epithalamin comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-09-07. Where a claim depends on a specific study, the study is described rather than over-claimed.
Dissolution is usually performed in water or a suitable aqueous buffer, and the resulting liquid is divided into single-use portions before freezing. Freeze-thaw cycling is a recognised source of loss for short peptides, since each cycle can encourage aggregation or adsorption onto container walls. Working solutions are generally kept cold and used within a short window, although published stability data specific to epitalon are thin. Containers should be marked with concentration and date, and solutions examined for cloudiness before use.
Identity is normally established by reversed-phase high-performance liquid chromatography combined with mass spectrometry, a pairing that separates components and confirms molecular mass at once. Purity is quoted as a percentage from the chromatogram, and figures above ninety-five percent are a frequent commercial specification. Amino acid analysis or sequencing supplies further confirmation when required. Because many short peptides behave similarly under chromatography, retention time alone does not establish sequence; the mass measurement is what separates one tetrapeptide from another, and certificates should report both.
Published evidence comes mainly from Russian-language journals and from a single research group, with small sample sizes and limited independent replication. A few laboratories outside that group have examined related peptides and reported weaker or absent telomerase effects, so the central claim is best described as contested rather than settled. Rodent studies report modest changes in some ageing markers and in survival, but designs vary and control conditions are often sparse. No large randomised trial in humans has been published, and long-term safety data in healthy populations are correspondingly thin.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. It was designed at the St. Petersburg Institute of Bioregulation and Gerontology as a short, chemically defined analogue of epithalamin, a fraction obtained from bovine pineal tissue. Small peptide bioregulators of this type formed a long-running line of work there from the 1980s onward. Because the molecule is produced by solid-phase synthesis rather than extraction, its composition is exact and its purity can be measured directly.
| Property | Value | Notes |
|---|---|---|
| Sequence | Ala-Glu-Asp-Gly | Written in three-letter amino acid code |
| Single-letter code | AEDG | Form used in most catalogue entries |
| Typical purity specification | 95 percent or higher | Value read from the HPLC chromatogram |
| Storage, dry solid | Minus 20 degrees Celsius, desiccated | Sealed container, protected from light |
| Handling, solution | Divide into single-use portions | Limits losses from freeze-thaw cycling |
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.
Several names circulate for the same molecule, including epitalon, epithalone, epithalamin tetrapeptide, and the sequence code AEDG. A CAS registry number, 307297-39-8, is commonly cited for it, though catalogue entries should be checked against supplier documentation because mislabelled records occur. In its usual form the peptide carries free amino and carboxyl termini and is neither glycosylated nor lipidated. Researchers distinguish the defined tetrapeptide from epithalamin itself, a crude pineal preparation containing many peptides that is not chemically characterised.
Material supplied for laboratory use is normally a lyophilised white to off-white powder that dissolves readily in water and in isotonic saline. Lyophilised cakes are hygroscopic and should be equilibrated to room temperature before opening to limit condensation on the solid. Solutions are typically prepared at milligram-per-millilitre concentrations and divided into single-use aliquots, because repeated freeze–thaw cycles degrade short peptides. Aqueous solutions are far less stable than the dry powder, and identity is usually verified by mass spectrometry alongside purity estimation from reversed-phase high-performance liquid chromatography.
Epitalon is a synthetic linear tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and the calculated mass is approximately 390.35 g/mol. The compound is made by solid-phase peptide synthesis rather than extracted from tissue, although early work described it as a short fragment of a peptide fraction obtained from bovine pineal extract. In the research literature the spelling epitalon and the variant epithalone both appear, while AEDG is the standard code used in peptide nomenclature.
Typical storage for the lyophilized powder is −20 °C or lower, in a sealed container protected from light and moisture. Hygroscopic material should be allowed to equilibrate to room temperature before the vial is opened, which limits condensation on the contents. Working solutions are commonly divided into single-use aliquots and frozen to avoid repeated freeze-thaw cycles. Dilute solutions are more prone to adsorption onto plastic surfaces and to loss during filtration, so procedures that minimize transfers and use low-binding labware are preferable.
Reversed-phase high-performance liquid chromatography is the standard approach for assessing purity, usually with ultraviolet detection near 214 nm, where the peptide bond absorbs. Mass spectrometry, most often with electrospray ionization, confirms the molecular mass and helps reveal truncation or deletion byproducts. Amino acid analysis can verify composition, and counterion content is sometimes measured because peptides purified with trifluoroacetic acid retain variable amounts of that salt. Purity figures reported without a stated method and detection wavelength are difficult to interpret.
The cell counters of that time used LED screens for result review. In 1982, Medonic AB, another Swedish company with focus on hematology, was founded. The founders, Ingemar Berndtsson and Abraham Bottema, both had a long history and experience in hematology, clinical chemistry, and blood banking engineering. In 1985, Medonic AB launched the Cellanalyzer CA 480 system, its first own-developed cell counter with a built-in display that also showed the cell histograms. When computers began to be incorporated into the analyzers, other brands, like the Swelab analyzers, also came with a display. Both targeting the smaller clinical laboratories, Swelab Instrument AB and Medonic AB were competitors on the decentralized hematology testing market. In the late 90s, both Swelab Instrument AB and Medonic AB were acquired by Boule Diagnostics AB. The company has kept the parallel brands and the analyzers are still manufactured from its facilities in Stockholm, Sweden and supplied under the Swelab and Medonic trademarks for the decentralized hematology testing market. When Coulter was acquired by Beckman, former Coulter employees Dr. Harold R Crews, Andrew C Swanson, and Donald Grantham founded Clinical Diagnostic Solutions, Inc. (CDS) in 1997, focusing on the development and production of generic reagents and control material. In 2004, CDS was acquired by Boule. By this acquisition, Boule came to master the skills of the development and production of both instruments and the consumables included in a complete hematology system.
== Early life and education == Balalaie was born on 26 September 1965 in Rasht, Gilan Province, Iran. He completed his undergraduate studies in Chemistry at the University of Tehran (1984–1989), followed by a Master of Science degree in Organic Chemistry from Shahid Beheshti University (1989–1991). He earned his Ph.D. in Organic Chemistry from Sharif University of Technology (1992–1996), where he worked on "Photooxygenation of organic compounds by singlet oxygen" under the supervision of Professor Mohammad Mahmoudi Hashemi. During his doctoral studies, he spent six months as a visiting researcher in Germany working with Professor Junes Ipaktschi.
=== Anti-inflammation === Inhibiting inflammatory mediators could help prevent osteoarthritis progression. Cytokines and chemokines are both crucial in stimulating cartilage catabolism and blocking these inflammatory mediators. Studies have shown that treatment with NF-κB pathway inhibitor BAY11-7082 restores IL-1b-inhibited chondrogenesis of cartilage stem cells and in turn postpones progression of OA. Similarly, ample research shows that combined blockade of TNFa and IL-17 with bispecific antibodies reveals an inhibition of both cytokines for reduced cartilage degradation and proinflammatory responses.
There has been uncertainty about which biological target interactions mediate the psychoactive and other effects of ibogaine. Rodent drug discrimination studies with ibogaine have been employed to help elucidate these interactions. Ibogaine partially substitutes for the serotonergic psychedelics LSD and DOM and this can be blocked by the serotonin 5-HT2 receptor antagonist pizotifen. Similarly, LSD and DOM partially substitute for ibogaine and this can be blocked by the serotonin 5-HT2A receptor antagonist pirenperone. The serotonin releasing agent and potent serotonin 5-HT2 receptor agonist fenfluramine also partially substitutes for ibogaine. The preferential serotonin 5-HT2C receptor agonists MK-212 and mCPP partially substitute for ibogaine as well and this can be blocked by the serotonin 5-HT2 receptor antagonist metergoline. The preceding findings suggest that serotonin 5-HT2A and 5-HT2C receptor activation are involved in the subjective effects of ibogaine. Conversely, the serotonin 5-HT1A and 5-HT3 receptors do not appear to be involved. Although serotonin 5-HT2A receptor signaling appears to be involved in the effects of ibogaine, neither ibogaine nor its major active metabolite noribogaine appears to act as a direct serotonin 5-HT2A receptor agonist. In addition, in contrast to the findings in drug discrimination studies, ibogaine fails to produce the head-twitch response, a behavioral proxy of psychedelic effects, in rodents.
== Other uses == The nutrition-rich nature of yeast extract lends it to a variety of uses. It was historically popular as a vitamin supplement for humans. Rich in proteins and nucleotides, it currently finds use in animal feed and microbiology (see yeast extract agar) as nutritional supplements. It also finds use in cosmetics and skincare products due to its alleged moisturizing and antioxidant properties.
Sources: en.wikipedia.org
an α-amino acid + an alcohol This enzyme belongs to the family of hydrolases, specifically those acting on carboxylic ester bonds. The systematic name is α-amino-acid-ester aminoacylhydrolase. This enzyme is also called α-amino acid ester hydrolase.
Alcora Exercise Angolan Civil War Cuban intervention in Angola List of operations of the South African Border War Namibian Czechs Portuguese Colonial War Rhodesian Bush War South Africa and weapons of mass destruction
nucleus pl. nuclei A large spherical or lobular organelle surrounded by a dedicated membrane which functions as the main storage compartment for the genetic material of eukaryotic cells, including the DNA comprising chromosomes, as well as the site of RNA synthesis during transcription. The vast majority of eukaryotic cells have a single nucleus, though some cells may have more than one nucleus, either temporarily or permanently, and in some organisms there exist certain cell types (e.g. mammalian erythrocytes) which lose their nuclei upon reaching maturity, effectively becoming anucleate. The nucleus is one of the defining features of eukaryotes; the cells of prokaryotes such as bacteria lack nuclei entirely.
C6H5OH + Hg(O2CCH3)2 → C6H4(OH)–HgO2CCH3 + CH3CO2H C6H4(OH)–HgO2CCH3 + NaCl → C6H4(OH)–HgCl + NaO2CCH3 The first such reaction, including a mercuration of benzene itself, was first reported by Otto Dimroth in 1898.
=== 27 June === In Donetsk Oblast, two people were killed by Russian shelling in Kurakhove, while one person was killed in a separate attack in Toretsk. The Ukrainian military claimed to have driven out Russian forces from the Kanal neighborhood of Chasiv Yar. Russian media reported that an explosion occurred at a chemical plant in Tver Oblast following a drone strike. The plant is believed to manufacture aviation fuel. According to local residents four drones struck the plant, damaging a workshop, pipeline and roof. No casualties were reported and Russian authorities claimed all four drones were destroyed.
Sources: en.wikipedia.org
=== Chemistry === According to chemical weapons expert Jonathan Tucker, the first binary formulation developed under the Foliant programme was used to make Substance 33 (VR), very similar to the more widely known VX, differing only in the alkyl substituents on its nitrogen and oxygen atoms. "This weapon was given the code name Novichok."
The concomitant use of elagolix with medications that inhibit OATP1B1 may increase elagolix levels, and the use of elagolix with strong OATP1B1 inhibitors like ciclosporin and gemfibrozil, which may markedly increase elagolix exposure, is contraindicated. Elagolix is a weak to moderate inducer of CYP3A, and may decrease levels of medications that are substrates of CYP3A4. In addition, elagolix is an inhibitor of P-glycoprotein, and may increase levels of medications that are substrates of P-glycoprotein, such as digoxin. Elagolix has been found to increase exposure to digoxin and ethinylestradiol, whereas it has been found to decrease exposure to rosuvastatin, midazolam, norethisterone, norelgestromin, and norgestrel. Because combined birth control pills and other forms of combined birth control contain an estrogen, and because elagolix treats endometriosis by decreasing estrogen levels in the endometrium, these form of hormonal birth control are likely and expected to decrease the effectiveness of elagolix in the treatment of this condition. The effect of progestogen-only birth control on the effectiveness of elagolix in endometriosis is unknown. However, progestogens are antiestrogenic in the uterus, and high-dose progestin therapy is known to be effective in the treatment of endometriosis similarly to GnRH antagonists. On the basis of limited clinical research, combined birth control pills have also been found to be effective in the treatment of endometriosis, but are likely not as effective as GnRH modulator monotherapy.
=== July === 1 July – Local Government Minister Lee Rowley formally writes to South Cambridgeshire District Council to request they end their trial of a four-day working week "immediately" amid concerns about "value for money". The scheme, launched in January 2023, is scheduled to run until March 2024. Seven Just Stop Oil protestors are arrested after attempting to disrupt the 2023 London Pride celebrations by blocking the route of the parade. Five people are subsequently charged in connection with the incident. 2 July – Amanda Pritchard, the Chief Executive of NHS England, announces the launch of a further seven specialist gambling addiction clinics in England as the number of people being referred for help because of gambling addiction sees a sharp increase. 3 July – Lord Chancellor and Justice Secretary Alex Chalk asks the Parole Board to reconsider its decision to release child killer Colin Pitchfork. Ranibizumab, a drug that can prevent blindness in premature babies, is made available on the NHS in England. 4 July – Thames Water is fined £3.3m for discharging millions of litres of untreated sewage into two rivers which resulted in the death of 1,400 fish. Forest Green Rovers appoint Hannah Dingley as their caretaker manager, making her the first woman to manage a men's football team in English professional football. 5 July – Train companies in England launch a 21-day consultation over plans to closing hundreds of ticket offices. Two Just Stop Oil protestors briefly halt play at the 2023 Wimbledon Championships by invading the tennis court and throwing orange confetti.
Protein identification is the process of assigning a name to a protein of interest (POI), based on its amino-acid sequence. Typically, only part of the protein’s sequence needs to be determined experimentally in order to identify the protein with reference to databases of protein sequences deduced from the DNA sequences of their genes. Further protein characterization may include confirmation of the actual N- and C-termini of the POI, determination of sequence variants and identification of any post-translational modifications present.
Sources: en.wikipedia.org
Reversed-phase high-performance liquid chromatography is run alongside mass spectrometry. The chromatogram separates components and gives a purity figure, while the mass spectrum confirms that the measured molecular mass matches the expected sequence. Neither measurement on its own is treated as sufficient.
Long-term holding is usually at minus twenty degrees Celsius in a sealed, desiccated container. A refrigerator is adequate for short intervals before use. Light exposure is normally avoided as well. Allowing a cold container to warm before opening reduces moisture condensation on the contents.
Repeated cycles are generally avoided. Each freeze and thaw can promote aggregation or loss of peptide to container surfaces, which reduces the amount available for later work. Dividing a solution into single-use portions at the outset is the usual way to limit this problem.
No. Epithalamin is a peptide-containing extract of bovine pineal glands, while epitalon is a single synthetic tetrapeptide. The extract contains many peptides and other tissue components, so its composition varies between batches in ways that a synthesised sequence does not.