The short version of Pineal peptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
Stability of the tetrapeptide follows ordinary peptide chemistry rather than any unusual structural feature. The aspartate-glycine pair is prone to aspartimide formation under mildly basic or neutral conditions, and deamidation can follow, altering both mass and chromatographic retention. Dry lyophilised powder kept at or below minus twenty degrees Celsius is the usual handling recommendation, with repeated freeze-thaw cycles avoided. Once dissolved in neutral aqueous buffer, degradation proceeds over days to weeks depending on pH and temperature, while acidic conditions generally slow the aspartimide route. A formal stability-indicating study has not been published in the indexed literature.
Because epitalon has no pharmacopoeial monograph, quality assessment depends on supplier documentation and independent testing. Certificates of analysis typically report a purity figure from a single chromatographic run, a measured mass and sometimes an appearance description, but methods and acceptance criteria are not harmonised across vendors. Third-party laboratories can repeat identity and purity measurements, and mismatches between labelled and measured peptide content have been described for research peptides generally. What constitutes adequate identity confirmation for a molecule of this size stays an open question, since mass agreement alone does not separate closely related sequences.
Identity testing for epitalon relies on reversed-phase high-performance liquid chromatography for purity and mass spectrometry for mass confirmation. Because the sequence contains no tryptophan or tyrosine, ultraviolet detection at 280 nanometres is insensitive, so chromatographic methods usually monitor absorbance near 214 nanometres, where the peptide backbone absorbs. Electrospray ionisation or matrix-assisted laser desorption/ionisation then checks the intact mass against the expected value near 390 daltons. Peptide mapping or amino acid analysis after acid hydrolysis can supplement these measurements, although such confirmatory work is seldom reported on commercial certificates of analysis.
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.
| Property | Value | Notes |
|---|---|---|
| Analytical method | Reversed-phase HPLC | Purity determination, typically 214 nm |
| Mass confirmation | ESI or MALDI mass spectrometry | Compared with mass near 390 Da |
| Common synonyms | Epitalon, epithalon, AEDG | Naming differs between suppliers |
| Storage temperature | −20 °C or lower | Lyophilised powder, kept desiccated |
| Solution stability | Limited in neutral aqueous buffer | Aspartimide and hydrolysis pathways |
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.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
Epitalon is a synthetic tetrapeptide whose sequence is alanine-glutamate-aspartate-glycine, written in single-letter code as AEDG. The four residues are joined by three peptide bonds, giving a linear backbone with no branching and no disulfide bridges. Its calculated molecular mass for the free form is approximately 390.3 daltons, a figure that rises when the compound is supplied as an acetate or trifluoroacetate salt. Because the chain is short, the molecule is defined entirely by its residue order rather than by any folded three-dimensional structure.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
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.
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.
Literature searches for this compound must account for several spelling variants. Indexing databases contain epitalon, epithalon, epithalone, and AEDG, and relevant records are scattered across Russian-language and English-language journals that do not consistently cross-cite. Early publications describe the parent extract as a mixture of many peptides, whereas later work addresses the single synthetic tetrapeptide. That shift in nomenclature complicates comparison between studies, because extract data and tetrapeptide data are sometimes cited interchangeably. A search strategy omitting the alternate spellings will return an incomplete set of references.
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.
=== Electrical === In electrical FFF a transverse electrical current (DC) is applied which creates an electric field. Depending on the charge of sample components, an electrophoretic drift velocity is induced, counteracted by the diffusion from Brownian motion, so the separation depends on the ratio of electrophoretic mobility and size. Application of electrical FFF has been limited and is currently rarely used. Other modifications have been developed, namely cyclical electrical FFF where a special alternating current is applied. It allows to separate according to electrophoretic mobility. Another variation is electrical asymmetrical flow FFF (EAF4), where an electrical field is applied in addition to a cross flow field. EAF4 overcomes the limitation of pure electrical FFF which has poor resolution and suffers from electrolysis products and bubbles contaminating the channel outflow and compromising the detector signals.
== Names == The term "sand dollar" derives from the appearance of the tests (skeletons) of dead individuals after being washed ashore. The test lacks its velvet-like skin of spines and has often been bleached white by sunlight. To beachcombers of the past, this suggested a large, silver coin, such as the old Spanish dollar, which had a diameter of 38–40 mm. Other names for the sand dollar include sand cakes, pansy shells, snapper biscuits, cake urchins, and sea cookies. In South Africa, they are known as pansy shells from their suggestion of a five-petaled garden flower. The inflated sea biscuit or Caribbean sand dollar, Clypeaster rosaceus, is thicker in height than most. In Spanish-speaking areas of the Americas, the sand dollar is most often known as galleta de mar ("sea cookie"); the translated term is often encountered in English.
Overall, without considering race, approximately 1.5% of infants born in the United States are carriers of at least one copy of the mutant (disease-causing) gene. In June 2026 it was reported that Daniel Cressy, an African American from Louisiana was cured from the disease after going through curative gene therapy.
After completing her PhD, Dayhoff studied electrochemistry under Duncan A. MacInnes at the Rockefeller Institute from 1948 to 1951. In 1952, she moved to Maryland with her family and later received research fellowships from the University of Maryland (1957–1959), working on a model of chemical bonding with Ellis Lippincott. At Maryland, she gained her first exposure to a new high-speed computer, the IBM model 7094. After this ended, she joined the National Biomedical Research Foundation in 1960 as associate director (a position she held for 21 years). At the NBRF, she began to work with Robert Ledley, a dentist who had obtained a degree in physics and become interested in the possibilities of applying computational resources to biomedical problems. He had authored one of the earliest studies of biomedical computation, "Report on the Use of Computer in Biology and Medicine." With their combined expertise, they published a paper in 1962 entitled "COMPROTEIN: A computer program to aid primary protein structure determination" that described a "completed computer program for the IBM 7090" that aimed to convert peptide digests to protein chain data. They actually began this work in 1958, but were not able to start programming until late 1960.
== Awards == Royal Society of Western Australia, University Medal for outstanding student in natural and earth sciences (2003) Society of Environmental Toxicology and Chemistry, Best Platform Presentation by a student (2008) FNR ATTRACT Fellowship for the development of new methods to identify unknown chemicals (2018) The Analytical Scientist, Top 40 under 40 Power List (2018) The Analytical Scientist Power List, "Planet Protectors" field (2024)
Sources: en.wikipedia.org
In parallel, he decided to try out for Saturday Night Live again, this time ahead of the show's 1985–86 season being prepared by returning executive producer Lorne Michaels who was looking to hire an all-new cast. Five years removed from his previous SNL audition, twenty-three-year-old Carrey was rejected again, reportedly never even getting the chance to audition his material—'post-nuclear Elvis' hybrid impression and impersonation of Henry Fonda from On Golden Pond—in front of executive producer Michaels due to the show's producers and senior writers Al Franken, Tom Davis, and Jim Downey deciding that Michaels would not like it. Unlike his previous SNL rejection, Carrey now had a bit of a film career to fall back on in addition to his impressionist stand-up act; Once Bitten was released in mid November 1985 and turned out to be a modest box-office hit despite drawing poor reviews. Back on the comedy club circuit with impressions, in fall 1986, Carrey auditioned for SNL's upcoming season, his third attempt at getting on the ensemble sketch comedy show. Finally managing to perform for the show's executive producer Lorne Michaels at a Burbank studio, with returning cast members Dennis Miller, Jon Lovitz, and Nora Dunn also watching the audition, Carrey was rejected again. Among the group of hopefuls auditioning alongside Carrey on this occasion were Dana Carvey and Phil Hartman, both of whom were hired. Sensing that doing only impressions was turning into a career dead-end, Carrey set out to develop a new live comedy act.
During the 1982–83 event, jack mackerel and anchoveta populations were reduced, scallops increased in warmer water, but hake followed cooler water down the continental slope, while shrimp and sardines moved southward, so some catches decreased while others increased. Horse mackerel have increased in the region during warm events. Shifting locations and types of fish due to changing conditions create challenges for the fishing industry. Peruvian sardines have moved during El Niño events to Chilean areas. Other conditions provide further complications, such as the government of Chile in 1991 creating restrictions on the fishing areas for self-employed fishermen and industrial fleets. Southern Brazil and northern Argentina also experience wetter than normal conditions during El Niño years, but mainly during the spring and early summer. Central Chile receives a mild winter with large rainfall, and the Peruvian-Bolivian Altiplano receives more precipitation during its rainy season, sometimes being exposed to unusual winter snowfall events. Drier and hotter weather occurs in parts of the Amazon River Basin, Colombia, and Central America. During a time of La Niña, drought affects the coastal regions of Peru and Chile. From December to February, northern Brazil is wetter than normal. La Niña causes higher than normal rainfall in the central Andes, which in turn causes catastrophic flooding on the Llanos de Mojos of Beni Department, Bolivia. Such flooding is documented from 1853, 1865, 1872, 1873, 1886, 1895, 1896, 1907, 1921, 1928, 1929 and 1931.
== Classes and categories == Weight classes: Most powerlifting federations use the following weight classes: Men: −52 kg, −56 kg, −60 kg, −67.5 kg, −75 kg, −82.5 kg, −90 kg, −100 kg, −110 kg, −125 kg, −140 kg, 140 kg+ Women: −44 kg, −48 kg, −52 kg, −56 kg, −60 kg, −67.5 kg, −75 kg, −82.5 kg, −90 kg, 90 kg+ IPF weight classes: In 2010, the IPF introduced the following new weight classes effective 1 January 2011: Men: −53 kg (sub-junior/junior), −59 kg, −66 kg, −74 kg, −83 kg, −93 kg, −105 kg, −120 kg, 120 kg+ Women: −43 kg (sub-junior/junior), −47 kg, −52 kg, −57 kg, −63 kg, −72 kg, −84 kg, 84 kg+ In 2020, the IPF announced the 72 kg weight class would be replaced with the 69 and 76 kg weight class effective 1 January 2021. Age categories Age categories are depended on the federation. The IPF uses the following age categories: sub-junior (14–18), junior (19–23), open (any age), masters 1 (40–49), masters 2 (50–59), masters 3 (60–69), masters 4 (70+). Age categories are dependent on the year of the participant's birth. For example, if an athlete turns 18 years old in July, the athlete is considered an 18-year-old sub-junior throughout the calendar year. Other federations typically break the Masters categories down to 5-year increments, for example, 40–44, 45–49, 50–54, etc. Some federations also include a sub-master class from 33 (or 35) to 39, however some of these federations only use this category for record keeping purposes and do not use it as a competitive category in meets.
φ29’s DNA packaging system, using pRNA, incorporates a motor for the delivery of therapeutic molecules like ribozymes and aptamers. The small size of pRNA-derived nanoparticles also helps to deliver drugs in tight spaces like blood vessels. The main difficulty in using aptamer-based drug delivery is sourcing unique aptamers and other multimers for specific treatments for diseases that potentially degrade therapeutic multimers and nanoparticles in vivo. Nanoparticles need to be stabilized as delivery mechanisms in order to adapt to microenvironments that may result in loss of therapeutic cargo.
Hasegawa, Shuichi; Levin, Christoph; Radner, Karen, eds. (2018). The Last Days of the Kingdom of Israel. Walter de Gruyter GmbH & Co KG. ISBN 978-3-11-056660-4. Joffe, Alexander H. (2002). "The Rise of Secondary States in the Iron Age Levant". Journal of the Economic and Social History of the Orient. 45 (4): 425–467. doi:10.1163/156852002320939311. JSTOR 3632872. McNutt, Paula (1999). Reconstructing the Society of Ancient Israel. Westminster John Knox Press. ISBN 978-0-664-22265-9. Archived from the original on 1 July 2023. Retrieved 14 August 2015. Manzur, Ibn (1979). "SMR". Lisan al Arab. Vol. 21. Al-dar al-Misriya li-l-talif wa-l-taryamar. ISBN 978-0-866-85541-9. Mendels, D. (1987). The Land of Israel as a Political Concept in Hasmonean Literature: Recourse to History in Second Century B.C. Claims to the Holy Land. Texte und Studien zum antiken Judentum. J.C.B. Mohr. ISBN 978-3-16-145147-8. Retrieved 7 December 2020. Na'aman, Nadav (2011). "The Exodus Story: Between Historical Memory and Historiographical Composition". Journal of Ancient Near Eastern Religions. 11: 39–69. doi:10.1163/156921211X579579. Redmount, Carol A. (2001) [1998]. "Bitter Lives: Israel in and out of Egypt". In Coogan, Michael D. (ed.). The Oxford History of the Biblical World. Oxford and New York: Oxford University Press. pp. 58–89. ISBN 978-0-19-513937-2. Archived from the original on 3 April 2023. Retrieved 26 June 2023. Tetley, M. Christine (2005). The Reconstructed Chronology of the Divided Kingdom. Eisenbrauns. pp. 105–. ISBN 978-1-57506-072-9. Tubb, Jonathan N. (1998). Canaanites.
Sources: en.wikipedia.org
Elbasvir/grazoprevir, sold under the brand name Zepatier, is a fixed-dose combination for the treatment of hepatitis C, containing elbasvir (an inhibitor of hepatitis C virus's NS5A protein) and grazoprevir (an NS3/4A inhibitor). It is used to treat chronic hepatitis C virus (HCV) genotypes 1 or 4 infection in both treatment-naïve and treatment-experienced patients. Both elbasvir and grazoprevir were developed by Merck & Co. The US Food and Drug Administration (FDA) approved the drug in January 2016.
== Research and publications == Davies has authored numerous peer-reviewed articles on diabetes and related conditions. Her work has appeared in journals such as The Lancet, New England Journal of Medicine, and Diabetes Care.
== History == Breakthrough T1D was founded in 1970 by a group of parents of children living with type 1 diabetes. It was originally named the Juvenile Diabetes Foundation. The founding members formed the organization with the intent to find a cure for type 1 diabetes and its complications by supporting research. It adopted what was at the time a novel organizational structure, where non-experts participated in developing research and advocacy policies. The creation of international affiliates followed:
=== Disbandment === Ahead of the multi-racial 1980 Southern Rhodesian general election the Selous Scouts and SAS were involved in preparing plans to annul its results. One of these plans would have involved killing the leadership of the black nationalist parties in Operation Hectic. Another, designated Operation Quartz would have involved attacking the insurgents in the camps where they had been concentrated within Rhodesia ahead of the election. These operations were not attempted. Following the transition to majority rule and Rhodesia's reconstitution as Zimbabwe, Prime Minister Robert Mugabe decided in March 1980 to disband the Selous Scouts by April that year. Mugabe stated that the unit needed to be disbanded as part of reforms to provide Zimbabwe with a "respectable" army. At this time it was expected that many of its white members would leave the military. Walls received a hostile reception from the unit's officers and men when he visited its base in March 1980. During this visit members of the Selous Scouts called him a traitor. The Selous Scouts were disbanded without a formal ceremony to mark the occasion in April 1980. The unit had suffered between 30 and 35 fatalities during its existence. Most of the white members of the Selous Scouts moved to South Africa to join that country's security forces. The 900 black members of the unit were offered other positions within Zimbabwe's security forces, and were mainly split across three battalions of the Rhodesian African Rifles.
== Signs and symptoms == Symptoms of this disease include deterioration of motor functions and speech, seizures, and other involuntary movement. Other symptoms are headaches, dementia, and vision impairment. Characteristics of Parkinson's Disease are also similar to PFBC. The disease usually manifests itself in the third to fifth decade of life but may appear in childhood or later in life. It usually presents with clumsiness, fatigability, unsteady gait, slow or slurred speech, difficulty swallowing, involuntary movements or muscle cramping. Seizures of various types are common. Neuropsychiatric symptoms, which may be the first or the most prominent manifestations, range from mild difficulty with concentration and memory to changes in personality and/or behavior, to psychosis and dementia.
Sources: en.wikipedia.org
The molecule lacks aromatic residues, so it absorbs weakly near 280 nanometres, the wavelength applied to many other peptides. The peptide bond absorbs strongly below 220 nanometres, making 214 nanometres a practical compromise. Gradient methods must therefore use mobile phases with low ultraviolet absorbance to keep the baseline clean.
Neutral and slightly basic aqueous conditions promote aspartimide formation at the aspartate-glycine step, often followed by deamidation. Elevated temperature and repeated freeze-thaw cycles accelerate the loss. Acidic solutions and dry lyophilised powder are comparatively stable over short periods.
No monograph exists in the United States Pharmacopeia or the European Pharmacopoeia, and no widely distributed certified reference standard is available. Purity and identity therefore rest on supplier methods that are not harmonised. This absence is the main reason reported purities are difficult to compare between sources.
Epitalon is a synthetic tetrapeptide built from four amino acids: alanine, glutamate, aspartate, and glycine. It is not extracted from a natural source but made in the laboratory by chemical synthesis. Its short length makes it relatively straightforward to produce at high purity.