology being the study of structure). Some combinations of amino acids will tend to curl up in a coil called an α-helix or into a sheet called a β-sheet; some α-helixes can be seen in the hemoglobin schematic above. Tertiary structure is the entire three-dimensional shape of the protein. This shape is determined by the sequence of amino acids. In fact, a single change can change the entire structure. For example, the beta chain of hemoglobin contains 146 amino acid residues; substitution of the glutamate residue at position 6 with a valine residue changes the behavior of hemoglobin so much that it results in sickle-cell disease. Finally, quaternary structure is how separately polypeptide chains interact with one another to form the final protein. This applies only to proteins composed of multiple chains, such as hemoglobin with its four subunits, whereas many others have only one chain.
==== Intramuscular or subcutaneous ==== Naloxone can also be administered via intramuscular or subcutaneous injection. The onset of naloxone provided through this route is 2 to 5 minutes with a duration of around 30–120min. Naloxone administered intramuscularly are provided through pre-filled syringes, vials, and auto-injector. A hand-held auto-injector is pocket-sized and can be used in non-medical settings such as in the home. It is designed for use by laypersons, including family members and caregivers of opioid users at risk for an opioid emergency, such as an overdose. According to the FDA's National Drug Code Directory, a generic version of the auto-injector began to be marketed at the end of 2019.
Sources: en.wikipedia.org
30 July – The Parliamentary Commissioner for Standards launches an investigation into Nigel Farage over a potential breach of parliamentary rules over financial interests. Former Downing Street Chief of Staff Sue Gray is appointed to the board of governors of Queen's University Belfast. Adam Holloway, the former Conservative MP for Gravesham, defects to Reform UK. 31 July – James Orr, chairman of the pro-Reform UK think tank, the Centre for a Better Britain, tells the Today programme an incoming Reform government would have to do some "very unpopular" things in its first 100 days in office and force "nasty cough medicine down the country's throat" but that if "Reform ends up governing the country, we should all want them to succeed".
=== Optic disc drusen === NAION in patients with optic disc drusen has unique characteristics: earlier onset, history of transient visual disturbances, and generally better visual outcomes. Mechanical pressure from drusen on blood vessels near the optic nerve may contribute to NAION development in these individuals.
Direct skin contact with nickel-releasing item Prolonged skin contact with nickel-releasing item A sufficient amount of nickel is released and absorbed into the skin to cause a reaction The pathophysiology is divided into induction elicitation phases. Induction is the critical phase (immunological event) when skin contact to nickel results in antigen presentation to the T cells, and T cell duplication (cloning) occurs. The metal cation Ni++ is a low molecular weight hapten that easily penetrates the stratum corneum (top layer of skin). Nickel then binds to skin protein carriers creating an antigenic epitope. The determining factor in sensitization is exposure of significant amounts of "free nickel". This is important because different metal alloys release different amounts of free nickel. The antigenic epitope is collected by dermal dendritic cells and Langerhans cells, the antigen-presenting cells (APC) of the skin, and undergo maturation and migration to regional lymph nodes. The complex is predominantly expressed on major histocompatibility complex (MHC) II, which activates and clonally expands naive CD4+ T cells. Upon re-exposure these now primed T cells will be activated and massively recruited to the skin, resulting in the elicitation phase and the clinical presentation of Ni-ACD. Although ACD has been considered a Th1 predominate process, recent studies highlight a more complex picture. In Ni-ACD other cells are involved including: Th17, Th22, Th1/IFN and the innate immune responses consistent with toll-like receptor 4.
Hot dogs are prepared commercially by mixing the ingredients (meats, spices, binders and fillers) in vats where rapidly moving blades grind and mix the ingredients in the same operation. This mixture is forced through tubes into casings for cooking. Most hot dogs sold in the US are "skinless" rather than "natural casing" sausages.
=== Reactivity === The reactivities of the alkali metals increase going down the group. This is the result of a combination of two factors: the first ionisation energies and atomisation energies of the alkali metals. Because the first ionisation energy of the alkali metals decreases down the group, it is easier for the outermost electron to be removed from the atom and participate in chemical reactions, thus increasing reactivity down the group. The atomisation energy measures the strength of the metallic bond of an element, which falls down the group as the atoms increase in radius and thus the metallic bond must increase in length, making the delocalised electrons further away from the attraction of the nuclei of the heavier alkali metals. Adding the atomisation and first ionisation energies gives a quantity closely related to (but not equal to) the activation energy of the reaction of an alkali metal with another substance. This quantity decreases going down the group, and so does the activation energy; thus, chemical reactions can occur faster and the reactivity increases down the group.
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.
Vladimir Khavinson and colleagues at research institutes in Saint Petersburg developed and studied the peptide. Their program examined short peptides as regulators of aging and neuroendocrine function. Epitalon was one of several compounds produced by that group.