This is a working overview of telomerase, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-04-19 and is reviewed periodically as new material appears.
The molecule is a short, linear, hydrophilic peptide that dissolves readily in water or aqueous buffer. Its principal chemical liabilities are hydrolytic rather than oxidative, since it contains no cysteine, methionine, or tryptophan residues. The aspartate–glycine step is a recognised site for aspartimide formation under mildly acidic or basic conditions, generating isoaspartate and succinimide-related products over time. Desiccated lyophilised powder held at −20 °C is comparatively stable, whereas dilute solutions degrade faster and are best frozen as single-use aliquots rather than thawed repeatedly.
No pharmacopoeial monograph exists for this peptide, so quality rests on the supplier's internal specifications and on whatever independent testing a purchaser arranges. Certificates of analysis differ widely in which tests they report and in the limits applied. The counter-ion introduced during purification, commonly acetate or trifluoroacetate, changes the net peptide content of a given mass of powder, so two samples of equal weight may not contain equal amounts of the active sequence. Third-party laboratories can verify purity, identity, residual solvents, and counter-ion content for a fee, which makes documentation more informative than labelling.
Verification of a sample usually begins with reversed-phase high-performance liquid chromatography, which resolves the peptide from truncated sequences and other impurities and expresses purity as a percentage of total peak area. Mass spectrometry by electrospray ionisation or matrix-assisted laser desorption supplies an independent check, because the measured mass can be compared against the theoretical value for AEDG. Amino acid analysis or tandem mass spectrometry sequencing can confirm residue order. Each of these methods answers a different question: a purity figure does not establish identity, and an identity match does not establish how much of the material is intact peptide.
The most frequently cited laboratory finding is that AEDG increased telomerase activity and extended telomere length in cultured human somatic cells. That work used fetal fibroblast strains and reported changes in enzyme activity alongside altered division counts. Replication by unrelated groups has been limited, and the published record is largely a single-laboratory series rather than a multi-centre programme. The result supports a hypothesis about peptide influence on gene expression in cell culture; it does not by itself establish an effect on telomere length in living animals or in people.
Animal and clinical reports appear mainly in Russian-language journals from the 1990s and 2000s, covering endpoints such as melatonin rhythm, lifespan in aged rodents, and retinal function. Many of these papers involve small groups, lack blinding or placebo comparison, and are difficult to retrieve through indexed databases. Review articles published in English generally summarise the claims without reanalysing the underlying data. Because no large randomised trial exists, the clinical importance of these reported effects stays unresolved and is properly described as an open question.
No national medicines regulator has approved epitalon as a therapeutic product. It is generally distributed as a research chemical, and in some jurisdictions selling peptides for human consumption without approval is restricted or prohibited. Certificates of analysis accompanying commercial material vary in which tests are performed, and independent verification of identity and purity is uncommon. Statements about anti-ageing or disease-prevention benefits on vendor pages are marketing claims rather than regulatory findings, a distinction that shapes how the compound is discussed in scientific and popular sources alike.
| Property | Value | Notes |
|---|---|---|
| Identity confirmation | Electrospray or MALDI mass spectrometry | Observed mass compared with theoretical 390.35 Da |
| Purity specification | 95 percent or greater by RP-HPLC | Common convention for research-grade peptide |
| Counter-ion | Acetate or trifluoroacetate | Affects net peptide content of a weighed sample |
| Solution storage | −80 °C as single-use aliquots | Repeated freeze–thaw cycles accelerate loss |
| Main degradation route | Aspartimide formation at Asp-Gly | Produces isoaspartate and related species |
Stability depends strongly on pH, temperature and the presence of oxygen and trace metals. Cleavage of the backbone proceeds faster under neutral to alkaline conditions, whereas acidic solutions tend to slow that reaction. The aspartate and glutamate side chains can undergo deamidation or imide formation over time, generating closely related impurities. Published stability data specific to epitalon are sparse, so the usable life of a given solution is best regarded as an open question that depends on buffer composition, concentration and storage temperature.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography with ultraviolet detection, frequently near 214 nanometers where the peptide bond absorbs. Mass spectrometry, most often with electrospray ionization, confirms the observed molecular mass and helps separate the intact peptide from truncated or modified forms. Amino acid analysis or tandem mass spectrometry can establish residue order. Purity is commonly quoted as an area percentage, yet such values are method-dependent, and comparisons between laboratories require matching column, gradient and detection wavelength.
Laboratory handling begins with dissolution of the lyophilized powder in water or a suitable aqueous buffer. The dry solid is the more stable form, so stock solutions are generally prepared only when required and kept cold afterwards. Repeated freezing and thawing of a solution is avoided because it encourages aggregation and gradual loss of the intact chain. Diluents and containers are selected to limit adsorption of a short peptide onto plastic surfaces and to reduce microbial growth in aqueous preparations.
Identity and purity are established with reversed-phase high-performance liquid chromatography and mass spectrometry. The chromatogram shows the main peak and any truncated or oxidised by-products, while the mass spectrum confirms the expected 390 dalton mass. Amino acid analysis can corroborate composition when a sample's origin is uncertain. Counterion content, particularly residual trifluoroacetate from purification, is frequently reported alongside purity because it shifts the net mass of the solid.
Reference material is normally supplied as a lyophilised powder in a sealed vial. Product literature typically recommends storage at minus twenty degrees Celsius or colder, protected from light and moisture. Freeze-thaw cycling is usually avoided because repeated condensation can introduce water into the vial. Working solutions are commonly prepared fresh, aliquoted, and kept cold for short periods rather than stored at ambient temperature. Labelling the date of opening helps track how long a vial has been in use.
Solubility is high in water, phosphate-buffered saline and normal saline, a pattern that follows from the two acidic residues in the chain. The peptide dissolves poorly in non-polar solvents such as hexane or chloroform. Stock solutions are often prepared in water first and then diluted into the buffer of interest. Because the molecule is small and hydrophilic, filtration through a low-protein-binding membrane is usually straightforward, and visible particulates are uncommon in freshly made solutions.
== Reactions == Hippuric acid is readily hydrolysed by hot caustic alkalis to benzoic acid and glycine. Nitrous acid converts it into benzoyl glycolic acid, C6H5C(=O)OCH2CO2H. Its ethyl ester reacts with hydrazine to form hippuryl hydrazine, C6H5CONHCH2CONHNH2, which was used by Theodor Curtius for the preparation of hydrazoic acid. Hippuric acid has also been used in Erlenmeyer–Plöchl synthesis of phenylalanine and other amino acids, the reaction proceeding via an oxazolone or "azlactone" intermediate.
The affair brought Anglo-Boer relations to a dangerous low. Tensions were further exacerbated by the "Kruger telegram" from Kaiser Wilhelm II congratulating Kruger on defeating the "raiders". The German telegram came to be widely interpreted as an offer of military aid to the Boers. Wilhelm was already perceived by many as anti-British after initiating a costly naval arms race between Germany and Britain. As tensions quickly mounted, the Transvaal began importing large quantities of arms and signed an alliance with the Orange Free State in 1897. Jan C. Smuts wrote in 1906 of the Raid, "The Jameson Raid was the real declaration of war ... And that is so in spite of the four years of truce that followed ... [the] aggressors consolidated their alliance ... the defenders on the other hand silently and grimly prepared for the inevitable." Joseph Chamberlain condemned the raid despite previously having approved Rhodes' plans to send armed assistance in the case of a Johannesburg uprising. In London, despite some condemnation by the print-media, most newspapers used the episode as an opportunity to whip-up anti-Boer feelings. Though they faced criminal charges in London for their actions in South Africa, Jameson and his raiders were treated as heroes by much of the popular public. Chamberlain welcomed the escalation by Transvaal as an opportunity to annex the Boer states.
=== Labour Party organiser === Galloway joined the Labour Party Young Socialists aged 13, having falsely claimed to have been 15, and was still a teenager when he became secretary of the Dundee Labour Party. Galloway became vice-chairman of the Labour Party in the City of Dundee and a member of the Scottish Executive Committee in 1975. On 5 May 1977, he contested his first election campaign in the Scottish district elections, but failed to hold the safe Labour Gillburn ward in Dundee, being defeated by the independent Bunty Turley. He became the secretary organiser of the Dundee Labour Party in 1977, and at 26, was the youngest ever chairman of the Scottish Labour Party in March 1981, a post he held for a year, after holding the vice-chairman post over the previous year. After a trip to Beirut, Lebanon, during 1977, Galloway became a supporter of Palestine, stating during his libel case against The Daily Telegraph in 2004 that "barely a week after my return I made a pledge, in the Tavern Bar in Dundee's Hawkhill District, to devote the rest of my life to the Palestinian and Arab cause." He supported Dundee City Council when it flew the Palestinian flag over the City Chambers building, and was involved in the twinning of Dundee with the Palestinian West Bank town of Nablus in 1980. In late 1981, in an interview for the Scottish Marxist, Galloway supported the affiliation of the Communist Party of Great Britain (CPGB) to the Labour Party, in the same way as the Fabian Society does.
Sources: en.wikipedia.org
=== Post-independence (1946–1962) === The first elections after independence were the 1947 parliamentary election, with the People's Party winning a plurality in the Chamber of Deputies, but no absolute majority. In 1949, a series of military coups led to the dissolution of the Chamber of Deputies and constitutional suspensions. A Constituent Assembly elected in 1949 drafted the 1950 constitution, which strengthened parliamentary powers. Adib al-Shishakli's 1951 coup dissolved the Chamber of Deputies, and his 1953 election, with only 16% voter turnout, reconstituted the Chamber of Deputies as a 82-member legislative body under a presidential system. After his ouster in 1954, parliamentary rule was restored, with the People's Party and Ba'ath Party gaining influence. In 1958, the Chamber of Deputies was replaced by the UAR's National Assembly, where Syrians held one-third of the seats. Following Syria's withdrawal, the 1961 election restored parliamentary democracy.
== Career == Following his postdoctoral fellowship at Harvard University, Lectka joined Johns Hopkins University as an assistant professor of chemistry in 1994. He was promoted to associate professor in 1999 and to professor in 2002. In 2012, he was appointed as the Jean and Norman Scowe Professor of Chemistry at Johns Hopkins University.
Moscow has a humid continental climate (Köppen climate classification: Dfb) with long, cold winters usually lasting from mid-November to the end of March, along with warm summers. More extreme continental climates at the same latitude—such as parts of Eastern Canada or Siberia—have much colder winters than Moscow does, suggesting that Moscow receives significant moderation from the Atlantic Ocean, even though the city is distant from it. Weather in Moscow can fluctuate widely: in the winter, temperatures range from −25 °C (−13 °F) in the city and −30 °C (−22 °F) in the suburbs to above 5 °C (41 °F); in the summer, temperatures range from 10 to 35 °C (50 to 95 °F).
During the initial outbreak in Wuhan, China, various names were used for the virus; some names used by different sources included "the coronavirus" or "Wuhan coronavirus". In January 2020, the World Health Organization (WHO) recommended "2019 novel coronavirus" (2019-nCoV) as the provisional name for the virus. This was in accordance with WHO's 2015 guidance against using geographical locations, animal species, or groups of people in disease and virus names. On 11 February 2020, the International Committee on Taxonomy of Viruses adopted the official name "severe acute respiratory syndrome coronavirus 2" (SARS‑CoV‑2). To avoid confusion with the disease SARS, the WHO sometimes refers to SARS‑CoV‑2 as "the COVID-19 virus" in public health communications and the name HCoV-19 was included in some research articles. Referring to COVID-19 as the "Wuhan virus" has been described as dangerous by WHO officials, and as xenophobic by many journalists and academics.
Sources: en.wikipedia.org
=== Integumentary === The integumentary system is the set of organs forming the outermost layer of the human body, comprising the skin, hair, and nails. It acts as a protective physical barrier between the external environment and the internal environment, while maintaining water balance, protecting deeper tissue, excreting waste, and regulating body temperature. The skin (or, integument) is a composite organ, made up of the outermost epidermis and the inner dermis. The epidermis comprises five layers: the stratum corneum, stratum granulosum, stratum spinosum and stratum basale. Where the skin is thicker, such as in the palms and soles, there is an extra layer of skin between the stratum corneum and the stratum granulosum known as the stratum lucidum. The dermis comprises two sections, the papillary and reticular layers, and contains connective tissues, blood vessels, glands, follicles, hair roots, sensory nerve endings, and muscular tissue. Between the integument and the deep body musculature there is a transitional subcutaneous zone, the hypodermis.
=== Cleaning of cork === Natural cork is a suberin based natural polymer foam that can have unpleasant substances which are responsible for the loss of quality in wine. The leading substance is 2,4,6 trichloroanisole (TCA), which can be detected at concentrations as low as 2 ng/l in the wine. Supercritical CO2 is used at industrial scale to remove this substance and guarantee that the wine retains its full quality.
Glutamate is the most abundant excitatory neurotransmitter in the vertebrate nervous system. At chemical synapses, glutamate is stored in vesicles. Nerve impulses trigger the release of glutamate from the presynaptic cell. Glutamate acts on ionotropic and metabotropic (G-protein coupled) receptors. In the opposing postsynaptic cell, glutamate receptors, such as the NMDA receptor or the AMPA receptor, bind glutamate and are activated. Because of its role in synaptic plasticity, glutamate is involved in cognitive functions such as learning and memory in the brain. The form of plasticity known as long-term potentiation takes place at glutamatergic synapses in the hippocampus, neocortex, and other parts of the brain. Glutamate works not only as a point-to-point transmitter, but also through spill-over synaptic crosstalk between synapses in which summation of glutamate released from a neighboring synapse creates extrasynaptic signaling/volume transmission. In addition, glutamate plays important roles in the regulation of growth cones and synaptogenesis during brain development as originally described by Mark Mattson.
In June 1884, British imperial interests were ignited in the discovery by Jan Gerrit Bantjes of what would prove to be the world's largest deposit of gold ore at an outcrop on a ridge 69 km (43 mi) south of the Boer capital at Pretoria. The ridge was known locally as the "Witwatersrand" (white water ridge, a watershed). A gold rush to the Transvaal brought thousands of British and other prospectors from around the globe and over the border from the Cape Colony, which had been under British control since 1806.
Fast growing microorganisms such as bacteria and yeast have a high concentration of nucleic acid, notably RNA. Levels must be limited in the diets of monogastric animals to <50 g per day. Ingestion of purine compounds arising from RNA breakdown leads to increased plasma levels of uric acid, which can cause gout and kidney stones. Uric acid can be converted to allantoin, which is excreted in urine. Nucleic acid removal is not necessary from animal feeds but is from human foods (humans have lost parts of the uric acid catabolic pathway during their evolution). This problem can be remediated, however. One common method consists in a heat treatment which kills the cells, inactivates proteases and allows endogenous RNases to hydrolyse RNA with release of nucleotides from cell to culture broth.
Sources: en.wikipedia.org
Mass spectrometry provides the identity check, because the observed mass is compared with the theoretical mass of the AEDG sequence. Chromatography separates and quantifies impurities but does not by itself prove which peptide is present. The two techniques are normally used together.
Yes. Trifluoroacetate and acetate ions remain associated with the peptide after purification, so a weighed quantity of powder contains less peptide than the nominal mass suggests. Certificates that report net peptide content rather than raw weight are more directly comparable between suppliers.
Dilute aqueous solutions are less stable than the dry powder and are usually aliquoted and frozen to avoid repeated freeze–thaw cycles. Lyophilised material is best stored desiccated at −20 °C, protected from light. Working solutions are typically prepared fresh from a frozen aliquot.
Small studies with human participants have been reported, chiefly in Russian-language journals, but they are limited in size and design. No large randomised controlled trial with published results is available.